WorldWideScience

Sample records for brood pheromone modulated

  1. Effects of brood pheromone (SuperBoost) on consumption of protein supplement and growth of honey bee (Hymenoptera: Apidae) colonies during fall in a northern temperate climate.

    Science.gov (United States)

    Sagili, Ramesh R; Breece, Carolyn R

    2012-08-01

    Honey bee, Apis mellifera L. (Hymenoptera: Apidae), nutrition is vital for colony growth and maintenance of a robust immune system. Brood rearing in honey bee colonies is highly dependent on protein availability. Beekeepers in general provide protein supplement to colonies during periods of pollen dearth. Honey bee brood pheromone is a blend of methyl and ethyl fatty acid esters extractable from cuticle of honey bee larvae that communicates the presence of larvae in a colony. Honey bee brood pheromone has been shown to increase protein supplement consumption and growth of honey bee colonies in a subtropical winter climate. Here, we tested the hypothesis that synthetic brood pheromone (SuperBoost) has the potential to increase protein supplement consumption during fall in a temperate climate and thus increase colony growth. The experiments were conducted in two locations in Oregon during September and October 2009. In both the experiments, colonies receiving brood pheromone treatment consumed significantly higher protein supplement and had greater brood area and adult bees than controls. Results from this study suggest that synthetic brood pheromone may be used to stimulate honey bee colony growth by stimulating protein supplement consumption during fall in a northern temperate climate, when majority of the beekeepers feed protein supplement to their colonies.

  2. Pheromone-modulated behavioral suites influence colony growth in the honey bee (Apis mellifera)

    Science.gov (United States)

    Pankiw, Tanya; Roman, Roman; Sagili, Ramesh R.; Zhu-Salzman, Keyan

    2004-12-01

    The success of a species depends on its ability to assess its environment and to decide accordingly which behaviors are most appropriate. Many animal species, from bacteria to mammals, are able to communicate using interspecies chemicals called pheromones. In addition to exerting physiological effects on individuals, for social species, pheromones communicate group social structure. Communication of social structure is important to social insects for the allocation of its working members into coordinated suites of behaviors. We tested effects of long-term treatment with brood pheromone on suites of honey bee brood rearing and foraging behaviors. Pheromone-treated colonies reared significantly greater brood areas and more adults than controls, while amounts of stored pollen and honey remained statistically similar. Brood pheromone increased the number of pollen foragers and the pollen load weights they returned. It appeared that the pheromone-induced increase in pollen intake was directly canalized into more brood rearing. A two-way pheromone priming effect was observed, such that some workers from the same age cohorts showed an increased and extended capacity to rear larvae, while others were recruited at significantly younger ages into pollen-specific foraging. Brood pheromone affected suites of nursing and foraging behaviors allocating worker and pollen resources associated with an important fitness trait, colony growth.

  3. Mammalian pheromones.

    Science.gov (United States)

    Liberles, Stephen D

    2014-01-01

    Mammalian pheromones control a myriad of innate social behaviors and acutely regulate hormone levels. Responses to pheromones are highly robust, reproducible, and stereotyped and likely involve developmentally predetermined neural circuits. Here, I review several facets of pheromone transduction in mammals, including (a) chemosensory receptors and signaling components of the main olfactory epithelium and vomeronasal organ involved in pheromone detection; (b) pheromone-activated neural circuits subject to sex-specific and state-dependent modulation; and (c) the striking chemical diversity of mammalian pheromones, which range from small, volatile molecules and sulfated steroids to large families of proteins. Finally, I review (d) molecular mechanisms underlying various behavioral and endocrine responses, including modulation of puberty and estrous; control of reproduction, aggression, suckling, and parental behaviors; individual recognition; and distinguishing of own species from predators, competitors, and prey. Deconstruction of pheromone transduction mechanisms provides a critical foundation for understanding how odor response pathways generate instinctive behaviors.

  4. Pigment-Dispersing Factor Modulates Pheromone Production in Clock Cells that Influence Mating in Drosophila

    NARCIS (Netherlands)

    Krupp, Joshua J.; Billeter, Jean-Christophe; Wong, Amy; Choi, Charles; Nitabach, Michael N.; Levine, Joel D.

    2013-01-01

    Social cues contribute to the circadian entrainment of physiological and behavioral rhythms. These cues supplement the influence of daily and seasonal cycles in light and temperature. In Drosophila, the social environment modulates circadian mechanisms that regulate sex pheromone production and mati

  5. Drosophila adult and larval pheromones modulate larval food choice.

    Science.gov (United States)

    Farine, Jean-Pierre; Cortot, Jérôme; Ferveur, Jean-François

    2014-06-07

    Insects use chemosensory cues to feed and mate. In Drosophila, the effect of pheromones has been extensively investigated in adults, but rarely in larvae. The colonization of natural food sources by Drosophila buzzatii and Drosophila simulans species may depend on species-specific chemical cues left in the food by larvae and adults. We identified such chemicals in both species and measured their influence on larval food preference and puparation behaviour. We also tested compounds that varied between these species: (i) two larval volatile compounds: hydroxy-3-butanone-2 and phenol (predominant in D. simulans and D. buzzatii, respectively), and (ii) adult cuticular hydrocarbons (CHs). Drosophila buzzatii larvae were rapidly attracted to non-CH adult conspecific cues, whereas D. simulans larvae were strongly repulsed by CHs of the two species and also by phenol. Larval cues from both species generally reduced larval attraction and pupariation on food, which was generally--but not always--low, and rarely reflected larval response. As these larval and adult pheromones specifically influence larval food search and the choice of a pupariation site, they may greatly affect the dispersion and survival of Drosophila species in nature.

  6. An alarm pheromone modulates appetitive olfactory learning in the honeybee (Apis mellifera

    Directory of Open Access Journals (Sweden)

    Elodie Urlacher

    2010-08-01

    Full Text Available In honeybees, associative learning is embedded in a social context as bees possess a highly complex social organization in which communication among individuals is mediated by dance behavior informing about food sources, and by a high variety of pheromones that maintain the social links between individuals of a hive. Proboscis extension response (PER conditioning is a case of appetitive learning, in which harnessed bees learn to associate odor stimuli with sucrose reward in the laboratory. Despite its recurrent use as a tool for uncovering the behavioral, cellular and molecular bases underlying associative learning, the question of whether social signals (pheromones affect appetitive learning has not been addressed in this experimental framework. This situation contrasts with reports underlining that foraging activity of bees is modulated by alarm pheromones released in the presence of a potential danger. Here, we show that appetitive learning is impaired by the sting alarm pheromone (SAP which, when released by guards, recruits foragers to defend the hive. This effect is mimicked by the main component of SAP, isopentyl acetate (IPA, is dose-dependent and lasts up to 24h. Learning impairment is specific to alarm signal exposure and is independent of the odorant used for conditioning. Our results suggest that learning impairment may be a response to the biological significance of SAP as an alarm signal, which would detract bees from responding to any appetitive stimuli in a situation in which such responses would be of secondary importance.

  7. An alarm pheromone modulates appetitive olfactory learning in the honeybee (apis mellifera).

    Science.gov (United States)

    Urlacher, Elodie; Francés, Bernard; Giurfa, Martin; Devaud, Jean-Marc

    2010-01-01

    In honeybees, associative learning is embedded in a social context as bees possess a highly complex social organization in which communication among individuals is mediated by dance behavior informing about food sources, and by a high variety of pheromones that maintain the social links between individuals of a hive. Proboscis extension response conditioning is a case of appetitive learning, in which harnessed bees learn to associate odor stimuli with sucrose reward in the laboratory. Despite its recurrent use as a tool for uncovering the behavioral, cellular, and molecular bases underlying associative learning, the question of whether social signals (pheromones) affect appetitive learning has not been addressed in this experimental framework. This situation contrasts with reports underlining that foraging activity of bees is modulated by alarm pheromones released in the presence of a potential danger. Here, we show that appetitive learning is impaired by the sting alarm pheromone (SAP) which, when released by guards, recruits foragers to defend the hive. This effect is mimicked by the main component of SAP, isopentyl acetate, is dose-dependent and lasts up to 24 h. Learning impairment is specific to alarm signal exposure and is independent of the odorant used for conditioning. Our results suggest that learning impairment may be a response to the biological significance of SAP as an alarm signal, which would detract bees from responding to any appetitive stimuli in a situation in which such responses would be of secondary importance.

  8. Rapid evolution of plethodontid modulating factor, a hypervariable salamander courtship pheromone, is driven by positive selection.

    Science.gov (United States)

    Palmer, Catherine A; Watts, Richard A; Hastings, Amy P; Houck, Lynne D; Arnold, Stevan J

    2010-05-01

    Sexual communication in plethodontid salamanders is mediated by a proteinaceous pheromone that a male delivers to a female during courtship, boosting her receptivity. The pheromone consists of three proteins from three unrelated protein families. These proteins are among a small group of pheromones known to affect female receptivity in vertebrates. Previously, we showed that the genes of two of these proteins (PRF and SPF) are prone to incessant evolution driven by positive selection, presumably as a consequence of coevolution with female receptors. In this report, we focus on the evolution of the third pheromone protein gene family, plethodontid modulating factor (PMF), to determine whether it shows the same pattern of diversification. We used RT-PCR in mental gland cDNA to survey PMF sequences from three genera of plethodontid salamanders (27 spp.) to measure rates of evolution, level of gene diversification, modes of selection, and types of amino acid substitution. Like PRF and SPF, PMF is produced by a multigene family characterized by gene duplication and high levels of polymorphism. PMF evolution is rapid, incessant, and driven by positive selection. PMF is more extreme in these dimensions than both PRF and SPF. Nestled within this extraordinary variation, however, is a signature of purifying selection, acting to preserve important structural and biochemical features of the PMF protein (i.e., secretion signal, cysteine residues, and pI). Although a pattern of persistent diversification exists at the molecular level, the morphological and behavioral aspects of the pheromone delivery system show evolutionary stasis over millions of years.

  9. Effects of Protein-pheromone Complexation on Correlated Chemical Shift Modulations

    Energy Technology Data Exchange (ETDEWEB)

    Perazzolo, Chiara; Wist, Julien [Ecole Polytechnique Federale de Lausanne, Institut des Sciences et Ingenierie Chimiques (Switzerland); Loth, Karine; Poggi, Luisa [Ecole Normale Superieure, Departement de chimie, associe au CNRS (France); Homans, Steve [University of Leeds, School of Biochemistry and Microbiology (United Kingdom); Bodenhausen, Geoffrey [Ecole Polytechnique Federale de Lausanne, Institut des Sciences et Ingenierie Chimiques (Switzerland)], E-mail: Geoffrey.Bodenhausen@ens.fr

    2005-12-15

    Major urinary protein (MUP) is a pheromone-carrying protein of the lipocalin family. Previous studies by isothermal titration calorimetry (ITC) show that the affinity of MUP for the pheromone 2-methoxy-3-isobutylpyrazine (IBMP) is mainly driven by enthalpy, with a small unfavourable entropic contribution. Entropic terms can be attributed in part to changes in internal motions of the protein upon binding. Slow internal motions can lead to correlated or anti-correlated modulations of the isotropic chemical shifts of carbonyl C' and amide N nuclei. Correlated chemical shift modulations (CSM/CSM) in MUP have been determined by measuring differences of the transverse relaxation rates of zero- and double-quantum coherences ZQC{l_brace}C'N{r_brace} and DQC{l_brace}C'N{r_brace}, and by accounting for the effects of correlated fluctuations of dipole-dipole couplings (DD/DD) and chemical shift anisotropies (CSA/CSA). The latter can be predicted from tensor parameters of C' and N nuclei that have been determined in earlier work. The effects of complexation on slow time-scale protein dynamics can be determined by comparing the temperature dependence of the relaxation rates of APO-MUP (i.e., without ligand) and HOLO-MUP (i.e., with IBMP as a ligand)

  10. Alarm pheromone does not modulate 22-kHz calls in male rats.

    Science.gov (United States)

    Muyama, Hiromi; Kiyokawa, Yasushi; Inagaki, Hideaki; Takeuchi, Yukari; Mori, Yuji

    2016-03-15

    Rats are known to emit a series of ultrasonic vocalizations, termed 22-kHz calls, when exposed to distressing stimuli. Pharmacological studies have indicated that anxiety mediates 22-kHz calls in distressed rats. We previously found that exposure to the rat alarm pheromone increases anxiety in rats. Therefore, we hypothesized that the alarm pheromone would increase 22-kHz calls in pheromone-exposed rats. Accordingly, we tested whether exposure to the alarm pheromone induced 22-kHz calls, as well as whether the alarm pheromone increased 22-kHz calls in response to an aversive conditioned stimulus (CS). Rats were first fear-conditioned to an auditory and contextual CS. On the following day, the rats were either exposed to the alarm pheromone or a control odor that was released from the neck region of odor-donor rats. Then, the rats were re-exposed to the aversive CS. The alarm pheromone neither induced 22-kHz calls nor increased 22-kHz calls in response to the aversive CS. In contrast, the control odor unexpectedly reduced the total number and duration of 22-kHz calls elicited by the aversive CS, as well as the duration of freezing. These results suggest that the alarm pheromone does not affect 22-kHz calls in rats. However, we may have found evidence for an appeasing olfactory signal, released from the neck region of odor-donor rats.

  11. Queen pheromones modulate DNA methyltransferase activity in bee and ant workers.

    Science.gov (United States)

    Holman, Luke; Trontti, Kalevi; Helanterä, Heikki

    2016-01-01

    DNA methylation is emerging as an important regulator of polyphenism in the social insects. Research has concentrated on differences in methylation between queens and workers, though we hypothesized that methylation is involved in mediating other flexible phenotypes, including pheromone-dependent changes in worker behaviour and physiology. Here, we find that exposure to queen pheromone affects the expression of two DNA methyltransferase genes in Apis mellifera honeybees and in two species of Lasius ants, but not in Bombus terrestris bumblebees. These results suggest that queen pheromones influence the worker methylome, pointing to a novel proximate mechanism for these key social signals.

  12. An aggregation pheromone modulates lekking behavior in the vector mosquito Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Cabrera, Maira; Jaffe, Klaus

    2007-03-01

    Males of Aedes aegypti mosquitoes formed swarms in the laboratory, triggered by the onset of the photophase or by the presence of odors from a rat (which is a potential host for females). The swarm attracted both males and females and increased mating activity. The number of copulas per mosquito was positively correlated with the number of mosquitoes in the swarm and with the duration of the swarm. Swarming and mating activity increased with the presence of a host for females. Young sexually immature males, less than 24 h old, flew but did not swarm nor copulate. Observations using an olfactometer showed that swarming males produced a volatile pheromone that stimulates the flying activity of females at a distance. Females also produce a volatile attractant. The results suggest that males, and possibly also females, produce an aggregation pheromone that attracts males and females towards the swarm. The characteristics of the pheromone-mediated swarm may be described as a 3-dimensional lek. Our results suggest that the development of pheromone-based control systems and/or pheromone traps for the monitoring of vector populations is feasible, adding a new tool to combat this vector of several human pathogens.

  13. Multimodal stimulation of Colorado potato beetle reveals modulation of pheromone response by yellow light.

    Directory of Open Access Journals (Sweden)

    Fernando Otálora-Luna

    Full Text Available Orientation of insects to host plants and conspecifics is the result of detection and integration of chemical and physical cues present in the environment. Sensory organs have evolved to be sensitive to important signals, providing neural input for higher order multimodal processing and behavioral output. Here we report experiments to determine decisions made by Colorado potato beetle (CPB, Leptinotarsa decemlineata, in response to isolated stimuli and multimodal combinations of signals on a locomotion compensator. Our results show that in complete darkness and in the absence of other stimuli, pheromonal stimulation increases attraction behavior of CPB as measured in oriented displacement and walking speed. However, orientation to the pheromone is abolished when presented with the alternative stimulation of a low intensity yellow light in a dark environment. The ability of the pheromone to stimulate these diurnal beetles in the dark in the absence of other stimuli is an unexpected but interesting observation. The predominance of the phototactic response over that to pheromone when low intensity lights were offered as choices seems to confirm the diurnal nature of the insect. The biological significance of the response to pheromone in the dark is unclear. The phototactic response will play a key role in elucidating multimodal stimulation in the host-finding process of CPB, and perhaps other insects. Such information might be exploited in the design of applications to attract and trap CPB for survey or control purposes and other insect pests using similar orientation mechanisms.

  14. Pheromone Signalling

    Science.gov (United States)

    Hart, Adam G.

    2011-01-01

    Pheromones are chemicals used to communicate with members of the same species. First described in insects, pheromones are often used to attract mates but in social insects, such as ants and bees, pheromone use is much more sophisticated. For example, ants use pheromones to make foraging trails and the chemical and physical properties of the…

  15. A carboxylesterase, Esterase-6, modulates sensory physiological and behavioral response dynamics to pheromone in Drosophila

    Directory of Open Access Journals (Sweden)

    Chertemps Thomas

    2012-06-01

    Full Text Available Abstract Background Insects respond to the spatial and temporal dynamics of a pheromone plume, which implies not only a strong response to 'odor on', but also to 'odor off'. This requires mechanisms geared toward a fast signal termination. Several mechanisms may contribute to signal termination, among which odorant-degrading enzymes. These enzymes putatively play a role in signal dynamics by a rapid inactivation of odorants in the vicinity of the sensory receptors, although direct in vivo experimental evidences are lacking. Here we verified the role of an extracellular carboxylesterase, esterase-6 (Est-6, in the sensory physiological and behavioral dynamics of Drosophila melanogaster response to its pheromone, cis-vaccenyl acetate (cVA. Est-6 was previously linked to post-mating effects in the reproductive system of females. As Est-6 is also known to hydrolyze cVA in vitro and is expressed in the main olfactory organ, the antenna, we tested here its role in olfaction as a putative odorant-degrading enzyme. Results We first confirm that Est-6 is highly expressed in olfactory sensilla, including cVA-sensitive sensilla, and we show that expression is likely associated with non-neuronal cells. Our electrophysiological approaches show that the dynamics of olfactory receptor neuron (ORN responses is strongly influenced by Est-6, as in Est-6° null mutants (lacking the Est-6 gene cVA-sensitive ORN showed increased firing rate and prolonged activity in response to cVA. Est-6° mutant males had a lower threshold of behavioral response to cVA, as revealed by the analysis of two cVA-induced behaviors. In particular, mutant males exhibited a strong decrease of male-male courtship, in association with a delay in courtship initiation. Conclusions Our study presents evidence that Est-6 plays a role in the physiological and behavioral dynamics of sex pheromone response in Drosophila males and supports a role of Est-6 as an odorant-degrading enzyme (ODE in male

  16. Pheromone reception in mammals.

    Science.gov (United States)

    Bigiani, A; Mucignat-Caretta, C; Montani, G; Tirindelli, R

    2005-01-01

    other members of the same species. Therefore, the action of an organism can alter the behavior of another organism, thereby increasing the fitness of either or both. Albeit slow in transmission and not easily modulated, pheromones can travel around objects in the dark and over long distances. In addition, they are emitted when necessary and their biosynthesis is usually economic. In essence, they represent the most efficient tool to refine the pattern of social behaviors and reproductive strategies.

  17. [Synergism of plant volatiles to insect pheromones and related mechanisms].

    Science.gov (United States)

    Wang, Zhen-hua; Zhao, Hui; Li, Jin-fu; Zeng, Xian-dong; Chen, Jian-jun; Feng, Han-li; Xu, Jia-wen

    2008-11-01

    Host plant volatiles and insect pheromones are the most important semiochemicals for insects, and their synergism can modulate insect behaviors. The attraction to sex- and aggregation pheromones of insects can be greatly enhanced by specific plant volatiles through the increased electroantennogram, pheromone incepting neuron action potential, and pulse-frequency. When the specific plant volatiles are bound with octopamine receptors, the threshold of sex pheromone incepting neuron to sex pheromones is decreased, while the sensibility of sex pheromone incepting neuron is increased, which may be the main mechanism for the synergism of plant volatiles to insect pheromones.

  18. Aphid pheromones.

    Science.gov (United States)

    Dewhirst, Sarah Y; Pickett, John A; Hardie, Jim

    2010-01-01

    Aphids are the main insect pests of agricultural crops in temperate regions causing major economic losses. Although broad-spectrum insecticides are available for control, alternative and more targeted methods are needed due to insecticide resistance and increasing environmental pressures. An alternative control method for aphids is to exploit their pheromones, which have been extensively studied in recent years. For example, aphids release alarm pheromones in response to natural enemy attack and these could be used to deter aphids from the crops. Sex pheromones have also been identified which could be used to interfere males locating conspecific females (oviparae), as well as for manipulating natural enemies. Several hypotheses relating to how species integrity is maintained via the aphid sex pheromone have been proposed. The composition and behavioral activity of these pheromones, and how their use could be implemented in integrated pest management systems to control aphids, is discussed.

  19. Larval salivary glands are a source of primer and releaser pheromone in honey bee ( Apis mellifera L.)

    Science.gov (United States)

    Conte, Yves Le; Bécard, Jean-Marc; Costagliola, Guy; de Vaublanc, Gérard; Maâtaoui, Mohamed El; Crauser, Didier; Plettner, Erika; Slessor, Keith N.

    2006-05-01

    A brood pheromone identified in honeybee larvae has primer and releaser pheromone effects on adult bees. Using gas chromatography-mass spectrometry (GC-MS) to evaluate fatty acid esters—the pheromonal compounds—in different parts of the larvae, we have localized the source of the esters as the larval salivary glands. A histochemical study describes the glands and confirms the presence of lipids in the glands. Epithelial cells of the gland likely secrete the fatty acids into the lumen of the gland. These results demonstrate the salivary glands to be a reservoir of esters, components of brood pheromone, in honeybee larvae.

  20. Modulation of the adrenocortical response to acute stress with respect to brood value, reproductive success and survival in the Eurasian hoopoe.

    Science.gov (United States)

    Schmid, Baptiste; Tam-Dafond, Laura; Jenni-Eiermann, Susanne; Arlettaz, Raphaël; Schaub, Michael; Jenni, Lukas

    2013-09-01

    Reproducing parents face the difficult challenge of trading-off investment in current reproduction against presumed future survival and reproduction. Glucocorticoids are supposed to mediate this trade-off because the adrenocortical response to stress disrupts normal reproductive behaviour in favour of self-maintenance and own survival. According to the brood-value hypothesis, individuals with a low survival probability until the next reproductive season have to invest in current reproduction, a process driven by a down-regulation of their adrenocortical response. If the adrenocortical response to stress effectively mediates the trade-off between current reproduction versus future survival and reproduction, we expect a negative relationship with reproductive success and a positive correlation of the adrenocortical stress response with survival. We studied the relationship between corticosterone secretion in parents and their current brood value, reproductive success and survival in a short-lived multi-brooded bird, the Eurasian hoopoe Upupa epops. The adrenocortical response to acute handling stress was correlated with the brood value within the individual (first and second broods of the year) and between individuals. Birds breeding late in the season mounted a lower total corticosterone response to acute stress than birds breeding earlier, while females showed lower levels than males. We observed a negative relationship between the adrenocortical stress response and rearing success or fledging success in females, as predicted by the brood-value hypothesis. However, we could not evidence a clear link between the adrenocortical stress response and survival. Future research testing the brood-value hypothesis and trade-offs between current reproduction and future survival should also measure free corticosterone and carefully differentiate between cross-sectional (i.e. between-individual) and individual-based experimental studies.

  1. The role of the RACK1 ortholog Cpc2p in modulating pheromone-induced cell cycle arrest in fission yeast.

    Directory of Open Access Journals (Sweden)

    Magdalena Mos

    Full Text Available The detection and amplification of extracellular signals requires the involvement of multiple protein components. In mammalian cells the receptor of activated C kinase (RACK1 is an important scaffolding protein for signal transduction networks. Further, it also performs a critical function in regulating the cell cycle by modulating the G1/S transition. Many eukaryotic cells express RACK1 orthologs, with one example being Cpc2p in the fission yeast Schizosaccharomyces pombe. In contrast to RACK1, Cpc2p has been described to positively regulate, at the ribosomal level, cells entry into M phase. In addition, Cpc2p controls the stress response pathways through an interaction with Msa2p, and sexual development by modulating Ran1p/Pat1p. Here we describe investigations into the role, which Cpc2p performs in controlling the G protein-mediated mating response pathway. Despite structural similarity to Gβ-like subunits, Cpc2p appears not to function at the G protein level. However, upon pheromone stimulation, cells overexpressing Cpc2p display substantial cell morphology defects, disorientation of septum formation and a significantly protracted G1 arrest. Cpc2p has the potential to function at multiple positions within the pheromone response pathway. We provide a mechanistic interpretation of this novel data by linking Cpc2p function, during the mating response, with its previous described interactions with Ran1p/Pat1p. We suggest that overexpressing Cpc2p prolongs the stimulated state of pheromone-induced cells by increasing ste11 gene expression. These data indicate that Cpc2p regulates the pheromone-induced cell cycle arrest in fission yeast by delaying cells entry into S phase.

  2. Pheromonal regulation of starvation resistance in honey bee workers ( Apis mellifera)

    Science.gov (United States)

    Fischer, Patrick; Grozinger, Christina M.

    2008-08-01

    Most animals can modulate nutrient storage pathways according to changing environmental conditions, but in honey bees nutrient storage is also modulated according to changing behavioral tasks within a colony. Specifically, bees involved in brood care (nurses) have higher lipid stores in their abdominal fat bodies than forager bees. Pheromone communication plays an important role in regulating honey bee behavior and physiology. In particular, queen mandibular pheromone (QMP) slows the transition from nursing to foraging. We tested the effects of QMP exposure on starvation resistance, lipid storage, and gene expression in the fat bodies of worker bees. We found that indeed QMP-treated bees survived much longer compared to control bees when starved and also had higher lipid levels. Expression of vitellogenin RNA, which encodes a yolk protein that is found at higher levels in nurses than foragers, was also higher in the fat bodies of QMP-treated bees. No differences were observed in expression of genes involved in insulin signaling pathways, which are associated with nutrient storage and metabolism in a variety of species; thus, other mechanisms may be involved in increasing the lipid stores. These studies demonstrate that pheromone exposure can modify nutrient storage pathways and fat body gene expression in honey bees and suggest that chemical communication and social interactions play an important role in altering metabolic pathways.

  3. Differential combinatorial coding of pheromones in two olfactory subsystems of the honey bee brain.

    Science.gov (United States)

    Carcaud, Julie; Giurfa, Martin; Sandoz, Jean-Christophe

    2015-03-11

    Neural coding of pheromones has been intensively studied in insects with a particular focus on sex pheromones. These studies favored the view that pheromone compounds are processed within specific antennal lobe glomeruli following a specialized labeled-line system. However, pheromones play crucial roles in an insect's life beyond sexual attraction, and some species use many different pheromones making such a labeled-line organization unrealistic. A combinatorial coding scheme, in which each component activates a set of broadly tuned units, appears more adapted in this case. However, this idea has not been tested thoroughly. We focused here on the honey bee Apis mellifera, a social insect that relies on a wide range of pheromones to ensure colony cohesion. Interestingly, the honey bee olfactory system harbors two central parallel pathways, whose functions remain largely unknown. Using optophysiological recordings of projection neurons, we compared the responses of these two pathways to 27 known honey bee pheromonal compounds emitted by the brood, the workers, and the queen. We show that while queen mandibular pheromone is processed by l-ALT (lateral antennal lobe tract) neurons and brood pheromone is mainly processed by m-ALT (median antennal lobe tract) neurons, worker pheromones induce redundant activity in both pathways. Moreover, all tested pheromonal compounds induce combinatorial activity from several AL glomeruli. These findings support the combinatorial coding scheme and suggest that higher-order brain centers reading out these combinatorial activity patterns may eventually classify olfactory signals according to their biological meaning.

  4. Pollination by brood-site deception.

    Science.gov (United States)

    Urru, Isabella; Stensmyr, Marcus C; Hansson, Bill S

    2011-09-01

    Pollination is often regarded as a mutualistic relationship between flowering plants and insects. In such a relationship, both partners gain a fitness benefit as a result of their interaction. The flower gets pollinated and the insect typically gets a food-related reward. However, flower-insect communication is not always a mutualistic system, as some flowers emit deceitful signals. Insects are thus fooled by irresistible stimuli and pollination is accomplished. Such deception requires very fine tuning, as insects in their typically short life span, try to find mating/feeding breeding sites as efficiently as possible, and following deceitful signals thus is both costly and time-consuming. Deceptive flowers have thus evolved the ability to emit signals that trigger obligate innate or learned responses in the targeted insects. The behavior, and thus the signals, exploited are typically involved in reproduction, from attracting pheromones to brood/food-site cues. Chemical mimicry is one of the main modalities through which flowers trick their pollen vectors, as olfaction plays a pivotal role in insect-insect and insect-plant interactions. Here we focus on floral odors that specifically mimic an oviposition substrate, i.e., brood-site mimicry. The phenomenon is wide spread across unrelated plant lineages of Angiosperm, Splachnaceae and Phallaceae. Targeted insects are mainly beetles and flies, and flowers accordingly often emit, to the human nose, highly powerful and fetid smells that are conversely extremely attractive to the duped insects. Brood-site deceptive plants often display highly elaborate flowers and have evolved a trap-release mechanism. Chemical cues often act in unison with other sensory cues to refine the imitation.

  5. An experimental test of the effect of brood size on glucocorticoid responses, parental investment, and offspring phenotype.

    Science.gov (United States)

    Vitousek, Maren N; Jenkins, Brittany R; Hubbard, Joanna K; Kaiser, Sara A; Safran, Rebecca J

    2017-01-28

    Because elevated glucocorticoid levels can impair reproduction, populations or species that engage in particularly valuable reproductive attempts may down-regulate the glucocorticoid stress response during reproduction (the brood value hypothesis). It is not clear, however, whether individuals rapidly modulate glucocorticoid responses based on shifting cues about the likelihood of reproductive success. By manipulating brood size to create broods that differed in potential value, we tested whether female barn swallows (Hirundo rustica) rapidly modulated the glucocorticoid stress response to promote investment in high-value broods, and whether nestling phenotype was influenced by treatment. Within-individual changes in female corticosterone, body mass, and measures of oxidative stress were unrelated to brood size treatment. Standard offspring provisioning rate did not differ across treatments; however, in the presence of a model predator, females raising enlarged broods maintained higher offspring feeding rates relative to control broods. Brood size did influence nestling phenotype. Nestlings from enlarged broods had lower body mass and higher baseline corticosterone than those from reduced broods. Finally, in adult females both baseline and stress-induced corticosterone were individually repeatable. Thus, while under moderately challenging environmental conditions brood size manipulations had context-dependent effects on parental investment, and influenced nestling phenotype, maternal glucocorticoid levels were not modulated based on brood value but were individually consistent features of phenotype during breeding.

  6. Woodcock brood ecology in Maine

    Science.gov (United States)

    Dwyer, T.J.; Derleth, E.L.; McAuley, D.G.

    1982-01-01

    Captures of 102 American woodcock (Philohela minor) broods, including 338 chicks, from 1977 to 1980 provided data on age-related production by breeding females and on growth and survival of chicks. Although broods of second-year females are smaller and hatch at slightly later dates and the growth of the chicks is slower than that of broods of after-second-year hens, we could detect no difference in survival of the chicks. Yearly variation in the sex ratio of fledged young was probably the result of selection for or against larger female chicks during different environmental conditions. Broodmates associate with each other throughout the summer, and there are differences in habitat preferences between young (1-5 days old) and older (> 5 days old) broods. Older broods prefer more open, mature forest stands with fewer trees per hectare.

  7. Varroa Sensitive Hygiene and Drone Brood

    Science.gov (United States)

    Honey bees have been bred to express high levels of varroa sensitive hygiene (VSH), which is the removal of mite-infested pupae from capped worker brood. This hygienic behavior is a complex interaction of bees and brood in which brood cells sometimes are inspected, and then brood is either removed (...

  8. The main component of an alarm pheromone of kissing bugs plays multiple roles in the cognitive modulation of the escape response

    Directory of Open Access Journals (Sweden)

    Sebastián eMinoli

    2013-07-01

    Full Text Available Innate responses in animals can be modulated by experience. Disturbed adults of the triatomine bug Triatoma infestans release an alarm pheromone (AP that elicits an escape response in conspecific larvae. The main component of this AP, the isobutyric acid (IsoAc, alone has already shown to generate an escape response in this species. However, not much is known about the modulation of this behavior by non-associative and associative cognitive processes. We present here evidences of the cognitive capacities of T. infestans larvae in an escape context under different conditioning paradigms, including IsoAc in different roles. We show that: 1 the duration of a pre-exposure to IsoAc plays a main role in determining the type of non-associative learning expressed: short time pre-exposures elicit a sensitization while a longer pre-exposure time triggers a switch from repellence to attractiveness; 2 a simple pre-exposure event is enough to modulate the escape response of larvae to the AP and to its main component: IsoAc; 3 IsoAc and the AP are perceived as different chemical entities; 4 an association between IsoAc and an aversive stimulus can be created under a classical conditioning paradigm; 5 an association between IsoAc and a self-action can be generated under an operant conditioning. These results evince that IsoAc can attain multiple and different cognitive roles in the modulation of the escape response of triatomines and show how cognitive processes can modulate a key behavior for surviving, as it is the escaping response in presence of a potential danger in insects.

  9. Uncoupling primer and releaser responses to pheromone in honey bees

    Science.gov (United States)

    Grozinger, Christina M.; Fischer, Patrick; Hampton, Jacob E.

    2007-05-01

    Pheromones produce dramatic behavioral and physiological responses in a wide variety of species. Releaser pheromones elicit rapid responses within seconds or minutes, while primer pheromones produce long-term changes which may take days to manifest. Honeybee queen mandibular pheromone (QMP) elicits multiple distinct behavioral and physiological responses in worker bees, as both a releaser and primer, and thus produces responses on vastly different time scales. In this study, we demonstrate that releaser and primer responses to QMP can be uncoupled. First, treatment with the juvenile hormone analog methoprene leaves a releaser response (attraction to QMP) intact, but modulates QMP’s primer effects on sucrose responsiveness. Secondly, two components of QMP (9-ODA and 9-HDA) do not elicit a releaser response (attraction) but are as effective as QMP at modulating a primer response, downregulation of foraging-related brain gene expression. These results suggest that different responses to a single pheromone may be produced via distinct pathways.

  10. How mammals detect pheromones.

    Science.gov (United States)

    Silvotti, L; Montani, G; Tirindelli, R

    2003-01-01

    One of the most intriguing discoveries in mammalian pheromone research is the report that a short exposure of women to volatile compounds from sweat can significantly alter their menstrual cycle. This work suggests that specific molecules are produced by women at different stages of the menstrual cycle and that this putative 'pheromonal' blend has effects on the timing of the cycle in women that were briefly exposed to it. What human pheromones are and how they work are not known, however a considerable progress has been made in understanding how other mammals are likely to detect pheromones with the discovery of pheromone receptors. Even though it is proved that pheromones affect human responses, it remains unlikely that similar receptors account for these effects.

  11. The pheromone emergency

    Science.gov (United States)

    Female moths utilize sex pheromones to attract mates across a potentially long geographic distance. The biochemical basis of how moth female sex pheromones are synthesized has been elucidated in a number of species, and a particularly large amount of effort has been expended on the agricultural pes...

  12. Peripheral, central and behavioral responses to the cuticular pheromone bouquet in Drosophila melanogaster males.

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Inoshita

    Full Text Available Pheromonal communication is crucial with regard to mate choice in many animals including insects. Drosophila melanogaster flies produce a pheromonal bouquet with many cuticular hydrocarbons some of which diverge between the sexes and differently affect male courtship behavior. Cuticular pheromones have a relatively high weight and are thought to be -- mostly but not only -- detected by gustatory contact. However, the response of the peripheral and central gustatory systems to these substances remains poorly explored. We measured the effect induced by pheromonal cuticular mixtures on (i the electrophysiological response of peripheral gustatory receptor neurons, (ii the calcium variation in brain centers receiving these gustatory inputs and (iii the behavioral reaction induced in control males and in mutant desat1 males, which show abnormal pheromone production and perception. While male and female pheromones induced inhibitory-like effects on taste receptor neurons, the contact of male pheromones on male fore-tarsi elicits a long-lasting response of higher intensity in the dedicated gustatory brain center. We found that the behavior of control males was more strongly inhibited by male pheromones than by female pheromones, but this difference disappeared in anosmic males. Mutant desat1 males showed an increased sensitivity of their peripheral gustatory neurons to contact pheromones and a behavioral incapacity to discriminate sex pheromones. Together our data indicate that cuticular hydrocarbons induce long-lasting inhibitory effects on the relevant taste pathway which may interact with the olfactory pathway to modulate pheromonal perception.

  13. Pheromones: a new ergogenic aid in sport?

    Science.gov (United States)

    Papaloucas, Marios; Kyriazi, Kyriaki; Kouloulias, Vassilis

    2015-10-01

    Nowadays, antidoping laboratories are improving detection methods to confirm the use of forbidden substances. These tests are based both on direct identification of new substances or their metabolites and on indirect evaluation of changes in gene, protein, or metabolite patterns (genomics, proteomics, or metabolomics). The World Anti-Doping Agency (WADA) officially monitors anabolic steroids, hormones, growth factors, β-agonists, hormone and metabolic modulators, masking agents, street drugs, manipulation of blood and blood components, chemical and physical manipulation, gene doping, stimulants, narcotics, glucocorticosteroids, and β-blockers. However, several other substances are under review by WADA. Pheromones accomplish the structure and function of life from its first step, while they have an impact on the body's performance. Both testosterone and pheromones have an ergogenic effect that could potentially affect an athlete's performance. The authors share their questions concerning the potential impact of pheromones in sports.

  14. Sensory reception of the primer pheromone ethyl oleate

    Science.gov (United States)

    Muenz, Thomas S.; Maisonnasse, Alban; Plettner, Erika; Le Conte, Yves; Rössler, Wolfgang

    2012-05-01

    Social work force distribution in honeybee colonies critically depends on subtle adjustments of an age-related polyethism. Pheromones play a crucial role in adjusting physiological and behavioral maturation of nurse bees to foragers. In addition to primer effects of brood pheromone and queen mandibular pheromone—both were shown to influence onset of foraging—direct worker-worker interactions influence adult behavioral maturation. These interactions were narrowed down to the primer pheromone ethyl oleate, which is present at high concentrations in foragers, almost absent in young bees and was shown to delay the onset of foraging. Based on chemical analyses, physiological recordings from the antenna (electroantennograms) and the antennal lobe (calcium imaging), and behavioral assays (associative conditioning of the proboscis extension response), we present evidence that ethyl oleate is most abundant on the cuticle, received by olfactory receptors on the antenna, processed in glomeruli of the antennal lobe, and learned in olfactory centers of the brain. The results are highly suggestive that the primer pheromone ethyl oleate is transmitted and perceived between individuals via olfaction at close range.

  15. Facts, fallacies, fears, and frustrations with human pheromones.

    Science.gov (United States)

    Wysocki, Charles J; Preti, George

    2004-11-01

    Among primates in general, pheromones are of variable importance to social communication. Data on humans have generated the greatest controversy regarding the existence of pheromonal communication. In this review, the likelihood of pheromonal communication in humans is assessed with a discussion of chemical compounds produced by the axilla that may function as pheromones; the likelihood that the vomeronasal organ (VNO), a putative pheromone receptor organ in many other mammals, is functional in humans; and the possible ways pheromones operate in humans. In the human axilla, the interactions between the cutaneous microflora and axillary secretions render this region analogous to scent glands found in other primates. Both the chemistry of axillary secretions and their effects on conspecifics in humans appear to be analogous to other mammalian pheromone systems. Whichever chemical compounds serve a pheromonal function in humans, another unknown is the receptor. Although the VNO has been implicated in the reception of pheromones in many vertebrates, it is not the only pathway through which such information has access to the central nervous system; there is ample evidence to support the view that the olfactory epithelium can respond to pheromones. Furthermore, if a chemical activates receptors within the VNO, this does not necessarily mean that the compound is a pheromone. An important caveat for humans is that critical components typically found within the functioning VNO of other, nonprimate, mammals are lacking, suggesting that the human VNO does not function in the way that has been described for other mammals. In a broader perspective, pheromones can be classified as primers, signalers, modulators, and releasers. There is good evidence to support the presence of the former three in humans. Examples include affects on the menstrual cycle (primer effects); olfactory recognition of newborn by its mother (signaler); individuals may exude different odors based on mood

  16. Pheromones of cockroaches

    NARCIS (Netherlands)

    Persoons, C.J.; Ritter, F.J.

    1979-01-01

    The article presents a review of the bíological significance and the chemistry of several pheromones of cockroaches. The data given are in part based on our own work, and in part taken from the literature.

  17. Effect of primer pheromones and pollen diet on the food producing glands of worker honey bees (Apis mellifera L.).

    Science.gov (United States)

    Peters, Lizette; Zhu-Salzman, Keyan; Pankiw, Tanya

    2010-02-01

    Cooperative brood care is highly developed in the honey bee such that workers called nurses use their hypopharyngeal and mandibular glands to biosynthesize proteinaceous secretions that are progressively provisioned to larvae. The role that honey bee primer pheromones play in the functional physiology of food producing glands was examined. The combined and separate effects of queen mandibular pheromone (QMP) and brood pheromone (BP) on amount of protein extractable from hypopharyngeal and mandibular glands of workers reared for 12 days with and without pollen diets was measured. In rearing environments with a pollen diet, BP, and QMP+BP pheromone treatments significantly increased extractable protein from both glands. Bees reared with QMP+pollen had amounts of protein extractable from both glands that were not significantly different from control bees (no pheromones, no pollen). Pollen in the diet alone significantly increased amounts of protein extractable from glands versus control. In rearing environments without pollen, QMP+BP had a synergizing effect on amount of protein in both glands. The QMP+BP treatment was the only rearing environment without a pollen diet where protein amounts were significantly greater than the control. The synergizing effect of QMP+BP on extractable mandibular and hypopharyngeal gland protein suggests a highly derived role for the combined effect of these two primer pheromones on honey bee cooperative brood care. Mandibular gland area was significantly and positively correlated with extractable protein. Amounts of extractable protein from both glands declined significantly with age of workers in all treatments. However, treatment significantly affected rate of decline. The adaptive significance of gland protein amounts in response to pheromones and pollen diet are discussed.

  18. Sexy DEG/ENaC channels involved in gustatory detection of fruit fly pheromones.

    Science.gov (United States)

    Pikielny, Claudio W

    2012-11-06

    Hydrocarbon pheromones on the cuticle of Drosophila melanogaster modulate the complex courtship behavior of males. Recently, three members of the degenerin/epithelial Na+ channel (DEG/ENaC) family of sodium channel subunits, Ppk25, Ppk23, and Ppk29 (also known as Nope), have been shown to function in gustatory perception of courtship-modulating contact pheromones. All three proteins are required for the activation of male courtship by female pheromones. Specific interactions between two of them have been demonstrated in cultured cells, suggesting that, in a subset of cells where they are coexpressed, these three subunits function within a common heterotrimeric DEG/ENaC channel. Such a DEG/ENaC channel may be gated by pheromones, either directly or indirectly, or alternatively may control the excitability of pheromone-sensing cells. In addition, these studies identify taste neurons that respond specifically to courtship-modulating pheromones and mediate their effects on male behavior. Two types of pheromone-sensing taste neurons, F and M cells, have been defined on the basis of their specific response to either female or male pheromones. These reports set the stage for the dissection of the molecular and cellular mechanisms that mediate gustatory detection of contact pheromones.

  19. Laboratory Syntheses of Insect Pheromones.

    Science.gov (United States)

    Cormier, Russell A.; Hoban, James N.

    1984-01-01

    Provides background information and procedures for the multi-step synthesis of tiger moth and boll weevil pheromones (sex attractants). These syntheses require several laboratory periods. The tiger moth pheromone synthesis is suitable for introductory organic chemistry while the boll weevil pheromone is recommended for an advanced laboratory…

  20. Nutrient-dependent/pheromone-controlled adaptive evolution: a model

    Directory of Open Access Journals (Sweden)

    James Vaughn Kohl

    2013-06-01

    Full Text Available Background: The prenatal migration of gonadotropin-releasing hormone (GnRH neurosecretory neurons allows nutrients and human pheromones to alter GnRH pulsatility, which modulates the concurrent maturation of the neuroendocrine, reproductive, and central nervous systems, thus influencing the development of ingestive behavior, reproductive sexual behavior, and other behaviors. Methods: This model details how chemical ecology drives adaptive evolution via: (1 ecological niche construction, (2 social niche construction, (3 neurogenic niche construction, and (4 socio-cognitive niche construction. This model exemplifies the epigenetic effects of olfactory/pheromonal conditioning, which alters genetically predisposed, nutrient-dependent, hormone-driven mammalian behavior and choices for pheromones that control reproduction via their effects on luteinizing hormone (LH and systems biology. Results: Nutrients are metabolized to pheromones that condition behavior in the same way that food odors condition behavior associated with food preferences. The epigenetic effects of olfactory/pheromonal input calibrate and standardize molecular mechanisms for genetically predisposed receptor-mediated changes in intracellular signaling and stochastic gene expression in GnRH neurosecretory neurons of brain tissue. For example, glucose and pheromones alter the hypothalamic secretion of GnRH and LH. A form of GnRH associated with sexual orientation in yeasts links control of the feedback loops and developmental processes required for nutrient acquisition, movement, reproduction, and the diversification of species from microbes to man. Conclusion: An environmental drive evolved from that of nutrient ingestion in unicellular organisms to that of pheromone-controlled socialization in insects. In mammals, food odors and pheromones cause changes in hormones such as LH, which has developmental affects on pheromone-controlled sexual behavior in nutrient-dependent reproductively

  1. Pheromone production in bark beetles.

    Science.gov (United States)

    Blomquist, Gary J; Figueroa-Teran, Rubi; Aw, Mory; Song, Minmin; Gorzalski, Andrew; Abbott, Nicole L; Chang, Eric; Tittiger, Claus

    2010-10-01

    The first aggregation pheromone components from bark beetles were identified in 1966 as a mixture of ipsdienol, ipsenol and verbenol. Since then, a number of additional components have been identified as both aggregation and anti-aggregation pheromones, with many of them being monoterpenoids or derived from monoterpenoids. The structural similarity between the major pheromone components of bark beetles and the monoterpenes found in the host trees, along with the association of monoterpenoid production with plant tissue, led to the paradigm that most if not all bark beetle pheromone components were derived from host tree precursors, often with a simple hydroxylation producing the pheromone. In the 1990 s there was a paradigm shift as evidence for de novo biosynthesis of pheromone components began to accumulate, and it is now recognized that most bark beetle monoterpenoid aggregation pheromone components are biosynthesized de novo. The bark beetle aggregation pheromones are released from the frass, which is consistent with the isoprenoid aggregation pheromones, including ipsdienol, ipsenol and frontalin, being produced in midgut tissue. It appears that exo-brevocomin is produced de novo in fat body tissue, and that verbenol, verbenone and verbenene are produced from dietary α-pinene in fat body tissue. Combined biochemical, molecular and functional genomics studies in Ips pini yielded the discovery and characterization of the enzymes that convert mevalonate pathway intermediates to pheromone components, including a novel bifunctional geranyl diphosphate synthase/myrcene synthase, a cytochrome P450 that hydroxylates myrcene to ipsdienol, and an oxidoreductase that interconverts ipsdienol and ipsdienone to achieve the appropriate stereochemistry of ipsdienol for pheromonal activity. Furthermore, the regulation of these genes and their corresponding enzymes proved complex and diverse in different species. Mevalonate pathway genes in pheromone producing male I. pini

  2. Nowitna NWR 1986 waterfowl brood survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A waterfowl brood survey was conducted to continue monitoring trends in waterfowl production on the Nowitna National Wildlife Refuge. At least 13 duck species breed...

  3. US Forest Service Periodical Cicada Broods

    Data.gov (United States)

    US Forest Service, Department of Agriculture — A map service on the www depicting periodical cicada distribution and expected year of emergence by cicada brood and county. The periodical cicada emerges in massive...

  4. Experimental late brood surveys: Southern Saskatchewan: 1991

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the late brood surveys for southern Saskatchewan during 1991. Survey methods, weather and habitat conditions, production indices, and tables...

  5. Waterfowl brood data 2012-2013

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — 2012-2013 data from the 2.03 waterfowl production brood monitoring survey that monitors waterfowl production throughout the Fish Springs National Wildlife Refuge....

  6. Is androstadienone a putative human pheromone?

    Science.gov (United States)

    Marazziti, D; Torri, P; Baroni, S; Catena Dell'Osso, M; Consoli, G; Boncinelli, V

    2011-01-01

    On the basis of different evidences, androstadienone, a steroid compound produced in the armpit, has been proposed as a human pheromone, although its physiological levels appear too low to induce a response under experimental conditions. For this reason, the majority of researchers in this area puts into question the "legitimacy" of androstadienone, and prefers to consider the axillary extracts in its entirety, like a sort of "medicinal tea", the components of which still remain to be identified, but that taken together may induce a response, or function as a carrier of other active substances. Another option is that androstadienone acts with varying degrees of potency and, at lower concentrations, according to the context and to specific behavioral situations. The aim of this paper is to review all relevant data regarding androstadienone, in order to ascertain whether it may be considered a physiological pheromone and, as such, a possible target of future modulators of some human behaviors.

  7. The evolution of pheromonal communication.

    Science.gov (United States)

    Swaney, William T; Keverne, Eric B

    2009-06-25

    Small-brained rodents have been the principle focus for pheromonal research and have provided comprehensive insights into the chemosensory mechanisms that underpin pheromonal communication and the hugely important roles that pheromones play in behavioural regulation. However, pheromonal communication does not start or end with the mouse and the rat, and work in amphibians reveals much about the likely evolutionary origins of the chemosensory systems that mediate pheromonal effects. The dual olfactory organs (the main olfactory epithelium and the vomeronasal organ), their receptors and their separate projection pathways appear to have ancient evolutionary origins, appearing in the aquatic ancestors of all tetrapods during the Devonian period and so pre-dating the transition to land. While the vomeronasal organ has long been considered an exclusively pheromonal organ, accumulating evidence indicates that it is not the sole channel for the transduction of pheromonal information and that both olfactory systems have been co-opted for the detection of different pheromone signals over the course of evolution. This has also led to great diversity in the vomeronasal and olfactory receptor families, with enormous levels of gene diversity and inactivation of genes in different species. Finally, the evolution of trichromacy as well as huge increases in social complexity have minimised the role of pheromones in the lives of primates, leading to the total inactivation of the vomeronasal system in catarrhine primates while the brain increased in size and behaviour became emancipated from hormonal regulation.

  8. [ATPase and phosphatase activity of drone brood].

    Science.gov (United States)

    Bodnarchuk, L I; Stakhman, O S

    2004-01-01

    Most researches on insect enzymes concern carbohydrate and nitrogenous exchange. Data on ATPase activity for larval material of drone brood are absent in the available literature. The drone brood is one of the least investigated apiproducts. Allowing for the important role of ATPase in the vital functions of the insect cells our work was aimed at the study of ATPase of the drone blood activity and that of alkaline and acid phosphatases. When studying liophylised preparations of the drone brood homogenate we have found out high activity of Mg2+, Na+, K+-, Ca2+- and Mg2+-ATPase and of alkaline and acid phosphatase, that is the possible explanation of the high-intensity power and plastic processes proceeding during growth and development of larvae.

  9. Proteinaceous Pheromone Homologs Identified from the Cloacal Gland Transcriptome of a Male Axolotl, Ambystoma mexicanum.

    Directory of Open Access Journals (Sweden)

    Kevin W Hall

    Full Text Available Pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. Courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male Cynops pyrrhogaster. Other proteinaceous pheromones in salamanders have been shown to elicit responses from females towards conspecific males. The presence and levels of expression of proteinaceous pheromones have not been identified in the family Ambystomatidae, which includes several important research models. The objective of this research was therefore to identify putative proteinaceous pheromones from male axolotls, Ambystoma mexicanum, as well as their relative expression levels. The results indicate that axolotls possess two different forms of sodefrin precursor-like factor (alpha and beta, as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The results are from a single male axolotl; therefore, we are unable to assess how representative our results may be. Nevertheless, the presence of these highly expressed proteinaceous pheromones suggests that male axolotls use multiple chemical cues to attract female conspecifics. Behavioral assays would indicate whether the putative protein pheromones elicit courtship activity from female axolotls.

  10. Proteinaceous Pheromone Homologs Identified from the Cloacal Gland Transcriptome of a Male Axolotl, Ambystoma mexicanum.

    Science.gov (United States)

    Hall, Kevin W; Eisthen, Heather L; Williams, Barry L

    2016-01-01

    Pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. Courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male Cynops pyrrhogaster. Other proteinaceous pheromones in salamanders have been shown to elicit responses from females towards conspecific males. The presence and levels of expression of proteinaceous pheromones have not been identified in the family Ambystomatidae, which includes several important research models. The objective of this research was therefore to identify putative proteinaceous pheromones from male axolotls, Ambystoma mexicanum, as well as their relative expression levels. The results indicate that axolotls possess two different forms of sodefrin precursor-like factor (alpha and beta), as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The results are from a single male axolotl; therefore, we are unable to assess how representative our results may be. Nevertheless, the presence of these highly expressed proteinaceous pheromones suggests that male axolotls use multiple chemical cues to attract female conspecifics. Behavioral assays would indicate whether the putative protein pheromones elicit courtship activity from female axolotls.

  11. Pheromones in the fruit fly.

    Science.gov (United States)

    Chin, Jacqueline S R; Yew, Joanne Y

    2013-01-01

    The identification of pheromones (chemical communication cues) is critical to our understanding of complex social behavior in insects and other animals. In this chapter, we describe analytical methods for the purification of lipid pheromones by thin layer chromatography and the quantification and determination of their elemental composition by mass spectrometry.

  12. Standard methods for fungal brood disease research

    DEFF Research Database (Denmark)

    Jensen, Annette Bruun; Aronstein, Kathrine; Manuel Flores, Jose;

    2013-01-01

    Chalkbrood and stonebrood are two fungal diseases associated with honey bee brood. Chalkbrood, caused by Ascosphaera apis, is a common and widespread disease that can result in severe reduction of emerging worker bees and thus overall colony productivity. Stonebrood is caused by Aspergillus spp. ...

  13. Complex nature of enterococcal pheromone-responsive plasmids.

    Science.gov (United States)

    Wardal, Ewa; Sadowy, Ewa; Hryniewicz, Waleria

    2010-01-01

    Pheromone-responsive plasmids constitute a unique group of approximately 20 plasmids identified, as yet, only among enterococcal species. Several of their representatives, e.g. pAD1, pCF10, pPD1 and pAM373 have been extensively studied. These plasmids possess a sophisticated conjugation mechanism based on response to sex pheromones--small peptides produced by plasmid-free recipient cells. Detailed analysis of regulation and function of the pheromone response process revealed its great complexity and dual role--in plasmid conjugation and modulation of enterococcal virulence. Among other functional modules identified in pheromone plasmids, the stabilization/partition systems play a crucial role in stable maintenance of the plasmid molecule in host bacteria. Among them, the par locus of pAD1 is one of the exceptional RNA addiction systems. Pheromone-responsive plasmids contribute also to enterococcal phenotype being an important vehicle of antibiotic resistance in this genus. Both types of acquired vancomycin resistance determinants, vanA and vanB, as well many other resistant phenotypes, were found to be located on these plasmids. They also encode two basic agents of enterococcal virulence, i.e. aggregation substance (AS) and cytolysin. AS participates in mating-pair formation during conjugation but can also facilitate the adherence ofenterococci to human tissues during infection. The second protein, cytolysin, displays hemolytic activity and helps to invade eukaryotic cells. There are still many aspects of the nature of pheromone plasmids that remain unclear and more detailed studies are needed to understand their uniqueness and complexity.

  14. Brood size constrains the development of endothermy in blue tits.

    Science.gov (United States)

    Andreasson, Fredrik; Nord, Andreas; Nilsson, Jan-Åke

    2016-07-15

    Altricial birds are unable to maintain body temperature when exposed to low ambient temperatures during the first days after hatching. Thermoregulatory capacity begins to form as postnatal development progresses, and eventually nestlings become homeothermic. Several factors may influence this development at both the level of the individual and the level of the whole brood, but to our knowledge no studies have focused on the effect of brood size per se on the development of endothermy in individual nestlings. We performed cooling experiments on blue tit (Cyanistes caeruleus) nestlings in the field, to study how different experimental brood sizes affected the development of endothermy in individual nestlings and the thermal environment experienced by the whole brood in the nest. Nestlings from all experimental brood sizes showed a decrease in cooling rate as they grew older, but birds from reduced broods showed an earlier onset of endothermy compared with nestlings from enlarged and control broods. This difference manifested during early development and gradually disappeared as nestlings grew older. The thermal environment in the nests differed between treatments during nestling development, such that nest temperature in reduced broods was lower than that in enlarged broods during all days and during nights at the end of the experimental period. We suggest that the development of endothermy in blue tit nestlings is not ontogenetically fixed, but instead may vary according to differences in developmental, nutritional and thermal conditions as determined by brood size.

  15. Oviposition pheromones in haematophagous insects.

    Science.gov (United States)

    Seenivasagan, T; Vijayaraghavan, R

    2010-01-01

    Pheromones influencing oviposition behavior in females of haematophagous insects have been the interest of recent past by many group of scientists working on oviposition pheromones. Finding and choosing a good site for oviposition is a challenging task for females of haematophagous insects, especially in those insects which does not have the parental care. Their decisions have far-reaching and profound consequences for the life history of the offspring. In such blood feeding insects, the choice of oviposition site is affected by pheromones, which may function either as deterrents or stimulants in short range, while they may also act as repellents or attractants in long range perception. During the location of a suitable oviposition site for egg laying or a potential host for blood feeding, haematophagous insects mainly use olfactory and visual cues. These pheromones are produced by the ovipositing female or by conspecific larvae co-occurring with gravid females. Adult females detect oviposition pheromones by odor receptors on the antennae, as well as by contact chemoreceptors on tarsi, mouthparts and antennae. Different cues exploited by gravid females from a diversified arena include egg, larva, habitat, microbes, infusions and plant produced volatiles influence the oviposition behavior. Traps baited with pheromones, infusions, and insecticides shall be promising tools for monitoring and control of target insect using integrated vector management strategies.

  16. Chiral methyl-branched pheromones.

    Science.gov (United States)

    Ando, Tetsu; Yamakawa, Rei

    2015-07-01

    Insect pheromones are some of the most interesting natural products because they are utilized for interspecific communication between various insects, such as beetles, moths, ants, and cockroaches. A large number of compounds of many kinds have been identified as pheromone components, reflecting the diversity of insect species. While this review deals only with chiral methyl-branched pheromones, the chemical structures of more than one hundred non-terpene compounds have been determined by applying excellent analytical techniques. Furthermore, their stereoselective syntheses have been achieved by employing trustworthy chiral sources and ingenious enantioselective reactions. The information has been reviewed here not only to make them available for new research but also to understand the characteristic chemical structures of the chiral pheromones. Since biosynthetic studies are still limited, it might be meaningful to examine whether the structures, particularly the positions and configurations of the branched methyl groups, are correlated with the taxonomy of the pheromone producers and also with the function of the pheromones in communication systems.

  17. A Forward Genetic Screen for Molecules Involved in Pheromone-Induced Dauer Formation in Caenorhabditis elegans

    Science.gov (United States)

    Neal, Scott J.; Park, JiSoo; DiTirro, Danielle; Yoon, Jason; Shibuya, Mayumi; Choi, Woochan; Schroeder, Frank C.; Butcher, Rebecca A.; Kim, Kyuhyung; Sengupta, Piali

    2016-01-01

    Animals must constantly assess their surroundings and integrate sensory cues to make appropriate behavioral and developmental decisions. Pheromones produced by conspecific individuals provide critical information regarding environmental conditions. Ascaroside pheromone concentration and composition are instructive in the decision of Caenorhabditis elegans to either develop into a reproductive adult or enter into the stress-resistant alternate dauer developmental stage. Pheromones are sensed by a small set of sensory neurons, and integrated with additional environmental cues, to regulate neuroendocrine signaling and dauer formation. To identify molecules required for pheromone-induced dauer formation, we performed an unbiased forward genetic screen and identified phd (pheromone response-defective dauer) mutants. Here, we describe new roles in dauer formation for previously identified neuronal molecules such as the WD40 domain protein QUI-1 and MACO-1 Macoilin, report new roles for nociceptive neurons in modulating pheromone-induced dauer formation, and identify tau tubulin kinases as new genes involved in dauer formation. Thus, phd mutants define loci required for the detection, transmission, or integration of pheromone signals in the regulation of dauer formation. PMID:26976437

  18. A Forward Genetic Screen for Molecules Involved in Pheromone-Induced Dauer Formation in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Scott J. Neal

    2016-05-01

    Full Text Available Animals must constantly assess their surroundings and integrate sensory cues to make appropriate behavioral and developmental decisions. Pheromones produced by conspecific individuals provide critical information regarding environmental conditions. Ascaroside pheromone concentration and composition are instructive in the decision of Caenorhabditis elegans to either develop into a reproductive adult or enter into the stress-resistant alternate dauer developmental stage. Pheromones are sensed by a small set of sensory neurons, and integrated with additional environmental cues, to regulate neuroendocrine signaling and dauer formation. To identify molecules required for pheromone-induced dauer formation, we performed an unbiased forward genetic screen and identified phd (pheromone response-defective dauer mutants. Here, we describe new roles in dauer formation for previously identified neuronal molecules such as the WD40 domain protein QUI-1 and MACO-1 Macoilin, report new roles for nociceptive neurons in modulating pheromone-induced dauer formation, and identify tau tubulin kinases as new genes involved in dauer formation. Thus, phd mutants define loci required for the detection, transmission, or integration of pheromone signals in the regulation of dauer formation.

  19. A Forward Genetic Screen for Molecules Involved in Pheromone-Induced Dauer Formation in Caenorhabditis elegans.

    Science.gov (United States)

    Neal, Scott J; Park, JiSoo; DiTirro, Danielle; Yoon, Jason; Shibuya, Mayumi; Choi, Woochan; Schroeder, Frank C; Butcher, Rebecca A; Kim, Kyuhyung; Sengupta, Piali

    2016-05-03

    Animals must constantly assess their surroundings and integrate sensory cues to make appropriate behavioral and developmental decisions. Pheromones produced by conspecific individuals provide critical information regarding environmental conditions. Ascaroside pheromone concentration and composition are instructive in the decision of Caenorhabditis elegans to either develop into a reproductive adult or enter into the stress-resistant alternate dauer developmental stage. Pheromones are sensed by a small set of sensory neurons, and integrated with additional environmental cues, to regulate neuroendocrine signaling and dauer formation. To identify molecules required for pheromone-induced dauer formation, we performed an unbiased forward genetic screen and identified phd (pheromone response-defective dauer) mutants. Here, we describe new roles in dauer formation for previously identified neuronal molecules such as the WD40 domain protein QUI-1 and MACO-1 Macoilin, report new roles for nociceptive neurons in modulating pheromone-induced dauer formation, and identify tau tubulin kinases as new genes involved in dauer formation. Thus, phd mutants define loci required for the detection, transmission, or integration of pheromone signals in the regulation of dauer formation.

  20. Spider pheromones - a structural perspective.

    Science.gov (United States)

    Schulz, Stefan

    2013-01-01

    Spiders use pheromones for sexual communication, as do other animals such as insects. Nevertheless, knowledge about their chemical structure, function, and biosynthesis is only now being unraveled. Many studies have shown the existence of spider pheromones, but the responsible compounds have been elucidated in only a few cases. This review focuses on a structural approach because we need to know the involved chemistry if we are to understand fully the function of a pheromonal communication system. Pheromones from members of the spider families Pholcidae, Araneidae, Linyphiidae, Agenelidae, and Ctenidae are currently being identified and will be discussed in this review. Some of these compounds belong to compound classes not known from other arthropod pheromones, such as citric acid derivatives or acylated amino acids, whereas others originate from more common fatty acid metabolism. Their putative biosynthesis, their function, and the identification methods used will be discussed. Furthermore, other semiochemicals and the chemistry of apolar surface lipids that potentially might be used by spiders for communication are described briefly.

  1. Kisspeptin: a new neuronal target of primer pheromones in the control of reproductive function in mammals.

    Science.gov (United States)

    Jouhanneau, Mélanie; Szymanski, Laura; Martini, Mariangela; Ella, Arsène; Keller, Matthieu

    2013-07-01

    Pheromones are known to trigger either short-term behavioral responses, usually referred to as "releaser effects", or more long-term physiological changes, known as "primer effects", which especially affect reproductive function at the level of the gonadotrope axis. The precise mechanisms through which pheromones interact with the gonadotrope axis in the hypothalamus is not fully known. We propose that the neuropeptide Kisspeptin, could be a specific target of primer pheromones, allowing these pheromones to modulate the gonadotrope axis and GnRH activity. This emerging hypothesis is discussed in the context of puberty acceleration in female mice and the male effect in female ungulates (sheep or goat). These examples have been chosen to illustrate the diversity of the reproductive contexts in mammals and potential mechanisms affected by primer effects at the level of the gonadotrope axis.

  2. Are queen ants inhibited by their own pheromone?

    DEFF Research Database (Denmark)

    Holman, L.; Leroy, C.; Jørgensen, Charlotte

    2013-01-01

    . Communication in social insects is predominantly chemical, and the mechanisms regulating processes such as reproductive division of labor are becoming increasingly well understood. Recently, a queen cuticular hydrocarbon (3-MeC31) that inhibits worker reproduction and aggression was isolated in the ant Lasius...... reproductives. The data suggest that queen pheromones have a multifaceted role in colony organization, allowing queens and workers alike to modulate their behavior and physiology in response to changes in colony composition. © The Author 2012....

  3. How flies respond to honey bee pheromone: the role of the foraging gene on reproductive response to queen mandibular pheromone

    Science.gov (United States)

    Camiletti, Alison L.; Awde, David N.; Thompson, Graham J.

    2014-01-01

    In this study we test one central prediction from sociogenomic theory—that social and non-social taxa share common genetic toolkits that regulate reproduction in response to environmental cues. We exposed Drosophila females of rover ( for R) and sitter ( for s) genotypes to an ovary-suppressing pheromone derived from the honeybee Apis mellifera. Surprisingly, queen mandibular pheromone (QMP) affected several measures of fitness in flies, and in a manner comparable to the pheromone's normal effect on bee workers. QMP-treated sitter flies had smaller ovaries that contained fewer eggs than did untreated controls. QMP-treated rover flies, by contrast, showed a more variable pattern that only sometimes resulted in ovary inhibition, while a third strain of fly that contains a sitter mutant allele in a rover background ( for s2) showed no ovarian response to QMP. Taken together, our results suggest that distinctly non-social insects have some capacity to respond to social cues, but that this response varies with fly genotype. In general, the interspecific response is consistent with a conserved gene set affecting reproductive physiology. The differential response among strains in particular suggests that for is itself important for modulating the fly's pheromonal response.

  4. Does the removal of mite-infested brood facilitate grooming?

    Science.gov (United States)

    The relationship between the removal of mite-infested brood and mite drop was compared using Russian (RHB, n = 9) and Italian (IHB, n = 9) honey bee colonies. A cloake board was used to isolate test brood frame on the top hive body and the metal sheet served as a varroa trap. Inoculum mites were col...

  5. Human pheromones and sexual attraction.

    Science.gov (United States)

    Grammer, Karl; Fink, Bernhard; Neave, Nick

    2005-02-01

    Olfactory communication is very common amongst animals, and since the discovery of an accessory olfactory system in humans, possible human olfactory communication has gained considerable scientific interest. The importance of the human sense of smell has by far been underestimated in the past. Humans and other primates have been regarded as primarily 'optical animals' with highly developed powers of vision but a relatively undeveloped sense of smell. In recent years this assumption has undergone major revision. Several studies indicate that humans indeed seem to use olfactory communication and are even able to produce and perceive certain pheromones; recent studies have found that pheromones may play an important role in the behavioural and reproduction biology of humans. In this article we review the present evidence of the effect of human pheromones and discuss the role of olfactory cues in human sexual behaviour.

  6. Standard methods for fungal brood disease research

    DEFF Research Database (Denmark)

    Jensen, Annette Bruun; Aronstein, Kathrine; Manuel Flores, Jose;

    2013-01-01

    Chalkbrood and stonebrood are two fungal diseases associated with honey bee brood. Chalkbrood, caused by Ascosphaera apis, is a common and widespread disease that can result in severe reduction of emerging worker bees and thus overall colony productivity. Stonebrood is caused by Aspergillus spp. ...... interactions. We give guidelines on the preferred methods used in current research and the application of molecular techniques. We have added photographs, drawings and illustrations to assist bee-extension personnel and bee scientists in the control of these two diseases....... tissues upon inhalation by humans. In the current chapter we describe the honey bee disease symptoms of these fungal pathogens. In addition, we provide research methodologies and protocols for isolating and culturing, in vivo and in vitro assays that are commonly used to study these host pathogen...

  7. Vomeronasal organ and human pheromones.

    Science.gov (United States)

    Trotier, D

    2011-09-01

    For many organisms, pheromonal communication is of particular importance in managing various aspects of reproduction. In tetrapods, the vomeronasal (Jacobson's) organ specializes in detecting pheromones in biological substrates of congeners. This information triggers behavioral changes associated, in the case of certain pheromones, with neuroendocrine correlates. In human embryos, the organ develops and the nerve fibers constitute a substrate for the migration of GnRH-secreting cells from the olfactory placode toward the hypothalamus. After this essential step for subsequent secretion of sex hormones by the anterior hypophysis, the organ regresses and the neural connections disappear. The vomeronasal cavities can still be observed by endoscopy in some adults, but they lack sensory neurons and nerve fibers. The genes which code for vomeronasal receptor proteins and the specific ionic channels involved in the transduction process are mutated and nonfunctional in humans. In addition, no accessory olfactory bulbs, which receive information from the vomeronasal receptor cells, are found. The vomeronasal sensory function is thus nonoperational in humans. Nevertheless, several steroids are considered to be putative human pheromones; some activate the anterior hypothalamus, but the effects observed are not comparable to those in other mammals. The signaling process (by neuronal detection and transmission to the brain or by systemic effect) remains to be clearly elucidated.

  8. The evolution of female sex pheromones

    Directory of Open Access Journals (Sweden)

    Ally R. HARARI, Hadass STEINITZ

    2013-08-01

    Full Text Available The role of female sex pheromones in natural selection, particularly as a means for species recognition to avoid the generation of hybrid offspring with low fitness, has been widely explored and is generally accepted by scholars. However, the significance of sex pheromones in shaping mate choice (sexual selection and in competition over breeding resources (social selection has been largely ignored. The effect of sexual selection on sex pheromones as a sexually dimorphic signaling trait has been discounted because the amount of pheromone released by females is typically minute, while the role of sex pheromones in competition over breeding resources (other than mates has not yet been considered. As a result of natural selection, variation in sex pheromones among females is expected to be low, and males are not expected to choose their mates among pheromone-releasing conspecific females. Sexual selection, on the other hand, should drive the increase in pheromone variance among females, and males are expected to choose females based on this variation. Moreover, social selection resulting from more general social interactions, for example competition among females for breeding sites and food, should also promote variance among female sex pheromones. Here, we review the current evidence for each of the three selection processes acting on sex pheromones of female moths as an advertising trait. We suggest that the three selection types are not mutually exclusive but rather act together to promote different fitness components in diverse ecological situations [Current Zoology 59 (4: 569–578, 2013].

  9. Pheromones and exocrine glands in Isoptera.

    Science.gov (United States)

    Costa-Leonardo, Ana Maria; Haifig, Ives

    2010-01-01

    Termites are eusocial insects that have a peculiar and intriguing system of communication using pheromones. The termite pheromones are composed of a blend of chemical substances and they coordinate different social interactions or activities, including foraging, building, mating, defense, and nestmate recognition. Some of these sociochemicals are volatile, spreading in the air, and others are contact pheromones, which are transmitted by trophallaxis and grooming. Among the termite semiochemicals, the most known are alarm, trail, sex pheromones, and hydrocarbons responsible for the recognition of nestmates. The sources of the pheromones are exocrine glands located all over the termite body. The principal exocrine structures considered pheromone-producing glands in Isoptera are the frontal, mandibular, salivary or labial, sternal, and tergal glands. The frontal gland is the source of alarm pheromone and defensive chemicals, but the mandibular secretions have been little studied and their function is not well established in Isoptera. The secretion of salivary glands involves numerous chemical compounds, some of them without pheromonal function. The worker saliva contains a phagostimulating pheromone and probably a building pheromone, while the salivary reservoir of some soldiers contains defensive chemicals. The sternal gland is the only source of trail-following pheromone, whereas sex pheromones are secreted by two glandular sources, the sternal and tergal glands. To date, the termite semiochemicals have indicated that few molecules are involved in their chemical communication, that is, the same compound may be secreted by different glands, different castes and species, and for different functions, depending on the concentration. In addition to the pheromonal parsimony, recent studies also indicate the occurrence of a synergic effect among the compounds involved in the chemical communication of Isoptera.

  10. Hormones and pheromones in regulation of insect behavior

    Science.gov (United States)

    Both pheromones and hormones are well recognized regulators of insect biology. However, the interactions between hormones and pheromones in coordinating insect biology are less well understood. We have studied the interactions between juvenile hormone, its precursor methyl farnesoate, and pheromon...

  11. Evaporation rate of emulsion and oil-base emulsion pheromones

    Science.gov (United States)

    Knowledge of pheromone evaporation rate is critical to distribute pheromone containers effectively in the forest, orchard and field. There are several factors influencing the pheromone evaporation rate that include wind speed, container size and porosity, release area, temperature, humidity, pherom...

  12. Effects of sex pheromones and sexual maturation on locomotor activity in female sea lamprey (Petromyzon marinus)

    Science.gov (United States)

    Walaszczyk, Erin J.; Johnson, Nicholas S.; Steibel, Juan Pedro; Li, Weiming

    2013-01-01

    Synchronization of male and female locomotor rhythmicity can play a vital role in ensuring reproductive success. Several physiological and environmental factors alter these locomotor rhythms. As sea lamprey, Petromyzon marinus, progress through their life cycle, their locomotor activity rhythm changes multiple times. The goal of this study was to elucidate the activity patterns of adult female sea lamprey during the sexual maturation process and discern the interactions of these patterns with exposure to male pheromones. During these stages, preovulated and ovulated adult females are exposed to sex pheromone compounds, which are released by spermiated males and attract ovulated females to the nest for spawning. The locomotor behavior of adult females was monitored in a natural stream with a passive integrated tag responder system as they matured, and they were exposed to a sex pheromone treatment (spermiated male washings) or a control (prespermiated male washings). Results showed that, dependent on the hour of day, male sex pheromone compounds reduce total activity (p pheromones modulate a locomotor rhythm in a vertebrate, and they suggest that the interaction between maturity stage and sex pheromone exposure contributes to the differential locomotor rhythms found in adult female sea lamprey. This phenomenon may contribute to the reproductive synchrony of mature adults, thus increasing reproductive success in this species.

  13. An anti-steroidogenic inhibitory primer pheromone in male sea lamprey (Petromyzon marinus)

    Science.gov (United States)

    Chung-Davidson, Yu-Wen; Wang, Huiyong; Bryan, Mara B.; Wu, Hong; Johnson, Nicholas S.; Li, Weiming

    2013-01-01

    Reproductive functions can be modulated by both stimulatory and inhibitory primer pheromones released by conspecifics. Many stimulatory primer pheromones have been documented, but relatively few inhibitory primer pheromones have been reported in vertebrates. The sea lamprey male sex pheromone system presents an advantageous model to explore the stimulatory and inhibitory primer pheromone functions in vertebrates since several pheromone components have been identified. We hypothesized that a candidate sex pheromone component, 7α, 12α-dihydroxy-5α-cholan-3-one-24-oic acid (3 keto-allocholic acid or 3kACA), exerts priming effects through the hypothalamic-pituitary-gonadal (HPG) axis. To test this hypothesis, we measured the peptide concentrations and gene expressions of lamprey gonadotropin releasing hormones (lGnRH) and the HPG output in immature male sea lamprey exposed to waterborne 3kACA. Exposure to waterborne 3kACA altered neuronal activation markers such as jun and jun N-terminal kinase (JNK), and lGnRH mRNA levels in the brain. Waterborne 3kACA also increased lGnRH-III, but not lGnRH-I or -II, in the forebrain. In the plasma, 3kACA exposure decreased all three lGnRH peptide concentrations after 1 h exposure. After 2 h exposure, 3kACA increased lGnRHI and -III, but decreased lGnRH-II peptide concentrations in the plasma. Plasma lGnRH peptide concentrations showed differential phasic patterns. Group housing condition appeared to increase the averaged plasma lGnRH levels in male sea lamprey compared to isolated males. Interestingly, 15α-hydroxyprogesterone (15α-P) concentrations decreased after prolonged 3kACA exposure (at least 24 h). To our knowledge, this is the only known synthetic vertebrate pheromone component that inhibits steroidogenesis in males.

  14. An anti-steroidogenic inhibitory primer pheromone in male sea lamprey (Petromyzon marinus).

    Science.gov (United States)

    Chung-Davidson, Yu-Wen; Wang, Huiyong; Bryan, Mara B; Wu, Hong; Johnson, Nicholas S; Li, Weiming

    2013-08-01

    Reproductive functions can be modulated by both stimulatory and inhibitory primer pheromones released by conspecifics. Many stimulatory primer pheromones have been documented, but relatively few inhibitory primer pheromones have been reported in vertebrates. The sea lamprey male sex pheromone system presents an advantageous model to explore the stimulatory and inhibitory primer pheromone functions in vertebrates since several pheromone components have been identified. We hypothesized that a candidate sex pheromone component, 7α, 12α-dihydroxy-5α-cholan-3-one-24-oic acid (3 keto-allocholic acid or 3kACA), exerts priming effects through the hypothalamic-pituitary-gonadal (HPG) axis. To test this hypothesis, we measured the peptide concentrations and gene expressions of lamprey gonadotropin releasing hormones (lGnRH) and the HPG output in immature male sea lamprey exposed to waterborne 3kACA. Exposure to waterborne 3kACA altered neuronal activation markers such as jun and jun N-terminal kinase (JNK), and lGnRH mRNA levels in the brain. Waterborne 3kACA also increased lGnRH-III, but not lGnRH-I or -II, in the forebrain. In the plasma, 3kACA exposure decreased all three lGnRH peptide concentrations after 1h exposure. After 2h exposure, 3kACA increased lGnRH-I and -III, but decreased lGnRH-II peptide concentrations in the plasma. Plasma lGnRH peptide concentrations showed differential phasic patterns. Group housing condition appeared to increase the averaged plasma lGnRH levels in male sea lamprey compared to isolated males. Interestingly, 15α-hydroxyprogesterone (15α-P) concentrations decreased after prolonged 3kACA exposure (at least 24h). To our knowledge, this is the only known synthetic vertebrate pheromone component that inhibits steroidogenesis in males.

  15. A novel mechanism regulating a sexual signal: the testosterone-based inhibition of female sex pheromone expression in garter snakes.

    Science.gov (United States)

    Parker, M Rockwell; Mason, Robert T

    2014-08-01

    Vertebrates communicate their sex to conspecifics through the use of sexually dimorphic signals, such as ornaments, behaviors and scents. Furthermore, the physiological connection between hormones and secondary sexual signal expression is key to understanding their dimorphism, seasonality and evolution. The red-sided garter snake (Thamnophis sirtalis parietalis) is the only reptile for which a described pheromone currently exists, and because garter snakes rely completely on the sexual attractiveness pheromone for species identification and mate choice, they constitute a unique model species for exploring the relationship between pheromones and the endocrine system. We recently demonstrated that estrogen can activate female pheromone production in male garter snakes. The purpose of this study was to determine the mechanism(s) acting to prevent female pheromone production in males. We found that castrated males (GX) are courted by wild males in the field and produce appreciable amounts of female sex pheromone. Furthermore, pheromone production is inhibited in castrates given testosterone implants (GX+T), suggesting that pheromone production is actively inhibited by the presence of testosterone. Lastly, testosterone supplementation alone (T) increased the production of several saturated methyl ketones in the pheromone but not the unsaturated ketones; this may indicate that saturated ketones are testosterone-activated components of the garter snake's skin lipid milieu. Collectively, our research has shown that pheromone expression in snakes results from two processes: activation by the feminizing steroid estradiol and inhibition by testosterone. We suggest that basal birds and garter snakes share common pathways of activation that modulate crucial intraspecific signals that originate from skin.

  16. Sexual communication via peptide and protein pheromones.

    Science.gov (United States)

    Touhara, Kazushige

    2008-12-01

    Pheromones are specific substances utilized by various organisms for intraspecific communication about sex, strain, or species. Although pheromones in terrestrial animals tend to be volatile airborne chemicals, large non-volatile molecules such as peptides and proteins are also utilized for sociosexual communication. Peptide pheromones are recognized by specific receptors expressed in the vertebrate vomeronasal organ that comprises a unique chemosensory system. The information is sent to the hypothalamic area wherein the signal is further integrated, leading to various pheromonal outputs. In this review, current knowledge on the structure and function of peptide and protein pheromones in vertebrates as well as the mechanisms underlying receptor-mediated signal processing will be summarized. The present review will also discuss why, from chemical and ecological points of view, peptide pheromones evolved.

  17. Brood rearing ecology of king eiders on the north slope of Alaska

    Science.gov (United States)

    Phillips, Laura M.; Powell, Abby N.

    2009-01-01

    We examined King Eider (Somateria spectabilis) brood survival in the Kuparak oil field in northern Alaska in 2002 and 2003 by monitoring hens with broods using radiotelemetry. We observed complete brood loss in eight of 10 broods. Broods survived less than 2 weeks on average, and most mortality occurred within 10 days of hatch. Distance hens traveled overland did not affect brood survival. Apparent King Eider brood survival in our study area was lower than reported for eider species in other areas. We recommend future studies examine if higher densities of predators in oil fields reduces King Eider duckling survival.

  18. Pheromone produced by the myxobacterium Stigmatella aurantiaca.

    OpenAIRE

    Stephens, K.; Hegeman, G D; White, D

    1982-01-01

    An extracellular, diffusible signaling molecule (pheromone) was produced by Stigmatella aurantiaca during fruiting body formation. The pheromone decreased the aggregation period in both the light and the dark and substituted for light in stimulating the maturation of aggregates into fruiting bodies. The cells were more sensitive to lower concentrations of pheromone in the light than in the dark, possibly explaining the stimulation of aggregation and fruiting body formation by light. The phero...

  19. Biosynthesis of the Caenorhabditis elegans dauer pheromone

    OpenAIRE

    Butcher, Rebecca A.; Ragains, Justin R.; Li, Weiqing; RUVKUN, GARY; Clardy, Jon; Mak, Ho Yi

    2009-01-01

    To sense its population density and to trigger entry into the stress-resistant dauer larval stage, Caenorhabditis elegans uses the dauer pheromone, which consists of ascaroside derivatives with short, fatty acid-like side chains. Although the dauer pheromone has been studied for 25 years, its biosynthesis is completely uncharacterized. The daf-22 mutant is the only known mutant defective in dauer pheromone production. Here, we show that daf-22 encodes a homolog of human sterol carrier protein...

  20. The 3rd International Symposium on Avian Brood Parasitism

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    正Invited participants on the 3rd International Symposium on Avian Brood Parasitism, sponsored by Hainan Normal University (HNU), China, Norwegian University of Science and Technology (NTNU), Norway, the Research Council of Norway, and China Ornithological Society (COS).

  1. Standard methods for fungal brood disease research.

    Science.gov (United States)

    Jensen, Annette Bruun; Aronstein, Kathrine; Flores, José Manuel; Vojvodic, Svjetlana; Palacio, María Alejandra; Spivak, Marla

    2013-01-01

    Chalkbrood and stonebrood are two fungal diseases associated with honey bee brood. Chalkbrood, caused by Ascosphaera apis, is a common and widespread disease that can result in severe reduction of emerging worker bees and thus overall colony productivity. Stonebrood is caused by Aspergillus spp. that are rarely observed, so the impact on colony health is not very well understood. A major concern with the presence of Aspergillus in honey bees is the production of airborne conidia, which can lead to allergic bronchopulmonary aspergillosis, pulmonary aspergilloma, or even invasive aspergillosis in lung tissues upon inhalation by humans. In the current chapter we describe the honey bee disease symptoms of these fungal pathogens. In addition, we provide research methodologies and protocols for isolating and culturing, in vivo and in vitro assays that are commonly used to study these host pathogen interactions. We give guidelines on the preferred methods used in current research and the application of molecular techniques. We have added photographs, drawings and illustrations to assist bee-extension personnel and bee scientists in the control of these two diseases.

  2. Pheromone disruption of Argentine ant trail integrity

    Science.gov (United States)

    Suckling, D.M.; Peck, R.W.; Manning, L.M.; Stringer, L.D.; Cappadonna, J.; El-Sayed, A. M.

    2008-01-01

    Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. ?? 2008 Springer Science+Business Media, LLC.

  3. A study of the female produced sex pheromone of Tenebrio molitor (Coleoptera: Tenebrionidae)

    Science.gov (United States)

    Mangat, Jaswinder

    Mating behaviour in the yellow mealworm beetle, Tenebrio molitor , is mediated by several pheromones, including the female-produced 4-methylnonanol (4-MNol). Mating causes a decline in the titre of 4-MNol. The overall goal of this study was to determine the biochemical mechanism(s) responsible for this decline: i.e., whether the decline was due to an inhibition of pheromone biosynthesis and/or a stimulation of pheromone degradation; whether the decline was caused by the physical effect of mating or was due to the transfer of a factor from the male; and to conduct a preliminary investigation of the regulatory and signal transduction mechanisms involved in the regulation of 4-MNol production. In vitro radioassays for 4-MNol biosynthesis and degradation were developed and used to compare the levels of 4-MNol biosynthesis and degradation in virgin and mated females. Mating caused an inhibition of 4-MNol biosynthesis within 2 hours, but did not affect the rate of pheromone degradation. Decapitation of virgin females caused an inhibition of pheromone biosynthesis and did not prevent the inhibitory effect of mating. The inhibitory effect of mating was mimicked in females that were artificially inseminated with male reproductive tract homogenates (MRTH), but not in females similarly "inseminated" with water, saline, or air. Furthermore, 4-MNol biosynthesis could be inhibited in vitro by the addition of MRTH. These findings indicate that the male transferred one or more pheromonostatic factor(s) to the female during copulation that acted directly on the pheromone-producing tissue (the ovaries). In order to investigate the biochemical basis for the inhibition of pheromone biosynthesis after mating, the role of calcium was determined by modulating the level of calcium (using a calcium chelator, an ionophore, and calcium). However, due to the precipitation of calcium with the phosphate present in the buffer solution, we were unable to determine the role of calcium in the

  4. Differential interactions of sex pheromone and plant odour in the olfactory pathway of a male moth.

    Directory of Open Access Journals (Sweden)

    Nina Deisig

    Full Text Available Most animals rely on olfaction to find sexual partners, food or a habitat. The olfactory system faces the challenge of extracting meaningful information from a noisy odorous environment. In most moth species, males respond to sex pheromone emitted by females in an environment with abundant plant volatiles. Plant odours could either facilitate the localization of females (females calling on host plants, mask the female pheromone or they could be neutral without any effect on the pheromone. Here we studied how mixtures of a behaviourally-attractive floral odour, heptanal, and the sex pheromone are encoded at different levels of the olfactory pathway in males of the noctuid moth Agrotis ipsilon. In addition, we asked how interactions between the two odorants change as a function of the males' mating status. We investigated mixture detection in both the pheromone-specific and in the general odorant pathway. We used a recordings from individual sensilla to study responses of olfactory receptor neurons, b in vivo calcium imaging with a bath-applied dye to characterize the global input response in the primary olfactory centre, the antennal lobe and c intracellular recordings of antennal lobe output neurons, projection neurons, in virgin and newly-mated males. Our results show that heptanal reduces pheromone sensitivity at the peripheral and central olfactory level independently of the mating status. Contrarily, heptanal-responding olfactory receptor neurons are not influenced by pheromone in a mixture, although some post-mating modulation occurs at the input of the sexually isomorphic ordinary glomeruli, where general odours are processed within the antennal lobe. The results are discussed in the context of mate localization.

  5. Variation in courtship ultrasounds of three Ostrinia moths with different sex pheromones.

    Directory of Open Access Journals (Sweden)

    Takuma Takanashi

    Full Text Available Moths use ultrasounds as well as pheromones for sexual communication. In closely related moth species, variations in ultrasounds and pheromones are likely to profoundly affect mate recognition, reproductive isolation, and speciation. The European corn borer, Ostrinia nubilalis, and its Asian congeners, Ostrinia furnacalis and Ostrinia scapulalis, exhibit within-species and between-species variation in their pheromone communication. Recently, we reported ultrasound communication in O. furnacalis; however, variations in ultrasounds in the three congeners have not been addressed to date. Here we investigated features of ultrasound production and hearing in O. nubilalis and O. scapulalis, and compared them with those of O. furnacalis. As in O. furnacalis, males of O. nubilalis and O. scapulalis produced ultrasounds during courtship by rubbing specialized scales on the wings against scales on the thorax. The covering of these scales with nail polish muffled the sounds and significantly reduced mating success in O. nubilalis, showing the importance of ultrasound signaling in mating. The ultrasounds produced by O. nubilalis and O. scapulalis were similar, consisting of long trains of pairs of pulses with a main energy at 40 kHz, but distinctly different from the ultrasound produced by O. furnacalis, consisting of groups of pulses peaking at 50 kHz and with substantially more energy up to 80 kHz. Despite overall similarities, temporal features and patterns of amplitude modulation differed significantly among the geographic populations of O. nubilalis and O. scapulalis, which differed in pheromone type. In contrast, no significant difference in hearing was found among the three species with regard to the most sensitive frequencies and hearing threshold levels. The patterns of variations in the songs and pheromones well reflected those of the phylogenetic relationships, implying that ultrasound and pheromone communications have diverged concordantly. Our

  6. The evolution of female sex pheromones

    Institute of Scientific and Technical Information of China (English)

    Ally R.HARARI; Hadass STEINITZ

    2013-01-01

    The role of female sex pheromones in natural selection,particularly as a means for species recognition to avoid the generation of hybrid offspring with low fitness,has been widely explored and is generally accepted by scholars.However,the significance of sex pheromones in shaping mate choice (sexual selection) and in competition over breeding resources (social selection) has been largely ignored.The effect of sexual selection on sex pheromones as a sexually dimorphic signaling trait has been discounted because the amount of pheromone released by females is typically minute,while the role of sex pheromones in competition over breeding resources (other than mates) has not yet been considered.As a result of natural selection,variation in sex pheromones among females is expected to be low,and males are not expected to choose their mates among pheromone-releasing conspecific females.Sexual selection,on the other hand,should drive the increase in pheromone variance among females,and males are expected to choose females based on this variation.Moreover,social selection resulting from more general social interactions,for example competition among females for breeding sites and food,should also promote variance among female sex pheromones.Here,we review the current evidence for each of the three selection processes acting on sex pheromones of female moths as an advertising trait.We suggest that the three selection types are not mutually exclusive but rather act together to promote different fitness components in diverse ecological situations.

  7. Ant brood function as life preservers during floods.

    Directory of Open Access Journals (Sweden)

    Jessica Purcell

    Full Text Available Social organisms can surmount many ecological challenges by working collectively. An impressive example of such collective behavior occurs when ants physically link together into floating 'rafts' to escape from flooded habitat. However, raft formation may represent a social dilemma, with some positions posing greater individual risks than others. Here, we investigate the position and function of different colony members, and the costs and benefits of this functional geometry in rafts of the floodplain-dwelling ant Formica selysi. By causing groups of ants to raft in the laboratory, we observe that workers are distributed throughout the raft, queens are always in the center, and 100% of brood items are placed on the base. Through a series of experiments, we show that workers and brood are extremely resistant to submersion. Both workers and brood exhibit high survival rates after they have rafted, suggesting that occupying the base of the raft is not as costly as expected. The placement of all brood on the base of one cohesive raft confers several benefits: it preserves colony integrity, takes advantage of brood buoyancy, and increases the proportion of workers that immediately recover after rafting.

  8. Free flight odor tracking in Drosophila: Effect of wing chemosensors, sex and pheromonal gene regulation

    Science.gov (United States)

    Houot, Benjamin; Gigot, Vincent; Robichon, Alain; Ferveur, Jean-François

    2017-01-01

    The evolution of powered flight in insects had major consequences for global biodiversity and involved the acquisition of adaptive processes allowing individuals to disperse to new ecological niches. Flies use both vision and olfactory input from their antennae to guide their flight; chemosensors on fly wings have been described, but their function remains mysterious. We studied Drosophila flight in a wind tunnel. By genetically manipulating wing chemosensors, we show that these structures play an essential role in flight performance with a sex-specific effect. Pheromonal systems are also involved in Drosophila flight guidance: transgenic expression of the pheromone production and detection gene, desat1, produced low, rapid flight that was absent in control flies. Our study suggests that the sex-specific modulation of free-flight odor tracking depends on gene expression in various fly tissues including wings and pheromonal-related tissues. PMID:28067325

  9. Drosophila Food-Associated Pheromones: Effect of Experience, Genotype and Antibiotics on Larval Behavior.

    Science.gov (United States)

    Thibert, Julien; Farine, Jean-Pierre; Cortot, Jérôme; Ferveur, Jean-François

    2016-01-01

    Animals ubiquitously use chemical signals to communicate many aspects of their social life. These chemical signals often consist of environmental cues mixed with species-specific signals-pheromones-emitted by conspecifics. During their life, insects can use pheromones to aggregate, disperse, choose a mate, or find the most suitable food source on which to lay eggs. Before pupariation, larvae of several Drosophila species migrate to food sources depending on their composition and the presence of pheromones. Some pheromones derive from microbiota gut activity and these food-associated cues can enhance larval attraction or repulsion. To explore the mechanisms underlying the preference (attraction/repulsion) to these cues and clarify their effect, we manipulated factors potentially involved in larval response. In particular, we found that the (i) early exposure to conspecifics, (ii) genotype, and (iii) antibiotic treatment changed D. melanogaster larval behavior. Generally, larvae-tested either individually or in groups-strongly avoided food processed by other larvae. Compared to previous reports on larval attractive pheromones, our data suggest that such attractive effects are largely masked by food-associated compounds eliciting larval aversion. The antagonistic effect of attractive vs. aversive compounds could modulate larval choice of a pupariation site and impact the dispersion of individuals in nature.

  10. Identification and Characterization of Pheromone Receptors and Interplay between Receptors and Pheromone Binding Proteins in the Diamondback Moth, Plutella xyllostella

    OpenAIRE

    Sun, Mengjing; Liu, Yang; Walker, William B.; Liu, Chengcheng; Lin, Kejian; Gu, Shaohua; ZHANG Yongjun; Zhou, Jingjiang; Wang, Guirong

    2013-01-01

    Moths depend on olfactory cues such as sex pheromones to find and recognize mating partners. Pheromone receptors (PRs) and Pheromone binding proteins (PBPs) are thought to be associated with olfactory signal transduction of pheromonal compounds in peripheral olfactory reception. Here six candidate pheromone receptor genes in the diamondback moth, Plutella xyllostella were identified and cloned. All of the six candidate PR genes display male-biased expression, which is a typical characteristic...

  11. Nest and brood attentiveness in female black ducks

    Science.gov (United States)

    Ringelman, J.K.; Longcore, J.R.; Owen, R.B.

    1982-01-01

    Incubation rhythms and brood attentiveness of radio-marked Black Ducks (Anas rubripes) were studied in southcentral Maine during 1977-1980. Recess duration and frequency differed between three females nesting near wetlands (x = 82 min, 2.3 recesses/day) and two nesting at upland sites(x = 183 min, I. I recesses/day), but incubation constancy was similar for all birds (x = 86.7%). A fourth wetland-nesting female apparently responded to the absence of down and concealing cover at the nest site by taking shorter and fewer recesses (x= 34 min, 1.0 recesses/day) than did other wetland-nesters with typical nests. Wetland-nesters took longer recesses with increasing air temperature and following long incubation sessions. After their ducklings were two weeks old, two brood-rearing females began leaving their broods to forage on nearby wetlands. Duration of rearing recess (x = 56 min) and total recess time (x = 94 min/day) were less during this mid-rearing stage than during the latter part of rearing (x = 265 min, 488 min/day). The two hen-brood bonds terminated at 43 and 48 days. We suggest that small endogenous nutrient reserves and the low density of invertebrate foods, typical of Black Duck breeding habitat, were critical factors affecting the evolution of Black Duck incubation behavior. Bouts of inattention during brood rearing may have also evolved in relation to food requirements; by foraging on wetlands away from their broods, females avoid competing with offspring for common food resources.

  12. A Drosophila protein family implicated in pheromone perception is related to Tay-Sachs GM2-activator protein.

    Science.gov (United States)

    Starostina, Elena; Xu, Aiguo; Lin, Heping; Pikielny, Claudio W

    2009-01-02

    Low volatility, lipid-like cuticular hydrocarbon pheromones produced by Drosophila melanogaster females play an essential role in triggering and modulating mating behavior, but the chemosensory mechanisms involved remain poorly understood. Recently, we showed that the CheB42a protein, which is expressed in only 10 pheromone-sensing taste hairs on the front legs of males, modulates progression to late stages of male courtship behavior in response to female-specific cuticular hydrocarbons. Here we report that expression of all 12 genes in the CheB gene family is predominantly or exclusively gustatory-specific, and occurs in many different, often non-overlapping patterns. Only the Gr family of gustatory receptor genes displays a comparable variety of gustatory-specific expression patterns. Unlike Grs, however, expression of all but one CheB gene is sexually dimorphic. Like CheB42a, other CheBs may therefore function specifically in gustatory perception of pheromones. We also show that CheBs belong to the ML superfamily of lipid-binding proteins, and are most similar to human GM2-activator protein (GM2-AP). In particular, GM2-AP residues involved in ligand binding are conserved in CheBs but not in other ML proteins. Finally, CheB42a is specifically secreted into the inner lumen of pheromone-sensing taste hairs, where pheromones interact with membrane-bound receptors. We propose that CheB proteins interact directly with lipid-like Drosophila pheromones and modulate their detection by the gustatory signal transduction machinery. Furthermore, as loss of GM2-AP in Tay-Sachs disease prevents degradation of GM2 gangliosides and results in neurodegeneration, the function of CheBs in pheromone response may involve biochemical mechanisms critical for lipid metabolism in human neurons.

  13. Fungal mating pheromones: choreographing the dating game.

    Science.gov (United States)

    Jones, Stephen K; Bennett, Richard J

    2011-07-01

    Pheromones are ubiquitous from bacteria to mammals - a testament to their importance in regulating inter-cellular communication. In fungal species, they play a critical role in choreographing interactions between mating partners during the program of sexual reproduction. Here, we describe how fungal pheromones are synthesized, their interactions with G protein-coupled receptors, and the signals propagated by this interaction, using Saccharomyces cerevisiae as a reference point. Divergence from this model system is compared amongst the ascomycetes and basidiomycetes, which reveals the wealth of information that has been gleaned from studying pheromone-driven processes across a wide spectrum of the fungal kingdom.

  14. Optimization for manufacturing system based on Pheromone

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2011-06-01

    Full Text Available A new optimization approach, called pheromone, which comes from the collective behavior of ant colonies for food foraging is proposed to optimize task allocation. These ants spread pheromone information and make global information available locally; thus, an ant agent only needs to observe its local environment in order to account for nonlocal concerns in its decisions. This approach has the capacity for task allocation model to automatically find efficient routing paths for processing orders and to reduce communication overhead, which exists in contract net protocol, in shop floor control system. An example confirms that a pheromone-based optimization approach has an excellent allocation performance in shop floor.

  15. Chemical analysis of aquatic pheromones in fish.

    Science.gov (United States)

    Stewart, Michael; Baker, Cindy F; Sorensen, Peter W

    2013-01-01

    Pheromones are chemicals that pass between members of the same species that have inherent meaning. In the case of fish, pheromones are water-soluble and found in low concentrations. As such, sensitive and selective methods are needed to separate and analyze these pheromones from an environmental matrix that may contain many other chemicals. This chapter describes a generic method used to concentrate and identify these chemicals and two extremely sensitive and selective methods for analysis, namely, mass spectrometry and enzyme-linked immunosorbent assay.

  16. Pheromone Static Routing Strategy for Complex Networks

    CERN Document Server

    Ling, Xiang; Jiang, Rui; Hu, Mao-Bin

    2011-01-01

    In this paper, we adopt the concept of pheromone to generate a set of static paths that can reach the performance of global dynamic routing strategy [Phys. Rev. E 81, 016113(2010)]. In the test stage, pheromone is dropped to the nodes by packets forwarded by the global dynamic routing strategy. After that, static paths are generated according to the density of pheromone. The output paths can greatly improve traffic systems' overall capacity on different network structures, including scale-free networks, small-world networks and random graphs. Because the paths are static, the system needs much less computational resource than the global dynamic routing strategy.

  17. Male rats respond to their own alarm pheromone.

    Science.gov (United States)

    Inagaki, Hideaki; Kiyokawa, Yasushi; Takeuchi, Yukari; Mori, Yuji

    2012-01-01

    Pheromones are defined as substances released from an individual (donor) that influence a second individual (recipient) of the same species. However, it is unclear whether mammalian pheromones can affect the donor itself. To address this question, the effect of self-exposure to an alarm pheromone was examined. Exposure to the alarm pheromone resulted in an enhanced anxiety response, which was not different between recipients that perceived their own pheromone and those that perceived another individual's pheromone. The present results suggest that the alarm pheromone influences the emotional system of the recipient as well as induces similar anxiogenic effects on the donor rat that released the alarm pheromone. This is the first evidence demonstrating the effectiveness of mammalian pheromone self-exposure.

  18. Old maids have more appeal: effects of age and pheromone source on mate attraction in an orb-web spider.

    Science.gov (United States)

    Cory, Anna-Lena; Schneider, Jutta M

    2016-01-01

    Background. In many insects and spider species, females attract males with volatile sex pheromones, but we know surprisingly little about the costs and benefits of female pheromone emission. Here, we test the hypothesis that mate attraction by females is dynamic and strategic in the sense that investment in mate attraction is matched to the needs of the female. We use the orb-web spider Argiope bruennichi in which females risk the production of unfertilised egg clutches if they do not receive a copulation within a certain time-frame. Methods. We designed field experiments to compare mate attraction by recently matured (young) females with females close to oviposition (old). In addition, we experimentally separated the potential sources of pheromone transmission, namely the female body and the web silk. Results. In accordance with the hypothesis of strategic pheromone production, the probability of mate attraction and the number of males attracted differed between age classes. While the bodies and webs of young females were hardly found by males, the majority of old females attracted up to two males within two hours. Old females not only increased pheromone emission from their bodies but also from their webs. Capture webs alone spun by old females were significantly more efficient in attracting males than webs of younger females. Discussion. Our results suggest that females modulate their investment in signalling according to the risk of remaining unmated and that they thereby economize on the costs associated with pheromone production and emission.

  19. Old maids have more appeal: effects of age and pheromone source on mate attraction in an orb-web spider

    Directory of Open Access Journals (Sweden)

    Anna-Lena Cory

    2016-04-01

    Full Text Available Background. In many insects and spider species, females attract males with volatile sex pheromones, but we know surprisingly little about the costs and benefits of female pheromone emission. Here, we test the hypothesis that mate attraction by females is dynamic and strategic in the sense that investment in mate attraction is matched to the needs of the female. We use the orb-web spider Argiope bruennichi in which females risk the production of unfertilised egg clutches if they do not receive a copulation within a certain time-frame. Methods. We designed field experiments to compare mate attraction by recently matured (young females with females close to oviposition (old. In addition, we experimentally separated the potential sources of pheromone transmission, namely the female body and the web silk. Results. In accordance with the hypothesis of strategic pheromone production, the probability of mate attraction and the number of males attracted differed between age classes. While the bodies and webs of young females were hardly found by males, the majority of old females attracted up to two males within two hours. Old females not only increased pheromone emission from their bodies but also from their webs. Capture webs alone spun by old females were significantly more efficient in attracting males than webs of younger females. Discussion. Our results suggest that females modulate their investment in signalling according to the risk of remaining unmated and that they thereby economize on the costs associated with pheromone production and emission.

  20. Olfactory attraction of the hornet Vespa velutina to honeybee colony odors and pheromones.

    Directory of Open Access Journals (Sweden)

    Antoine Couto

    Full Text Available Since the beginning of the last century, the number of biological invasions has continuously increased worldwide. Due to their environmental and economical consequences, invasive species are now a major concern. Social wasps are particularly efficient invaders because of their distinctive biology and behavior. Among them, the yellow-legged hornet, Vespa velutina, is a keen hunter of domestic honeybees. Its recent introduction to Europe may induce important beekeeping, pollination, and biodiversity problems. Hornets use olfactory cues for the long-range detection of food sources, in this case the location of honeybee colonies, but the exact nature of these cues remains unknown. Here, we studied the orientation behavior of V. velutina workers towards a range of hive products and protein sources, as well as towards prominent chemical substances emitted by these food sources. In a multiple choice test performed under controlled laboratory conditions, we found that hornets are strongly attracted to the odor of some hive products, especially pollen and honey. When testing specific compounds, the honeybee aggregation pheromone, geraniol, proved highly attractive. Pheromones produced by honeybee larvae or by the queen were also of interest to hornet workers, albeit to a lesser extent. Our results indicate that V. velutina workers are selectively attracted towards olfactory cues from hives (stored food, brood, and queen, which may signal a high prey density. This study opens new perspectives for understanding hornets' hunting behavior and paves the way for developing efficient trapping strategies against this invasive species.

  1. Olfactory attraction of the hornet Vespa velutina to honeybee colony odors and pheromones.

    Science.gov (United States)

    Couto, Antoine; Monceau, Karine; Bonnard, Olivier; Thiéry, Denis; Sandoz, Jean-Christophe

    2014-01-01

    Since the beginning of the last century, the number of biological invasions has continuously increased worldwide. Due to their environmental and economical consequences, invasive species are now a major concern. Social wasps are particularly efficient invaders because of their distinctive biology and behavior. Among them, the yellow-legged hornet, Vespa velutina, is a keen hunter of domestic honeybees. Its recent introduction to Europe may induce important beekeeping, pollination, and biodiversity problems. Hornets use olfactory cues for the long-range detection of food sources, in this case the location of honeybee colonies, but the exact nature of these cues remains unknown. Here, we studied the orientation behavior of V. velutina workers towards a range of hive products and protein sources, as well as towards prominent chemical substances emitted by these food sources. In a multiple choice test performed under controlled laboratory conditions, we found that hornets are strongly attracted to the odor of some hive products, especially pollen and honey. When testing specific compounds, the honeybee aggregation pheromone, geraniol, proved highly attractive. Pheromones produced by honeybee larvae or by the queen were also of interest to hornet workers, albeit to a lesser extent. Our results indicate that V. velutina workers are selectively attracted towards olfactory cues from hives (stored food, brood, and queen), which may signal a high prey density. This study opens new perspectives for understanding hornets' hunting behavior and paves the way for developing efficient trapping strategies against this invasive species.

  2. The benefit of large broods in barnacle geese : a study using natural and experimental manipulations

    NARCIS (Netherlands)

    Loonen, MJJE; Bruinzeel, LW; Black, JM; Drent, RH

    1999-01-01

    1. In precocial birds, where the young feed themselves, the costs and benefits of brood size are still poorly understood. An experimental manipulation of brood size was employed to examine the effects of brood size on both parents and young in a wild population of barnacle geese [Branta leucopsis (B

  3. Diurnal brooding behavior of long-tailed tits (Aegithalos caudatus glaucogularis).

    Science.gov (United States)

    Yu, Jin; Wang, Peng-Cheng; Lü, Lei; Zhang, Zheng-Wang; Wang, Yong; Xu, Ji-Liang; Li, Jian-Qiang; Xi, Bo; Zhu, Jia-Gui; Du, Zhi-Yong

    2016-03-18

    Brooding is a major breeding investment of parental birds during the early nestling stage, and has important effects on the development and survival of nestlings. Investigating brooding behavior can help to understand avian breeding investment strategies. From January to June in 2013 and 2014, we studied the brooding behaviors of long-tailed tits (Aegithalos caudatus glaucogularis) in Dongzhai National Nature Reserve, Henan Province, China. We analyzed the relationships between parental diurnal brooding duration and nestling age, brood size, temperature, relative breeding season, time of day and nestling frequencies during brooding duration. Results showed that female and male long-tailed tit parents had different breeding investment strategies during the early nestling stage. Female parents bore most of the brooding investment, while male parents performed most of the nestling feedings. In addition, helpers were not found to brood nestlings at the two cooperative breeding nests. Parental brooding duration was significantly associated with the food delivered to nestlings (F=86.10, df=1, 193.94, Ptit nestlings might be able to maintain their own body temperature by this age. In addition, brooding duration was affected by both brood size (F=12.74, df=1, 32.08, P=0.001) and temperature (F=5.83, df=1, 39.59, P=0.021), with it being shorter in larger broods and when ambient temperature was higher.

  4. Standard methods for Apis mellifera brood as human food

    DEFF Research Database (Denmark)

    Jensen, Annette Bruun; Evans, Joshua David; Jonas-Levi, Adi

    2017-01-01

    methods and techniques from related fields of research. In this paper, we provide recommendations and research protocols centered on production of worker and drone brood for human consumption, on brood harvesting, including hygienic considerations, on nutritional aspects of brood, on sensory analyses...

  5. Do perfume additives termed human pheromones warrant being termed pheromones?

    Science.gov (United States)

    Winman, Anders

    2004-09-30

    Two studies of the effects of perfume additives, termed human pheromones by the authors, have conveyed the message that these substances can promote an increase in human sociosexual behaviour [Physiol. Behav. 75 (2003) R1; Arch. Sex. Behav. 27 (1998) R2]. The present paper presents an extended analysis of this data. It is shown that in neither study is there a statistically significant increase in any of the sociosexual behaviours for the experimental groups. In the control groups of both studies, there are, however, moderate but statistically significant decreases in the corresponding behaviour. Most notably, there is no support in data for the claim that the substances increase the attractiveness of the wearers of the substances to the other sex. It is concluded that more research using matched homogenous groups of participants is needed.

  6. Trans-Atlantic rafting by the brooding reef coral

    NARCIS (Netherlands)

    Hoeksema, B.W.; Roos, P.J.; Cadée, G.C.

    2012-01-01

    Specimens of the brooding reef coral Favia fragum were found on man-made flotsam stranded on the North Sea shore of the Netherlands. Based on the associated epifauna originating from the southeast USA, we estimate that the corals must have crossed the Atlantic Ocean, transported by the Gulf Stream a

  7. Brood size and immunity costs in zebra finches Taeniopygia guttata

    NARCIS (Netherlands)

    Verhulst, S; Riedstra, B; Wiersma, P

    2005-01-01

    Birds rearing experimentally enlarged broods have lower antibody responses to a novel antigen, and we tested three hypotheses that could explain this result. We used zebra finches Taeniopygia guttata inoculated with sheep red blood cells (SRBC) as a study system, for which this trade-off was previou

  8. Transcriptome of the Antarctic brooding gastropod mollusc Margarella antarctica.

    Science.gov (United States)

    Clark, Melody S; Thorne, Michael A S

    2015-12-01

    454 RNA-Seq transcriptome data were generated from foot tissue of the Antarctic brooding gastropod mollusc Margarella antarctica. A total of 6195 contigs were assembled de novo, providing a useful resource for researchers with an interest in Antarctic marine species, phylogenetics and mollusc biology, especially shell production.

  9. Invasion of Varroa mites into honey bee brood cells.

    NARCIS (Netherlands)

    Boot, W.J.

    1995-01-01

    The parasitic mite Varroa-jacobsoni is one of the most serious pests of Western honey bees, Apis mellifera. The mites parasitize adult bees, but reproduction only occurs while parasitizing on honey bee brood. Invasion into a drone or a worker cell is therefore a crucial step in the life of Varroa m

  10. Pheromone Static Routing Strategy for Complex Networks

    Science.gov (United States)

    Hu, Mao-Bin; Henry, Y. K. Lau; Ling, Xiang; Jiang, Rui

    2012-12-01

    We adopt the concept of using pheromones to generate a set of static paths that can reach the performance of global dynamic routing strategy [Phys. Rev. E 81 (2010) 016113]. The path generation method consists of two stages. In the first stage, a pheromone is dropped to the nodes by packets forwarded according to the global dynamic routing strategy. In the second stage, pheromone static paths are generated according to the pheromone density. The output paths can greatly improve traffic systems' overall capacity on different network structures, including scale-free networks, small-world networks and random graphs. Because the paths are static, the system needs much less computational resources than the global dynamic routing strategy.

  11. Fungal Mating Pheromones: Choreographing the Dating Game

    OpenAIRE

    2011-01-01

    Pheromones are ubiquitous from bacteria to mammals - a testament to their importance in regulating inter-cellular communication. In fungal species, they play a critical role in choreographing interactions between mating partners during the program of sexual reproduction. Here, we describe how fungal pheromones are synthesized, their interactions with G protein-coupled receptors, and the signals propagated by this interaction, using Saccharomyces cerevisiae as a reference point. Divergence fro...

  12. Behavioral analysis of pheromones in fish.

    Science.gov (United States)

    Sorensen, Peter W

    2013-01-01

    Pheromones are chemicals that pass between members of the same species which have inherent meaning. Because most fish pheromones are mixtures, and their actions can be complex, behavioral assays are required to identify them. This chapter describes a few strategies and two specific methods (one for measuring attraction and another for sexual arousal) that can serve this purpose in fishes that live in nonflowing water such as the carps.

  13. Moth sex pheromone receptors and deceitful parapheromones.

    Directory of Open Access Journals (Sweden)

    Pingxi Xu

    Full Text Available The insect's olfactory system is so selective that male moths, for example, can discriminate female-produced sex pheromones from compounds with minimal structural modifications. Yet, there is an exception for this "lock-and-key" tight selectivity. Formate analogs can be used as replacement for less chemically stable, long-chain aldehyde pheromones, because male moths respond physiologically and behaviorally to these parapheromones. However, it remained hitherto unknown how formate analogs interact with aldehyde-sensitive odorant receptors (ORs. Neuronal responses to semiochemicals were investigated with single sensillum recordings. Odorant receptors (ORs were cloned using degenerate primers, and tested with the Xenopus oocyte expression system. Quality, relative quantity, and purity of samples were evaluated by gas chromatography and gas chromatography-mass spectrometry. We identified olfactory receptor neurons (ORNs housed in trichoid sensilla on the antennae of male navel orangeworm that responded equally to the main constituent of the sex pheromone, (11Z,13Z-hexadecadienal (Z11Z13-16Ald, and its formate analog, (9Z,11Z-tetradecen-1-yl formate (Z9Z11-14OFor. We cloned an odorant receptor co-receptor (Orco and aldehyde-sensitive ORs from the navel orangeworm, one of which (AtraOR1 was expressed specifically in male antennae. AtraOR1•AtraOrco-expressing oocytes responded mainly to Z11Z13-16Ald, with moderate sensitivity to another component of the sex pheromone, (11Z,13Z-hexadecadien-1-ol. Surprisingly, this receptor was more sensitive to the related formate than to the natural sex pheromone. A pheromone receptor from Heliothis virescens, HR13 ( = HvirOR13 showed a similar profile, with stronger responses elicited by a formate analog than to the natural sex pheromone, (11Z-hexadecenal thus suggesting this might be a common feature of moth pheromone receptors.

  14. Increased brood size leads to persistent eroded telomeres

    Directory of Open Access Journals (Sweden)

    Sophie eReichert

    2014-04-01

    Full Text Available Costs of reproduction can be divided in mandatory costs coming from physiological, metabolic and anatomical changes required to sustain reproduction itself, and in investment-dependent costs that are likely to become apparent when reproductive efforts are exceeding what organisms were prepared to sustain. Interestingly, recent data showed that entering reproduction enhanced breeders’ telomere loss, but no data explored so far the impact of reproductive investment. Telomeres protect the ends of eukaryote chromosomes. Shortened telomeres were associated with shorter lifespan, telomere erosion being then proposed to powerfully quantify life’s insults. Here, we experimentally manipulated brood size in order to modify reproductive investment of adult zebra finches (Taeniopygia guttata below or beyond their (optimal starting investment and tested the consequences of our treatment on parents’ telomere dynamics. We show that an increased brood size led to a reduction in telomere lengths in both parents compared to control and to parents raising a reduced brood. This greater telomere erosion was detected in parents immediately after the reproductive event and the telomere length difference persisted up to one year later. However, we did not detect any effects of brood size manipulation on annual survival of parents kept under laboratory conditions. In addition, telomere lengths at the end of reproduction were not associated with annual survival. Altogether, although our findings highlight that fast telomere erosion can come as a cost of brood size manipulation, they provide mixed correlative support to the emerging hypothesis that telomere erosion could account for the links between high reproductive investment and longevity.

  15. Biosynthesis of the Caenorhabditis elegans dauer pheromone.

    Science.gov (United States)

    Butcher, Rebecca A; Ragains, Justin R; Li, Weiqing; Ruvkun, Gary; Clardy, Jon; Mak, Ho Yi

    2009-02-10

    To sense its population density and to trigger entry into the stress-resistant dauer larval stage, Caenorhabditis elegans uses the dauer pheromone, which consists of ascaroside derivatives with short, fatty acid-like side chains. Although the dauer pheromone has been studied for 25 years, its biosynthesis is completely uncharacterized. The daf-22 mutant is the only known mutant defective in dauer pheromone production. Here, we show that daf-22 encodes a homolog of human sterol carrier protein SCPx, which catalyzes the final step in peroxisomal fatty acid beta-oxidation. We also show that dhs-28, which encodes a homolog of the human d-bifunctional protein that acts just upstream of SCPx, is also required for pheromone production. Long-term daf-22 and dhs-28 cultures develop dauer-inducing activity by accumulating less active, long-chain fatty acid ascaroside derivatives. Thus, daf-22 and dhs-28 are required for the biosynthesis of the short-chain fatty acid-derived side chains of the dauer pheromone and link dauer pheromone production to metabolic state.

  16. Aggregation Pheromone System: A Real-parameter Optimization Algorithm using Aggregation Pheromones as the Base Metaphor

    Science.gov (United States)

    Tsutsui, Shigeyosi

    This paper proposes an aggregation pheromone system (APS) for solving real-parameter optimization problems using the collective behavior of individuals which communicate using aggregation pheromones. APS was tested on several test functions used in evolutionary computation. The results showed APS could solve real-parameter optimization problems fairly well. The sensitivity analysis of control parameters of APS is also studied.

  17. Alpha-acaridial a female sex pheromone from an alarm pheromone emilting mite Rhizoglyphus robini.

    Science.gov (United States)

    Mizoguchi, Atsuko; Mori, Naoki; Nishida, Ritsuo; Kuwahara, Yasumasa

    2003-07-01

    The female sex pheromone of Rhizoglyphus robini Claparède (Astigmata: Acaridae) was identified as alpha-acaridial [2(E)-(4-methyl-3-pentenyl)-butenedial], which stimulated males sexually and enhanced the frequency of male mounting behavior. Although a hexane extract of females manifested alarm pheromone activity against tested males due to the presence of the alarm pheromone neryl formate, silica gel column fractions containing alpha-acaridial evoked increased mounting behavior by males at a dose of 0.1 female equivalent. Synthetic alpha-acaridial at a dose of 10 ng showed a peak of activity as a sex pheromone, with a convex dose-response relationship. Its content was determined to be 388 +/- 244 ng per female and 163 +/- 97 ng per male by GC. This is the first time that two pheromones (the alarm pheromone neryl formate, and the sex pheromone alpha-acaridial) have been demonstrated to be components of the same opisthonotal gland secretion in astigmatid mites. A mechanism for the appropriate expression of the two pheromones by the mites under different conditions is proposed.

  18. Male axillary extracts contain pheromones that affect pulsatile secretion of luteinizing hormone and mood in women recipients.

    Science.gov (United States)

    Preti, George; Wysocki, Charles J; Barnhart, Kurt T; Sondheimer, Steven J; Leyden, James J

    2003-06-01

    Human underarm secretions, when applied to women recipients, alter the length and timing of the menstrual cycle. These effects are thought to arise from exposure to primer pheromones that are produced in the underarm. Pheromones can affect endocrine (primer) or behavioral (releaser) responses, provide information (signaler), or perhaps even modify emotion or mood (modulator). In this study, we extracted underarm secretions from pads worn by men and placed the extract under the nose of women volunteers while monitoring serum LH and emotion/mood. Pulses of LH are excellent indicators of the release of GnRH from the brain's hypothalamus. In women, the positive influence of GnRH on LH affects the length and timing of the menstrual cycle, which, in turn, affects fertility. Here we show that extracts of male axillary secretions have a direct effect upon LH-pulsing and mood of women. In our subjects, the putative male pheromone(s) advanced the onset of the next peak of LH after its application, reduced tension, and increased relaxation. These results demonstrate that male axillary secretions contain one or more constituents that act as primer and modulator pheromones.

  19. Chemistry of the pheromones of mealybug and scale insects.

    Science.gov (United States)

    Zou, Yunfan; Millar, Jocelyn G

    2015-07-01

    This article comprehensively reviews the syntheses of all known sex pheromones of scales and mealybugs, describes how they were identified, and how the synthetic pheromones are used in insect management.

  20. Evolved differences in larval social behavior mediated by novel pheromones.

    Science.gov (United States)

    Mast, Joshua D; De Moraes, Consuelo M; Alborn, Hans T; Lavis, Luke D; Stern, David L

    2014-12-12

    Pheromones, chemical signals that convey social information, mediate many insect social behaviors, including navigation and aggregation. Several studies have suggested that behavior during the immature larval stages of Drosophila development is influenced by pheromones, but none of these compounds or the pheromone-receptor neurons that sense them have been identified. Here we report a larval pheromone-signaling pathway. We found that larvae produce two novel long-chain fatty acids that are attractive to other larvae. We identified a single larval chemosensory neuron that detects these molecules. Two members of the pickpocket family of DEG/ENaC channel subunits (ppk23 and ppk29) are required to respond to these pheromones. This pheromone system is evolving quickly, since the larval exudates of D. simulans, the sister species of D. melanogaster, are not attractive to other larvae. Our results define a new pheromone signaling system in Drosophila that shares characteristics with pheromone systems in a wide diversity of insects.

  1. Pheromones and ovarian growth in African catfish Clarias gariepinus.

    NARCIS (Netherlands)

    Weerd, van J.H.

    1990-01-01

    Pheromones are defined as 'substances which are secreted to the outside by an individual and received by a second individual of the same species, in which they release a specific reaction'. In teleost fish, pheromones play a role in a variety of social interactions. Sex pheromones are involved in re

  2. Pheromone communication in the fission yeast Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Nielsen, O; Davey, William John; Nielsen, Olaf

    1995-01-01

    Conjugation between two haploid yeast cells is generally controlled by the reciprocal action of diffusible mating pheromones, cells of each mating type releasing pheromones that induce mating-specific changes in cells of the opposite type. Recent studies into pheromone signalling in the fission y...

  3. Male pheromone protein components activate female vomeronasal neurons in the salamander Plethodon shermani

    Directory of Open Access Journals (Sweden)

    Feldhoff Pamela W

    2006-03-01

    Full Text Available Abstract Background The mental gland pheromone of male Plethodon salamanders contains two main protein components: a 22 kDa protein named Plethodon Receptivity Factor (PRF and a 7 kDa protein named Plethodon Modulating Factor (PMF, respectively. Each protein component individually has opposing effects on female courtship behavior, with PRF shortening and PMF lengthening courtship. In this study, we test the hypothesis that PRF or PMF individually activate vomeronasal neurons. The agmatine-uptake technique was used to visualize chemosensory neurons that were activated by each protein component individually. Results Vomeronasal neurons exposed to agmatine in saline did not demonstrate significant labeling. However, a population of vomeronasal neurons was labeled following exposure to either PRF or PMF. When expressed as a percent of control level labeled cells, PRF labeled more neurons than did PMF. These percentages for PRF and PMF, added together, parallel the percentage of labeled vomeronasal neurons when females are exposed to the whole pheromone. Conclusion This study suggests that two specific populations of female vomeronasal neurons are responsible for responding to each of the two components of the male pheromone mixture. These two neural populations, therefore, could express different receptors which, in turn, transmit different information to the brain, thus accounting for the different female behavior elicited by each pheromone component.

  4. Virulence of mixed fungal infections in honey bee brood

    Directory of Open Access Journals (Sweden)

    Vojvodic Svjetlana

    2012-03-01

    Full Text Available Abstract Introduction Honey bees, Apis mellifera, have a diverse community of pathogens. Previous research has mostly focused on bacterial brood diseases of high virulence, but milder diseases caused by fungal pathogens have recently attracted more attention. This interest has been triggered by partial evidence that co-infection with multiple pathogens has the potential to accelerate honey bee mortality. In the present study we tested whether co-infection with closely related fungal brood-pathogen species that are either specialists or non-specialist results in higher host mortality than infections with a single specialist. We used a specially designed laboratory assay to expose honey bee larvae to controlled infections with spores of three Ascosphaera species: A. apis, the specialist pathogen that causes chalkbrood disease in honey bees, A. proliperda, a specialist pathogen that causes chalkbrood disease in solitary bees, and A. atra, a saprophytic fungus growing typically on pollen brood-provision masses of solitary bees. Results We show for the first time that single infection with a pollen fungus A. atra may induce some mortality and that co-infection with A. atra and A. apis resulted in higher mortality of honey bees compared to single infections with A. apis. However, similar single and mixed infections with A. proliperda did not increase brood mortality. Conclusion Our results show that co-infection with a closely related fungal species can either increase or have no effect on host mortality, depending on the identity of the second species. Together with other studies suggesting that multiple interacting pathogens may be contributing to worldwide honey bee health declines, our results highlight the importance of studying effects of multiple infections, even when all interacting species are not known to be specialist pathogens.

  5. Pheromones in the life of insects.

    Science.gov (United States)

    Lamprecht, Ingolf; Schmolz, Erik; Schricker, Burkhard

    2008-09-01

    Life in insect societies asks for a permanent flow of information, often carried by rather simple organic molecules. Some originate from plants as odours of blossoms or exudates from trees. Especially important are the intra- and interspecific combinations of compounds produced by the insects themselves. These are called pheromones or ecto-hormones and serve a variety of tasks. The paper deals mainly with honeybee pheromones, but takes also into consideration those of wasps and hornets. Effects of pheromones are monitored ethologically by direct observation and filming as well as in a more quantitative manner with using direct and indirect calorimetry. In all experimental set-ups alarm pheromones were used as controls. They show an up to fourfold increase of activity after a few seconds, determined for small groups of insects as well as for a whole hornet nest placed in a 25-l calorimeter. A variety of cosmetics like soaps, shampoos, lotions and perfumes are included in the investigations because of repeated reports about unwarranted insect attacks which are said to be provoked by such products. None of the applied substances provoked a significant reaction of the bees (p > 0.05). A short appendix discusses the still questionable existence of pheromones in man, which were confirmed under laboratory conditions, but not yet for daily life.

  6. Peptide pheromone signaling in Streptococcus and Enterococcus.

    Science.gov (United States)

    Cook, Laura C; Federle, Michael J

    2014-05-01

    Intercellular chemical signaling in bacteria, commonly referred to as quorum sensing (QS), relies on the production and detection of compounds known as pheromones to elicit coordinated responses among members of a community. Pheromones produced by Gram-positive bacteria are comprised of small peptides. Based on both peptide structure and sensory system architectures, Gram-positive bacterial signaling pathways may be classified into one of four groups with a defining hallmark: cyclical peptides of the Agr type, peptides that contain Gly-Gly processing motifs, sensory systems of the RNPP family, or the recently characterized Rgg-like regulatory family. The recent discovery that Rgg family members respond to peptide pheromones increases substantially the number of species in which QS is likely a key regulatory component. These pathways control a variety of fundamental behaviors including conjugation, natural competence for transformation, biofilm development, and virulence factor regulation. Overlapping QS pathways found in multiple species and pathways that utilize conserved peptide pheromones provide opportunities for interspecies communication. Here we review pheromone signaling identified in the genera Enterococcus and Streptococcus, providing examples of all four types of pathways.

  7. Honeybee Colony Vibrational Measurements to Highlight the Brood Cycle.

    Directory of Open Access Journals (Sweden)

    Martin Bencsik

    Full Text Available Insect pollination is of great importance to crop production worldwide and honey bees are amongst its chief facilitators. Because of the decline of managed colonies, the use of sensor technology is growing in popularity and it is of interest to develop new methods which can more accurately and less invasively assess honey bee colony status. Our approach is to use accelerometers to measure vibrations in order to provide information on colony activity and development. The accelerometers provide amplitude and frequency information which is recorded every three minutes and analysed for night time only. Vibrational data were validated by comparison to visual inspection data, particularly the brood development. We show a strong correlation between vibrational amplitude data and the brood cycle in the vicinity of the sensor. We have further explored the minimum data that is required, when frequency information is also included, to accurately predict the current point in the brood cycle. Such a technique should enable beekeepers to reduce the frequency with which visual inspections are required, reducing the stress this places on the colony and saving the beekeeper time.

  8. Explaining postnatal growth plasticity in a generalist brood parasite

    Science.gov (United States)

    Remeš, Vladimír

    2010-03-01

    Selection of a particular host has clear consequences for the performance of avian brood parasites. Experimental studies showed that growth rate and fledging mass of brood parasites varied between host species independently of the original host species. Finding correlates of this phenotypic plasticity in growth is important for assessing adaptiveness and potential fitness consequences of host choice. Here, I analyzed the effects of several host characteristics on growth rate and fledging mass of the young of brown-headed cowbird ( Molothrus ater), a generalist, non-evicting brood parasite. Cowbird chicks grew better in fast-developing host species and reached higher fledging mass in large hosts with fast postnatal development. A potential proximate mechanism linking fast growth and high fledging mass of cowbird with fast host development is superior food supply in fast-developing foster species. So far, we know very little about the consequences of the great plasticity in cowbird growth for later performance of the adult parasite. Thus, cowbird species could become interesting model systems for investigating the role of plasticity and optimization in the evolution of growth rate in birds.

  9. Are pheromones detected through the main olfactory epithelium?

    Science.gov (United States)

    Wang, Zhenshan; Nudelman, Aaron; Storm, Daniel R

    2007-06-01

    A major sensory organ for the detection of pheromones by animals is the vomeronasal organ (VNO). Although pheromones control the behaviors of various species, the effect of pheromones on human behavior has been controversial because the VNO is not functional in adults. However, recent genetic, biochemical, and electrophysiological data suggest that some pheromone-based behaviors, including male sexual behavior in mice, are mediated through the main olfactory epithelium (MOE) and are coupled to the type 3 adenylyl cyclase (AC3) and a cyclic nucleotide-gated (CNG) ion channel. These recent discoveries suggest the provocative hypothesis that human pheromones may signal through the MOE.

  10. [Biosynthesis and endocrine regulation of sex pheromones in moth].

    Science.gov (United States)

    Wang, Bo; Lin, Xin-da; Du, Yong-jun

    2015-10-01

    The crucial importance of sex pheromones in driving mating behaviors in moths has been well demonstrated in the process of sexual communication between individuals that produce and recognize species specific pheromones. Sex-pheromone molecules from different moth species are chemically characteristic, showing different terminal functional groups, various carbon chain lengths, different position and configuration of double bond system. This review summarized information on the biosynthetic pathways and enzymes involved in producing pheromone molecules in different moths. Then we listed the components and their ratios in the sex pheromones of 15 moth species belonging to different subfamilies in Noctuidae. We also discussed the various viewpoints regarding how sex pheromones with specific ratios are produced. In the discussion we attempted to classify the pheromone molecules based on their producers, characteristics of their functional groups and carbon chain lengths. In particular, composition and ratio variations of pheromones in closely related species or within a species were compared, and the possible molecular mechanisms for these variations and their evolutionary significance were discussed. Finally, we reviewed the endocrine regulation and signal transduction pathways, in which the pheromone biosynthesis activating neuropeptide (PBAN) is involved. Comparing the biosynthetic pathways of sex pheromones among different species, this article aimed to reveal the common principles in pheromone biosynthesis among moth species and the characteristic features associated with the evolutionary course of individual species. Subsequently, some future research directions were proposed.

  11. Methodology in structural determination and synthesis of insect pheromone

    Directory of Open Access Journals (Sweden)

    Guo-Qiang Lin

    1991-01-01

    Full Text Available By means of ethereal washing of insect pheromone glands of female moths, GC-MS detection along with microchemical reactions and electroantennogram (EAG survey, six economically important insect species were targeted for pheromone identification. The discovery of a natural pheromone inhibitor, chemo-selectivity and species isolation by pheromone will be described. The modified triple bond migration and triethylamine liganded vinyl cuprate were applied for achiral pheromone synthesis in double bond formation. Some optically active pheromones and their stereoisomers were synthesized through chiral pool or asymmetric synthesis. Some examples of chiral recognition of insects towards their chiral pheromones will be discussed. A CaH2 and silica gel catalyzed Sharpless Expoxidation Reaction was found in shortening the reaction time.

  12. Pheromones, sexual attractiveness and quality of life in menopausal women.

    Science.gov (United States)

    Cutler, W B; Genovese, E

    2002-06-01

    Pheromones, and their effects, are reviewed with a special emphasis on their potential contribution to sexual attractiveness in the menopause. Key topics included are biological functions of pheromones in animals and humans, the source of pheromones in humans, the axillary extract studies that led to the independent synthesis of pheromones, olfactory mechanisms for mediating pheromones, and aging, attractiveness and sexual dysfunction. Physical attractiveness is important for a better quality of life. Three separate, double-blind, placebo-controlled investigations, using the same protocol, all demonstrated that a synthesized pheromone, topically applied, increased sexual attractiveness. If partners are available, sexual attractiveness can increase affectionate intimate behavior, which, in turn, increases well-being and quality of life. More research is needed to address ways in which postmenopausal women can benefit from pheromones.

  13. Pheromones in marine algae: A technical approach

    Science.gov (United States)

    Gassmann, G.; Müller, D. G.; Fritz, P.

    1995-03-01

    It is now well known that many marine organisms use low-molecular volatile substances as signals, in order to coordinate activities between different individuals. The study of such pheromones requires the isolation and enrichment of the secretions from undisturbed living cells or organisms over extended periods of time. The Grob-Hersch extraction device, which we describe here, avoids adverse factors for the biological materials such as strong water currents, rising gas bubbles or chemical solvents. Furthermore, the formation of sea-water spray is greatly reduced. The application of this technique for the isolation of pheromones of marine algae and animals is described.

  14. Sex in the night: fatty acid-derived sex pheromones and corresponding membrane pheromone receptors in insects.

    Science.gov (United States)

    Koutroumpa, Fotini A; Jacquin-Joly, Emmanuelle

    2014-12-01

    The moth sex pheromone communication is one of the most striking examples of chemical communication in the animal kingdom. Investigating the molecular mechanisms of pheromone biosynthesis in the female pheromone gland and of pheromone reception in the male antennae not only defines new concepts in signalling research but also opens new perspectives for insect control. In this mini-review, we use the cotton leafworm Spodoptera littoralis as a guideline to illustrate the recent advances gained in the understanding of moth sex pheromone communication.

  15. Specific Cues Associated With Honey Bee Social Defence against Varroa destructor Infested Brood

    Science.gov (United States)

    Mondet, Fanny; Kim, Seo Hyun; de Miranda, Joachim R.; Beslay, Dominique; Le Conte, Yves; Mercer, Alison R.

    2016-01-01

    Social immunity forms an essential part of the defence repertoire of social insects. In response to infestation by the parasitic mite Varroa destructor and its associated viruses, honey bees (Apis mellifera L.) have developed a specific behaviour (varroa-sensitive hygiene, or VSH) that helps protect the colony from this parasite. Brood cells heavily infested with mites are uncapped, the brood killed, and the cell contents removed. For this extreme sacrifice to be beneficial to the colony, the targeting of parasitized brood for removal must be accurate and selective. Here we show that varroa-infested brood produce uniquely identifiable cues that could be used by VSH-performing bees to identify with high specificity which brood cells to sacrifice. This selective elimination of mite-infested brood is a disease resistance strategy analogous to programmed cell death, where young bees likely to be highly dysfunctional as adults are sacrificed for the greater good of the colony. PMID:27140530

  16. Cerambycid Beetle Species with Similar Pheromones are Segregated by Phenology and Minor Pheromone Components.

    Science.gov (United States)

    Mitchell, Robert F; Reagel, Peter F; Wong, Joseph C H; Meier, Linnea R; Silva, Weliton Dias; Mongold-Diers, Judith; Millar, Jocelyn G; Hanks, Lawrence M

    2015-05-01

    Recent research has shown that volatile sex and aggregation-sex pheromones of many species of cerambycid beetles are highly conserved, with sympatric and synchronic species that are closely related (i.e., congeners), and even more distantly related (different subfamilies), using the same or similar pheromones. Here, we investigated mechanisms by which cross attraction is averted among seven cerambycid species that are native to eastern North America and active as adults in spring: Anelaphus pumilus (Newman), Cyrtophorus verrucosus (Olivier), Euderces pini (Olivier), Neoclytus caprea (Say), and the congeners Phymatodes aereus (Newman), P. amoenus (Say), and P. varius (F.). Males of these species produce (R)-3-hydroxyhexan-2-one as their dominant or sole pheromone component. Our field bioassays support the hypothesis that cross attraction between species is averted or at least minimized by differences among species in seasonal phenology and circadian flight periods of adults, and/or by minor pheromone components that act as synergists for conspecifics and antagonists for heterospecifics.

  17. Darcin: a male pheromone that stimulates female memory and sexual attraction to an individual male's odour

    Directory of Open Access Journals (Sweden)

    McLean Lynn

    2010-06-01

    Full Text Available Abstract Background Among invertebrates, specific pheromones elicit inherent (fixed behavioural responses to coordinate social behaviours such as sexual recognition and attraction. By contrast, the much more complex social odours of mammals provide a broad range of information about the individual owner and stimulate individual-specific responses that are modulated by learning. How do mammals use such odours to coordinate important social interactions such as sexual attraction while allowing for individual-specific choice? We hypothesized that male mouse urine contains a specific pheromonal component that invokes inherent sexual attraction to the scent and which also stimulates female memory and conditions sexual attraction to the airborne odours of an individual scent owner associated with this pheromone. Results Using wild-stock house mice to ensure natural responses that generalize across individual genomes, we identify a single atypical male-specific major urinary protein (MUP of mass 18893Da that invokes a female's inherent sexual attraction to male compared to female urinary scent. Attraction to this protein pheromone, which we named darcin, was as strong as the attraction to intact male urine. Importantly, contact with darcin also stimulated a strong learned attraction to the associated airborne urinary odour of an individual male, such that, subsequently, females were attracted to the airborne scent of that specific individual but not to that of other males. Conclusions This involatile protein is a mammalian male sex pheromone that stimulates a flexible response to individual-specific odours through associative learning and memory, allowing female sexual attraction to be inherent but selective towards particular males. This 'darcin effect' offers a new system to investigate the neural basis of individual-specific memories in the brain and give new insights into the regulation of behaviour in complex social mammals. See associated

  18. Host response to cuckoo song is predicted by the future risk of brood parasitism

    OpenAIRE

    Kleindorfer, Sonia; Evans, Christine; Colombelli-Négrel, Diane; Robertson, Jeremy; Griggio, Matteo; Hoi, Herbert

    2013-01-01

    Introduction Risk assessment occurs over different temporal and spatial scales and is selected for when individuals show an adaptive response to a threat. Here, we test if birds respond to the threat of brood parasitism using the acoustical cues of brood parasites in the absence of visual stimuli. We broadcast the playback of song of three brood parasites (Chalcites cuckoo species) and a sympatric non-parasite (striated thornbill, Acanthiza lineata) in the territories of superb fairy-wrens (M...

  19. Habitat selection and movements of Piping Plover broods suggest a tradeoff between breeding stages

    Science.gov (United States)

    Wiltermuth, Mark T.; Anteau, Michael J.; Sherfy, Mark H.; Pearse, Aaron T.

    2015-01-01

    In precocial birds, adults select breeding areas using cues associated with habitat characteristics that are favorable for nesting success and chick survival, but there may be tradeoffs in habitat selection between these breeding stages. Here we describe habitat selection and intra-territory movements of 53 Piping Plover (Charadrius melodus) broods (320 observations) during the 2007–2008 breeding seasons on mainland- and island-shoreline habitats at Lake Sakakawea, North Dakota, USA. We used remotely sensed habitat characteristics to separately examine habitat selection and movements at two spatiotemporal scales to account for potential confounding effects of nest-site selection on brood-rearing habitat used. The scales used were (1) the entire brood-rearing period within available brood-rearing areas and (2) 2-day observation intervals within age-specific discrete habitat selection choice sets. Analyses at both scales indicated that broods selected areas which were non-vegetated, moderately level, and nearer to the shoreline. Rate of brood movement increased with age up to 5 days, then stabilized; broods that hatched >50 m away from the shoreline moved toward the shoreline. Brood movements were greater when they were in vegetated areas, when the brood-rearing area was of greater topographic complexity, and when broods aged 6–25 days were further away from the shoreline. Using inferences from our results and those of previously published work, we postulate how a potential tradeoff in habitat selection between nesting and brood-rearing can contribute to an ecological trap in a novel habitat. This work, in the context of published works, suggests that plover breeding habitat is a complex of both nesting and brood-rearing habitats and provides a basis for making remotely sensed abundance estimates of suitable breeding habitat for Piping Plovers.

  20. Pheromone binding proteins enhance the sensitivity of olfactory receptors to sex pheromones in Chilo suppressalis.

    Science.gov (United States)

    Chang, Hetan; Liu, Yang; Yang, Ting; Pelosi, Paolo; Dong, Shuanglin; Wang, Guirong

    2015-08-27

    Sexual communication in moths offers a simplified scenario to model and investigate insect sensory perception. Both PBPs (pheromone-binding proteins) and PRs (pheromone receptors) are involved in the detection of sex pheromones, but the interplay between them still remains largely unknown. In this study, we have measured the binding affinities of the four recombinant PBPs of Chilo suppressalis (CsupPBPs) to pheromone components and analogs and characterized the six PRs using the Xenopus oocytes expression system. Interestingly, when the responses of PRs were recorded in the presence of PBPs, we measured in several combinations a dramatic increase in signals as well as in sensitivity of such combined systems. Furthermore, the discrimination ability of appropriate combinations of PRs and PBPs was improved compared with the performance of PBPs or PRs alone. Besides further supporting a role of PBPs in the pheromone detection and discrimination, our data shows for the first time that appropriate combinations of PRs and PBPs improved the discrimination ability of PBPs or PRs alone. The variety of responses measured with different pairing of PBPs and PRs indicates the complexity of the olfaction system, which, even for the relatively simple task of detecting sex pheromones, utilises a highly sophisticated combinatorial approach.

  1. A new class of mealybug pheromones: a hemiterpene ester in the sex pheromone of Crisicoccus matsumotoi

    Science.gov (United States)

    Tabata, Jun; Narai, Yutaka; Sawamura, Nobuo; Hiradate, Syuntaro; Sugie, Hajime

    2012-07-01

    Mealybugs, which include several agricultural pests, are small sap feeders covered with a powdery wax. They exhibit clear sexual dimorphism; males are winged but fragile and short lived, whereas females are windless and less mobile. Thus, sex pheromones emitted by females facilitate copulation and reproduction by serving as a key navigation tool for males. Although the structures of the hitherto known mealybug pheromones vary among species, they have a common structural motif; they are carboxylic esters of monoterpene alcohols with irregular non-head-to-tail linkages. However, in the present study, we isolated from the Matsumoto mealybug, Crisicoccus matsumotoi (Siraiwa), a pheromone with a completely different structure. Using gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy, we identified the pheromone as 3-methyl-3-butenyl 5-methylhexanoate. Its attractiveness to males was confirmed in a series of field trapping experiments involving comparison between the isolated natural product and a synthetic sample. This is the first report of a hemiterpene mealybug pheromone. In addition, the acid moiety (5-methylhexanoate) appears to be rare in insect pheromones.

  2. Waptia and the Diversification of Brood Care in Early Arthropods.

    Science.gov (United States)

    Caron, Jean-Bernard; Vannier, Jean

    2016-01-11

    Brood care, including the carrying of eggs or juveniles, is a form of parental care, which, like other parental traits [1], enhances offspring fitness with variable costs and benefits to the parents [2]. Attempts to understand why and how parental care evolved independently in numerous animal groups often emphasize the role of environmental pressures such as predation, ephemeral resources, and, more generally, the harshness of environment. The fossil record can, in principle, provide minimum age constraints on the evolution of life-history traits, including brood care and key information on the reproductive strategies of extinct organisms. New, exceptionally preserved specimens of the weakly sclerotized arthropod Waptia fieldensis from the middle Cambrian (ca. 508 million years ago) Burgess Shale, Canada, provide the oldest example of in situ eggs with preserved embryos in the fossil record. The relatively small clutch size, up to 24 eggs, and the relatively large diameter of individual eggs, some over 2 mm, contrast with the high number of small eggs-found without preserved embryos-in the bivalved bradoriid arthropod Kunmingella douvillei from the Chengjiang biota (ca. 515 million years ago). The presence of these two different parental strategies suggests a rapid evolution of a variety of modern-type life-history traits, including extended investment in offspring survivorship, soon after the Cambrian emergence of animals. Together with previously described brooded eggs in ostracods from the Upper Ordovician (ca. 450 million years ago), these new findings suggest that the presence of a bivalved carapace played a key role in the early evolution of parental care in arthropods.

  3. Pest repelling properties of ant pheromones

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2014-01-01

    Ants control pests via predation and physical deterrence; however, ant communication is based on chemical cues which may serve as warning signals to potential prey and other intruders. The presence of ant pheromones may, thus, be sufficient to repel pests from ant territories. This mini...

  4. Moth pheromone receptors and deceitful parapheromones

    Science.gov (United States)

    The insect’s olfactory system is so selective that male moths, for example, can discriminate female-produced sex pheromones from compounds with minimal structural modifications. Yet, there is an exception for this “lock-and-key” tight selectivity. Formate analogs can be used as replacement for less ...

  5. Insect Control (1): Use of Pheromones

    Science.gov (United States)

    Marx, Jean L.

    1973-01-01

    Discusses current research relating to the use of pheromones as a means of controlling insect pests. These chemicals, which are secreted by insects to affect the behavior of other individuals of the same species, may be used to eliminate pests without destroying their predators and other beneficial insects. (JR)

  6. Regulation of ovulation by human pheromones.

    Science.gov (United States)

    Stern, K; McClintock, M K

    1998-03-12

    Pheromones are airborne chemical signals that are released by an individual into the environment and which affect the physiology or behaviour of other members of the same species. The idea that humans produce pheromones has excited the imagination of scientists and the public, leading to widespread claims for their existence, which, however, has remained unproven. Here we investigate whether humans produce compounds that regulate a specific neuroendocrine mechanism in other people without being consciously detected as odours (thereby fulfilling the classic definition of a pheromone). We found that odourless compounds from the armpits of women in the late follicular phase of their menstrual cycles accelerated the preovulatory surge of luteinizing hormone of recipient women and shortened their menstrual cycles. Axillary (underarm) compounds from the same donors which were collected later in the menstrual cycle (at ovulation) had the opposite effect: they delayed the luteinizing-hormone surge of the recipients and lengthened their menstrual cycles. By showing in a fully controlled experiment that the timing of ovulation can be manipulated, this study provides definitive evidence of human pheromones.

  7. Pest repellent properties of ant pheromones

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2012-01-01

    ant species (iii) Azteca instabilis and (iv) Camponotus textor reduce herbivory by flea beetles (Margaridisa sp.), whereas (v) deposits from Solenopsis geminata, did not lead to reduced herbivory. Further evidence for the impact of ant pheromones comes from studies showing that non-herbivorous ant...

  8. Male-male pheromone signalling in a lekking Drosophila.

    Science.gov (United States)

    Widemo, Fredrik; Johansson, Björn G

    2006-03-22

    Interest in sex pheromones has mainly been focused on mate finding, while relatively little attention has been given to the role of sex pheromones in mate choice and almost none to competition over mates. Here, we study male response to male pheromones in the lekking Drosophila grimshawi, where males deposit long-lasting pheromone streaks that attract males and females to the leks and influence mate assessment. We used two stocks of flies and both stocks adjusted their pheromone depositing behaviour in response to experimental manipulation, strongly indicating male ability to distinguish between competitors from qualitative differences in pheromone streaks alone. This is the first example of an insect distinguishing between individual odour signatures. Pheromone signalling influenced competition over mates, as males adjusted their investment in pheromone deposition in response to foreign pheromone streaks. Both sexes adapt their behaviour according to information from olfactory cues in D. grimshawi, but the relative benefits from male-female, as compared to male-male signalling, remain unknown. It seems likely that the pheromone signalling system originally evolved for attracting females to leks. The transition to a signalling system for conveying information about individuals may well, however, at least in part have been driven by benefits from male-male signalling.

  9. Sex pheromone biosynthetic pathways are conserved between moths and the butterfly Bicyclus anynana.

    Science.gov (United States)

    Liénard, Marjorie A; Wang, Hong-Lei; Lassance, Jean-Marc; Löfstedt, Christer

    2014-05-27

    Although phylogenetically nested within the moths, butterflies have diverged extensively in a number of life history traits. Whereas moths rely greatly on chemical signals, visual advertisement is the hallmark of mate finding in butterflies. In the context of courtship, however, male chemical signals are widespread in both groups although they likely have multiple evolutionary origins. Here, we report that in males of the butterfly Bicyclus anynana, courtship scents are produced de novo via biosynthetic pathways shared with females of many moth species. We show that two of the pheromone components that play a major role in mate choice, namely the (Z)-9-tetradecenol and hexadecanal, are produced through the activity of a fatty acyl Δ11-desaturase and two specialized alcohol-forming fatty acyl reductases. Our study provides the first evidence of conservation and sharing of ancestral genetic modules for the production of FA-derived pheromones over a long evolutionary timeframe thereby reconciling mate communication in moths and butterflies.

  10. Radar detection of drones responding to honeybee queen pheromone.

    Science.gov (United States)

    Loper, G M; Wolf, W W; Taylor, O R

    1993-09-01

    The response of honey bee (Apis mellifera L.) drones to queen pheromone(s) (either natural from a mated queen, or synthetic from a lure) was recorded using an X-band, ground-based radar. The distribution of drones (insect targets on the radar screen) changed from a scattered distribution to a line concentration (downwind) when the pheromone was released. Displacement within the line concentration was toward the pheromone. This response was seen as far as 800±15 m downwind from a lure with 10 mg of synthetic 9-oxodec-trans-2-enoic acid (9-ODA) and as far as 420±15 m from a mated queen. These studies demonstrate that queen pheromone can be detected by drones at much greater distances than previously believed and illustrate how X-band radar may be used to establish the distances at which insects of similar or larger size respond to pheromones.

  11. Pheromones in a superorganism: from gene to social regulation.

    Science.gov (United States)

    Alaux, C; Maisonnasse, A; Le Conte, Y

    2010-01-01

    Analogous to the importance of hormones in controlling organism homoeostasis, pheromones play a major role in the regulation of group homoeostasis at the social level. In social insects, pheromones coordinate the association of "unitary" organisms into a coherent social unit or so called "superorganism." For many years, honey bees have been a convincing model for studying pheromone regulation of social life. In addition, with the recent sequencing of its genome, a global view of pheromone communication is starting to emerge, and it is now possible to decipher this complex chemical language from the molecular to the social level. We review here the different pheromones regulating the main biological functions of the superorganism and detail their respective action on the genome, physiology and behavior of nestmates. Finally, we suggest some future research that may improve our understanding of the remarkably rich syntax of pheromone communication at the social level.

  12. Artificial Pheromone System Using RFID for Navigation of Autonomous Robots

    Institute of Scientific and Technical Information of China (English)

    Herianto; Toshiki Sakakibara; Daisuke Kurabayashi

    2007-01-01

    Navigation system based on the animal behavior has received a growing attention in the past few years. The navigation systems using artificial pheromone are still few so far. For this reason, this paper presents our research that aim to implement autonomous navigation with artificial pheromone system. By introducing artificial pheromone system composed of data carriers and autonomous robots, the robotic system creates a potential field to navigate their group. We have developed a pheromone density model to realize the function of pheromones with the help of data carriers. We intend to show the effectiveness of the proposed system by performing simulations and realization using modified mobile robot. The pheromone potential field system can be used for navigation of autonomous robots.

  13. Pheromone reception in moths: from molecules to behaviors.

    Science.gov (United States)

    Zhang, Jin; Walker, William B; Wang, Guirong

    2015-01-01

    Male moths detect and find their mates using species-specific sex pheromones emitted by conspecific females. Olfaction plays a vital role in this behavior. Since the first discovery of an insect sex pheromone from the silkmoth Bombyx mori, great efforts have been spent on understanding the sensing of the pheromones in vivo. Much progress has been made in elucidating the molecular mechanisms that mediate chemoreception in insects in the past few decades. In this review, we focus on pheromone reception and detection in moths, from the molecular to the behavioral level. We trace the information pathway from the capture of pheromone by male antennae, binding and transportation to olfactory receptor neurons, receptor activation, signal transduction, molecule inactivation, through brain processing and behavioral response. We highlight the impact of recent studies and also provide our insights into pheromone processing.

  14. Brood removal influences fall of Varroa destructor (Mesostigmata: Varroidae) in honey bee (Hymenoptera: Apidae) colonies

    Science.gov (United States)

    The hygienic removal of brood infested with Varroa destructor by Apis mellifera disrupts the reproduction of the infesting mites and exposes the foundress mites to potential removal from the colony by grooming. Using brood deliberately infested with marked Varroa, we investigated the association bet...

  15. Aggressive behavior of the male parent predicts brood sex ratio in a songbird

    Science.gov (United States)

    Szász, Eszter; Garamszegi, László Zsolt; Hegyi, Gergely; Szöllősi, Eszter; Markó, Gábor; Török, János; Rosivall, Balázs

    2014-08-01

    Brood sex ratio is often affected by parental or environmental quality, presumably in an adaptive manner that is the sex that confers higher fitness benefits to the mother is overproduced. So far, studies on the role of parental quality have focused on parental morphology and attractiveness. However, another aspect, the partner's behavioral characteristics, may also be expected to play a role in brood sex ratio adjustment. To test this hypothesis, we investigated whether the proportion of sons in the brood is predicted by the level of territorial aggression displayed by the father, in the collared flycatcher ( Ficedula albicollis). The proportion of sons in the brood was higher in early broods and increased with paternal tarsus length. When controlling for breeding date and body size, we found a higher proportion of sons in the brood of less aggressive fathers. Male nestlings are more sensitive to the rearing environment, and the behavior of courting males may often be used by females to assess their future parental activity. Therefore, adjusting brood sex ratio to the level of male aggression could be adaptive. Our results indicate that the behavior of the partner could indeed be a significant determinant in brood sex ratio adjustment, which should not be overlooked in future studies.

  16. Pheromone production in the butterfly Pieris napi L

    OpenAIRE

    Murtazina, Rushana

    2014-01-01

    Aphrodisiac and anti-aphrodisiac pheromone production and composition in the green-veined white butterfly Pieris napi L. were investigated. Aphrodisiac pheromone biosynthesis had different time constraints in butterflies from the diapausing and directly developing generations. Effects of stable isotope incorporation in adult butterfly pheromone, in the nectar and flower volatiles of  host plants from labeled substrates were measured by solid phase microextraction and gas chromatography–mass s...

  17. Quantitative analysis of pheromone-binding protein specificity

    OpenAIRE

    Katti, S.; Lokhande, N.; D González; Cassill, A.; Renthal, R

    2012-01-01

    Many pheromones have very low water solubility, posing experimental difficulties for quantitative binding measurements. A new method is presented for determining thermodynamically valid dissociation constants for ligands binding to pheromone-binding proteins (OBPs), using β-cyclodextrin as a solubilizer and transfer agent. The method is applied to LUSH, a Drosophila OBP that binds the pheromone 11-cis vaccenyl acetate (cVA). Refolding of LUSH expressed in E. coli was assessed by measuring N-p...

  18. A yeast pheromone-based inter-species communication system.

    Science.gov (United States)

    Hennig, Stefan; Clemens, André; Rödel, Gerhard; Ostermann, Kai

    2015-02-01

    We report on a pheromone-based inter-species communication system, allowing for a controlled cell-cell communication between the two species Saccharomyces cerevisiae and Schizosaccharomyces pombe as a proof of principle. It exploits the mating response pathways of the two yeast species employing the pheromones, α- or P-factor, as signaling molecules. The authentic and chimeric pheromone-encoding genes were engineered to code for the P-factor in S. cerevisiae and the α-factor in S. pombe. Upon transformation of the respective constructs, cells were enabled to express the mating pheromone of the opposite species. The supernatant of cultures of S. pombe cells expressing α-factor were able to induce a G1 arrest in the cell cycle, a change in morphology to the typical shmoo effect and expression driven by the pheromone-responsive FIG1 promoter in S. cerevisiae. The supernatant of cultures of S. cerevisiae cells expressing P-factor similarly induced cell cycle arrest in G1, an alteration in morphology typical for mating as well as the activation of the pheromone-responsive promoters of the rep1 and sxa2 genes in a pheromone-hypersensitive reporter strain of S. pombe. Apparently, both heterologous pheromones were correctly processed and secreted in an active form by the cells of the other species. Our data clearly show that the species-specific pheromone systems of yeast species can be exploited for a controlled inter-species communication.

  19. Neuroendocrinology briefings 11: pheromones and reproduction.

    Science.gov (United States)

    Keverne, E B

    2000-11-01

    The information humans receive from their nose is rarely of vital significance and although perfumers and masters of wine have developed a large vocabulary of descriptors, most of us categorize odours into pleasant and unpleasant. Not surprisingly therefore, most of our olfactory receptor genes are nonfunctional pseudogenes. Rodents, on the other hand, not only have a vast repertoire of olfactory genes (1000-1500) but also possess two additional sets of receptors in the vomeronasal organ that is specialized for pheromone reception.

  20. How much is a pheromone worth?

    Science.gov (United States)

    Bento, Jose Mauricio S; Parra, Jose Roberto P; de Miranda, Silvia H G; Adami, Andrea C O; Vilela, Evaldo F; Leal, Walter S

    2016-01-01

    Pheromone-baited traps have been widely used in integrated pest management programs, but their economic value for growers has never been reported.  We analyzed the economic benefits of long-term use of traps baited with the citrus fruit borer Gymnandrosoma aurantianum sex pheromone in Central-Southern Brazil. Our analysis show that from 2001 to 2013 citrus growers avoided accumulated pest losses of 132.7 million to 1.32 billion USD in gross revenues, considering potential crop losses in the range of 5 to 50%. The area analyzed, 56,600 to 79,100 hectares of citrus (20.4 to 29.4 million trees), corresponds to 9.7 to 13.5% of the total area planted with citrus in the state of São Paulo. The data show a benefit-to-cost ratio of US$ 2,655 to US$ 26,548 per dollar spent on research with estimated yield loss prevented in the range of 5-50%, respectively. This study demonstrates that, in addition to the priceless benefits for the environment, sex pheromones are invaluable tools for growers as their use for monitoring populations allows rational and reduced use of insecticides, a win-win situation.

  1. Expression of acetylcholinesterase 1 is associated with brood rearing status in the honey bee, Apis mellifera

    Science.gov (United States)

    Kim, Young Ho; Kim, Ju Hyeon; Kim, Kyungmun; Lee, Si Hyeock

    2017-01-01

    Acetylcholinesterase 1 (AmAChE1) of the honey bee, Apis mellifera, has been suggested to have non-neuronal functions. A systematic expression profiling of AmAChE1 over a year-long cycle on a monthly basis revealed that AmAChE1 was predominantly expressed in both head and abdomen during the winter months and was moderately expressed during the rainy summer months. Interestingly, AmAChE1 expression was inhibited when bees were stimulated for brood rearing by placing overwintering beehives in strawberry greenhouses with a pollen diet, whereas it resumed when the beehives were moved back to the cold field, thereby suppressing brood rearing. In early spring, pollen diet supplementation accelerated the induction of brood-rearing activity and the inhibition of AmAChE1 expression. When active beehives were placed in a screen tent in late spring, thereby artificially suppressing brood-rearing activity, AmAChE1 was highly expressed. In contrast, AmAChE1 expression was inhibited when beehives were allowed to restore brood rearing by removing the screen, supporting the hypothesis that brood rearing status is a main factor in the regulation of AmAChE1 expression. Since brood rearing status is influenced by various stress factors, including temperature and diet shortage, our finding discreetly suggests that AmAChE1 is likely involved in the stress response or stress management. PMID:28045085

  2. The mode of evolution of aggregation pheromones in Drosophila species

    NARCIS (Netherlands)

    Symonds, MRE; Wertheim, B

    2005-01-01

    Aggregation pheromones are used by fruit flies of the genus Drosophila to assemble on breeding substrates, where they feed, mate and oviposit communally. These pheromones consist of species-specific blends of chemicals. Here, using a phylogenetic framework, we examine how differences among species i

  3. A Predictive Model for Yeast Cell Polarization in Pheromone Gradients.

    Science.gov (United States)

    Muller, Nicolas; Piel, Matthieu; Calvez, Vincent; Voituriez, Raphaël; Gonçalves-Sá, Joana; Guo, Chin-Lin; Jiang, Xingyu; Murray, Andrew; Meunier, Nicolas

    2016-04-01

    Budding yeast cells exist in two mating types, a and α, which use peptide pheromones to communicate with each other during mating. Mating depends on the ability of cells to polarize up pheromone gradients, but cells also respond to spatially uniform fields of pheromone by polarizing along a single axis. We used quantitative measurements of the response of a cells to α-factor to produce a predictive model of yeast polarization towards a pheromone gradient. We found that cells make a sharp transition between budding cycles and mating induced polarization and that they detect pheromone gradients accurately only over a narrow range of pheromone concentrations corresponding to this transition. We fit all the parameters of the mathematical model by using quantitative data on spontaneous polarization in uniform pheromone concentration. Once these parameters have been computed, and without any further fit, our model quantitatively predicts the yeast cell response to pheromone gradient providing an important step toward understanding how cells communicate with each other.

  4. Semi-selective fatty acyl reductases from four heliothine moths influence the specific pheromone composition

    NARCIS (Netherlands)

    Hagström, Å.K; Liénard, M.A.; Groot, A.T.; Hedenström, E; Löfstedt, C.

    2012-01-01

    Background: Sex pheromones are essential in moth mate communication. Information on pheromone biosynthetic genes and enzymes is needed to comprehend the mechanisms that contribute to specificity of pheromone signals. Most heliothine moths use sex pheromones with (Z)-11-hexadecenal as the major compo

  5. Insect pheromones: An overview of function, form, and discovery.

    Science.gov (United States)

    Yew, Joanne Y; Chung, Henry

    2015-07-01

    For many species of insects, lipid pheromones profoundly influence survival, reproduction, and social organization. Unravelling the chemical language of insects has been the subject of intense research in the field of chemical ecology for the past five decades. Characterizing the forms, functions, and biosynthesis of lipid pheromones has led not only to the development of strategies for controlling agricultural pests but has also provided insights into fundamental questions in evolutionary biology. Despite the enormous variety of chemical structures that are used as pheromones, some common themes in function and biosynthetic pathways have emerged across studies of diverse taxa. This review will offer a general overview of insect lipid pheromone function and biochemical synthesis, describe analytical methods for pheromone discovery, and provide perspectives on the contribution of chemical ecology to pest control and understanding evolutionary processes.

  6. Sex and Aggregation-Sex Pheromones of Cerambycid Beetles: Basic Science and Practical Applications.

    Science.gov (United States)

    Hanks, Lawrence M; Millar, Jocelyn G

    2016-07-01

    Research since 2004 has shown that the use of volatile attractants and pheromones is widespread in the large beetle family Cerambycidae, with pheromones now identified from more than 100 species, and likely pheromones for many more. The pheromones identified to date from species in the subfamilies Cerambycinae, Spondylidinae, and Lamiinae are all male-produced aggregation-sex pheromones that attract both sexes, whereas all known examples for species in the subfamilies Prioninae and Lepturinae are female-produced sex pheromones that attract only males. Here, we summarize the chemistry of the known pheromones, and the optimal methods for their collection, analysis, and synthesis. Attraction of cerambycids to host plant volatiles, interactions between their pheromones and host plant volatiles, and the implications of pheromone chemistry for invasion biology are discussed. We also describe optimized traps, lures, and operational parameters for practical applications of the pheromones in detection, sampling, and management of cerambycids.

  7. Nest enlargement in leaf-cutting ants: relocated brood and fungus trigger the excavation of new chambers.

    Directory of Open Access Journals (Sweden)

    Daniela Römer

    Full Text Available During colony growth, leaf-cutting ants enlarge their nests by excavating tunnels and chambers housing their fungus gardens and brood. Workers are expected to excavate new nest chambers at locations across the soil profile that offer suitable environmental conditions for brood and fungus rearing. It is an open question whether new chambers are excavated in advance, or will emerge around brood or fungus initially relocated to a suitable site in a previously-excavated tunnel. In the laboratory, we investigated the mechanisms underlying the excavation of new nest chambers in the leaf-cutting ant Acromyrmex lundi. Specifically, we asked whether workers relocate brood and fungus to suitable nest locations, and to what extent the relocated items trigger the excavation of a nest chamber and influence its shape. When brood and fungus were exposed to unfavorable environmental conditions, either low temperatures or low humidity, both were relocated, but ants clearly preferred to relocate the brood first. Workers relocated fungus to places containing brood, demonstrating that subsequent fungus relocation spatially follows the brood deposition. In addition, more ants aggregated at sites containing brood. When presented with a choice between two otherwise identical digging sites, but one containing brood, ants' excavation activity was higher at this site, and the shape of the excavated cavity was more rounded and chamber-like. The presence of fungus also led to the excavation of rounder shapes, with higher excavation activity at the site that also contained brood. We argue that during colony growth, workers preferentially relocate brood to suitable locations along a tunnel, and that relocated brood spatially guides fungus relocation and leads to increased digging activity around them. We suggest that nest chambers are not excavated in advance, but emerge through a self-organized process resulting from the aggregation of workers and their density

  8. Nest enlargement in leaf-cutting ants: relocated brood and fungus trigger the excavation of new chambers.

    Science.gov (United States)

    Römer, Daniela; Roces, Flavio

    2014-01-01

    During colony growth, leaf-cutting ants enlarge their nests by excavating tunnels and chambers housing their fungus gardens and brood. Workers are expected to excavate new nest chambers at locations across the soil profile that offer suitable environmental conditions for brood and fungus rearing. It is an open question whether new chambers are excavated in advance, or will emerge around brood or fungus initially relocated to a suitable site in a previously-excavated tunnel. In the laboratory, we investigated the mechanisms underlying the excavation of new nest chambers in the leaf-cutting ant Acromyrmex lundi. Specifically, we asked whether workers relocate brood and fungus to suitable nest locations, and to what extent the relocated items trigger the excavation of a nest chamber and influence its shape. When brood and fungus were exposed to unfavorable environmental conditions, either low temperatures or low humidity, both were relocated, but ants clearly preferred to relocate the brood first. Workers relocated fungus to places containing brood, demonstrating that subsequent fungus relocation spatially follows the brood deposition. In addition, more ants aggregated at sites containing brood. When presented with a choice between two otherwise identical digging sites, but one containing brood, ants' excavation activity was higher at this site, and the shape of the excavated cavity was more rounded and chamber-like. The presence of fungus also led to the excavation of rounder shapes, with higher excavation activity at the site that also contained brood. We argue that during colony growth, workers preferentially relocate brood to suitable locations along a tunnel, and that relocated brood spatially guides fungus relocation and leads to increased digging activity around them. We suggest that nest chambers are not excavated in advance, but emerge through a self-organized process resulting from the aggregation of workers and their density-dependent digging behavior

  9. Malheur NWR: Initial Survey Instructions for Impoundment Waterfowl Brood Use Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The objective of this survey is to monitor waterfowl brood use and number in association with water management and drawdowns of impoundments (including associated...

  10. An evaluation of the possible adaptive function of fungal brood covering by attine ants

    DEFF Research Database (Denmark)

    Armitage, Sophie Alice Octavia; Fernández-Marín, Hermógenes; Wcislo, William T.;

    2012-01-01

    Fungus-growing ants (Myrmicinae: Attini) live in an obligate symbiotic relationship with a fungus that they rear for food, but they can also use the fungal mycelium to cover their brood. We surveyed colonies from 20 species of fungus-growing ants and show that brood-covering behavior occurs in most...... species, but to varying degrees, and appears to have evolved shortly after the origin of fungus farming, but was partly or entirely abandoned in some genera. To understand the evolution of the trait we used quantitative phylogenetic analyses to test whether brood-covering behavior covaries among attine...... ant clades and with two hygienic traits that reduce risk of disease: mycelial brood cover did not correlate with mutualistic bacteria that the ants culture on their cuticles for their antibiotics, but there was a negative relationship between metapleural gland grooming and mycelial cover. A broader...

  11. Kanuti NWR waterfowl brood survey of Kanuti River, 7/11/85-7/21/85

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This year's brood count very likely gives a more thorough inventory of lake production than do the last two year's counts: whereas most lakes were spot surveyed from...

  12. Social regulation of aggression by pheromonal activation of Or65a olfactory neurons in Drosophila.

    Science.gov (United States)

    Liu, Weiwei; Liang, Xinhua; Gong, Jianxian; Yang, Zhen; Zhang, Yao-Hua; Zhang, Jian-Xu; Rao, Yi

    2011-06-19

    When two socially naive Drosophila males meet, they will fight. However, prior social grouping of males reduces their aggression. We found olfactory communication to be important for modulating Drosophila aggression. Although acute exposure to the male-specific pheromone 11-cis-vaccenyl acetate (cVA) elicited aggression through Or67d olfactory receptor neurons (ORNs), chronic cVA exposure reduced aggression through Or65a ORNs. Or65a ORNs were not acutely involved in aggression, but blockade of synaptic transmission of Or65a ORNs during social grouping or prior chronic cVA exposure eliminated social modulation of aggression. Artificial activation of Or65a ORNs by ectopic expression of the Drosophila gene TrpA1 was sufficient to reduce aggression. Social suppression of aggression requires subsets of local interneurons in the antennal lobe. Our results indicate that activation of Or65a ORNs is important for social modulation of male aggression, demonstrate that the acute and chronic effects of a single pheromone are mediated by two distinct types of ORNs, reveal a behaviorally important role for interneurons and suggest a chemical method to reduce aggression in animals.

  13. The GPCR membrane receptor, DopEcR, mediates the actions of both dopamine and ecdysone to control sex pheromone perception in an insect

    Directory of Open Access Journals (Sweden)

    Antoine eAbrieux

    2014-09-01

    Full Text Available Olfactory information mediating sexual behavior is crucial for reproduction in many animals, including insects. In male moths, the macroglomerular complex of the primary olfactory center, the antennal lobe (AL is specialized in the treatment of information on the female-emitted sex pheromone. Evidence is accumulating that modulation of behavioral pheromone responses occurs through neuronal plasticity via the action of hormones and/or catecholamines. We recently showed that a G-protein-coupled receptor (GPCR, AipsDopEcR, with its homologue known in Drosophila for its double affinity to the main insect steroid hormone 20-hydroxyecdysone (20E, and dopamine (DA, present in the ALs, is involved in the behavioral response to pheromone in the moth, Agrotis ipsilon. Here we tested the role of AipsDopEcR as compared to nuclear 20E receptors in central pheromone processing combining receptor inhibition with intracellular recordings of AL neurons. We show that the sensitivity of AL neurons for the pheromone in males decreases strongly after AipsDopEcR-dsRNA injection but also after inhibition of nuclear 20E receptors. Moreover we tested the involvement of 20E and DA in the receptor-mediated behavioral modulation in wind tunnel experiments, using ligand applications and receptor inhibition treatments. We show that both ligands are necessary and act on AipsDopEcR-mediated behavior. Altogether these results indicate that the GPCR membrane receptor, AipsDopEcR, controls sex pheromone perception through the action of both 20E and DA in the central nervous system, probably in concert with 20E action through nuclear receptors.

  14. Baby Killers: Documentation and Evolution of Scuttle Fly (Diptera: Phoridae) Parasitism of Ant (Hymenoptera: Formicidae) Brood

    OpenAIRE

    Brown, Brian; Hash, John; Hartop, Emily; Porras, Wendy; Amorim, Dalton

    2017-01-01

    Numerous well-documented associations occur among species of scuttle flies (Diptera: Phoridae) and ants (Hymenoptera: Formicidae), but examples of brood parasitism are rare and the mechanisms of parasitism often remain unsubstantiated. We present two video-documented examples of ant brood (larvae and pupae) parasitism by scuttle flies. In footage from Estação Biológica de Boracéia in Brazil, adult females of Ceratoconus setipennis Borgmeier can be seen attacking workers of Linepithema h...

  15. Brood Parasitism in Asian Cuckoos: Different Aspects of Interactions between Cuckoos and their Hosts in Bangladesh

    OpenAIRE

    Begum, Sajeda

    2011-01-01

    The interaction between brood parasitic cuckoos and their hosts represents a traditional example of coevolution, whereby obligate interspecific brood parasitic cuckoos completely rely on their hosts to do their parental care for them by laying their eggs in the host’s nest. This thesis brings together a great deal of information documenting and clarifying the interactions between different species of hosts and their respective parasitic cuckoos in Bangladesh. I recorded parasitism rates to de...

  16. Pheromones from males of different familiarity exert divergent effects on adult neurogenesis in the female accessory olfactory bulb.

    Science.gov (United States)

    Wu, Jyun-Han; Han, Yueh-Ting; Yu, Jenn-Yah; Wang, Tsu-Wei

    2013-08-01

    Pheromones from urine of unfamiliar conspecific male animals can reinitiate a female's estrus cycle to cause pregnancy block through the vomeronasal organ (VNO)-accessory olfactory bulb (AOB)-hypothalamic pathway. This phenomenon is called the Bruce effect. Pheromones from the mate of the female, however, do not trigger re-entrance of the estrus cycle because an olfactory memory toward its mate is formed. The activity of the VNO-AOB-hypothalamic pathway is negatively modulated by GABAergic granule cells in the AOB. Since these cells are constantly replenished by neural stem cells in the subventricular zone (SVZ) of the lateral ventricle throughout adulthood and adult neurogenesis is required for mate recognition and fertility, we tested the hypothesis that pheromones from familiar and unfamiliar males may have different effects on adult AOB neurogenesis in female mice. When female mice were exposed to bedding used by a male or lived with one, cell proliferation and neuroblast production in the SVZ were increased. Furthermore, survival of newly generated cells in the AOB was enhanced. This survival effect was transient and mediated by norepinephrine. Interestingly, male bedding-induced newborn cell survival in the AOB but not cell proliferation in the SVZ was attenuated when females were subjected to bedding from an unfamiliar male. Our results indicate that male pheromones from familiar and unfamiliar males exert different effects on neurogenesis in the adult female AOB. Given that adult neurogenesis is required for reproductive behaviors, these divergent pheromonal effects may provide a mechanism for the Bruce effect. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 73: 632-645, 2013.

  17. Multiple length peptide-pheromone variants produced by Streptococcus pyogenes directly bind Rgg proteins to confer transcriptional regulation.

    Science.gov (United States)

    Aggarwal, Chaitanya; Jimenez, Juan Cristobal; Nanavati, Dhaval; Federle, Michael J

    2014-08-08

    Streptococcus pyogenes, a human-restricted pathogen, accounts for substantial mortality related to infections worldwide. Recent studies indicate that streptococci produce and respond to several secreted peptide signaling molecules (pheromones), including those known as short hydrophobic peptides (SHPs), to regulate gene expression by a quorum-sensing mechanism. Upon transport into the bacterial cell, pheromones bind to and modulate activity of receptor proteins belonging to the Rgg family of transcription factors. Previously, we reported biofilm regulation by the Rgg2/3 quorum-sensing circuit in S. pyogenes. The aim of this study was to identify the composition of mature pheromones from cell-free culture supernatants that facilitate biofilm formation. Bioluminescent reporters were employed to detect active pheromones in culture supernatants fractionated by reverse-phase chromatography, and mass spectrometry was used to characterize their properties. Surprisingly, multiple SHPs that varied by length were detected. Synthetic peptides of each variant were tested individually using bioluminescence reporters and biofilm growth assays, and although activities differed widely among the group, peptides comprising the C-terminal eight amino acids of the full-length native peptide were most active. Direct Rgg/SHP interactions were determined using a fluorescence polarization assay that utilized FITC-labeled peptide ligands. Peptide receptor affinities were seen to be as low as 500 nm and their binding affinities directly correlated with observed bioactivity. Revelation of naturally produced pheromones along with determination of their affinity for cognate receptors are important steps forward in designing compounds whose purpose is positioned for future therapeutics aimed at treating infections through the interference of bacterial communication.

  18. Depressive rumination and past depression in Japanese university students: comparison of brooding and reflection.

    Science.gov (United States)

    Hasegawa, Akira; Koda, Munenaga; Hattori, Yosuke; Kondo, Tsuyoshi; Kawaguchi, Jun

    2014-06-01

    The Ruminative Responses Scale, a measure of depressive rumination, contains two subscales: Brooding and Reflection. Treynor, Gonzalez, and Nolen-Hoeksema (2003) proposed that Brooding is maladaptive and Reflection is adaptive. This article examined the relationships among Brooding, Reflection, and previous depression in two samples of Japanese undergraduates, who were non-depressed at the time of their participation. Based on answers to a self-report measure, participants were divided into a formerly depressed group, who had experienced an episode that met the criteria for major depression, and a never-depressed group. Logistic regression analyses were conducted with Brooding, Reflection, and current depression as the independent variables and past depression as the dependent variable. Brooding had consistent positive associations with past depression. The relationship between Reflection and past depression was not significant for one sample, but was statistically significant and positive in the second sample. In the second sample, Brooding and Reflection both were related with past depression after controlling for worry.

  19. Mobbing and sitting tight at the nest as methods of avoiding brood parasitism.

    Science.gov (United States)

    Rands, Sean A

    2012-04-06

    The arms race between brood parasites and their hosts has led to many different host behaviours for avoiding parasitism. Some of these behaviours are social, and require the presence of conspecifics to work effectively: in response to alarm calls, some species engage in mobbing behaviour where neighbours join nest tenants in attacking and repelling an invading brood parasite. There are risks involved for the neighbours, but it has been demonstrated that social mobbing allows individuals to learn about the presence of brood parasites in the environment, suggesting that social learning is occurring. Here, I consider whether using social signals to alert naive individuals to the presence of brood parasites is a suitable strategy, compared with sitting tight on the nest in response to the signal (which should reduce the chances of being parasitized). I also compare the efficiency of these strategies with the case where individuals fail to change behaviour in response a brood parasite. Using an individual-based simulation model, I demonstrate that both mobbing and sitting tight are effective strategies in response to a signal, and that mobbing is more effective when the chances of being parasitized increase. These results are discussed and compared with known host-brood parasite relationships.

  20. Drone and Worker Brood Microclimates Are Regulated Differentially in Honey Bees, Apis mellifera.

    Directory of Open Access Journals (Sweden)

    Zhiyong Li

    Full Text Available Honey bee (Apis mellifera drones and workers show differences in morphology, physiology, and behavior. Because the functions of drones are more related to colony reproduction, and those of workers relate to both survival and reproduction, we hypothesize that the microclimate for worker brood is more precisely regulated than that of drone brood.We assessed temperature and relative humidity (RH inside honey bee colonies for both drone and worker brood throughout the three-stage development period, using digital HOBO® Data Loggers. The major findings of this study are that 1 both drone and worker castes show the highest temperature for eggs, followed by larvae and then pupae; 2 temperature in drones are maintained at higher precision (smaller variance in drone eggs and larvae, but at a lower precision in pupae than the corresponding stages of workers; 3 RH regulation showed higher variance in drone than workers across all brood stages; and 4 RH regulation seems largely due to regulation by workers, as the contribution from empty honey combs are much smaller compared to that from adult workers.We conclude that honey bee colonies maintain both temperature and humidity actively; that the microclimate for sealed drone brood is less precisely regulated than worker brood; and that combs with honey contribute very little to the increase of RH in honey bee colonies. These findings increase our understanding of microclimate regulation in honey bees and may have implications for beekeeping practices.

  1. Drone and Worker Brood Microclimates Are Regulated Differentially in Honey Bees, Apis mellifera

    Science.gov (United States)

    Li, Zhiyong; Huang, Zachary Y.; Sharma, Dhruv B.; Xue, Yunbo; Wang, Zhi; Ren, Bingzhong

    2016-01-01

    Background Honey bee (Apis mellifera) drones and workers show differences in morphology, physiology, and behavior. Because the functions of drones are more related to colony reproduction, and those of workers relate to both survival and reproduction, we hypothesize that the microclimate for worker brood is more precisely regulated than that of drone brood. Methodology/Principal Findings We assessed temperature and relative humidity (RH) inside honey bee colonies for both drone and worker brood throughout the three-stage development period, using digital HOBO® Data Loggers. The major findings of this study are that 1) both drone and worker castes show the highest temperature for eggs, followed by larvae and then pupae; 2) temperature in drones are maintained at higher precision (smaller variance) in drone eggs and larvae, but at a lower precision in pupae than the corresponding stages of workers; 3) RH regulation showed higher variance in drone than workers across all brood stages; and 4) RH regulation seems largely due to regulation by workers, as the contribution from empty honey combs are much smaller compared to that from adult workers. Conclusions/Significance We conclude that honey bee colonies maintain both temperature and humidity actively; that the microclimate for sealed drone brood is less precisely regulated than worker brood; and that combs with honey contribute very little to the increase of RH in honey bee colonies. These findings increase our understanding of microclimate regulation in honey bees and may have implications for beekeeping practices. PMID:26882104

  2. Brood parasites lay eggs matching the appearance of host clutches.

    Science.gov (United States)

    Honza, Marcel; Šulc, Michal; Jelínek, Václav; Požgayová, Milica; Procházka, Petr

    2014-01-07

    Interspecific brood parasitism represents a prime example of the coevolutionary arms race where each party has evolved strategies in response to the other. Here, we investigated whether common cuckoos (Cuculus canorus) actively select nests within a host population to match the egg appearance of a particular host clutch. To achieve this goal, we quantified the degree of egg matching using the avian vision modelling approach. Randomization tests revealed that cuckoo eggs in naturally parasitized nests showed lower chromatic contrast to host eggs than those assigned randomly to other nests with egg-laying date similar to naturally parasitized clutches. Moreover, egg matching in terms of chromaticity was better in naturally parasitized nests than it would be in the nests of the nearest active non-parasitized neighbour. However, there was no indication of matching in achromatic spectral characteristics whatsoever. Thus, our results clearly indicate that cuckoos select certain host nests to increase matching of their own eggs with host clutches, but only in chromatic characteristics. Our results suggest that the ability of cuckoos to actively choose host nests based on the eggshell appearance imposes a strong selection pressure on host egg recognition.

  3. Analysis of male pheromones that accelerate female reproductive organ development.

    Science.gov (United States)

    Flanagan, Kelly A; Webb, William; Stowers, Lisa

    2011-02-08

    Male odors can influence a female's reproductive physiology. In the mouse, the odor of male urine results in an early onset of female puberty. Several volatile and protein pheromones have previously been reported to each account for this bioactivity. Here we bioassay inbred BALB/cJ females to study pheromone-accelerated uterine growth, a developmental hallmark of puberty. We evaluate the response of wild-type and mutant mice lacking a specialized sensory transduction channel, TrpC2, and find TrpC2 function to be necessary for pheromone-mediated uterine growth. We analyze the relative effectiveness of pheromones previously identified to accelerate puberty through direct bioassay and find none to significantly accelerate uterine growth in BALB/cJ females. Complementary to this analysis, we have devised a strategy of partial purification of the uterine growth bioactivity from male urine and applied it to purify bioactivity from three different laboratory strains. The biochemical characteristics of the active fraction of all three strains are inconsistent with that of previously known pheromones. When directly analyzed, we are unable to detect previously known pheromones in urine fractions that generate uterine growth. Our analysis indicates that pheromones emitted by males to advance female puberty remain to be identified.

  4. Analysis of male pheromones that accelerate female reproductive organ development.

    Directory of Open Access Journals (Sweden)

    Kelly A Flanagan

    Full Text Available Male odors can influence a female's reproductive physiology. In the mouse, the odor of male urine results in an early onset of female puberty. Several volatile and protein pheromones have previously been reported to each account for this bioactivity. Here we bioassay inbred BALB/cJ females to study pheromone-accelerated uterine growth, a developmental hallmark of puberty. We evaluate the response of wild-type and mutant mice lacking a specialized sensory transduction channel, TrpC2, and find TrpC2 function to be necessary for pheromone-mediated uterine growth. We analyze the relative effectiveness of pheromones previously identified to accelerate puberty through direct bioassay and find none to significantly accelerate uterine growth in BALB/cJ females. Complementary to this analysis, we have devised a strategy of partial purification of the uterine growth bioactivity from male urine and applied it to purify bioactivity from three different laboratory strains. The biochemical characteristics of the active fraction of all three strains are inconsistent with that of previously known pheromones. When directly analyzed, we are unable to detect previously known pheromones in urine fractions that generate uterine growth. Our analysis indicates that pheromones emitted by males to advance female puberty remain to be identified.

  5. Functionality of the Paracoccidioides mating α-pheromone-receptor system.

    Directory of Open Access Journals (Sweden)

    Jéssica A Gomes-Rezende

    Full Text Available Recent evidence suggests that Paracoccidioides species have the potential to undergo sexual reproduction, although no sexual cycle has been identified either in nature or under laboratory conditions. In the present work we detected low expression levels of the heterothallic MAT loci genes MAT1-1 and MAT1-2, the α-pheromone (PBα gene, and the α- and a-pheromone receptor (PREB and PREA genes in yeast and mycelia forms of several Paracoccidioides isolates. None of the genes were expressed in a mating type dependent manner. Stimulation of P. brasiliensis MAT1-2 strains with the synthetic α-pheromone peptide failed to elicit transcriptional activation of MAT1-2, PREB or STE12, suggesting that the strains tested are insensitive to α-pheromone. In order to further evaluate the biological functionality of the pair α-pheromone and its receptor, we took advantage of the heterologous expression of these Paracoccidioides genes in the corresponding S. cerevisiae null mutants. We show that S. cerevisiae strains heterologously expressing PREB respond to Pbα pheromone either isolated from Paracoccidioides culture supernatants or in its synthetic form, both by shmoo formation and by growth and cell cycle arrests. This allowed us to conclude that Paracoccidioides species secrete an active α-pheromone into the culture medium that is able to activate its cognate receptor. Moreover, expression of PREB or PBα in the corresponding null mutants of S. cerevisiae restored mating in these non-fertile strains. Taken together, our data demonstrate pheromone signaling activation by the Paracoccidioides α-pheromone through its receptor in this yeast model, which provides novel evidence for the existence of a functional mating signaling system in Paracoccidioides.

  6. Genomewide identification of pheromone-targeted transcription in fission yeast

    Directory of Open Access Journals (Sweden)

    Wright Anthony

    2006-11-01

    Full Text Available Abstract Background Fission yeast cells undergo sexual differentiation in response to nitrogen starvation. In this process haploid M and P cells first mate to form diploid zygotes, which then enter meiosis and sporulate. Prior to mating, M and P cells communicate with diffusible mating pheromones that activate a signal transduction pathway in the opposite cell type. The pheromone signalling orchestrates mating and is also required for entry into meiosis. Results Here we use DNA microarrays to identify genes that are induced by M-factor in P cells and by P-factor in M-cells. The use of a cyr1 genetic background allowed us to study pheromone signalling independently of nitrogen starvation. We identified a total of 163 genes that were consistently induced more than two-fold by pheromone stimulation. Gene disruption experiments demonstrated the involvement of newly discovered pheromone-induced genes in the differentiation process. We have mapped Gene Ontology (GO categories specifically associated with pheromone induction. A direct comparison of the M- and P-factor induced expression pattern allowed us to identify cell-type specific transcripts, including three new M-specific genes and one new P-specific gene. Conclusion We found that the pheromone response was very similar in M and P cells. Surprisingly, pheromone control extended to genes fulfilling their function well beyond the point of entry into meiosis, including numerous genes required for meiotic recombination. Our results suggest that the Ste11 transcription factor is responsible for the majority of pheromone-induced transcription. Finally, most cell-type specific genes now appear to be identified in fission yeast.

  7. A pheromone outweighs temperature in influencing migration of sea lamprey

    Science.gov (United States)

    Brant, Cory O.; Li, Ke; Johnson, Nicholas S.; Li, Weiming

    2015-01-01

    Organisms continuously acquire and process information from surrounding cues. While some cues complement one another in delivering more reliable information, others may provide conflicting information. How organisms extract and use reliable information from a multitude of cues is largely unknown. We examined movement decisions of sea lampreys (Petromyzon marinus L.) exposed to a conspecific and an environmental cue during pre-spawning migration. Specifically, we predicted that the mature male-released sex pheromone 3-keto petromyzonol sulfate (3kPZS) will outweigh the locomotor inhibiting effects of cold stream temperature (less than 15°C). Using large-scale stream bioassays, we found that 3kPZS elicits an increase (more than 40%) in upstream movement of pre-spawning lampreys when the water temperatures were below 15°C. Both warming temperatures and conspecific cues increase upstream movement when the water temperature rose above 15°C. These patterns define an interaction between abiotic and conspecific cues in modulating animal decision-making, providing an example of the hierarchy of contradictory information.

  8. Social Modulation of Associative Fear Learning by Pheromone Communication

    Science.gov (United States)

    Bredy, Timothy W.; Barad, Mark

    2009-01-01

    Mice communicate through visual, vocal, and olfactory cues that influence innate, nonassociative behavior. We here report that exposure to a recently fear-conditioned familiar mouse impairs acquisition of conditioned fear and facilitates fear extinction, effects mimicked by both an olfactory chemosignal emitted by a recently fear-conditioned…

  9. The evolution of honest queen pheromones in insect societies

    DEFF Research Database (Denmark)

    van Zweden, Jelle Stijn

    2010-01-01

    Social insect workers are often capable of reproduction, but will not do so in the presence of a fertile queen. In large societies, queens are expected to produce a pheromone that honestly signals her dominance and/or fertility, to which workers respond by suppressing the development...... it is undermined by the fitness benefits of direct reproduction of workers at the individual level. A better explanation may be found in the idea that queen pheromones are difficult to produce for subordinate individuals, either because policing workers attack them, or because queen pheromones are intrinsically...

  10. Worker honey bee pheromone regulation of foraging ontogeny

    Science.gov (United States)

    Pankiw, Tanya

    The evolution of sociality has configured communication chemicals, called primer pheromones, which play key roles in regulating the organization of social life. Primer pheromones exert relatively slow effects that fundamentally alter developmental, physiological, and neural systems. Here, I demonstrate how substances extracted from the surface of foraging and young pre-foraging worker bees regulated age at onset of foraging, a developmental process. Hexane-extractable compounds washed from foraging workers increased foraging age compared with controls, whereas extracts of young pre-foraging workers decreased foraging age. This represents the first known direct demonstration of primer pheromone activity derived from adult worker bees.

  11. Pheromones and their role as aphrodisiacs:A review

    Institute of Scientific and Technical Information of China (English)

    Alok Semwal; Ratendra Kumar; Udai Vir Singh Teotia; Ramandeep Singh

    2013-01-01

    Since the beginning of the human existence on the earth reproductive biology remained a main concern of research because of its importance.It is widely recognized and demonstrated that odors play an important role in mammalian reproduction.A large number of studies have been carried out in humans, in order to investigate possible pheromones, their properties, mechanism of action, and possible receptors for their action.Till now scientific studies indicated that humans use olfactory communication and are even able to produce and perceive certain pheromones.This review article aims to highlight the role of human pheromones as aphrodisiacs.

  12. Pheromones and their role as aphrodisiacs: A review

    Directory of Open Access Journals (Sweden)

    Alok Semwal

    2013-01-01

    Full Text Available Since the beginning of the human existence on the earth reproductive biology remained a main concern of research because of its importance. It is widely recognized and demonstrated that odors play an important role in mammalian reproduction. A large number of studies have been carried out in humans, in order to investigate possible pheromones, their properties, mechanism of action, and possible receptors for their action. Till now scientific studies indicated that humans use olfactory communication and are even able to produce and perceive certain pheromones. This review article aims to highlight the role of human pheromones as aphrodisiacs

  13. Pheromone signaling during sexual reproduction in algae.

    Science.gov (United States)

    Frenkel, Johannes; Vyverman, Wim; Pohnert, Georg

    2014-08-01

    Algae are found in all aquatic and many terrestrial habitats. They are dominant in phytoplankton and biofilms thereby contributing massively to global primary production. Since algae comprise photosynthetic representatives of the various protoctist groups their physiology and appearance is highly diverse. This diversity is also mirrored in their characteristic life cycles that exhibit various facets of ploidy and duration of the asexual phase as well as gamete morphology. Nevertheless, sexual reproduction in unicellular and colonial algae usually has as common motive that two specialized, sexually compatible haploid gametes establish physical contact and fuse. To guarantee mating success, processes during sexual reproduction are highly synchronized and regulated. This review focuses on sex pheromones of algae that play a key role in these processes. Especially, the diversity of sexual strategies as well as of the compounds involved are the focus of this contribution. Discoveries connected to algal pheromone chemistry shed light on the role of key evolutionary processes, including endosymbiotic events and lateral gene transfer, speciation and adaptation at all phylogenetic levels. But progress in this field might also in the future provide valid tools for the manipulation of aquaculture and environmental processes.

  14. Acute behavioral responses to pheromones in C. elegans (adult behaviors: attraction, repulsion).

    Science.gov (United States)

    Jang, Heeun; Bargmann, Cornelia I

    2013-01-01

    The pheromone drop test is a simple and robust behavioral assay to quantify acute avoidance of pheromones in C. elegans, and the suppression of avoidance by attractive pheromones. In the pheromone drop test, water-soluble C. elegans pheromones are individually applied to animals that are freely moving on a large plate. Upon encountering a repellent, each C. elegans animal may or may not try to escape by making a long reversal. The fraction of animals that make a long reversal response indicates the repulsiveness of a given pheromone to a specific genotype/strain of C. elegans. Performing the drop test in the presence of bacterial food enhances the avoidance response to pheromones. Attraction to pheromones can be assayed by the suppression of reversals to repulsive pheromones or by the suppression of the basal reversal rate to buffer.

  15. Brood parasitism selects for no defence in a cuckoo host.

    Science.gov (United States)

    Krüger, Oliver

    2011-09-22

    In coevolutionary arms races, like between cuckoos and their hosts, it is easy to understand why the host is under selection favouring anti-parasitism behaviour, such as egg rejection, which can lead to parasites evolving remarkable adaptations to 'trick' their host, such as mimetic eggs. But what about cases where the cuckoo egg is not mimetic and where the host does not act against it? Classically, such apparently non-adaptive behaviour is put down to evolutionary lag: given enough time, egg mimicry and parasite avoidance strategies will evolve. An alternative is that absence of egg mimicry and of anti-parasite behaviour is stable. Such stability is at first sight highly paradoxical. I show, using both field and experimental data to parametrize a simulation model, that the absence of defence behaviour by Cape bulbuls (Pycnonotus capensis) against parasitic eggs of the Jacobin cuckoo (Clamator jacobinus) is optimal behaviour. The cuckoo has evolved massive eggs (double the size of bulbul eggs) with thick shells, making it very hard or impossible for the host to eject the cuckoo egg. The host could still avoid brood parasitism by nest desertion. However, higher predation and parasitism risks later in the season makes desertion more costly than accepting the cuckoo egg, a strategy aided by the fact that many cuckoo eggs are incorrectly timed, so do not hatch in time and hence do not reduce host fitness to zero. Selection will therefore prevent the continuation of any coevolutionary arms race. Non-mimetic eggs and absence of defence strategies against cuckoo eggs will be the stable, if at first sight paradoxical, result.

  16. Effects of experimental brood size manipulation and gender on carotenoid levels of Eurasian kestrels Falco tinnunculus.

    Directory of Open Access Journals (Sweden)

    Toni Laaksonen

    Full Text Available BACKGROUND: Animals use carotenoid-pigments for coloration, as antioxidants and as enhancers of the immune system. Carotenoid-dependent colours can thus signal individual quality and carotenoids have also been suggested to mediate life-history trade-offs. METHODOLOGY: To examine trade-offs in carotenoid allocation between parents and the young, or between skin coloration and plasma of the parents at different levels of brood demand, we manipulated brood sizes of Eurasian kestrels (Falco tinnunculus. PRINCIPAL FINDINGS: Brood size manipulation had no overall effect on plasma carotenoid levels or skin hue of parents, but female parents had twice the plasma carotenoid levels of males. Males work physically harder than females and they might thus also use more carotenoids against oxidative stress than females. Alternatively, females could be gaining back the carotenoid stores they depleted during egg-laying by eating primarily carotenoid-rich food items during the early nestling stage. Fledglings in enlarged broods had higher plasma carotenoid concentrations than those in reduced broods. This difference was not explained by diet. In light of recent evidence from other species, we suggest it might instead be due to fledglings in enlarged broods having higher testosterone levels, which in turn increased plasma carotenoid levels. The partial cross-foster design of our experiment revealed evidence for origin effects (genetic or maternal on carotenoid levels of fledglings, but no origin-environment interaction. SIGNIFICANCE: These results from wild birds differ from studies in captivity, and thus offer new insights into carotenoid physiology in relation to division of parental care and demands of the brood.

  17. Candidate pheromone receptors of codling moth Cydia pomonella respond to pheromones and kairomones.

    Science.gov (United States)

    Cattaneo, Alberto Maria; Gonzalez, Francisco; Bengtsson, Jonas M; Corey, Elizabeth A; Jacquin-Joly, Emmanuelle; Montagné, Nicolas; Salvagnin, Umberto; Walker, William B; Witzgall, Peter; Anfora, Gianfranco; Bobkov, Yuriy V

    2017-01-24

    Olfaction plays a dominant role in the mate-finding and host selection behaviours of the codling moth (Cydia pomonella), an important pest of apple, pear and walnut orchards worldwide. Antennal transcriptome analysis revealed a number of abundantly expressed genes related to the moth olfactory system, including those encoding the olfactory receptors (ORs) CpomOR1, CpomOR3 and CpomOR6a, which belong to the pheromone receptor (PR) lineage, and the co-receptor (CpomOrco). Using heterologous expression, in both Drosophila olfactory sensory neurones and in human embryonic kidney cells, together with electrophysiological recordings and calcium imaging, we characterize the basic physiological and pharmacological properties of these receptors and demonstrate that they form functional ionotropic receptor channels. Both the homomeric CpomOrco and heteromeric CpomOrco + OR complexes can be activated by the common Orco agonists VUAA1 and VUAA3, as well as inhibited by the common Orco antagonists amiloride derivatives. CpomOR3 responds to the plant volatile compound pear ester ethyl-(E,Z)-2,4-decadienoate, while CpomOR6a responds to the strong pheromone antagonist codlemone acetate (E,E)-8,10-dodecadien-1-yl acetate. These findings represent important breakthroughs in the deorphanization of codling moth pheromone receptors, as well as more broadly into insect ecology and evolution and, consequently, for the development of sustainable pest control strategies based on manipulating chemosensory communication.

  18. Candidate pheromone receptors of codling moth Cydia pomonella respond to pheromones and kairomones

    Science.gov (United States)

    Cattaneo, Alberto Maria; Gonzalez, Francisco; Bengtsson, Jonas M.; Corey, Elizabeth A.; Jacquin-Joly, Emmanuelle; Montagné, Nicolas; Salvagnin, Umberto; Walker, William B.; Witzgall, Peter; Anfora, Gianfranco; Bobkov, Yuriy V.

    2017-01-01

    Olfaction plays a dominant role in the mate-finding and host selection behaviours of the codling moth (Cydia pomonella), an important pest of apple, pear and walnut orchards worldwide. Antennal transcriptome analysis revealed a number of abundantly expressed genes related to the moth olfactory system, including those encoding the olfactory receptors (ORs) CpomOR1, CpomOR3 and CpomOR6a, which belong to the pheromone receptor (PR) lineage, and the co-receptor (CpomOrco). Using heterologous expression, in both Drosophila olfactory sensory neurones and in human embryonic kidney cells, together with electrophysiological recordings and calcium imaging, we characterize the basic physiological and pharmacological properties of these receptors and demonstrate that they form functional ionotropic receptor channels. Both the homomeric CpomOrco and heteromeric CpomOrco + OR complexes can be activated by the common Orco agonists VUAA1 and VUAA3, as well as inhibited by the common Orco antagonists amiloride derivatives. CpomOR3 responds to the plant volatile compound pear ester ethyl-(E,Z)-2,4-decadienoate, while CpomOR6a responds to the strong pheromone antagonist codlemone acetate (E,E)-8,10-dodecadien-1-yl acetate. These findings represent important breakthroughs in the deorphanization of codling moth pheromone receptors, as well as more broadly into insect ecology and evolution and, consequently, for the development of sustainable pest control strategies based on manipulating chemosensory communication. PMID:28117454

  19. Brooding Rumination and Internalizing Symptoms in Childhood: Investigating Symptom Specificity in a Multi-Wave Prospective Study

    OpenAIRE

    Lopez, Cristina M.; Felton, Julia W.; Driscoll, Kimberly A.; Kistner, Janet A.

    2012-01-01

    Specificity of brooding rumination as a cognitive vulnerability for anxiety and depression was examined using the tripartite theory as a framework. The three factors of the tripartite theory (negative affect, positive affect, and physiological hyperarousal) were included in the same structural equation model (latent growth curves) to test three competing hypotheses: brooding rumination as a depression-specific vulnerability (i.e., brooding uniquely predicts shared negative affect + specific p...

  20. New pheromone components of the grapevine moth Lobesia botrana.

    Science.gov (United States)

    Witzgall, Peter; Tasin, Marco; Buser, Hans-Ruedi; Wegner-Kiss, Gertrud; Mancebón, Vicente S Marco; Ioriatti, Claudio; Bäckman, Anna-Carin; Bengtsson, Marie; Lehmann, Lutz; Francke, Wittko

    2005-12-01

    Analysis of extracts of sex pheromone glands of grapevine moth females Lobesia botrana showed three previously unidentified compounds, (E)-7-dodecenyl acetate and the (E,E)- and (Z,E)-isomers of 7,9,11-dodecatrienyl acetate. This is the first account of a triply unsaturated pheromone component in a tortricid moth. The monoenic acetate (E)-7-dodecenyl acetate and the trienic acetate (7Z,9E,11)-dodecatrienyl acetate significantly enhanced responses of males to the main pheromone compound, (7E,9Z)-7,9-dodecadienyl acetate, in the wind tunnel. The identification of sex pheromone synergists in L. botrana may be of practical importance for the development of integrated pest management systems.

  1. Identification of the sex pheromone of Holotrichia reynaudi.

    Science.gov (United States)

    Ward, Andrew; Moore, Chris; Anitha, V; Wightman, John; Rogers, D John

    2002-03-01

    The male attractant pheromone of the scarab beetle Holotrichia reynaudi, an agricultural pest native to southern India, was extracted from abdominal glands of females with hexane and analyzed by gas chromatography-mass spectrometry. Field testing of the candidate chemicals, indole, phenol, and anisole, both alone and as binary mixtures, led us to conclude that anisole was the major component of the sex pheromone. Neither male nor female beetles were attracted to indole or phenol on their own. Similarly, when indole and anisole were combined, the attractiveness of the solution did not increase over that obtained with anisole alone. However, combination of phenol and anisole did alter the attractiveness of anisole, with fewer male beetles attracted to the binary mixture than to anisole on its own. The behavior of female beetles was not altered by any of the chemicals tested. Anisole is also the sex pheromone of H. consanguinea, making this the first known example of two melolonthine scarabs sharing the same pheromone.

  2. The evolution of queen pheromones in the ant genus Lasius.

    Science.gov (United States)

    Holman, L; Lanfear, R; d'Ettorre, P

    2013-07-01

    Queen pheromones are among the most important chemical messages regulating insect societies yet they remain largely undiscovered, hindering research into interesting proximate and ultimate questions. Identifying queen pheromones in multiple species would give new insight into the selective pressures and evolutionary constraints acting on these ubiquitous signals. Here, we present experimental and comparative evidence that 3-methylalkanes, hydrocarbons present on the queen's cuticle, are a queen pheromone throughout the ant genus Lasius. Interspecific variation in the chemical profile is consistent with 3-methylalkanes evolving more slowly than other types of hydrocarbons, perhaps due to differential selection or evolutionary constraints. We argue that the sensory ecology of the worker response imposes strong stabilizing selection on queen pheromones relative to other hydrocarbons. 3-Methylalkanes are also strongly physiologically and genetically coupled with fecundity in at least one Lasius species, which may translate into evolutionary constraints. Our results highlight how honest signalling could minimize evolutionary conflict over reproduction, promoting the evolution and maintenance of eusociality.

  3. Directional Bias and Pheromone for Discovery and Coverage on Networks

    Energy Technology Data Exchange (ETDEWEB)

    Fink, Glenn A.; Berenhaut, Kenneth S.; Oehmen, Christopher S.

    2012-09-11

    Natural multi-agent systems often rely on “correlated random walks” (random walks that are biased toward a current heading) to distribute their agents over a space (e.g., for foraging, search, etc.). Our contribution involves creation of a new movement and pheromone model that applies the concept of heading bias in random walks to a multi-agent, digital-ants system designed for cyber-security monitoring. We examine the relative performance effects of both pheromone and heading bias on speed of discovery of a target and search-area coverage in a two-dimensional network layout. We found that heading bias was unexpectedly helpful in reducing search time and that it was more influential than pheromone for improving coverage. We conclude that while pheromone is very important for rapid discovery, heading bias can also greatly improve both performance metrics.

  4. Pheromone Chemistry of the Smaller European Elm Bark Beetle.

    Science.gov (United States)

    Beck, Keith

    1978-01-01

    Discusses the aggregation pheromone of the smaller European elm bark beetle, Scolytus multistriatus (Marsham), with emphasis on information that could be used in the classroom as a practical application of organic chemistry. (Author/GA)

  5. Pheromonal contest between honeybee workers ( Apis mellifera capensis)

    Science.gov (United States)

    Moritz, R. F. A.; Simon, U. E.; Crewe, R. M.

    2000-10-01

    Queenless workers of the Cape honeybee ( Apis mellifera capensis) can develop into reproductives termed pseudoqueens. Although they morphologically remain workers they become physiologically queenlike, produce offspring, and secrete mandibular gland pheromones similar to those of true queens. However, after queen loss only very few workers gain pseudoqueen status. A strong intracolonial selection governs which workers start oviposition and which remain sterile. The "queen substance", 9-keto-2(E)-decenoic acid (9-ODA), the dominant compound of the queen's mandibular gland pheromones, suppresses the secretion of queenlike mandibular gland pheromones in workers. It may act as an important signal in pseudoqueen selection. By analysing the mandibular gland pheromones of workers kept in pairs, we found that A. m. capensis workers compete to produce the strongest queen-like signal.

  6. The role of pheromones and biostimulation in animal reproduction.

    Science.gov (United States)

    Rekwot, P I; Ogwu, D; Oyedipe, E O; Sekoni, V O

    2001-03-30

    It is now known that pheromonal communication plays an important role in mammalian behaviour and reproductive processes. Chemical communication with pheromones is one means of transmitting such information. In mammals, signalling and priming pheromones are thought to act either singly or in combination through olfaction, auditory, visual (sight) or tactile stimuli. Pheromones are air-borne chemical substances ("signals") released in the urine or feces of animals or secreted from cutaneous glands that are perceived by the olfactory system and that elicit both behavioural and endocrine responses in conspecifics. Extensive studies in insects, rodents, swine, sheep, goats and cattle have established the importance of pheromones in the strong influence exerted by the male on reproductive activity in the female. There is a pheromone produced by the queen honey bee, which has two functions: inhibition of queen rearing and suppression of oogenesis in workers and in addition attracts drones during nuptial flight. It has also been demonstrated that the urine of male mice, rats, feral species and other wild rodents contains a priming pheromone that is responsible for hastening puberty in the females. Pheromones in the wool, wax and urine of a ram are sufficient to stimulate ewes to ovulate, while the buck has a strong characteristic seasonal odor and a buck jar containing the odor of the buck can be used as an aid in the detection of oestrus in does. The mere presence of the boar at the time of insemination of the sow improves sperm transport and ovulation, while the presence of the vasectomised bull has been reported to hasten the onset of puberty in heifers and also early resumption of ovarian activity in cattle following parturition. The role of pheromones in bovine reproduction is not as clearly defined as in sheep, goats and swine. Pheromones and other allelomimetic cues can exert profound effects on reproductive activity via the hypothalamic system that generates pulses

  7. The Active Space of Mexican Rice Borer Pheromone Traps.

    Science.gov (United States)

    Wilson, Blake E; Beuzelin, Julien M; Allison, Jeremy D; Reagan, Thomas E

    2016-09-01

    The Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), is an invasive pest of sugarcane, Saccharum spp., rice, Oryza sativa L., and other graminaceous crops in the United States. Traps baited with the synthetic female sex pheromone of E. loftini are used for monitoring and management of this invasive pest. However, the active space, or radius of attraction, of these traps is not known. Two field experiments examined the effect of intertrap distance on trap captures with hexagonal arrays of traps deployed in rice stubble habitat in Texas (2011) and Louisiana (2013). Trap capture increased with increasing intertrap distance. Trap interference occurred at intertrap distances ≤50 m in the 2011 experiment. Results from the experiment conducted in 2013 indicate that trap interference occurs at intertrap distances of 50 m, but not at distances ≥100 m. These results suggest that under field conditions, E. loftini pheromone traps attract males from distances of 50-100 m. The active space of pheromone traps also was examined under controlled wind conditions by direct observation of male response to detection of the female sex pheromone. Eoreuma loftini males responded to the pheromone blend by becoming active, fanning their wings, and rapidly walking in circles. The mean distance from the pheromone source at which males responded was 47.6 m. This work provides the first documentation of active space for traps baited with female sex pheromone for a crambid species, and these data will improve pheromone trap deployment strategies for E. loftini monitoring and management.

  8. Brood reduction via intra-clutch variation in testosterone--an experimental test in the great tit.

    Directory of Open Access Journals (Sweden)

    Katarzyna Podlas

    Full Text Available In birds, yolk androgen concentrations in eggs can increase or decrease over the laying sequence and common hypotheses hold that this serves to favour the competitive ability of either first- or last-hatched chicks depending on the prevailing conditions, and thus promote brood reduction or maintenance of original brood size respectively. Intra-clutch variation of testosterone can shift relative competitive ability of siblings and hence competitive dynamics. In a natural population of great tits, we experimentally investigated the effects and function of maternal testosterone on offspring phenotype in relation to the laying position of the egg in a context of hatching asynchrony. To this end, we created three types of clutches where either the first three or the last three eggs of a clutch were injected with testosterone (T dissolved in sesame oil, and the remaining eggs with sesame oil only, or where all eggs of a clutch were injected with sesame oil. Increased levels of yolk T in the last-laid eggs resulted in the last-hatched chicks being significantly lighter and smaller than their siblings, while increased levels of T in the first-laid eggs had no direct effect on the first-hatched chicks, but an indirect negative effect on their siblings. Our results suggest that females can potentially adjust offspring phenotype by modulating, over the laying sequence, the amounts of T deposited in the eggs. These results are in contradiction, however, with current hypotheses and previous findings, which suggest that under good conditions higher levels of maternally derived T in the last-laid eggs should mitigate the negative effects of hatching asynchrony.

  9. Pheromones of milkweed bugs (Heteroptera: Lygaeidae) attract wayward plant bugs: Phytocoris mirid sex pheromone.

    Science.gov (United States)

    Zhang, Qing-He; Aldrich, Jeffrey R

    2003-08-01

    The synthetic aggregation pheromone of the large milkweed bug, Oncopeltus fasciatus (Dallas) (Lygaeinae), also attracted males of the plant bug, Phytocoris difficilis Knight (Miridae). Field testing partial blends against the six-component blend comprising the Oncopeltus pheromone showed that cross-attraction of P. difficilis males was due to synergism between (E)-2-octenyl acetate and (E,E)-2,4-hexadienyl acetate. Hexyl acetate was abundant in the metathoracic scent gland (MSG) secretion of P. difficilis males, but because female P. difficilis could not initially be found in the field, further combinatorial tests were guided by prior research on the pheromones of two Phytocoris species in the western United States. The combination of hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates was as attractive to P. difficilis males as the milkweed bug pheromone, yet no milkweed bugs were drawn to this blend. Gas chromatographic (GC)-electroantennographic detection (EAD) and GC-mass spectrometric (MS) analyses of female P. difficilis MSGs determined that their secretion contained predominantly hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates (all strongly EAD-active)-the latter two compounds found only in trace amounts from males-plus five minor female-specific compounds, three of which were EAD-active. (E,E)-2,4-Hexadienyl acetate was not detected from P. difficilis females or males. The blend of the three major components, hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates (2:1.5:1 by volume), was as attractive as the blend of all six EAD-active compounds identified from females, indicating that this ternary blend constitutes the sex pheromone of P. difficilis. Hexyl acetate with (E)-2-octenyl acetate also attracted males of another species, P. breviusculus Reuter, but addition of (E)-2-hexenyl acetate and/or (E,E)-2,4-hexadienyl acetate inhibited attraction of P. breviusculus males. Attraction of P. difficilis males occurred mainly during the first half of scotophase. The

  10. Phenotypic plasticity in sex pheromone production in Bicyclus anynana butterflies.

    Science.gov (United States)

    Dion, Emilie; Monteiro, Antónia; Yew, Joanne Y

    2016-12-14

    Phenotypic plasticity refers to the environmental control of phenotypes. Cues experienced during development (developmental plasticity) or during adulthood (acclimatization) can both affect adult phenotypes. Phenotypic plasticity has been described in many traits but examples of developmental plasticity in physiological traits, in particular, remain scarce. We examined developmental plasticity and acclimatization in pheromone production in the butterfly Bicyclus anynana in response to rearing temperature. B. anynana lives in the African tropics where warm rearing temperatures of the wet season produce active males that court and females that choose, whereas cooler temperatures of the dry season lead to choosy less active males and courting females. We hypothesized that if male pheromone production is costly, it should be reduced in the dry season form. After describing the ultrastructure of pheromone producing cells, we showed that dry season males produced significantly less sex pheromones than wet season males, partly due to acclimatization and partly due to developmental plasticity. Variation in levels of one of the compounds is associated with differential regulation of a pheromone biosynthetic enzyme gene. This plasticity might be an adaptation to minimize pheromone production costs during the stressful dry season.

  11. Cooperation, conflict, and the evolution of queen pheromones.

    Science.gov (United States)

    Kocher, Sarah D; Grozinger, Christina M

    2011-11-01

    While chemical communication regulates individual behavior in a wide variety of species, these communication systems are most elaborated in insect societies. In these complex systems, pheromones produced by the reproductive individuals (queens) are critical in establishing and maintaining dominant reproductive status over hundreds to thousands of workers. The proximate and ultimate mechanisms by which these intricate pheromone communication systems evolved are largely unknown, though there has been much debate over whether queen pheromones function as a control mechanism or as an honest signal facilitating cooperation. Here, we summarize results from recent studies in honey bees, bumble bees, wasps, ants and termites. We further discuss evolutionary mechanisms by which queen pheromone communication systems may have evolved. Overall, these studies suggest that queen-worker pheromone communication is a multi-component, labile dialog between the castes, rather than a simple, fixed signal-response system. We also discuss future approaches that can shed light on the proximate and ultimate mechanisms that underlie these complex systems by focusing on the development of increasingly sophisticated genomic tools and their potential applications to examine the molecular mechanisms that regulate pheromone production and perception.

  12. Trail Pheromone Disruption of Argentine Ant Trail Formation and Foraging

    Science.gov (United States)

    Suckling, D.M.; Peck, R.W.; Stringer, L.D.; Snook, K.; Banko, P.C.

    2010-01-01

    Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2-3 m s-1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. ?? Springer Science+Business Media, LLC 2010.

  13. Pheromones and their effect on women's mood and sexuality.

    Science.gov (United States)

    Verhaeghe, J; Gheysen, R; Enzlin, P

    2013-01-01

    Pheromones are substances which are secreted to the outside by an individual and received by a second individual of the same species. Many examples exist in animals but their role in humans remains uncertain since adults have no functioning vomeronasal organ, which processes pheromone signals in animals. Yet pheromones can be detected by the olfactory system although humans under develop and underrate their smelling sense. Pheromones may be present in all bodily secretions but most attention has been geared toward axillary sweat which contains the odorous 16-androstenes. One of these steroidal compounds, androstadienone, is present at much higher concentrations in male sweat and can be detected by women, albeit with wide variation in sensitivity. Upper-lip application of a pharmacological dose of androstadienonein women results in improved mood and heightened focus - particularly to capture emotional information. A positive mood is known to facilitate women's sexual response, and -increased focus improves sexual satisfaction. Indeed, some studies showed a beneficial effect of androstadienone on sexual desire and arousal. However, these effects were dependent on the context of the experiment, for example, on the presence of a male attendant. Pheromones may also play a role in mate selection which is "disassortative" regarding the human leukocyte antigen (HLA)-genotype. Preliminary evidence suggests that exposure to androstadienone in women promotes attractiveness ratings of potential mates. In conclusion, some data indicate that 16-androstene pheromones, in particular androstadienone, play a beneficial role in women's mood, focus and sexual response, and perhaps also in mate selection.

  14. Field capture of Thyanta perditor with pheromone-baited traps

    Directory of Open Access Journals (Sweden)

    Raúl Alberto Laumann

    2011-02-01

    Full Text Available The objective of this work was to evaluate the field attractiveness of Thyanta perditor synthetic sex pheromone-baited traps, its attractivity to other stink bug species, and the response of T. perditor to a geometric isomer of the sex pheromone. Two-liter transparent plastic bottles traps were baited with rubber septa impregnated with the treatments: 1 mg of methyl-(2E,4Z,6Z-decatrienoate [(2E,4Z,6Z-10:COOMe], the male sex pheromone of T. perditor; 1 mg of (2E,4Z,6Z-10:COOMe protected from sunlight in standard PVC plumbing pipe; 1 mg of its geometric isomer [(2E,4E,6Z-10:COOMe]; and traps with rubber septa impregnated with hexane (control. The experiment was carried out in field during the soybean reproductive stages. Traps were monitored weekly, and the captures were compared to the population density estimated by the sampling cloth and visual inspection monitoring techniques. Traps baited with the sex pheromone, protected or not, were more effective in capturing T. perditor than traps baited with the isomer or the hexane. Thyanta perditor sex pheromone showed cross-attraction to other stink bug species, such as Euschistus heros, Edessa meditabunda, Piezodorus guildinii and Nezara viridula. Pheromone-baited traps can be used in population monitoring and to identify the relative composition of stink bug guilds.

  15. Species richness and distributions of boreal waterbirds in relation to nesting and brood-rearing habitats

    Science.gov (United States)

    Lewis, Tyler L.; Lindberg, Mark S.; Schmutz, Joel A.; Bertram, Mark R.; Dubour, Adam J.

    2015-01-01

    Identification of ecological factors that drive animal distributions allows us to understand why distributions vary temporally and spatially, and to develop models to predict future changes to populations–vital tools for effective wildlife management and conservation. For waterbird broods in the boreal forest, distributions are likely driven by factors affecting quality of nesting and brood-rearing habitats, and the influence of these factors may extend beyond singles species, affecting the entire waterbird community. We used occupancy models to assess factors influencing species richness of waterbird broods on 72 boreal lakes, along with brood distributions of 3 species of conservation concern: lesser scaup (Aythya affinis), white-winged scoters (Melanitta fusca), and horned grebe (Podiceps auritus). Factors examined included abundance of invertebrate foods (Amphipoda, Diptera, Gastropoda, Hemiptera, Odonata), physical lake attributes (lake area, emergent vegetation), water chemistry (nitrogen, phosphorus, chlorophyll a concentrations), and nesting habitats (water edge, non-forest cover). Of the 5 invertebrates, only amphipod density was related to richness and occupancy, consistently having a large and positive relationship. Despite this importance to waterbirds, amphipods were the most patchily distributed invertebrate, with 17% of the study lakes containing 70% of collected amphipods. Lake area was the only other covariate that strongly and positively influenced species richness and occupancy of scaup, scoters, and grebes. All 3 water chemistry covariates, which provided alternative measures of lake productivity, were positively related to species richness but had little effect on scaup, scoter, and grebe occupancy. Conversely, emergent vegetation was negatively related to richness, reflecting avoidance of overgrown lakes by broods. Finally, nesting habitats had no influence on richness and occupancy, indicating that, at a broad spatial scale, brood

  16. [Pheromones: an underestimated communication signal in humans].

    Science.gov (United States)

    Frey, J

    2003-01-01

    The pheromones are molecules, mainly aliphatic acids, with or without perceptible odor, recognized by specific receptors, the stimulation of which induces neuroendocrine reactions and affects the individual behavior. Olfactory receptors are underexpressed in human, 70 % of genes have become nonfunctional pseudogenes. But the remaining function was tested and is able to induce emotional reactions corresponding to a non-verbal signal of social interactions. In the present study, we review the actual knowledge on the olfactory receptors. They belong to the G-protein-coupled-receptors. Their signal is transduced to the hypothalamic-pituitary-gonadal axis. Some HLA-based olfactory cues are shown with reference to recent experiments. The pathophysiological hypotheses are considered with respect to studies in anorexia nervosa and Alzheimer' disease.

  17. If I only knew why: the relationship between brooding, beliefs about rumination, and perceptions of treatments.

    Science.gov (United States)

    Ophir, Yaakov; Mor, Nilly

    2014-07-01

    People who tend to engage in brooding, the maladaptive subtype of rumination, are at risk to develop depression. Brooders often endorse metacognitive beliefs that self-focused ruminative thinking is beneficial. In the current study, we examined whether brooding and positive beliefs about rumination are associated with perceptions of and preferences for treatments for depression. Participants (N=118) read descriptions of two different clusters of treatments for depression, Insight-Oriented (IO) treatments and Activation-Oriented (AO) treatments. They then rated treatment efficacy and credibility and completed self-report measures of rumination (including brooding and reflection subscales), beliefs about rumination, and depression. Brooding and metacognitive positive beliefs about rumination were associated with positive perceptions of IO (but not AO) treatments. Positive beliefs about rumination contributed to the prediction of perceptions of IO treatments (but not AO treatments) beyond the effect of brooding. We discuss the implications of these findings for individuals' decision-making processes regarding which type of treatment to seek.

  18. Physiological responses to increased brood size and ectoparasite infestation: Adult great tits favour self-maintenance.

    Science.gov (United States)

    Wegmann, Michele; Voegeli, Beatrice; Richner, Heinz

    2015-03-15

    Different types of stressors trigger responses of different physiological systems, and these responses may contribute differentially to the maintenance of homeostasis, to trade-offs and the evolution of life-history traits. To manipulate two common stressors during reproduction, we infested half of the nests in a naturally breeding great tit population with ectoparasites and simultaneously manipulated brood size, using a 2×2 experimental design. Parents in this model species commonly compensate for ectoparasites by an increase in food provisioning. We assessed parental responses to these concurrent stressors by measuring several physiological stress parameters such as changes in metabolic rate, oxidative stress and expression of heat-shock proteins (Hsp), and explored how these stressors affect the trade-off between self-maintenance and reproduction. Neither flea infestation nor brood size manipulation affected adult metabolic rate, oxidative damage or Hsp levels. Furthermore, we found no interactive effect of the two treatments on adults. However, nestlings in infested nests had lower body mass and lower survival. Nestlings in enlarged broods were lighter and had lower survival, although parents of enlarged broods increased food provisioning rate. The findings suggest that adults favour maintenance of cellular homeostasis, and physiological equilibrium over current reproduction, and that the costs induced by both stressors, flea infestation and increased brood size, are carried by the offspring. It emphasizes the importance of self-maintenance over reproduction in life-history decisions, and more generally the need of including physiological traits for understanding the evolution of life-histories.

  19. Ecological and physiological factors affecting brood patch area and prolactin levels in arctic-nesting geese

    Science.gov (United States)

    Jonsson, J.E.; Afton, A.D.; Alisauskas, R.T.; Bluhm, C.K.; El Halawani, M.E.

    2006-01-01

    We investigated effects of ecological and physiological factors on brood patch area and prolactin levels in free-ranging Lesser Snow Geese (Chen caerulescens caerulescens; hereafter "Snow Geese") and Ross's Geese (C. rossii). On the basis of the body-size hypothesis, we predicted that the relationships between prolactin levels, brood patch area, and body condition would be stronger in Ross's Geese than in the larger Snow Geese. We found that brood patch area was positively related to clutch volume and inversely related to prolactin levels in Ross's Geese, but not in Snow Geese. Nest size, nest habitat, and first egg date did not affect brood patch area in either species. Prolactin levels increased as incubation progressed in female Snow Geese, but this relationship was not significant in Ross's Geese. Prolactin levels and body condition (as indexed by size-adjusted body mass) were inversely related in Ross's Geese, but not in Snow Geese. Our findings are consistent with the prediction that relationships between prolactin levels, brood patch area, and body condition are relatively stronger in Ross's Geese, because they mobilize endogenous reserves at faster rates than Snow Geese. ?? The American Ornithologists' Union, 2006. Printed in USA.

  20. The Yeast ATF1 Acetyltransferase Efficiently Acetylates Insect Pheromone Alcohols: Implications for the Biological Production of Moth Pheromones.

    Science.gov (United States)

    Ding, Bao-Jian; Lager, Ida; Bansal, Sunil; Durrett, Timothy P; Stymne, Sten; Löfstedt, Christer

    2016-04-01

    Many moth pheromones are composed of mixtures of acetates of long-chain (≥10 carbon) fatty alcohols. Moth pheromone precursors such as fatty acids and fatty alcohols can be produced in yeast by the heterologous expression of genes involved in insect pheromone production. Acetyltransferases that subsequently catalyze the formation of acetates by transfer of the acetate unit from acetyl-CoA to a fatty alcohol have been postulated in pheromone biosynthesis. However, so far no fatty alcohol acetyltransferases responsible for the production of straight chain alkyl acetate pheromone components in insects have been identified. In search for a non-insect acetyltransferase alternative, we expressed a plant-derived diacylglycerol acetyltransferase (EaDAcT) (EC 2.3.1.20) cloned from the seed of the burning bush (Euonymus alatus) in a yeast system. EaDAcT transformed various fatty alcohol insect pheromone precursors into acetates but we also found high background acetylation activities. Only one enzyme in yeast was shown to be responsible for the majority of that background activity, the acetyltransferase ATF1 (EC 2.3.1.84). We further investigated the usefulness of ATF1 for the conversion of moth pheromone alcohols into acetates in comparison with Ea DAcT. Overexpression of ATF1 revealed that it was capable of acetylating these fatty alcohols with chain lengths from 10 to 18 carbons with up to 27- and 10-fold higher in vivo and in vitro efficiency, respectively, compared to Ea DAcT. The ATF1 enzyme thus has the potential to serve as the missing enzyme in the reconstruction of the biosynthetic pathway of insect acetate pheromones from precursor fatty acids in yeast.

  1. Conditional deletion of ERK5 MAP kinase in the nervous system impairs pheromone information processing and pheromone-evoked behaviors.

    Directory of Open Access Journals (Sweden)

    Junhui Zou

    Full Text Available ERK5 MAP kinase is highly expressed in the developing nervous system but absent in most regions of the adult brain. It has been implicated in regulating the development of the main olfactory bulb and in odor discrimination. However, whether it plays an essential role in pheromone-based behavior has not been established. Here we report that conditional deletion of the Mapk7 gene which encodes ERK5 in mice in neural stem cells impairs several pheromone-mediated behaviors including aggression and mating in male mice. These deficits were not caused by a reduction in the level of testosterone, by physical immobility, by heightened fear or anxiety, or by depression. Using mouse urine as a natural pheromone-containing solution, we provide evidence that the behavior impairment was associated with defects in the detection of closely related pheromones as well as with changes in their innate preference for pheromones related to sexual and reproductive activities. We conclude that expression of ERK5 during development is critical for pheromone response and associated animal behavior in adult mice.

  2. Brood care in a 100-million-year-old scale insect.

    Science.gov (United States)

    Wang, Bo; Xia, Fangyuan; Wappler, Torsten; Simon, Ewa; Zhang, Haichun; Jarzembowski, Edmund A; Szwedo, Jacek

    2015-01-01

    Behavior of extinct organisms can be inferred only indirectly, but occasionally rare fossils document particular behaviors directly. Brood care, a remarkable behavior promoting the survival of the next generation, has evolved independently numerous times among animals including insects. However, fossil evidence of such a complex behavior is exceptionally scarce. Here, we report an ensign scale insect (Hemiptera: Ortheziidae), Wathondara kotejai gen. et sp. nov., from mid-Cretaceous Burmese amber, which preserves eggs within a wax ovisac, and several freshly hatched nymphs. The new fossil is the only Mesozoic record of an adult female scale insect. More importantly, our finding represents the earliest unequivocal direct evidence of brood care in the insect fossil record and demonstrates a remarkably conserved egg-brooding reproductive strategy within scale insects in stasis for nearly 100 million years.

  3. Effects of brood parasitism by brown-headed cowbirds may persist in the post fledging period

    Science.gov (United States)

    Peterson, Sean M.; Streby, Henry M.; Andersen, David E.

    2012-01-01

    Brood parasitism by Brown-headed Cowbirds (Molothrus ater) typically decreases the number of host juveniles that fledge: however, little information exists regarding the effect of cowbird parasitism during the post-fledging period. We monitored 115 Ovenbird (Seiurus aurocapilla) nests in 2006–2008 in northcentral Minnesota, six of which were parasitized. We used radiotelemetry to monitor movements of 36 Ovenbird fledglings (nine additional fledglings depredated 50 m from its nest and 25 days to travel >100 m from its nest. Fledglings from non-parasitized broods tracked for ≥25 days during 2008 (n  =  16) took 4.1 ± 0.71 and 9.5 ± 1.14 days to travel the same distances. Our observations suggest that negative effects of brood parasitism may persist into the post-fledging period, possibly confirming observations of cowbird-only survival compiled from the literature.

  4. [Symptomatic Black Queen Cell Virus infection of drone brood in Hessian apiaries].

    Science.gov (United States)

    Siede, Reinhold; Büchler, Ralph

    2003-01-01

    The Black Queen Cell Virus (BQCV) can affect brood of the honey bee (Apis mellifera). In general queen cells are endangered showing dark coloured cell walls as typical symptoms. Worker- and dronebrood can be infected by BQCV but normally without clinical symptoms. This paper describes for the first time a symptomatic BQCV-infection of diseased drone brood found on two bee yards in Hessen/Germany in 2001. The drone larvae were seriously damaged and some of them were dead. Samples of the affected brood were tested for BQCV by the PCR detection method. A BQCV specific nucleic acid fragment was found. The PCR product were sequenced and aligned with the relevant GenBank entry. At the nucleic acid level as well as at the deduced protein level the isolate showed a high similarity with the south african isolate noted in GenBank.

  5. Self-evaluative and emotion processes linked with brooding rumination among adolescents.

    Science.gov (United States)

    Burwell, Rebecca A

    2015-06-01

    Rumination has been linked with a number of deleterious outcomes, though relatively little is known about self-evaluative and emotion processes by which it develops. The current investigation uses a prospective, longitudinal design and self-report measures to examine the role of contingent self-worth, perfectionism, negative emotion beliefs, and suppression of negative emotion in predicting the development of brooding and reflective forms of rumination among 168 adolescents (98 girls, 79.6% European-American) undergoing the transition to high school (Mage = 13.58). Results of structural equation modeling indicate that self-evaluative vulnerability (i.e., self-worth contingencies, perfectionism) and negative emotion beliefs, but not the suppression of negative emotion, predict brooding (but not reflective) rumination. The current study demonstrates how brooding is intertwined with views of self and core assumptions about emotion.

  6. Fish embryo and juvenile size under hypoxia in the mouth- brooding African cichlid Pseudocrenilabrus multicolor

    Directory of Open Access Journals (Sweden)

    E.E. REARDON, L.J. CHAPMAN

    2012-06-01

    Full Text Available We used a field survey and a laboratory rearing experiment to (a examine response (size and survival to life-long hypoxia in offspring of the African maternal mouth-brooding cichlid Pseudocrenilabrus multicolor victoriae (Seegers and (b explore the degree to which developmental response can be environmentally-induced. Embryo size metrics were quantified in 9 field populations across a range of dissolved oxygen (DO concentrations. In the laboratory, first generation (F1 broods of low-DO origin were reared under high or low DO. Brooding period was quantified for the mothers; and egg size, egg metabolic rate and juvenile size-at-release were quantified in their (F2 offspring. The F2 offspring were split and grown for 3 months post-release under high or low DO, and juvenile size and survival were quantified. In the field survey, across stages, embryos from low-DO field populations were shorter and weighed less than embryos from high-DO populations. In the laboratory experiment, F2 eggs and juveniles-at-release from mother’s mouth did not differ in mass, length, survival regardless of development DO environment. However, juveniles diverged in size after leaving mother’s mouth, exhibiting smaller size when grown under low DO. Size differences in embryo size across field populations and divergence in embryo size after release from the mother’s mouth support predictions for smaller body size under hypoxia. There was no evidence for negative effects on survival of juveniles after 3 months. Brooding period was 16% shorter in females reared under low DO suggesting that hypoxia may accelerate embryo development. This work provides insights into how bearer fishes respond to hypoxic stress relative to fishes with no post-spawning parental care; a shorter brooding interval and smaller body size may provide an optimal solution to parent and embryo survival under hypoxia in brooding fishes [Current Zoology 58 (3: 401-412, 2012].

  7. Fish embryo and juvenile size under hypoxia in the mouth-brooding African cichlid Pseudocrenilabrus multicolor

    Institute of Scientific and Technical Information of China (English)

    E.E.REARDON; L.J.CHAPMAN

    2012-01-01

    We used a field survey and a laboratory rearing experiment to (a) examine response (size and survival) to life-long hypoxia in offspring of the African maternal mouth-brooding cichlid Pseudocrenilabrus multicolor victoriae (Seegers) and (b) explore the degree to which developmental response can be environmentally-induced.Embryo size metrics were quantified in 9 field populations across a range of dissolved oxygen (DO) concentrations.In the laboratory,first generation (F1) broods of low-DO origin were reared under high or low DO.Brooding period was quantified for the mothers; and egg size,egg metabolic rate and juvenile size-at-release were quantified in their (F2) offspring.The F2 offspring were split and grown for 3 months post-release under high or low DO,and juvenile size and survival were quantified.In the field survey,across stages,embryos from low-DO field populations were shorter and weighed less than embryos from high-DO populations.In the laboratory experiment,F2 eggs and juveniles-at-release from mother's mouth did not differ in mass,length,survival regardless of development DO environment.However,juveniles diverged in size after leaving mother's mouth,exhibiting smaller size when grown under low DO.Size differences in embryo size across field populations and divergence in embryo size after release from the mother's mouthsupport predictions for smaller body size under hypoxia.There was no evidence for negative effects on survival of juveniles after 3 months.Brooding period was 16% shorter in females reared under low DO suggesting that hypoxia may accelerate embryo development.This work provides insights into how bearer fishes respond to hypoxic stress relative to fishes with no post-spawning parental care; a shorter brooding interval and smaller body size may provide an optimal solution to parent and embryo survival under hypoxia in brooding fishes.

  8. Pheromones and their effect on women’s mood and sexuality

    OpenAIRE

    2013-01-01

    Pheromones are substances which are secreted to the outside by an individual and received by a second individual of the same species. Many examples exist in animals but their role in humans remains uncertain since adults have no functioning vomeronasal organ, which processes pheromone signals in animals. Yet pheromones can be detected by the olfactory system although humans under develop and underrate their smelling sense. Pheromones may be present in all bodily secretions but most attention ...

  9. Temperature limits trail following behaviour through pheromone decay in ants

    Science.gov (United States)

    van Oudenhove, Louise; Billoir, Elise; Boulay, Raphaël; Bernstein, Carlos; Cerdá, Xim

    2011-12-01

    In Mediterranean habitats, temperature affects both ant foraging behaviour and community structure. Many studies have shown that dominant species often forage at lower temperature than subordinates. Yet, the factors that constrain dominant species foraging activity in hot environments are still elusive. We used the dominant ant Tapinoma nigerrimum as a model species to test the hypothesis that high temperatures hinder trail following behaviour by accelerating pheromone degradation. First, field observations showed that high temperatures (> 30°C) reduce the foraging activity of T. nigerrimum independently of the daily and seasonal rhythms of this species. Second, we isolated the effect of high temperatures on pheromone trail efficacy from its effect on worker physiology. A marked substrate was heated during 10 min (five temperature treatments from 25°C to 60°C), cooled down to 25°C, and offered in a test choice to workers. At hot temperature treatments (>40°C), workers did not discriminate the previously marked substrate. High temperatures appeared therefore to accelerate pheromone degradation. Third, we assessed the pheromone decay dynamics by a mechanistic model fitted with Bayesian inference. The model predicted ant choice through the evolution of pheromone concentration on trails as a function of both temperature and time since pheromone deposition. Overall, our results highlighted that the effect of high temperatures on recruitment intensity was partly due to pheromone evaporation. In the Mediterranean ant communities, this might affect dominant species relying on chemical recruitment, more than subordinate ant species, less dependent on chemical communication and less sensitive to high temperatures.

  10. First record of invasive Burmese Python oviposition and brooding inside an anthropogenic structure

    Science.gov (United States)

    Hanslowe, Emma; Falk, Bryan; Collier, Michelle A. M.; Josimovich, Jillian; Rahill, Thomas; Reed, Robert

    2016-01-01

    We discovered an adult female Python bivittatus (Burmese Python) coiled around a clutch of 25 eggs in a cement culvert in Flamingo, FL, in Everglades National Park. To our knowledge, this is the first record of an invasive Burmese Python laying eggs and brooding inside an anthropogenic structure in Florida. A 92% hatch-success rate suggests that the cement culvert provided suitable conditions for oviposition, embryonic development, and hatching. Given the plenitude of such anthropogenic structures across the landscape, available sites for oviposition and brooding may not be limiting for the invasive Burmese Python population.

  11. Stingless bees (Melipona subnitida) adjust brood production rather than foraging activity in response to changes in pollen stores.

    Science.gov (United States)

    Maia-Silva, Camila; Hrncir, Michael; Imperatriz-Fonseca, Vera Lucia; Schorkopf, Dirk Louis P

    2016-10-01

    Highly eusocial bees (honey bees and stingless bees) sustain their colonies through periods of resource scarcity by food stored within the nest. The protein supply necessary for successful brood production is ensured through adjustments of the colonies' pollen foraging according to the availability of this resource in the environment. In honey bees Apis mellifera, in addition, pollen foraging is regulated through the broods' demand for this resource. Here, we investigated the influence of the colony's pollen store level on pollen foraging and brood production in stingless bees (Melipona subnitida). When pollen was added to the nests, colonies increased their brood production and reduced their pollen foraging within 24 h. On the other hand, when pollen reserves were removed, colonies significantly reduced their brood production. In strong contrast to A. mellifera; however, M. subnitida did not significantly increase its pollen foraging activity under poor pollen store conditions. This difference concerning the regulation of pollen foraging may be due to differences regarding the mechanism of brood provisioning. Honey bees progressively feed young larvae and, consequently, require a constant pollen supply. Stingless bees, by contrast, mass-provision their brood cells and temporary absence of pollen storage will not immediately result in substantial brood loss.

  12. Growth, behaviour of broods and weather-related variation in breeding productivity of Curlew Sandpipers Calidris ferruginea

    NARCIS (Netherlands)

    Schekkerman, H; Van Roomen, MWJ; Underhill, LG

    1998-01-01

    Growth and survival of chicks and movements of broods were studied in Curlew Sandpipers in N.E. Taimyr, Siberia, in 1991. Breeding was synchronised, 73% of 30 clutches hatching during 10-15 July. Nests were distributed clumped in dry frost-heaved tundra. Broods were tended by females only and moved

  13. Growth, behaviour of broods and weather-related variation in breeding productivity of curlew sandpipers Calidris ferruginea

    NARCIS (Netherlands)

    Schekkerman, H.; Roomen, van M.J.W.; Underhill, L.G.

    1998-01-01

    Growth and survival of chicks and movements of broods were studied in Curlew Sandpipers in N.E. Taimyr, Siberia, in 1991. Breeding was synchronised, 73% of 30 clutches hatching during 10-15 July. Nests were distributed clumped in dry frost-heaved tundra. Broods were tended by females only and moved

  14. 40 CFR 180.1064 - Tomato pinworm insect pheromone; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Tomato pinworm insect pheromone... RESIDUES IN FOOD Exemptions From Tolerances § 180.1064 Tomato pinworm insect pheromone; exemption from the... residues of both components of the tomato pinworm insect pheromone (E)-4-tridecen-1-yl acetate and...

  15. 40 CFR 180.1153 - Lepidopteran pheromones; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Lepidopteran pheromones; exemption... FOOD Exemptions From Tolerances § 180.1153 Lepidopteran pheromones; exemption from the requirement of a tolerance. Lepidopteran pheromones that are naturally occurring compounds, or identical or...

  16. Ontogeny of Alarm pheromone production in the fire ant, Solenopsis invicta

    Science.gov (United States)

    Alarm pheromones are an essential part of a complex of pheromone interactions that contribute to the maintenance of colony integrity and sociality in social insects. Recently, we identified 2-ethyl-3,6-dimethylpyrazine as an alarm pheromone component of the fire ant, Solenopsis invicta. We continued...

  17. 40 CFR 180.1124 - Arthropod pheromones; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Arthropod pheromones; exemption from... FOOD Exemptions From Tolerances § 180.1124 Arthropod pheromones; exemption from the requirement of a tolerance. Arthropod pheromones, as described in § 152.25(b) of this chapter, when used in retrievably...

  18. Relative abundance and flight phenology of two pheromone types of Acrobasis nuxvorella (Lepidoptera: Pyralidae).

    Science.gov (United States)

    Hartfield, E A; Harris, M K; Medina, R F

    2011-08-01

    Two synthetic sex pheromones have been developed and are currently used to detect the flight of the pecan nut casebearer, Acrobasis nuxvorella Neunzig, the most damaging pest of pecan [Carya illinoinensis (Wangenh.) K. Koch]. One pheromone (referred to as standard) is attractive to moths in the southern United States, but not in Mexico. The other pheromone (referred to as Mexican) is attractive to moths in the southern United States and in Mexico. These two pheromones have been implemented by producers as an important tool in monitoring the activity of this pest and have allowed for more efficient pesticide use. In the future, these pheromones could be used as a means of population reduction through pheromone based control methods. Trapping data taken over a 3-yr period were used to determine if phenological differences exist between pheromone types of pecan nut casebearer. The relative abundance of each pheromone type at several locations in the United States also was evaluated. Results of this study indicate that no phenological differences exist between the two pheromone types studied in the United States and that significantly more males are attracted to field-deployed pheromone traps baited with the standard pheromone than to traps baited with the Mexican pheromone.

  19. 40 CFR 180.1080 - Plant volatiles and pheromone; exemptions from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Plant volatiles and pheromone... RESIDUES IN FOOD Exemptions From Tolerances § 180.1080 Plant volatiles and pheromone; exemptions from the... pheromone Z-2-isopropenyl-1-methylcyclobutaneethanol; Z-3,3-dimethyl-Δ1,β-cyclohexaneethanol;...

  20. Isolation of a pyrazine alarm pheromone component from the fire ant, Solenopsis invicta.

    Science.gov (United States)

    Vander Meer, Robert K; Preston, Catherine A; Choi, Man-Yeon

    2010-02-01

    Alarm pheromones in social insects are an essential part of a complex of pheromone interactions that contribute to the maintenance of colony integrity and sociality. The alarm pheromones of ants were among the first examples of animal pheromones identified, primarily because of the large amount of chemical produced and the distinctive responses of ants to the pheromone. However, the alarm pheromone of the fire ant, Solenopsis invicta, eluded identification for over four decades. We identified 2-ethyl-3,6-dimethylpyrazine as an alarm pheromone component of S. invicta. Worker fire ants detect the pyrazine alarm pheromone at 30 pg/ml, which is comparable to alarm pheromone sensitivities reported for other ant species. The source of this alarm pheromone are the mandibular glands, which, in fire ants, are not well developed and contain only about 300 pg of the compound, much less than the microgram quantities of alarm pheromones reported for several other ant species. Female and male sexuals and workers produce the pyrazine, which suggests that it may be involved in fire ant mating flight initiation, as well as the typical worker alarm response. This is the first report of 2-ethyl-3,6-dimethylpyrazine from a Solenopsis species and the first example of this alkaloid functioning as an alarm pheromone.

  1. Analysis of the sex pheromones of Symmetrischema tangolias and Scrobipalpuloides absoluta.

    NARCIS (Netherlands)

    Griepink, F.C.

    1996-01-01

    Sex pheromones are substances which are used by insects to attract a partner with the intention to mate. Pheromones are essential for the species survival because without them the partner cannot be located. When the chemical structures are known, the sex pheromones could be applied for pest control

  2. Candidate pheromone receptors of codling moth Cydia pomonella respond to pheromones and kairomones

    OpenAIRE

    Alberto Maria Cattaneo; Francisco Gonzalez; Bengtsson, Jonas M.; Corey, Elizabeth A.; Emmanuelle Jacquin-Joly; Nicolas Montagné; Umberto Salvagnin; Walker, William B.; Peter Witzgall; Gianfranco Anfora; Yuriy V. Bobkov

    2017-01-01

    Olfaction plays a dominant role in the mate-finding and host selection behaviours of the codling moth (Cydia pomonella), an important pest of apple, pear and walnut orchards worldwide. Antennal transcriptome analysis revealed a number of abundantly expressed genes related to the moth olfactory system, including those encoding the olfactory receptors (ORs) CpomOR1, CpomOR3 and CpomOR6a, which belong to the pheromone receptor (PR) lineage, and the co-receptor (CpomOrco). Using heterologous expr...

  3. Proteomic and UTR analyses of a rapidly evolving hypervariable family of vertebrate pheromones.

    Science.gov (United States)

    Wilburn, Damien B; Bowen, Kathleen E; Gregg, Ronald G; Cai, Jian; Feldhoff, Pamela W; Houck, Lynne D; Feldhoff, Richard C

    2012-07-01

    During the annual mating season, the mental gland of male plethodontid salamanders diverts its protein synthesizing capacity to the production of courtship pheromones that increase female receptivity. Plethodontid modulating factor (PMF), a highly disulfide-bonded 7-kDa pheromone, shows unusual hypervariability with each male expressing >30 isoforms. Twenty-eight PMFs were purified and matched by proteomic analyses to cDNA sequences. In contrast to coding sequence hypervariability, the untranslated regions (UTRs) show extraordinary conservation, no predicted microRNA binding sites, and an overlapping triplet polyadenylation signal. Full-length cDNA sequencing revealed three PMF gene classes containing subclasses of clustered sequences that support ≥ 13 PMF gene duplications. The unusual phenomena of hypervariable coding regions embedded within extremely conserved UTRs is proposed to occur by a disjunctive evolutionary process. During the short courtship season, the UTRs are hypothesized to subsume and coordinate the transcriptional and translational regulatory mechanisms of the mental gland. PMF, as a secreted protein with limited metabolic feedback in the male, is under minimal mutational restraint and thus has experienced highly accelerated rates of evolution. Consequently, plethodontid salamanders may provide a unique model for furthering our understanding of the selective forces that determine differential rates of gene duplication and evolution in protein families.

  4. Feminization of pheromone-sensing neurons affects mating decisions in Drosophila males

    Directory of Open Access Journals (Sweden)

    Beika Lu

    2014-01-01

    The response of individual animals to mating signals depends on the sexual identity of the individual and the genetics of the mating targets, which represent the mating social context (social environment. However, how social signals are sensed and integrated during mating decisions remains a mystery. One of the models for understanding mating behaviors in molecular and cellular terms is the male courtship ritual in the fruit fly (Drosophila melanogaster. We have recently shown that a subset of gustatory receptor neurons (GRNs that are enriched in the male appendages and express the ion channel ppk23 play a major role in the initiation and maintenance of male courtship via the perception of cuticular contact pheromones, and are likely to represent the main chemosensory pathway that influences mating decisions by males. Here we show that genetic feminization of ppk23-expressing GRNs in male flies resulted in a significant increase in male–male sexual attraction without an apparent impact on sexual attraction to females. Furthermore, we show that this increase in male–male sexual attraction is sensory specific, which can be modulated by variable social contexts. Finally, we show that feminization of ppk23-expressing sensory neurons lead to major transcriptional shifts, which may explain the altered interpretation of the social environment by feminized males. Together, these data indicate that the sexual cellular identity of pheromone sensing GRNs plays a major role in how individual flies interpret their social environment in the context of mating decisions.

  5. Pheromonal Communication in the European House Dust Mite, Dermatophagoides pteronyssinus

    Directory of Open Access Journals (Sweden)

    Johannes L.M. Steidle

    2014-08-01

    Full Text Available Despite the sanitary importance of the European house dust mite Dermatophagoides pteronyssinus (Trouessart, 1897, the pheromonal communication in this species has not been sufficiently studied. Headspace analysis using solid phase micro extraction (SPME revealed that nerol, neryl formate, pentadecane, (6Z,9Z-6,9-heptadecadiene, and (Z-8-heptadecene are released by both sexes whereas neryl propionate was released by males only. Tritonymphs did not produce any detectable volatiles. In olfactometer experiments, pentadecane and neryl propionate were attractive to both sexes as well as to tritonymphs. (Z-8-heptadecene was only attractive to male mites. Therefore it is discussed that pentadecane and neryl propionate are aggregation pheromones and (Z-8-heptadecene is a sexual pheromone of the European house dust mite D. pteronyssinus. To study the potential use of pheromones in dust mite control, long-range olfactometer experiments were conducted showing that mites can be attracted to neryl propionate over distances of at least 50 cm. This indicates that mite pheromones might be useable to monitor the presence or absence of mites in the context of control strategies.

  6. Male Courtship Pheromones Induce Cloacal Gaping in Female Newts (Salamandridae).

    Science.gov (United States)

    Janssenswillen, Sunita; Bossuyt, Franky

    2016-01-01

    Pheromones are an important component of sexual communication in courting salamanders, but the number of species in which their use has been demonstrated with behavioral evidence remains limited. Here we developed a behavioral assay for demonstrating courtship pheromone use in the aquatically courting Iberian ribbed newt Pleurodeles waltl. By performing an in-depth study of the courtship behavior, we show that females invariably open their cloaca (cloacal gaping) before engaging in pinwheel behavior, the circling movement that is the prelude to spermatophore uptake. In contrast, cloacal gaping was not observed in failed courtships, where females escaped or displayed thanatosis. Since gaping mainly occurred during male amplexus and cloacal imposition, which is the obvious period of pheromone transfer, we next investigated whether male courtship water (i.e., water holding courtship pheromones) alone was able to induce this reaction in females. These tests showed that courtship water induced cloacal gaping significantly more than water, even in the absence of a male. Cloacal gaping thus provides a simple and robust test for demonstrating courtship pheromone use in the Iberian ribbed newt. Since opening the cloaca is an essential prerequisite for spermatophore pick-up in all internally fertilizing salamanders, we hypothesize that variations on this assay will also be useful in several other species.

  7. Pheromones and Other Semiochemicals for Monitoring Rare and Endangered Species.

    Science.gov (United States)

    Larsson, Mattias C

    2016-09-01

    As global biodiversity declines, biodiversity and conservation have become ever more important research topics. Research in chemical ecology for conservation purposes has not adapted to address this need. During the last 10-15 years, only a few insect pheromones have been developed for biodiversity and conservation studies, including the identification and application of pheromones specifically for population monitoring. These investigations, supplemented with our knowledge from decades of studying pest insects, demonstrate that monitoring with pheromones and other semiochemicals can be applied widely for conservation of rare and threatened insects. Here, I summarize ongoing conservation research, and outline potential applications of chemical ecology and pheromone-based monitoring to studies of insect biodiversity and conservation research. Such applications include monitoring of insect population dynamics and distribution changes, including delineation of current ranges, the tracking of range expansions and contractions, and determination of their underlying causes. Sensitive and selective monitoring systems can further elucidate the importance of insect dispersal and landscape movements for conservation. Pheromone-based monitoring of indicator species will also be useful in identifying biodiversity hotspots, and in characterizing general changes in biodiversity in response to landscape, climatic, or other environmental changes.

  8. Revisiting fifty years of research on pheromone signaling in ciliates.

    Science.gov (United States)

    Luporini, Pierangelo; Pedrini, Bill; Alimenti, Claudio; Vallesi, Adriana

    2016-08-01

    Among protists, pheromones have been identified in a great variety of algal species for their activity in driving gamete-gamete interactions for fertilization. Analogously in ciliates, pheromones have been identified for their activity in inducing the sexual phenomenon of conjugation. Although this identification was pioneered by Kimball more than fifty years ago, an effective isolation and chemical characterization of ciliate pheromones has remained confined to species of Blepharisma, Dileptus and Euplotes. In Euplotes species, in which the molecular structures have been determined, pheromones form species-specific families of structurally homologous helical, cysteine-rich, highly-stable proteins. Being structurally homologous, they can bind cells in competition with one another, raising interesting functional analogies with the families of growth factors and cytokines that regulate cell differentiation and development in higher organisms. In addition to inducing conjugation by binding cells in heterologous fashion, Euplotes pheromones act also as autocrine growth factors by binding to, and promoting the vegetative reproduction of the same cells from which they originate. This autocrine activity is most likely primary, providing a concrete example of how the original function of a molecule can be obscured during evolution by the acquisition of a new one.

  9. Male Courtship Pheromones Induce Cloacal Gaping in Female Newts (Salamandridae.

    Directory of Open Access Journals (Sweden)

    Sunita Janssenswillen

    Full Text Available Pheromones are an important component of sexual communication in courting salamanders, but the number of species in which their use has been demonstrated with behavioral evidence remains limited. Here we developed a behavioral assay for demonstrating courtship pheromone use in the aquatically courting Iberian ribbed newt Pleurodeles waltl. By performing an in-depth study of the courtship behavior, we show that females invariably open their cloaca (cloacal gaping before engaging in pinwheel behavior, the circling movement that is the prelude to spermatophore uptake. In contrast, cloacal gaping was not observed in failed courtships, where females escaped or displayed thanatosis. Since gaping mainly occurred during male amplexus and cloacal imposition, which is the obvious period of pheromone transfer, we next investigated whether male courtship water (i.e., water holding courtship pheromones alone was able to induce this reaction in females. These tests showed that courtship water induced cloacal gaping significantly more than water, even in the absence of a male. Cloacal gaping thus provides a simple and robust test for demonstrating courtship pheromone use in the Iberian ribbed newt. Since opening the cloaca is an essential prerequisite for spermatophore pick-up in all internally fertilizing salamanders, we hypothesize that variations on this assay will also be useful in several other species.

  10. [Study on trace component in sex pheromones of Dendrolimus spp].

    Science.gov (United States)

    Kong, Xiangbo; Zhang, Zhen; Wang, Hongbin; Zhao, Chenghua

    2005-07-01

    Two compounds were isolated, as sex pheromone components, from the abdominal tips of the female pine caterpillar moth, Dendrolimus kikuchii. The major component was identified as (Z,E)-5,7-dodecadien-1-yl acetate by gas chromatography and mass spectrometry. There are some difficulties to elucidate the structure of the minor component due to its trace and coelution with other components. The derivatives of alkaline methanolysis and reacetylation of pheromone gland extracts of D. kikuchii were analyzed by high-resolution gas chromatography, which was performed to verify the functional group and stereo isomers of the trace component in the pheromone gland extracts. The trace component was characterized as (Z,E) -5,7-dodecadienol via microchemical reaction. The advantages of the conversion of acetates to corresponding alcohols or of alcohols to the corresponding acetates in identifying the trace component of pheromone gland extracts of D. kikuchii were discussed. The importance of identifying the trace component in pheromone chemical communication system of insects is emphasized.

  11. Post-fledging brood and care division in the roseate tern (Sterna dougallii)

    Science.gov (United States)

    Watson, M.J.; Spendelow, J.A.; Hatch, J.J.

    2012-01-01

    Extended post-fledging parental care is an important aspect of parental care in birds, although little studied due to logistic difficulties. Commonly, the brood is split physically (brood division) and/or preferential care is given to a subset of the brood by one parent or the other (care division). Among gulls and tern (Laridae), males and females generally share parental activities during the pre-fledging period, but the allocation of parental care after fledging is little documented. This study examined the behaviour of male and female roseate terns (Sterna dougallii) during the late chick-rearing and early post-fledging periods, and in particular the amount of feeds and the time spent in attendance given to individual chicks/fledglings. Pre-fledging parental care was biparental in all cases. Post-fledging parental care was dependent on the number of fledglings in the brood. Males and females continued biparental care in clutches with one surviving fledgling, while in two-fledgling clutches, males fed the A-fledgling while females fed the B-fledgling. Overall, there was no difference in attendance, only in feeds. This division of care may be influenced by the male only being certain of the paternity of the A-chick but not by chick sex. ?? 2011 Japan Ethological Society and Springer.

  12. Selecting honey bees for worker brood that reduces the reproduction of Varroa destructor

    Science.gov (United States)

    We investigated an effect of Apis mellifera worker brood on the reproduction of Varroa destructor as a resistance trait by conducting seven generations of bidirectional selection. Initial tests showed two-fold differences in mite fecundity (progeny per foundress mites) between colonies of different...

  13. Histochemistry and histoenzymology of the hydatid cyst (Echinococcus granulosus Batsch, 1786). II. Scolices and brood capsules.

    Science.gov (United States)

    Reissenweber, N J; Vercelli-Retta, J; Siri, A M; Lozano, W

    1975-12-11

    Scolices and brood capsules of healthy hydatid cysts from lungs of human patients were studied with histochemical and histoenzymatic methods. The subtegumental and flame cells were sepcially rich in glycogen, RNA and some dehydrogenases such as SDH, MDH, NADH-reductase and G-6-PDH. The rostellar zone or invaginated pole, an area of marked contractile movements, showed intense activity in ATP'ase and simple esterase. The so-called excretory pole shows strong activity in simple esterases, lipase, beta-HBH, alpha-GDH and NADPH-reductase. Lipids are also abundant in this zone implying the important role of this metabolic path in the development of the parasite. Intense activity in alkaline phosphatase was observed in cells associated to the calcereous corpuscles. The largest corpuscles were devoid of enzymatic activity. The enzyme could play some role in the calcification of the corpuscles. Wide enzymatic variations are described according to morphology being orthoscolices the most rich in enzyme activity. Accumulations of small cells surrounded by specialized cells on the germinal membrane are interpreted as the origin or "embryo" of brood capsules. Some enzymes detected in the wall of mature brood capsules depicted alternating types of cells. Some of them are positive for ATP'ase that may be related to active transport of substances across the brood capsule wall. The intenst ATP'ase activity at the stalks of scolices may be similarly interpreted. However, a miosine-like activity is a more feasible explanation since this area showed striking contractile movements in vivo.

  14. Escalation of a coevolutionary arms race through host rejection of brood parasitic young.

    Science.gov (United States)

    Langmore, Naomi E; Hunt, Sarah; Kilner, Rebecca M

    2003-03-13

    Cuckoo nestlings that evict all other young from the nest soon after hatching impose a high reproductive cost on their hosts. In defence, hosts have coevolved strategies to prevent brood parasitism. Puzzlingly, they do not extend beyond the egg stage. Thus, hosts adept at recognizing foreign eggs remain vulnerable to exploitation by cuckoo nestlings. Here we show that the breach of host egg defences by cuckoos creates a new stage in the coevolutionary cycle. We found that defences used during the egg-laying period by host superb fairy-wrens (Malurus cyaneus) are easily evaded by the Horsfield's bronze-cuckoo (Chrysococcyx basalis), a specialist fairy-wren brood parasite. However, although hosts never deserted their own broods, they later abandoned 40% of nests containing a lone Horsfield's bronze-cuckoo nestling, and 100% of nests with a lone shining bronze-cuckoo nestling (Chrysococcyx lucidus), an occasional fairy-wren brood parasite. Our experiments demonstrate that host discrimination against evictor-cuckoo nestlings is possible, and suggest that it has selected for the evolution of nestling mimicry in bronze-cuckoos.

  15. Latitudinal variation in parental energy expenditure during brood rearing in the great tit

    NARCIS (Netherlands)

    Sanz, Juan José; Tinbergen, Joost M.; Moreno, J.; Orell, Markku; Verhulst, Simon

    2000-01-01

    The variation in time and energy allocation of female great tits, Pants major, was studied in five different European populations across a latitudinal gradient. Daily energy expenditure (DEE) was measured in fe males tending 12-day-old broods. The number of daylight hours used by the parents to coll

  16. Foot-mediated incubation: Nazca booby (Sula granti) feet as surrogate brood patches.

    Science.gov (United States)

    Morgan, Stephanie M; Ashley-Ross, Miriam A; Anderson, David J

    2003-01-01

    Incubation in most avian species involves transferring heat from parent to egg through a highly vascularized brood patch. Some birds, however, do not develop a brood patch. Unusual among birds, these species hold their eggs under the webs of their feet, but the role of the feet in heat transfer is uncertain. Often the webs are positioned between the feathered abdomen and the egg during incubation, suggesting that either the abdomen, the feet, or both could transfer heat to the egg. We studied heat transfer from foot webs to eggs during incubation in Nazca boobies by spatially separating the feet from the abdomen using an oversized egg. We found that feet transfer heat to eggs independently of any heat that may be transferred from the abdomen. In addition, we found that incubating boobies had significantly greater vascularization in their foot webs, measured as a percentage of web area covered by vessels, than nonincubating boobies. We also found that males, whether incubating or nonincubating, had significantly less web vascularization than females. We concluded that vascularized Nazca booby feet function in the same way during incubation that vascularized brood patches do, acting as surrogate brood patches.

  17. Should I stay or should I go? Female brood desertion and male counterstrategy in rock sparrows

    DEFF Research Database (Denmark)

    Griggio, Matteo; Matessi, Giuliano; Pilastro, Andrea

    2005-01-01

    Brood desertion involves a series of interactions between the members of a pair. This process is likely to be based on either member's perception of the other's propensity to desert. We manipulated this perception in males by experimentally increasing female body mass in the rock sparrow (Petroni...

  18. Is extrapair mating random? On the probability distribution of extrapair young in avian broods

    NARCIS (Netherlands)

    Brommer, Jon E.; Korsten, Peter; Bouwman, Karen A.; Berg, Mathew L.; Komdeur, Jan

    2007-01-01

    A dichotomy in female extrapair copulation (EPC) behavior, with some females seeking EPC and others not, is inferred if the observed distribution of extrapair young (EPY) over broods differs from a random process on the level of individual offspring (binomial, hypergeometrical, or Poisson). A review

  19. Fledgling sex ratios in relation to brood size in size-dimorphic altricial birds

    NARCIS (Netherlands)

    Dijkstra, Cor; Daan, Serge; Pen, Ido

    1998-01-01

    In six species of dimorphic raptors (females larger than males) and one passerine (males larger than females), the sex ratio at fledging varied systematically with brood size at fledging. In all species the strongest bias toward the smaller sex was established in the largest as well as the smallest

  20. Brood development of different carniolan bee ecotypes (Apis mellifera carnica Pollmann, 1879

    Directory of Open Access Journals (Sweden)

    Dragan Bubalo

    2002-09-01

    Full Text Available Brood development of different carniolan honeybee ecotypes (Apis mellifera carnica Pollmann, 1879 was carried out in condition of pannonian and alpine climate. The colonies on both experimental apiaries were divided in the three groups, each 12 queens, of alpine (Austria, subalpine (Slovenia and pannonian (Croatia ecotype. The experiment was designed to monitor development of brood, the total number of laid cells and colony strength. In particular part of the year, experimental ecotypes shown significant differences in area of unsealed and sealed brood in both climate. In the whole season there was not established significant difference between ecotypes regarding to development of drone brood. In pannonian climate, in comparison to alpine climate, the number of laid eggs was higher for all ecotypes. Pannonian ecotype did not recognize all food sources in the new environment, which could be seen in the lack of pollen in the colonies at the alpine climate during last two measuriments. The lack of pollen affected the weakening of the colonies laiter in the season.

  1. Brooding is Related to Neural Alterations during Autobiographical Memory Retrieval in Aging

    Directory of Open Access Journals (Sweden)

    Sophia Schneider

    2016-09-01

    Full Text Available Brooding rumination is considered a central aspect of depression in midlife. As older people tend to review their past, rumination tendency might be particularly crucial in late life since it might hinder older adults to adequately evaluate previous events. We scanned 22 non-depressed older adults with varying degrees of brooding tendency with functional magnetic resonance imaging while they performed the construction and elaboration of autobiographical memories. Behavioral findings demonstrate that brooders reported lower mood states, needed more time for memory construction and rated their memories as less detailed and less positive. On the neural level, brooding tendency was related to increased amygdala activation during the search for specific memories and reduced engagement of cortical networks during elaboration. Moreover, coupling patterns of the subgenual cingulate cortex with the hippocampus and the amygdala predicted details and less positive valence of memories in brooders. Our findings support the hypothesis that ruminative thinking interferes with the search for specific memories while facilitating the uncontrolled retrieval of negatively biased self-schemes. The observed neurobehavioral dysfunctions might put older people with brooding tendency at high risk for becoming depressed when reviewing their past. Training of autobiographical memory ability might therefore be a promising approach to increase resilience against depression in late-life.

  2. Individual Pheromone Signature in Males: Prerequisite for Pheromone-Mediated Mate Assessment in the Central American Locust, Schistocerca Piceifrons.

    Science.gov (United States)

    Stahr, Christiane; Seidelmann, Karsten

    2016-12-01

    Living in high-density groups of animals has advantages and disadvantages for mating. The advantage of facilitated mate finding is compromised by difficulties in protecting a suitable partner from competitors. Thus, males regularly are faced with increased competition for sperm, and females with harassment by males at high population densities. To cope with these problems, mating tactics and mate choice mechanisms have to be adjusted. An adaptation to gregarious condition observed in locusts includes the use of male-emitted pheromones. Males of the Central American locust, Schistocerca piceifrons, release sex-specific volatiles, which were identified as phenethyl alcohol (synonym: phenyl-ethyl-alcohol, 2-phenyl-1-ethanol, 2-phenylethanol, PEA), (Z)-3-nonen-1-ol (3-Nol), and (Z)-2-octen-1-ol (2-Ool). The emission of the two major compounds, PEA and 3-Nol, was restricted to crowded conditions. Furthermore, the release of both volatiles was coupled to males reaching sexual maturity, indicating a function in reproductive behavior. However, neither the single substances nor their mixtures were attractive or repellent to the locusts. Instead, females prefer the sperm of high pheromone-emitting males to fertilize their ova. In this way, the male-specific volatiles act as mate assessment pheromones utilized in a context of cryptic female choice. This function is well supported by the highly variable but individual-specific emission rates of the three compounds. Schistocerca piceifrons males release a virtually unique personal pheromone signature, a prerequisite for mate assessment pheromones.

  3. Assessment of pheromone production and response in fission yeast by a halo test of induced sporulation

    DEFF Research Database (Denmark)

    Egel, R; Willer, M; Kjaerulff, S

    1994-01-01

    We describe a rapid, sensitive and semi-quantitative plate assay for monitoring pheromone activity in the fission yeast Schizosaccharomyces pombe. It is based on the observation that meiosis requires stimulation by pheromone and exploits diploid strains that will only sporulate after addition...... of exogenous pheromone. The tester strains are heterozygous for mating type, are non-switching, and are mutated in one of the early subfunctions (either mat1-Mc or mat1-Pc), so that meiosis is only induced after exposure to exogenous pheromone (M-factor or P-factor, respectively). Pheromone activity...

  4. Long-term coevolution between avian brood parasites and their hosts.

    Science.gov (United States)

    Soler, Manuel

    2014-08-01

    Coevolutionary theory predicts that the most common long-term outcome of the relationships between brood parasites and their hosts should be coevolutionary cycles based on a dynamic change selecting the currently least-defended host species, given that when well-defended hosts are abandoned, hosts will be selected to decrease their defences as these are usually assumed to be costly. This is assumed to be the case also in brood parasite-host systems. Here I examine the frequency of the three potential long-term outcomes of brood parasite-host coevolution (coevolutionary cycles, lack of rejection, and successful resistance) in 182 host species. The results of simple exploratory comparisons show that coevolutionary cycles are very scarce while the lack of rejection and successful resistance, which are considered evolutionary enigmas, are much more frequent. I discuss these results considering (i) the importance of different host defences at all stages of the breeding cycle, (ii) the role of phenotypic plasticity in long-term coevolution, and (iii) the evolutionary history of host selection. I suggest that in purely antagonistic coevolutionary interactions, such as those involving brood parasites and their hosts, that although cycles will exist during an intermediate phase of the interactions, the arms race will end with the extinction of the host or with the host acquiring successful resistance. As evolutionary time passes, this resistance will force brood parasites to use previously less suitable host species. Furthermore, I present a model that represents the long-term trajectories and outcomes of coevolutionary interactions between brood parasites and their hosts with respect to the evolution of egg-rejection defence. This model suggests that as an increasing number of species acquire successful resistance, other unparasitized host species become more profitable and their parasitism rate and the costs imposed by brood parasitism at the population level will

  5. Mammalian pheromones: emerging properties and mechanisms of detection.

    Science.gov (United States)

    Stowers, Lisa; Kuo, Tsung-Han

    2015-10-01

    The concept of mammalian pheromones was established decades before the discovery of any bioactive ligands. Therefore, their molecular identity, native sources, and the meaning of their detection has been largely speculative. There has been recent success in identifying a variety of candidate mouse pheromones and other specialized odors. These discoveries reveal that mammalian pheromones come in a variety of ligand types and they are detected by sensory neurons that are pre-set to promote an array of social and survival behaviors. Importantly, recent findings show that they activate molecularly diverse sensory neurons that differ from canonical odorant detectors. These novel sensory neurons hold future promise to unlock the mystery of how their detection is hardwired to generate behavior.

  6. Regulation of Isoprenoid Pheromone Biosynthesis in Bumblebee Males.

    Science.gov (United States)

    Prchalová, Darina; Buček, Aleš; Brabcová, Jana; Žáček, Petr; Kindl, Jiří; Valterová, Irena; Pichová, Iva

    2016-02-02

    Males of the closely related species Bombus terrestris and Bombus lucorum attract conspecific females by completely different marking pheromones. MP of B. terrestris and B. lucorum pheromones contain mainly isoprenoid (ISP) compounds and fatty acid derivatives, respectively. Here, we studied the regulation of ISP biosynthesis in both bumblebees. RNA-seq and qRT-PCR analyses indicated that acetoacetyl-CoA thiolase (AACT), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR), and farnesyl diphosphate synthase (FPPS) transcripts are abundant in the B. terrestris labial gland. Maximal abundance of these transcripts correlated well with AACT enzymatic activity detected in the LG extracts. In contrast, transcript abundances of AACT, HMGR, and FPPS in B. lucorum were low, and AACT activity was not detected in LGs. These results suggest that transcriptional regulation plays a key role in the control of ISP biosynthetic gene expression and ISP pheromone biosynthesis in bumblebee males.

  7. desat1 and the evolution of pheromonal communication in Drosophila.

    Science.gov (United States)

    Bousquet, François; Houot, Benjamin; Chauvel, Isabelle; Dupas, Stéphane; Ferveur, Jean-François

    2009-07-01

    The evolution of communication is a fundamental biological problem. The genetic control of the signal and its reception must be tightly coadapted, especially in interindividual sexual communication. However, there is very little experimental evidence for tight genetic linkage connecting the emission of a signal and its reception. In Drosophila melanogaster, desat1 is the first known gene that simultaneously affects the emission and the perception of sex pheromones. Our experiments show that both aspects of pheromonal communication (the emission and the perception of sex pheromones) depend on distinct genetic control and may result from tissue-specific expression of different transcripts, all coding for the same desaturase. Therefore, and given the high conservation of its coding region, the pleiotropic activity of the desat1 gene may have arisen from an evolutionary process that shaped its regulatory regions.

  8. Pheromone use for insect control: present status and prospect in Bangladesh

    Directory of Open Access Journals (Sweden)

    Md. Azharul Islam

    2012-06-01

    Full Text Available The insect’s world is filled with many odors. Insects use these odors to cue them in a variety of complex social behaviors, including courtship, mating, and egg laying. Scientists and pest control specialists have known about these complex communication systems for decades. The main aim of this study was to visualize the availability, trends and differences in the sources of pheromone control in agricultural growth of Bangladesh. It also concerned on constrains and present use of pheromone and their possible recommendation on behalf of Bangladesh agriculture. It concentrated on the data during last three decades (1980-2010, comprising status of pheromone use in Bangladesh agriculture and its future. Review revealed that Bangladesh has been enormously successful in increasing pheromone use in agricultural production (especially for vegetables. Understanding of the nature of pheromones and their potential for pest control along with the future prospective of pheromone technique in agriculture were stated. Since the pheromone, technologies for control of major crop pests in Bangladesh are still limited. So that this review emphasized on more attention to the authority to increase the research works and project facilities related to develop and promote pheromone techniques. It is highly recommended to increase availability of pheromone in market, more investment in research and development, introduction of newly identified pheromone for specific pest, to assist government and non-government organizations to work with farmers to reduce harmful insecticide use and promote pheromone tactics as one part of integrated crop management (ICM.

  9. Causes and consequences of variability in peptide mating pheromones of ascomycete fungi.

    Science.gov (United States)

    Martin, Simon H; Wingfield, Brenda D; Wingfield, Michael J; Steenkamp, Emma T

    2011-07-01

    The reproductive genes of fungi, like those of many other organisms, are thought to diversify rapidly. This phenomenon could be associated with the formation of reproductive barriers and speciation. Ascomycetes produce two classes of mating type-specific peptide pheromones. These are required for recognition between the mating types of heterothallic species. Little is known regarding the diversity or the extent of species specificity in pheromone peptides among these fungi. We compared the putative protein-coding DNA sequences of the 2 pheromone classes from 70 species of Ascomycetes. The data set included previously described pheromones and putative pheromones identified from genomic sequences. In addition, pheromone genes from 12 Fusarium species in the Gibberella fujikuroi complex were amplified and sequenced. Pheromones were largely conserved among species in this complex and, therefore, cannot alone account for the reproductive barriers observed between these species. In contrast, pheromone peptides were highly diverse among many other Ascomycetes, with evidence for both positive diversifying selection and relaxed selective constraint. Repeats of the α-factor-like pheromone, which occur in tandem arrays of variable copy number, were found to be conserved through purifying selection and not concerted evolution. This implies that sequence specificity may be important for pheromone reception and that interspecific differences may indeed be associated with functional divergence. Our findings also suggest that frequent duplication and loss causes the tandem repeats to experience "birth-and-death" evolution, which could in fact facilitate interspecific divergence of pheromone peptide sequences.

  10. System of forest insect pheromone communication: stability of «information» molecules to environmental factors

    Directory of Open Access Journals (Sweden)

    V. G. Soukhovolsky

    2016-06-01

    Full Text Available Features of external environmental factors (such as electromagnetic radiation in certain spectral bands influencing pheromone molecules, which are carriers of information for forest insects in the search of the opposite sex, were examined. Stability of pheromone molecules for external influences has been studied for siberian moth Dendrolimus superans sibiricus Tschetv., pine moth Dendrilimus pini L., gypsy moth Lymantria dispar L., for xylophages Ips typographus L., Monochamus urussovi Fish. and Monochamus galloprovincialis Oliv. Properties of pheromone molecules were evaluated by calculations using quantum-chemical method B3LYP. Existing methods of quantum-chemical calculations are useful for analyzing the properties of quite small and uncomplicated molecules of forest insect pheromones. The calculations showed that the molecules of insect pheromones are able to absorb light in the ultraviolet range and move into an excited state. The values of dipole moments, the wavelengths of the absorption, atomic and molecular electronic properties of pheromones in the ground and excited states were calculated. The calculations showed that for the reaction of pheromones with oxygen an energy barrier is somewhat higher than for reactions of pheromones with water vapor. The worst reaction of pheromones with water molecules likely to pheromones such molecules whose dipole moment is comparable to the dipole moment of water. Quantum-chemical characteristics of the pheromone molecules can be linked to specific behavior of the insects.

  11. Contribution of oenocytes and pheromones to courtship behaviour in Drosophila

    Directory of Open Access Journals (Sweden)

    Guenachi Ilhem

    2009-08-01

    Full Text Available Abstract Background In Drosophila, cuticular sex pheromones are long-chain unsaturated hydrocarbons synthesized from fatty acid precursors in epidermal cells called oenocytes. The species D. melanogaster shows sex pheromone dimorphism, with high levels of monoenes in males, and of dienes in females. Some biosynthesis enzymes are expressed both in fat body and oenocytes, rendering it difficult to estimate the exact role of oenocytes and of the transport of fatty acids from fat body to oenocytes in pheromone elaboration. To address this question, we RNAi silenced two main genes of the biosynthesis pathway, desat1 and desatF, in the oenocytes of D. melanogaster, without modifying their fat body expression. Results Inactivation of desat1 in oenocytes resulted in a 96% and 78% decrease in unsaturated hydrocarbons in males and females, respectively. Female pheromones (dienes showed a decrease of 90%. Inactivation of desatF, which is female-specific and responsible for diene formation, resulted in a dramatic loss of pheromones (-98% paralleled with a two-fold increase in monoenes. Courtship parameters (especially courtship latency from wild-type males were more affected by desat1 knocked-down females (courtship latency increased by four fold than by desatF knocked-down ones (+65% of courtship latency. The number of transcripts in oenocytes was estimated at 0.32 and 0.49 attomole/μg for desat1 in males and females, respectively, about half of the total transcripts in a fly. There were only 0.06 attomole/μg desatF transcripts in females, all located in the oenocytes. Conclusion Knock-down results for desat1 suggest that there must be very little transport of unsaturated precursors from fat body to the oenocytes, so pheromone synthesis occurs almost entirely through the action of biosynthesis enzymes within the oenocytes. Courtship experiments allow us to discuss the behavioral role of diene pheromones, which, under special conditions, could be replaced

  12. Effects of natural and synthetic alarm pheromone and individual pheromone components on foraging behavior of the giant Asian honey bee, Apis dorsata.

    Science.gov (United States)

    Li, Jianjun; Wang, Zhengwei; Tan, Ken; Qu, Yufeng; Nieh, James C

    2014-10-01

    Social pollinators such as honey bees face attacks from predators not only at the nest, but also during foraging. Pollinating honey bees can therefore release alarm pheromones that deter conspecifics from visiting dangerous inflorescences. However, the effect of alarm pheromone and its chemical components upon bee avoidance of dangerous food sources remains unclear. We tested the responses of giant honey bee foragers, Apis dorsata, presented with alarm pheromone at a floral array. Foragers investigated the inflorescence with natural alarm pheromone, but 3.3-fold more foragers preferred to land on the 'safe' inflorescence without alarm pheromone. Using gas chromatography-mass spectrometry analysis, we identified eight chemical components in the alarm pheromone, of which three components (1-octanol, decanal and gamma-octanoic lactone) have not previously been reported in this species. We bioassayed six major compounds and found that a synthetic mixture of these compounds elicited behaviors statistically indistinguishable from responses to natural alarm pheromone. By testing each compound separately, we show that gamma-octanoic lactone, isopentyl acetate and (E)-2-decen-1-yl acetate are active compounds that elicit significant alarm responses. Gamma-octanoic lactone elicited the strongest response to a single compound and has not been previously reported in honey bee alarm pheromone. Isopentyl acetate is widely found in the alarm pheromones of sympatric Asian honey bee species, and thus alarmed A. dorsata foragers may produce information useful for conspecifics and heterospecifics, thereby broadening the effects of alarm information on plant pollination.

  13. High frequency of multiple paternity in broods of a socially monogamous cichlid fish with biparental nest defence.

    Science.gov (United States)

    Sefc, Kristina M; Mattersdorfer, Karin; Sturmbauer, Christian; Koblmüller, Stephan

    2008-05-01

    In several animal taxa, genetic analyses have demonstrated that social monogamy and biparental brood care do not preclude polygamous reproduction. Few studies have been conducted in fish, but in fish species without alternative reproductive phenotypes, social monogamy was largely congruent with genetic parentage. In contrast to these findings, we report an exceptionally high level of multiple paternity in a socially monogamous cichlid fish with biparental nest defence (Variabilichromis moorii), inferred from microsatellite and mitochondrial data of 10 broods. Whereas all offspring in a nest shared a common mother, each brood was sired by 2 to > 10 males. None of the inferred sires was assigned a large proportion of the brood. Paternity was estimated as the minimum number of sires required to explain multilocus offspring genotypes, and as the maximum-likelihood number of sires given population allele frequencies. Analysis of simulated brood genotypes suggested that, although these two methods tend to under- and overestimate, respectively, the true number of sires, primary sires with many offspring in a brood would have been detected. Hence, the genetic data indicate that the nest tending males suffer substantial cuckoldry and provide alloparental care for a large number of unrelated fry. We have no data on the social status of the cuckolding males, but due to synchronous spawning of pairs and commitment to brood care of paired males, it is possible that most of the parasitic spawners are solitary males.

  14. Caps and gaps: a computer model for studies on brood incubation strategies in honeybees (Apis mellifera carnica)

    Science.gov (United States)

    Fehler, Manuel; Kleinhenz, Marco; Klügl, Franziska; Puppe, Frank; Tautz, Jürgen

    2007-08-01

    In addition to heat production on the comb surface, honeybee workers frequently visit open cells (“gaps”) that are scattered throughout the sealed brood area, and enter them to incubate adjacent brood cells. We examined the efficiency of this heating strategy under different environmental conditions and for gap proportions from 0 to 50%. For gap proportions from 4 to 10%, which are common to healthy colonies, we find a significant reduction in the incubation time per brood cell to maintain the correct temperature. The savings make up 18 to 37% of the time, which would be required for this task in completely sealed brood areas without any gaps. For unnatural high proportions of gaps (>20%), which may be the result of inbreeding or indicate a poor condition of the colony, brood nest thermoregulation becomes less efficient, and the incubation time per brood cell has to increase to maintain breeding temperature. Although the presence of gaps is not essential to maintain an optimal brood nest temperature, a small number of gaps make heating more economical by reducing the time and energy that must be spent on this vital task. As the benefit depends on the availability, spatial distribution and usage of gaps by the bees, further studies need to show the extent to which these results apply to real colonies.

  15. Sub-lethal effects of pesticide residues in brood comb on worker honey bee (Apis mellifera development and longevity.

    Directory of Open Access Journals (Sweden)

    Judy Y Wu

    Full Text Available BACKGROUND: Numerous surveys reveal high levels of pesticide residue contamination in honey bee comb. We conducted studies to examine possible direct and indirect effects of pesticide exposure from contaminated brood comb on developing worker bees and adult worker lifespan. METHODOLOGY/PRINCIPAL FINDINGS: Worker bees were reared in brood comb containing high levels of known pesticide residues (treatment or in relatively uncontaminated brood comb (control. Delayed development was observed in bees reared in treatment combs containing high levels of pesticides particularly in the early stages (day 4 and 8 of worker bee development. Adult longevity was reduced by 4 days in bees exposed to pesticide residues in contaminated brood comb during development. Pesticide residue migration from comb containing high pesticide residues caused contamination of control comb after multiple brood cycles and provided insight on how quickly residues move through wax. Higher brood mortality and delayed adult emergence occurred after multiple brood cycles in contaminated control combs. In contrast, survivability increased in bees reared in treatment comb after multiple brood cycles when pesticide residues had been reduced in treatment combs due to residue migration into uncontaminated control combs, supporting comb replacement efforts. Chemical analysis after the experiment confirmed the migration of pesticide residues from treatment combs into previously uncontaminated control comb. CONCLUSIONS/SIGNIFICANCE: This study is the first to demonstrate sub-lethal effects on worker honey bees from pesticide residue exposure from contaminated brood comb. Sub-lethal effects, including delayed larval development and adult emergence or shortened adult longevity, can have indirect effects on the colony such as premature shifts in hive roles and foraging activity. In addition, longer development time for bees may provide a reproductive advantage for parasitic Varroa destructor

  16. Yearly and Seasonal Variation of Breeding Parameters in a Declining Multi-Brooded Passerine, the Tree Sparrow

    OpenAIRE

    García-Navas, Vicente; Sanz, Juan José

    2012-01-01

    Over a five-year period we monitored breeding parameters in a colony of Tree Sparrows Passer montanus in central Spain. This multi-brooded species can raise one to three broods per season. In this study, we analyzed inter-brood variation in reproductive success to infer the existence of seasonal patterns. We also explored inter-annual variation of life-history traits, which is of particular interest in a declining species like the Tree Sparrow. In agreement with our expectation of a multi-bro...

  17. A dual physiological character for sexual function: libido and sexual pheromones.

    Science.gov (United States)

    Motofei, Ion G

    2009-12-01

    Human sexual response is a complex function involving many cerebral, spinal and peripheral aspects; the last are relatively known and benefit from good pharmacological control, as in the case of erectile dysfunction. Spinal cord sexual reflexes also have a good theoretical and experimental description. There is minimal understanding of the cerebral sexual processes (libido, sexual arousal, orgasm). The initial perspective was that the cerebral areas implied in sexuality exert descending stimulatory and inhibitory influences on spinal cord sexual centres/reflexes. This was a wrong supposition, which inhibited progress in this subject, with a considerable impact on a subject's individual and social life. A new approach to sexual function arises from the idea that simple neurological structures can support only simple functions, while a more complex function requires correspondingly complex anatomical structures. For this reason the spinal cord would not be able to realise the integration of multiple (spinal and psychosensorial) stimuli into a unique and coherent ejaculation response. Consequently, all mechanisms implied in human sexuality would be cerebral processes, ejaculation reflexes ascending in evolution to the cerebral level. This new evolutionary concept was developed after 2001 in five distinct articles on the cerebral duality of sexual arousal, sexual hormones, ejaculation and serotonergic receptors. During this period other published results suggested a possible cerebral duality for sexual pheromones and libido in humans. All these dual physiological aspects are integrated in this review into one neurophysiological model, thus trying to further develop the new concepts of sexual function and perhaps relational behaviour. In conclusion, ejaculation is a dual cerebral process with arousal sensation (hormonally modulated) and libido perception (pheromonally modulated) as the afferent part. Two neurophysiological axes could exist in both men and women. In this

  18. Evaluating exposure and potential effects on honeybee brood (Apis mellifera) development using glyphosate as an example.

    Science.gov (United States)

    Thompson, Helen M; Levine, Steven L; Doering, Janine; Norman, Steve; Manson, Philip; Sutton, Peter; von Mérey, Georg

    2014-07-01

    This study aimed to develop an approach to evaluate potential effects of plant protection products on honeybee brood with colonies at realistic worst-case exposure rates. The approach comprised 2 stages. In the first stage, honeybee colonies were exposed to a commercial formulation of glyphosate applied to flowering Phacelia tanacetifolia with glyphosate residues quantified in relevant matrices (pollen and nectar) collected by foraging bees on days 1, 2, 3, 4, and 7 postapplication and glyphosate levels in larvae were measured on days 4 and 7. Glyphosate levels in pollen were approximately 10 times higher than in nectar and glyphosate demonstrated rapid decline in both matrices. Residue data along with foraging rates and food requirements of the colony were then used to set dose rates in the effects study. In the second stage, the toxicity of technical glyphosate to developing honeybee larvae and pupae, and residues in larvae, were then determined by feeding treated sucrose directly to honeybee colonies at dose rates that reflect worst-case exposure scenarios. There were no significant effects from glyphosate observed in brood survival, development, and mean pupal weight. Additionally, there were no biologically significant levels of adult mortality observed in any glyphosate treatment group. Significant effects were observed only in the fenoxycarb toxic reference group and included increased brood mortality and a decline in the numbers of bees and brood. Mean glyphosate residues in larvae were comparable at 4 days after spray application in the exposure study and also following dosing at a level calculated from the mean measured levels in pollen and nectar, showing the applicability and robustness of the approach for dose setting with honeybee brood studies. This study has developed a versatile and predictive approach for use in higher tier honeybee toxicity studies. It can be used to realistically quantify exposure of colonies to pesticides to allow the

  19. Extrusion of the C-terminal helix in navel orangeworm moth pheromone-binding protein (AtraPBP1) controls pheromone binding.

    Science.gov (United States)

    Xu, Wei; Xu, Xianzhong; Leal, Walter S; Ames, James B

    2011-01-07

    The navel orangeworm, Amyelois transitella (Walker), is an agricultural insect pest that can be controlled by disrupting male-female communication with sex pheromones, a technique known as mating disruption. Insect pheromone-binding proteins (PBPs) provide fast transport of hydrophobic pheromones through aqueous sensillar lymph and promote sensitive delivery of pheromones to receptors. Here we present a mutational analysis on a PBP from A. transitella (AtraPBP1) to evaluate how the C-terminal helix in this protein controls pheromone binding as a function of pH. Pheromone binds tightly to AtraPBP1 at neutral pH, but the binding is much weaker at pH below 5. Deletion of the entire C-terminal helix (residues 129-142) causes more than 100-fold increase in pheromone-binding affinity at pH 5 and only a 1.5-fold increase at pH 7. A similar pH-dependent increase in pheromone binding is also seen for the H80A/H95A double mutant that promotes extrusion of the C-terminal helix by disabling salt bridges at each end of the helix. The single mutants (H80A and H95A) also exhibit pheromone binding at pH below 5, but with ∼2-fold weaker affinity. NMR and circular dichroism data demonstrate a large overall structural change in each of these mutants at pH 4.5, indicating an extrusion of the C-terminal helix that profoundly affects the overall structure of the low pH form. Our results confirm that sequestration of the C-terminal helix at low pH as seen in the recent NMR structure may serve to block pheromone binding. We propose that extrusion of these C-terminal residues at neutral pH (or by the mutations in this study) exposes a hydrophobic cleft that promotes high affinity pheromone binding.

  20. Modeling of Forest Insect Pheromone Communication System. Female as a Source of Information

    Directory of Open Access Journals (Sweden)

    V. G. Soukhovolsky

    2014-12-01

    Full Text Available The system of pheromone communication in insects-phyllophagous was considered in terms of its effectiveness as a communication system. A selected lepidopterous insect (Lepidoptera was chosen for analysis of pheromone communication system. We analyzed data on 250 species of insects from three families – Lasiocampidae, Geometridae, Lymantriidae. Specificity of the chemical composition of the complex pheromones and pheromone component count was assessed for all of these females. Characteristics of complexes of insect pheromones and possible female strategies of behavior were modeled using the methods of information theory, utility theory and game theory. We estimated complementarity for various types of chemical compounds in pheromone composition. The uniqueness of the pheromone signal of separate species of Lepidoptera is achieved by using a multi-component pheromone. There are no hard links between existence or absence of individual components in multi-component pheromones. The model was proposed for explanation of regularities of pheromone composition. Nonmonotonic of relative frequency of insect species curve with different number of components can be explained in terms of a trade-off between increasing the efficiency of males seeking females of the same species with an increasing number of individual components and the complexity of the synthesis of pheromones multi-component pheromones. The Kolmogorov-Smirnov test was used to assess the validity of the model description. Possible mechanisms of pheromone signal amplification studied were associated with the aggregation of a large number of individuals in a limited area. If females in the process of attracting individuals of the opposite sex are aggregated, then the source of pheromones is not a private individual, but a group of females, and the intensity of the flow of the group of molecules is defined as the intensity of pheromone release pheromones individual animals and the number of

  1. Fitness cost of pheromone production in signaling female moths.

    Science.gov (United States)

    Harari, Ally R; Zahavi, Tirtza; Thiéry, Denis

    2011-06-01

    A secondary sexual character may act as an honest signal of the quality of the individual if the trait bears a cost and if its expression is phenotypically condition dependent. The cost of increasing the trait should be tolerable for individuals in good condition but not for those in a poor condition. The trait thus provides an honest signal of quality that enables the receiver to choose higher quality mates. Evidence for sex pheromones, which play a major role in shaping sexual evolution, inflicting a signaling cost is scarce. Here, we demonstrate that the amount of the major component of the pheromone in glands of Lobesia botrana (Lepidoptera) females at signaling time was significantly greater in large than in small females, that male moths preferred larger females as mates when responding to volatile signals, and small virgin females, but not large ones, exposed to conspecific pheromone, produced, when mated, significantly fewer eggs than nonexposed females. The latter indicates a condition-dependent cost of signaling. These results are in accordance with the predictions of condition-dependent honest signals. We therefore suggest that female signaling for males using sex pheromones bears a cost and thus calling may serve as honest advertisement for female quality.

  2. Sex-specific mating pheromones in the nematode Panagrellus redivivus

    Science.gov (United States)

    Despite advances in medicine and crop genetics, nematodes remain significant human pathogens and agricultural pests. This warrants investigation of alternative strategies for pest control, such as interference with pheromone-mediated reproduction. Because only two nematode species have had their phe...

  3. The distribution of weaver ant pheromones on host trees

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2007-01-01

    for correlations between spot density, ant activity and the likelihood of being detected by an ant. Spots were only found on trees with ants. On ant-trees, spots were distributed throughout the trees but with higher densities in areas with high ant activity and pheromone densities were higher on twigs compared...

  4. Pheromones, male lures and trapping of tephritid fruit flies

    Science.gov (United States)

    The dipteran family of Tephritidae consists of many genera, of which several namely, Anastrepha, Bactrocera, Ceratitis, Dacus, Rhagoletis and Toxotrypana possess species of high economic importance as major pests of fruits and vegetables. Hitherto, pheromones isolated and identified for possible use...

  5. Development of a pheromone elution rate physical model

    Science.gov (United States)

    A first principle modeling approach is applied to available data describing the elution of semiochemicals from pheromone dispensers. These data include field data for 27 products developed by several manufacturers, including homemade devices, as well as laboratory data collected on three semiochemi...

  6. Conservation of Queen Pheromones Across Two Species of Vespine Wasps.

    Science.gov (United States)

    Oi, Cintia A; Millar, Jocelyn G; van Zweden, Jelle S; Wenseleers, Tom

    2016-11-01

    Social insects are known for their reproductive division of labor between queens and workers, whereby queens lay the majority of the colony's eggs, and workers engage mostly in non-reproductive tasks. Queens produce pheromones that signal their presence and fertility to workers, which in turn generally remain sterile. Recently, it has been discovered that specific queen-characteristic cuticular hydrocarbons (CHCs) function as queen pheromones across multiple lineages of social insects. In the common wasp, Vespula vulgaris, several long-chain linear alkanes and 3-methylalkanes were shown to act as queen signals. Here, we describe similar bioassays with a related species of highly eusocial vespine wasp, the Saxon wasp, Dolichovespula saxonica. We show that a blend of queen-characteristic hydrocarbons that are structurally related to those of the common wasp inhibit worker reproduction, suggesting conservation of queen pheromones across social wasps. Overall, our results highlight the central importance of CHCs in chemical communication among social insects in general, and as conserved queen pheromones in these social wasps in particular.

  7. Identification of a pheromone that increases anxiety in rats.

    Science.gov (United States)

    Inagaki, Hideaki; Kiyokawa, Yasushi; Tamogami, Shigeyuki; Watanabe, Hidenori; Takeuchi, Yukari; Mori, Yuji

    2014-12-30

    Chemical communication plays an important role in the social lives of various mammalian species. Some of these chemicals are called pheromones. Rats release a specific odor into the air when stressed. This stress-related odor increases the anxiety levels of other rats; therefore, it is possible that the anxiety-causing molecules are present in the stress-related odorants. Here, we have tried to identify the responsible molecules by using the acoustic startle reflex as a bioassay system to detect anxiogenic activity. After successive fractionation of the stress-related odor, we detected 4-methylpentanal and hexanal in the final fraction that still possessed anxiogenic properties. Using synthetic molecules, we found that minute amounts of the binary mixture, but not either molecule separately, increased anxiety in rats. Furthermore, we determined that the mixture increased a specific type of anxiety and evoked anxiety-related behavioral responses in an experimental model that was different from the acoustic startle reflex. Analyses of neural mechanisms proposed that the neural circuit related to anxiety was only activated when the two molecules were simultaneously perceived by two olfactory systems. We concluded that the mixture is a pheromone that increases anxiety in rats. To our knowledge, this is the first study identifying a rat pheromone. Our results could aid further research on rat pheromones, which would enhance our understanding of chemical communication in mammals.

  8. Are androgen steroids acting as pheromones in humans?

    Science.gov (United States)

    Pause, Bettina M

    2004-10-30

    In animals, chemosensory communication is successfully used to transmit behaviourally relevant information, e.g. information about sexual status, danger and social organisation. In many instances pheromones might have evolved from hormone-like substances. Consequently, a large number of studies have been carried out in humans, in order to investigate possible pheromonal properties of androgen steroids. Besides discussing the production and perception of androgen steroids, it will primarily be questioned whether their perception can alter mood and behaviour in humans. Therefore, a study has been carried out to investigate whether local preferences can be altered through androstenone exposure. It is shown that heterosexual women and homosexual men prefer seats sprayed with androstenone. However, as this effect is positively correlated with the sensitivity to androstenone, the effect might be due to a general olfactory attraction of low androstenone concentrations. In regard to the conflicting results of studies on putative human pheromones, it will finally be discussed whether the perceptual context and the individual learning history of the perceiver contribute significantly to a successful communication of pheromonal information.

  9. Parallel evolution of domesticated Caenorhabditis species targets pheromone receptor genes.

    Science.gov (United States)

    McGrath, Patrick T; Xu, Yifan; Ailion, Michael; Garrison, Jennifer L; Butcher, Rebecca A; Bargmann, Cornelia I

    2011-08-17

    Evolution can follow predictable genetic trajectories, indicating that discrete environmental shifts can select for reproducible genetic changes. Conspecific individuals are an important feature of an animal's environment, and a potential source of selective pressures. Here we show that adaptation of two Caenorhabditis species to growth at high density, a feature common to domestic environments, occurs by reproducible genetic changes to pheromone receptor genes. Chemical communication through pheromones that accumulate during high-density growth causes young nematode larvae to enter the long-lived but non-reproductive dauer stage. Two strains of Caenorhabditis elegans grown at high density have independently acquired multigenic resistance to pheromone-induced dauer formation. In each strain, resistance to the pheromone ascaroside C3 results from a deletion that disrupts the adjacent chemoreceptor genes serpentine receptor class g (srg)-36 and -37. Through misexpression experiments, we show that these genes encode redundant G-protein-coupled receptors for ascaroside C3. Multigenic resistance to dauer formation has also arisen in high-density cultures of a different nematode species, Caenorhabditis briggsae, resulting in part from deletion of an srg gene paralogous to srg-36 and srg-37. These results demonstrate rapid remodelling of the chemoreceptor repertoire as an adaptation to specific environments, and indicate that parallel changes to a common genetic substrate can affect life-history traits across species.

  10. Shifts in sensory neuron identity parallel differences in pheromone preference in the European corn borer

    Directory of Open Access Journals (Sweden)

    Fotini A Koutroumpa

    2014-10-01

    Full Text Available Pheromone communication relies on highly specific signals sent and received between members of the same species. However, how pheromone specificity is determined in moth olfactory circuits remains unknown. Here we provide the first glimpse into the mechanism that generates this specificity in Ostrinia nubilalis. In Ostrinia nubilalis it was found that a single locus causes strain-specific, diametrically opposed preferences for a 2-component pheromone blend. Previously we found pheromone preference to be correlated with the strain and hybrid-specific relative antennal response to both pheromone components. This led to the current study, in which we detail the underlying mechanism of this differential response, through chemotopically mapping of the pheromone detection circuit in the antenna. We determined that both strains and their hybrids have swapped the neuronal identity of the pheromone-sensitive neurons co-housed within a single sensillum. Furthermore, neurons that mediate behavioral antagonism surprisingly co-express up to five pheromone receptors, mirroring the concordantly broad tuning to heterospecific pheromones. This appears as possible evolutionary adaptation that could prevent cross attraction to a range of heterospecific signals, while keeping the pheromone detection system to its simplest tripartite setup.

  11. Controlled release of insect sex pheromones from paraffin wax and emulsions.

    Science.gov (United States)

    Atterholt, C A; Delwiche, M J; Rice, R E; Krochta, J M

    1999-02-22

    Paraffin wax and aqueous paraffin emulsions can be used as controlled release carriers for insect sex pheromones for mating disruption of orchard pests. Paraffin can be applied at ambient temperature as an aqueous emulsion, adheres to tree bark or foliage, releases pheromone for an extended period of time, and will slowly erode from bark and biodegrade in soil. Pheromone emulsions can be applied with simple spray equipment. Pheromone release-rates from paraffin were measured in laboratory flow-cell experiments. Pheromone was trapped from an air stream with an adsorbent, eluted periodically, and quantified by gas chromatography. Pheromone release from paraffin was partition-controlled, providing a constant (zero-order) release rate. A typical paraffin emulsion consisted of 30% paraffin, 4% pheromone, 4% soy oil, 1% vitamin E, 2% emulsifier, and the balance water. Soy oil and vitamin E acted as volatility suppressants. A constant release of oriental fruit moth pheromone from paraffin emulsions was observed in the laboratory for more than 100 days at 27 degreesC, with release-rates ranging from 0.4 to 2 mg/day, depending on the concentration and surface area of the dried emulsion. The use of paraffin emulsions is a viable method for direct application of insect pheromones for mating disruption. Sprayable formulations can be designed to release insect pheromones to the environment at a rate necessary for insect control by mating disruption. At temperatures below 38 degreesC, zero-order release was observed. At 38 degreesC and higher, pheromone oxidation occurred. A partition-controlled release mechanism was supported by a zero-order pheromone release-rate, low air/wax partition coefficients, and pheromone solubility in paraffin.

  12. Anatomical localization and stereoisomeric composition of Tribolium castaneum aggregation pheromones

    Science.gov (United States)

    Lu, Yujie; Beeman, Richard W.; Campbell, James F.; Park, Yoonseong; Aikins, Michael J.; Mori, Kenji; Akasaka, Kazuaki; Tamogami, Shigeyuki; Phillips, Thomas W.

    2011-09-01

    We report that the abdominal epidermis and associated tissues are the predominant sources of male-produced pheromones in the red flour beetle, Tribolium castaneum and, for the first time, describe the stereoisomeric composition of the natural blend of isomers of the aggregation pheromone 4,8-dimethyldecanal (DMD) in this important pest species. Quantitative analyses via gas chromatography-mass spectrometry showed that the average amount of DMD released daily by single feeding males of T. castaneum was 878 ± 72 ng (SE). Analysis of different body parts identified the abdominal epidermis as the major source of aggregation pheromone; the thorax was a minor source, while no DMD was detectable in the head. No internal organs or obvious male-specific glands were associated with pheromone deposition. Complete separation of all four stereoisomers of DMD was achieved following oxidation to the corresponding acid, derivatization with (1 R, 2 R)- and (1 S, 2 S)-2-(anthracene-2,3-dicarboximido)cyclohexanol to diastereomeric esters, and their separation on reversed-phase high-performance liquid chromatography at -54°C. Analysis of the hexane eluate from Porapak-Q-collected volatiles from feeding males revealed the presence of all four isomers (4 R,8 R)/(4 R,8 S)/(4 S,8 R)/(4 S,8 S) at a ratio of approximately 4:4:1:1. A walking orientation bioassay in a wind tunnel with various blends of the four synthetic isomers further indicated that the attractive potency of the reconstituted natural blend of 4:4:1:1 was equivalent to that of the natural pheromone and greater than that of the 1:1 blend of (4 R,8 R)/(4 R,8 S) used in commercial lures.

  13. Brooding, reflection, and distraction: Relation to non-suicidal self-injury versus suicide attempts

    Science.gov (United States)

    Polanco-Roman, Lillian; Jurska, Justyna; Quiñones, Victoria; Miranda, Regina

    2016-01-01

    Objectives The present study examined the relation between cognitive response styles (i.e., brooding, reflection, distraction) and cognitive inflexibility in differentially predicting history of non-suicidal self-injury (NSSI) only, suicide attempt (SA) only, or both (NSSI+SA). Methods College students (N = 352) completed self-report measures of rumination, distraction, and self-harm history, a diagnostic interview, and a computerized task measuring cognitive flexibility. Results Brooding uniquely predicted SA-only history, while reflection uniquely predicted history of NSSI-only and NSSI+SA. Distraction was associated with lower odds of NSSI-only and NSSI+SA. Cognitive inflexibility was not significantly associated with self-harm history. Conclusion Cognitive vulnerabilities may help identify individuals who are at risk for self-harm and may differentiate between NSSI and SA. PMID:25517765

  14. Fungi infection in honeybee hives in regions affected by Brazilian sac brood

    Directory of Open Access Journals (Sweden)

    K.M. Keller

    2014-10-01

    Full Text Available The Brazilian Sac Brood is a disease that affects apiaries of Africanized bee hives in Brazil, thereby making them susceptible to high losses. This study investigated the pathogenicity of Africanized bee hives by the entomopathogenic fungi in a Brazilian Sac Brood endemic region. The degree of fungal contamination, presence of mycotoxins in beehive elements, and vulnerability of healthy beehives in environments subjected and not subjected to the disease were investigated. From the contaminating fungal load, species that are mycotoxin producers and pathogenic causing mortality in the bees have been isolated. The analysis of bee pollen and bee bread samples did not show the presence of the toxic pollen of Stryphnodendron (Fabaceae, which has been indicated as the causative agent of mortality in pre-pupal stage larvae. However, bee bread showed the highest correlation between substrate and fungal contamination.

  15. The relationship between hatching rate and number of embryos of the brood pouch in Littorina saxatilis

    Science.gov (United States)

    Conde-Padín, P.; Carballo, M.; Caballero, A.; Rolán-Alvarez, E.

    2008-10-01

    Littorina saxatilis is an ovoviviparous organism in which shelled embryos can be directly observed in nearly all mature females captured in the wild. This characteristic has been used a number of times as an indirect estimate for fecundity of natural populations. However, there is no experimental corroboration that the number of embryos within a female brood pouch is actually related to the rate of hatching per unit of time, a more realistic estimate of female fecundity. In order to make this corroboration we estimated the correlation between the number of embryos in the brood pouch and the hatching rate of isolated females grown in the laboratory. We also compared the hatching rates of females from two sympatric ecotypes (RB and SU) of this species, which differ significantly in the number of embryos. We found a high agreement between hatching rate and number of embryos, concluding that the latter is a good proxy for fecundity.

  16. Effects of captan on Apis mellifera brood development under field conditions in California almond orchards.

    Science.gov (United States)

    Everich, R; Schiller, C; Whitehead, J; Beavers, M; Barrett, K

    2009-02-01

    Three almond field trials were conducted during 2003 and 2004 at two locations in central (Fresno County) and northern (Yolo County) California to evaluate the potential effects of commercial applications of Captan on honey bees, Apis mellifera L. Captan was applied at 5.0 kg (AI)/ha during bloom. Hives were evaluated for hive health and brood development parameters for approximately 2 mo after application. This study showed that the application of Captan was not harmful to foraging honey bees or their brood. No treatment-related effects were noted on hive weights, dead bee deformity, number of dead bees, survival of individual larvae, weight of individual emerging adults, and other hive health parameters.

  17. Brooding, Reflection, and Distraction: Relation to Non-Suicidal Self-Injury versus Suicide Attempts.

    Science.gov (United States)

    Polanco-Roman, Lillian; Jurska, Justyna; Quiñones, Victoria; Miranda, Regina

    2015-01-01

    The present study examined the relation between cognitive response styles (i.e., brooding, reflection, distraction) and cognitive inflexibility in differentially predicting history of non-suicidal self-injury (NSSI) only, suicide attempt (SA) only, or both (NSSI + SA). College students (N = 352) completed self-report measures of rumination, distraction, and self-harm history, a diagnostic interview, and a computerized task measuring cognitive flexibility. Brooding uniquely predicted SA-only history, while reflection uniquely predicted history of NSSI-only and NSSI + SA. Distraction was associated with lower odds of NSSI-only and NSSI + SA. Cognitive inflexibility was not significantly associated with self-harm history. Cognitive vulnerabilities may help identify individuals who are at risk for self-harm and may differentiate between NSSI and SA.

  18. It is not all pheromones: No evidence that pheromones affect digging face choice during ant nest excavation.

    Science.gov (United States)

    Bruce, Andrew I

    2016-01-01

    Ants create nests of a size that is tailored to the number of individuals in a nest via a self-organized process. It is not yet clear how they accomplish this. Deposition and evaporation of pheromones at the digging face has been hypothesised by Deneubourg and Franks (1995) and Buhl et al. (2005) to be part of the nest construction process, with models being presented to support this contention. This hypothesis was tested by allowing groups of 5 Acromyrmex lundi workers to choose between two excavation sites, one that was freshly exposed to digging and one where digging had ceased an hour previously. It was expected that if pheromones played a role in stimulating digging, then ants would show a preference for digging in the "fresh" sites rather than the "aged" sites where the putative digging pheromone had decayed. No significant difference in digging activity between "fresh" and "aged" sites was detected. It is therefore likely that, while digging pheromones may play other roles in other parts of the digging system, they do not play an important role in regulation of soil excavation at the digging face.

  19. Functional characterization of a pheromone-binding protein from rice leaffolder Cnaphalocrocis medinalis in detecting pheromones and host plant volatiles.

    Science.gov (United States)

    Sun, X; Zhao, Z-F; Zeng, F-F; Zhang, A; Lu, Z-X; Wang, M-Q

    2016-12-01

    Pheromone-binding proteins (PBPs) are believed to be involved in the recognition of semiochemicals. In the present study, western blot analysis, fluorescence-binding characteristics and immunolocalization of CmedPBP4 from the rice leaffolder, Cnaphalocrocis medinalis, were investigated. Western blot analysis revealed that CmedPBP4 showed obvious antenna-specific expression patterns in female and male antenna, and made a clearly different sex-biased expression. Immunocytochemical labeling revealed that CmedPBP4 showed specific expression in the trichoid sensilla. Competitive fluorescence binding assays indicated that CmedPBP4 could selectively recognize three sex pheromone components (Z13-18:Ac, Z11-16:Al and Z13-18:OH) and eleven rice plant volatiles, including cyclohexanol, nerolidol, cedrol, dodecanal, ionone, (-)-α-cedrene, (Z)-farnesene, β-myrcene, R-(+)-limonene, (-)-limonene, and (+)-3-carene. Meanwhile the CmedPBP4 detection of sex pheromones and host odorants was pH-dependent. Our results, for the first time, provide further evidence that trichoid sensilla might be play an important role in detecting sex pheromones and host plant volatiles in the C. medinalis moth. Our systematic studies provided further detailed evidence for the function of trichoid sensilla in insect semiochemical perception.

  20. Binding interaction between a queen pheromone component HOB and pheromone binding protein ASP1 of Apis cerana.

    Science.gov (United States)

    Weng, Chen; Fu, Yuxia; Jiang, Hongtao; Zhuang, Shulin; Li, Hongliang

    2015-01-01

    The honeybee's social behavior is closely related to the critical response to pheromone, while pheromone binding proteins (PBPs) play an important role in binding and transferring those pheromones. Here we report one known PBP, antennal special protein 1(ASP1), which has high affinity with a queen mandibular pheromone component, methyl-p-hydroxybenzoate (HOB). In this study, multiple fluorescent spectra, UV absorption spectra, circular dichroism (CD) spectra and molecular docking analysis were combined to clarify the binding process. Basically, fluorescence intensity of ASP1 could be considerably quenched by HOB with an appropriate interaction distance (3.1 nm), indicating that a complex, which is more stable in lower temperature, was formed. The fact ΔH < 0, ΔS < 0, by thermodynamic analysis, indicated the van der Waals and hydrogen bond as main driving force. Moreover, synchronous fluorescence spectra and CD spectra analysis showed the change of partial hydrophilicity of ASP1 and the increase of α-helix after HOB addition. In conclusion, ASP1 can strongly and spontaneously interact with HOB. But the binding ability decreases with the rise of temperature, which may be necessary for sufficient social stability of hives. This study provides elucidation of the detailed binding mechanism and potential physicochemical basis of thermal stability to the social behavior of honeybee.

  1. Heritable variation of sex pheromone composition and the potential for evolution of resistance to pheromone-based control of the Indian meal moth, Plodia interpunctella.

    Science.gov (United States)

    Svensson, Glenn P; Ryne, Camilla; Löfstedt, Christer

    2002-07-01

    The short-term evolutionary effect of pheromone-based mating disruption on the mating ability of the Indian meal moth, Plodia interpunctella, was investigated. Three independent selection lines were established, and the mating ability of moths in plastic tents treated with high doses of pheromone and in control tents was compared for two consecutive generations. In addition, the heritability of the sex pheromone blend, measured as the ratio of two major pheromone components (Z,E)-9,12-tetradecadienyl acetate and (Z,E)-9,12-tetradecadienol, was estimated. Based on a mother-daughter regression analysis including 21 families, the heritability of the pheromone blend was 0.65 +/- 0.14, indicating a potential for evolutionary change of the character. However, no increase in mating ability of females in pheromone-treated tents or alteration of the pheromone blend was observed in any selection line when compared with control lines, indicating no or weak selection on the pheromone blend as well as other traits influencing mating ability of this species under the created mating disruption conditions. Factors contributing to the lack of selection effects are discussed.

  2. Mating Disruption of a Carpenter Moth, Cossus insularis (Lepidoptera: Cossidae) in Apple Orchards with Synthetic Sex Pheromone, and Registration of the Pheromone as an Agrochemical.

    Science.gov (United States)

    Hoshi, Hirotsuna; Takabe, Masanori; Nakamuta, Kiyoshi

    2016-07-01

    Mating disruption of the carpenter moth, Cossus insularis (Staudinger) (Lepidoptera: Cossidae), with a synthetic version of its sex pheromone, a mixture of (E)-3-tetradecenyl acetate and (Z)-3-tetradecenyl acetate, was tested for three successive years in apple (Malus domestica Borkh.) orchards. Pheromone trap catches, percentage mating of tethered females and females enclosed with males in a mating cage, and tree damage were measured in both the pheromone-treated and untreated control orchards. The attraction of male moths to pheromone traps at heights of 1.5, 3, and 5 m was strongly disrupted when the pheromone dispensers were placed at 1.5 m height. Mating of tethered females placed at 1 m was completely inhibited, and the mating of tethered females at a height of 3 m was significantly reduced by the treatment in comparison to matings in an untreated control orchard. Similarly, mating of pairs of moths enclosed in mating cages was significantly reduced by the synthetic pheromone treatment in comparison to controls. The percentage of damaged trees in the pheromone-treated orchard also decreased significantly over the course of the experiment. These results suggest that mating disruption with the synthetic sex pheromone appears promising for reducing damage caused by C. insularis in apple orchards in Japan, and a commercial mating disruption product has been developed and registered.

  3. The internal-brooding apparatus in the bryozoan genus Cauloramphus (Cheilostomata: Calloporidae) and its inferred homology to ovicells.

    Science.gov (United States)

    Ostrovsky, Andrew N; Dick, Matthew H; Mawatari, Shunsuke F

    2007-12-01

    We studied by SEM the external morphology of the ooecium in eight bryozoans of the genus Cauloramphus (Cheilostomata, Calloporidae): C. spinifer, C. variegatus, C. magnus, C. multiavicularia, C. tortilis, C. cryptoarmatus, C. niger, and C. multispinosus, and by sectioning and light microscopy the anatomy of the brooding apparatus of C. spinifer, C. cryptoarmatus, and C. niger. These species all have a brood sac, formed by invagination of the non-calcified distal body wall of the maternal zooid, located in the distal half of the maternal (egg-producing) autozooid, and a vestigial, maternally budded kenozooidal ooecium. The brood sac comprises a main chamber and a long passage (neck) opening externally independently of the introvert. The non-calcified portion of the maternal distal wall between the neck and tip of the zooidal operculum is involved in closing and opening the brood sac, and contains both musculature and a reduced sclerite that suggest homology with the ooecial vesicle of a hyperstomial ovicell. We interpret the brooding apparatus in Cauloramphus as a highly modified form of cheilostome hyperstomial ovicell, as both types share 1) a brood chamber bounded by 2) the ooecium and 3) a component of the distal wall of the maternal zooid. We discuss Cauloramphus as a hypothetical penultimate stage in ovicell reduction in calloporid bryozoans. We suggest that the internal-brooding genus Gontarella, of uncertain taxonomic affinities, is actually a calloporid and represents the ultimate stage in which no trace of the ooecium remains. Internal brooding apparently evolved several times independently within the Calloporidae.

  4. Removal of drone brood from Apis mellifera (Hymenoptera: Apidae) colonies to control Varroa destructor (Acari: Varroidae) and retain adult drones.

    Science.gov (United States)

    Wantuch, Holly A; Tarpy, David R

    2009-12-01

    The parasitic mite Varroa destructor Anderson & Trueman (Acari: Varroidae) has plagued European honey bees, Apis mellifera L. (Hymenoptera: Apidae), in the Americas since its introduction in the 1980s. For many years, these mites were sufficiently controlled using synthetic acaricides. Recently, however, beekeepers have experienced increased resistance by mites to chemical pesticides, which are also known to leave residues in hive products such as wax and honey. Thus there has been increased emphasis on nonchemical integrated pest management control tactics for Varroa. Because mites preferentially reproduce in drone brood (pupal males), we developed a treatment strategy focusing on salvaging parasitized drones while removing mites from them. We removed drone brood from colonies in which there was no acaricidal application and banked them in separate "drone-brood receiving" colonies treated with pesticides to kill mites emerging with drones. We tested 20 colonies divided into three groups: 1) negative control (no mite treatment), 2) positive control (treatment with acaricides), and 3) drone-brood removal and placement into drone-brood receiving colonies. We found that drone-brood trapping significantly lowered mite numbers during the early months of the season, eliminating the need for additional control measures in the spring. However, mite levels in the drone-brood removal group increased later in the summer, suggesting that this benefit does not persist throughout the entire season. Our results suggest that this method of drone-brood trapping can be used as an element of an integrated control strategy to control varroa mites, eliminating a large portion of the Varroa population with limited chemical treatments while retaining the benefits of maintaining adult drones in the population.

  5. Brood ball-mediated transmission of microbiome members in the dung beetle, Onthophagus taurus (Coleoptera: Scarabaeidae.

    Directory of Open Access Journals (Sweden)

    Anne M Estes

    Full Text Available Insects feeding on plant sap, blood, and other nutritionally incomplete diets are typically associated with mutualistic bacteria that supplement missing nutrients. Herbivorous mammal dung contains more than 86% cellulose and lacks amino acids essential for insect development and reproduction. Yet one of the most ecologically necessary and evolutionarily successful groups of beetles, the dung beetles (Scarabaeinae feeds primarily, or exclusively, on dung. These associations suggest that dung beetles may benefit from mutualistic bacteria that provide nutrients missing from dung. The nesting behaviors of the female parent and the feeding behaviors of the larvae suggest that a microbiome could be vertically transmitted from the parental female to her offspring through the brood ball. Using sterile rearing and a combination of molecular and culture-based techniques, we examine transmission of the microbiome in the bull-headed dung beetle, Onthophagus taurus. Beetles were reared on autoclaved dung and the microbiome was characterized across development. A ~1425 bp region of the 16S rRNA identified Pseudomonadaceae, Enterobacteriaceae, and Comamonadaceae as the most common bacterial families across all life stages and populations, including cultured isolates from the 3(rd instar digestive system. Finer level phylotyping analyses based on lepA and gyrB amplicons of cultured isolates placed the isolates closest to Enterobacter cloacae, Providencia stuartii, Pusillimonas sp., Pedobacter heparinus, and Lysinibacillus sphaericus. Scanning electron micrographs of brood balls constructed from sterile dung reveals secretions and microbes only in the chamber the female prepares for the egg. The use of autoclaved dung for rearing, the presence of microbes in the brood ball and offspring, and identical 16S rRNA sequences in both parent and offspring suggests that the O. taurus female parent transmits specific microbiome members to her offspring through the brood

  6. Avian brood parasitism——a growing research area in behavioral ecology

    Institute of Scientific and Technical Information of China (English)

    Eivin; RSKAFT; Wei; LIANG; Brd; G.STOKKE

    2012-01-01

    正We are pleased to be responsible guest editors for the two special issues of Chinese Birds(Vol.3,No.4,2012 and Vol.4,No.1,2013),entitled "Avian Brood Parasitism — a Growing Research Area in Behavioral Ecology".The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in the fascinating research occurring in avian

  7. The Antarctic holothurian genus Echinopsolus Gutt, 1990 (Dendrochirotida, Cucumariidae): brood pouches, spermatozoa, spermatozeugmata and taxonomic implications.

    Science.gov (United States)

    Bohn, Jens Michael; Heß, Martin

    2014-07-29

    An examination of seven Antarctic brooding cucumariid and psolid holothurian species revealed a variety of characters all of them have in common: (1) All are gonochoric. (2) A genital papilla is present on the oral disc (permanent and digitiform in males). (3) Females brood their offspring in five anterior interradial brood pouches that are situated at the transition of body to introvert. (4) Multiple spermatozoa are always bundled to bunch-like spermato-zeugmata. (5) The spermatozoa have a fusiform head and a hollow cylinder-like mid-piece encircling the anterior end of the flagellum. This combination of characters so far is unique, and indicates a close relationship based on common origin. As a consequence, we unite all species sharing this set of synapomorphies in the genus Echinopsolus Gutt, 1990. The herewith included species are: E. acanthocola Gutt, 1990, E. acutus (Massin, 1992) comb. nov., E. charcoti (Vaney, 1906) comb. nov., E. koehleri (Vaney, 1914) comb. nov., E. mollis (Ludwig & Heding, 1935) comb. nov., E. parvipes Massin, 1992 and E. splendidus (Gutt, 1990) comb. nov.. Because the current assignment of Echinopsolus to the family Psolidae can not be retained, the genus is tranferred to the family Cucumariidae, as relationships to taxa within this family are obvious. The peculiar spermatozoa and spermato-zeugmata of all Echinopsolus species are described using light- and electron-microscopical techniques and the results are evaluated and discussed concerning their taxonomy and phylogeny. 

  8. Maternal androgens in avian brood parasites and their hosts: responses to parasitism and competition?

    Science.gov (United States)

    Hahn, Caldwell; Wingfield, John C.; Fox, David M.; Walker, Brian G.; Thomley, Jill E

    2017-01-01

    In the coevolutionary dynamic of avian brood parasites and their hosts, maternal (or transgenerational) effects have rarely been investigated. We examined the potential role of elevated yolk testosterone in eggs of the principal brood parasite in North America, the brown-headed cowbird, and three of its frequent host species. Elevated maternal androgens in eggs are a common maternal effect observed in many avian species when breeding conditions are unfavorable. These steroids accelerate embryo development, shorten incubation period, increase nestling growth rate, and enhance begging vigor, all traits that can increase the survival of offspring. We hypothesized that elevated maternal androgens in host eggs are a defense against brood parasitism. Our second hypothesis was that elevated maternal androgens in cowbird eggs are a defense against intra-specific competition. For host species, we found that elevated yolk testosterone was correlated with parasitized nests of small species, those whose nest success is most reduced by cowbird parasitism. For cowbirds, we found that elevated yolk testosterone was correlated with eggs in multiply-parasitized nests, which indicate intra-specific competition for nests due to high cowbird density. We propose experimental work to further examine the use of maternal effects by cowbirds and their hosts.

  9. Subsocial behaviour and brood adoption in mixed-species colonies of two theridiid spiders

    Science.gov (United States)

    Grinsted, Lena; Agnarsson, Ingi; Bilde, Trine

    2012-12-01

    Cooperation and group living often evolves through kin selection. However, associations between unrelated organisms, such as different species, can evolve if both parties benefit from the interaction. Group living is rare in spiders, but occurs in cooperative, permanently social spiders, as well as in territorial, colonial spiders. Mixed species spider colonies, involving closely related species, have rarely been documented. We examined social interactions in newly discovered mixed-species colonies of theridiid spiders on Bali, Indonesia. Our aim was to test the degree of intra- and interspecific tolerance, aggression and cooperation through behavioural experiments and examine the potential for adoption of foreign brood. Morphological and genetic analyses confirmed that colonies consisted of two related species Chikunia nigra (O.P. Cambridge, 1880) new combination (previously Chrysso nigra) and a yet undescribed Chikunia sp. Females defended territories and did not engage in cooperative prey capture, but interestingly, both species seemed to provide extended maternal care of young and indiscriminate care for foreign brood. Future studies may reveal whether these species adopt only intra-specific young, or also inter-specifically. We classify both Chikunia species subsocial and intra- and interspecifically colonial, and discuss the evolutionary significance of a system where one or both species may potentially benefit from mutual tolerance and brood adoption.

  10. Simultaneous spawning by female stream goby Rhinogobius sp. and the association with brood cannibalism by nesting males.

    Science.gov (United States)

    Ito, S; Iwao, H; Sakata, J; Inoue, M; Omori, K; Yanagisawa, Y

    2016-09-01

    A laboratory experiment was conducted by varying the undersurface area of nesting substratum and the number of females in an experimental tank to elucidate the determinants of the mating pattern in the stream goby, Rhinogobius sp. cross-band type. Males with larger nests tended to attract two or more females to their nest in a tank. Moreover, males spawned simultaneously with multiple females and entire brood cannibalism by males was rarely observed under a female-biased sex ratio. When males spawned with a single female with low fecundity, however, entire brood cannibalism occurred at a high frequency, suggesting that a male guarding a nest with fewer eggs consumes the brood. Therefore, spawning behaviour of females that leads to a large egg mass would decrease the risk of entire brood cannibalism. In this species, simultaneous spawning by multiple females in a nest serves as a female counter-measure against entire brood cannibalism. These results suggest that a conflict of interest between the sexes through brood cannibalism is a major determinant of simultaneous spawning.

  11. Trail pheromones: an integrative view of their role in social insect colony organization.

    Science.gov (United States)

    Czaczkes, Tomer J; Grüter, Christoph; Ratnieks, Francis L W

    2015-01-07

    Trail pheromones do more than simply guide social insect workers from point A to point B. Recent research has revealed additional ways in which they help to regulate colony foraging, often via positive and negative feedback processes that influence the exploitation of the different resources that a colony has knowledge of. Trail pheromones are often complementary or synergistic with other information sources, such as individual memory. Pheromone trails can be composed of two or more pheromones with different functions, and information may be embedded in the trail network geometry. These findings indicate remarkable sophistication in how trail pheromones are used to regulate colony-level behavior, and how trail pheromones are used and deployed at the individual level.

  12. Female Attacus atlas respond to pheromones of Antheraea polyphemus: a comparative electrophysiological and biochemical study.

    Science.gov (United States)

    Maida, R; Ziesmann, J

    2001-01-01

    Female Attacus atlas respond electrophysiologically to both of the Antheraea polyphemus pheromone components (E,Z)-6,11-hexadecadienyl acetate and (E,Z)-6,11-hexadecadienal. Moreover, they possess a pheromone-binding protein (PBP) and general odorant-binding proteins (GOBPs), as well as a pheromone-degrading sensillar esterase and aldehyde oxidase enzymes. They show no electroantennogram responses to their own gland extract. In contrast, female A. polyphemus do not respond to their own or to A. atlas pheromone. Male A. atlas do not detect any of the A. polyphemus compounds but only the conspecific female gland extracts. Both male A. atlas and female A. polyphemus possess PBP and GOBP but lack the pheromone-degrading esterases of male Antheraea. The results indicate that the two species use quite distinct classes of chemicals as pheromones. In spite of this, the N-terminal amino acid sequences of the PBPs show homology of 68%.

  13. Field trials of aggregation pheromones for the stink bugs Chlorochroa uhleri and Chlorochroa sayi (Hemiptera: Pentatomidae).

    Science.gov (United States)

    Millar, Jocelyn G; McBrien, Heather M; McElfresh, J Steven

    2010-10-01

    In field trials, adult Chlorochroa uhleri (Stål) (Heteroptera: Pentatomidae) of both sexes were caught in significant numbers in cylindrical screen traps baited with gray rubber septum lures loaded with the main component of the male-produced pheromone, methyl (E)-6-2,3-dihydrofarnesoate. Addition of the two possible minor components of the pheromone, methyl (E)-5-2,6,10-trimethyl-5,9-undecadienoate and methyl (2E,6E)-farnesoate, did not affect attraction. Combining the pheromone with different concentrations of volatiles mimicking the odors of a known host plant, alfalfa (Medicago sativa L.), had no significant effect on attraction of adult bugs, whereas combining the pheromone with the pheromones of two sympatric stink bug species, Chlorochroa sayi (Stål) and Euschistus conspersus Uhler, decreased trap captures, suggesting interference between the pheromones. Small numbers of Chlorochroa ligata (Say) adults also were attracted, but numbers caught were too low to allow statistical comparisons between lure blends. In field trials with C. sayi, all three of the male-specific pheromone compounds [methyl geranate, methyl citronellate, and methyl (E) -6-2,3-dihydrofarnesoate] were required for optimal attraction. As with C. uhleri, adults of both sexes were attracted to pheromone lures in approximately equal numbers. Because of the decreased volatility (=release rate) of methyl (E)-6-2,3-dihydrofarnesoate in comparison with the other two, lower molecular weight pheromone components, lures needed to be loaded with a disproportionately high amount of methyl (E)-6-2,3-dihydrofarnesoate to obtain the best trap catch. There was no indication that the pheromone components of C. uhleri or E. conspersus interfered with the attractiveness of the C. sayi pheromone in lures containing a blend of all three pheromones.

  14. Mating disruption of Lobesia botrana (Lepidoptera: Tortricidae): effect of pheromone formulations and concentrations.

    Science.gov (United States)

    Gordon, Dvora; Zahavi, Tirtza; Anshelevich, Leonid; Harel, Miriam; Ovadia, Shmulik; Dunkelblum, Ezra; Harari, Ally Rachel

    2005-02-01

    The reluctance of Israeli vine growers to adopt the mating disruption technique to control the moth Lobesia botrana Den. & Schiff. has been attributed to the high cost of this method compared with that of traditional insecticide control. In this study, we tested the possibility of reducing the cost, first by testing different pheromone formulations (and thus open the market for competition) and second by reducing the pheromone concentration used in vineyards. Comparisons were made between two pheromone formulations--Shin-Etsu (Tokyo, Japan) at 165 g/ha and Concep (Sutera, Bend, OR) at 150 g/ha--and between two concentrations of Shin-Etsu, 165 and 110 g/ha. Pheromone dispensers were placed at the onset of the second moth generation. Comparison of the numbers of clusters infested with eggs and larvae of L. botrana showed no significant differences in the performance, either between the two formulations, or between the two tested concentrations. The results suggest that 1) the two formulations are equally effective, and 2) a low pheromone concentration is sufficient to maintain good control of small populations of L. botrana. However, when the population is high, pest control efficacy is not improved by increasing the pheromone concentration. Therefore, in the interest of reducing the relatively high cost of mating disruption, we emphasize that increasing the pheromone concentration does not provide improved control of high populations of L. botrana. The cost of mating disruption can be diminished by reducing the applied pheromone concentration and by using the least expensive pheromone formulations

  15. REDUCING THE THREAT TO CONTROL INVASIVE SIGNAL CRAYFISH REDUCING: THE POTENTIAL USE OF PHEROMONES

    Directory of Open Access Journals (Sweden)

    STEBBING P. D.

    2003-04-01

    Full Text Available The need for an effective method of controlling invasive species of crayfish is of utmost importance given the plight of Europe’s native crayfish species. Many techniques have been applied to the growing problem with little success. Pheromones have been used to control terrestrial insect pests for a number of years with many success stories. The concept of applying pheromone control methods to the aquatic environment is by no means new, but has not been previously developed. This paper discusses the preliminary results from field trials testing traps baited with Pacifastacus leniusculus pheromones, and the potential application of the pheromones in controlling P. leniusculus populations.

  16. Functional specificity of sex pheromone receptors in the cotton bollworm Helicoverpa armigera.

    Directory of Open Access Journals (Sweden)

    Yang Liu

    Full Text Available Male moths can accurately perceive the sex pheromone emitted from conspecific females by their highly accurate and specific olfactory sensory system. Pheromone receptors are of special importance in moth pheromone reception because of their central role in chemosensory signal transduction processes that occur in olfactory receptor neurons in the male antennae. There are a number of pheromone receptor genes have been cloned, however, only a few have been functionally characterized. Here we cloned six full-length pheromone receptor genes from Helicoverpa armigera male antennae. Real-time PCR showing all genes exhibited male-biased expression in adult antennae. Functional analyses of the six pheromone receptor genes were then conducted in the heterologous expression system of Xenopus oocytes. HarmOR13 was found to be a specific receptor for the major sex pheromone component Z11-16:Ald. HarmOR6 was equally tuned to both of Z9-16: Ald and Z9-14: Ald. HarmOR16 was sensitively tuned to Z11-16: OH. HarmOR11, HarmOR14 and HarmOR15 failed to respond to the tested candidate pheromone compounds. Our experiments elucidated the functions of some pheromone receptor genes of H. armigera. These advances may provide remarkable evidence for intraspecific mating choice and speciation extension in moths at molecular level.

  17. Modeling the suppression of sea lamprey populations by use of the male sex pheromone

    Science.gov (United States)

    Klassen, Waldemar; Adams, Jean V.; Twohey, Michael B.

    2005-01-01

    The suppression of sea lamprey populations, Petromyzon marinus (Linnaeus), was modeled using four different applications of the male sex pheromone: (1) pheromone-baited traps that remove females from the spawning population, (2) pheromone-baited decoys that exhaust females before they are able to spawn, (3) pheromone-enhanced sterile males that increase the proportion of non-fertile matings, and (4) camouflaging of the pheromone emitted by calling males to make it difficult for females to find a mate. The models indicated that thousands of traps or hundreds of thousands of decoys would be required to suppress a population of 100,000 animals. The potential efficacy of pheromone camouflages is largely unknown, and additional research is required to estimate how much pheromone is needed to camouflage the pheromone plumes of calling males. Pheromone-enhanced sterile males appear to be a promising application in the Great Lakes. Using this technique for three generations each of ca. 7 years duration could reduce sea lamprey populations by 90% for Lakes Huron and Ontario and by 98% for Lake Michigan, based on current trapping operations that capture 20 to 30% of the population each year.

  18. Genetic evidence for the coexistence of pheromone perception and full trichromatic vision in howler monkeys.

    Science.gov (United States)

    Webb, David M; Cortés-Ortiz, Liliana; Zhang, Jianzhi

    2004-04-01

    Vertebrate pheromones are water-soluble chemicals perceived mainly by the vomeronasal organ (VNO) for intraspecific communications. Humans, apes, and Old World (OW) monkeys lack functional genes responsible for the pheromone signal transduction and are generally insensitive to vomeronasal pheromones. It has been hypothesized that the evolutionary deterioration of pheromone sensitivity occurred because pheromone communication became redundant after the emergence of full trichromatic color vision via the duplication of the X-chromosome-linked red/green opsin gene in the common ancestor of hominoids and OW monkeys. Interestingly, full trichromacy also evolved in the New World (NW) howler monkeys via an independent duplication of the same gene. Here we sequenced from three species of howler monkeys an essential component of the VNO pheromone transduction pathway, the gene encoding the ion channel TRP2. In contrast to those of hominoids and OW monkeys, the howler TRP2 sequences have none of the characteristics of pseudogenes. This and other observations indicate that howler monkeys have maintained both their systems of pheromone communication and full trichromatic vision, suggesting that the presence of full trichromacy alone does not lead to the loss of pheromone communication. We suggest that the ecological differences between OW and NW primates, particularly in habitat selection, may have also affected the evolution of pheromone perception.

  19. Stingless bees (Scaptotrigona pectoralis) learn foreign trail pheromones and use them to find food.

    Science.gov (United States)

    Reichle, Christian; Aguilar, Ingrid; Ayasse, Manfred; Jarau, Stefan

    2011-03-01

    Foragers of several species of stingless bees (Hymenoptera, Apidae and Meliponini) deposit pheromone marks in the vegetation to guide nestmates to new food sources. These pheromones are produced in the labial glands and are nest and species specific. Thus, an important question is how recruited foragers recognize their nestmates' pheromone in the field. We tested whether naïve workers learn a specific trail pheromone composition while being recruited by nestmates inside the hive in the species Scaptotrigona pectoralis. We installed artificial scent trails branching off from trails deposited by recruiting foragers and registered whether newly recruited bees follow these trails. The artificial trails were baited with trail pheromones of workers collected from foreign S. pectoralis colonies. When the same foreign trail pheromone was presented inside the experimental hives while recruitment took place a significant higher number of bees followed the artificial trails than in experiments without intranidal presentation. Our results demonstrate that recruits of S. pectoralis can learn the composition of specific trail pheromone bouquets inside the nest and subsequently follow this pheromone in the field. We, therefore, suggest that trail pheromone recognition in S. pectoralis is based on a flexible learning process rather than being a genetically fixed behaviour.

  20. Specificity of the TraA-DNA interaction in the regulation of the pPD1-encoded sex pheromone response in Enterococcus faecalis.

    Science.gov (United States)

    Folli, Claudia; Mangiarotti, Laura; Folloni, Silvia; Alfieri, Beatrice; Gobbo, Marina; Berni, Rodolfo; Rivetti, Claudio

    2008-07-25

    The Enterococcus faecalis conjugative plasmid pPD1 encodes proteins responsible for the mating response to the sex pheromone cPD1 secreted by a recipient cell. This response involves the respectively negative and positive determinants traA and traE, the pheromone-inhibitor determinant ipd and structural genes participating in the conjugation process. TraA is capable of binding to key sites within the regulatory gene cluster. The binding of TraA to cognate sites is modulated by the pheromone (cPD1) and the pheromone-inhibitor (iPD1) peptides. Using atomic force microscopy and classic biochemical techniques, we mapped and characterized the TraA-DNA interactions within the pPD1 regulatory gene cluster and the role of TraA in the transcription regulation of the sex pheromone response. A previous report showed that TraA binds to three adjacent sites (tab1, tab2 and tab3) located upstream of the ipd promoter region. Here, we provide direct evidence for such interactions and show that TraA alone or in the presence of iPD1 inhibits ipd transcription by preferentially binding to tab1, whereas in the presence of saturating cPD1, the overall binding to the tab sites decreases, TraA preferentially binds to tab3 and the ipd repression is relieved. Moreover, TraA alone or in the presence of iPD1 binds to two non-adjacent sites within the ipd terminators T1 and T2, an interaction that is also relieved in the presence of cPD1. The binding of TraA to the termination region of ipd may play an important role in controlling traE and traF expression via a transcriptional read-through mechanism already postulated for the pAD1 plasmid. TraA may also regulate its own expression by binding to a site in the proximity of the traA promoter, which has been relocated 200 bp downstream of the ipd gene. A model for the TraA-mediated regulation of the pPD1-encoded sex pheromone response is presented.

  1. Family Competition Pheromone Genetic Algorithm for Comparative Genome Assembly

    Institute of Scientific and Technical Information of China (English)

    Chien-Hao Su; Chien-Shun Chiou; Jung-Che Kuo; Pei-Jen Wang; Cheng-Yan Kao; Hsueh-Ting Chu

    2014-01-01

    Genome assembly is a prerequisite step for analyzing next generation sequencing data and also far from being solved. Many assembly tools have been proposed and used extensively. Majority of them aim to assemble sequencing reads into contigs; however, we focus on the assembly of contigs into scaffolds in this paper. This is called scaffolding, which estimates the relative order of the contigs as well as the size of the gaps between these contigs. Pheromone trail-based genetic algorithm (PGA) was previously proposed and had decent performance according to their paper. From our previous study, we found that family competition mechanism in genetic algorithm is able to further improve the results. Therefore, we propose family competition pheromone genetic algorithm (FCPGA) and demonstrate the improvement over PGA.

  2. Exposure to female fertility pheromones influences men's drinking.

    Science.gov (United States)

    Tan, Robin; Goldman, Mark S

    2015-06-01

    Research has shown that humans consciously use alcohol to encourage sexual activity. In the current study, we investigated whether decision making about alcohol use and sex can be cued outside of awareness by recently revealed sexual signaling mechanisms. Specifically, we examined if males exposed without their knowledge to pheromones emitted by fertile females would increase their alcohol consumption, presumably via neurobehavioral information pathways that link alcohol to sex and mating. We found that men who smelled a T-shirt worn by a fertile female drank significantly more (nonalcoholic) beer, and exhibited significantly greater approach behavior toward female cues, than those who smelled a T-shirt worn by a nonfertile female. These findings reveal previously unknown influences on human alcohol consumption, augment the research base for pheromone cuing of sexual behavior in humans, and raise the possibility that other, as yet unknown, pathways of behavioral influence may be operating hidden from view.

  3. Isolation and structural characterization of two water-borne pheromones from Euplotes crassus, a ciliate commonly known to carry membrane-bound pheromones.

    Science.gov (United States)

    Alimenti, Claudio; Vallesi, Adriana; Federici, Sergio; di Giuseppe, Graziano; Fernando, Dini; Carratore, Vitale; Luporini, Pierangelo

    2011-01-01

    Ciliates comprise species synthesizing water-diffusible mating type factors or pheromones and species synthesizing insoluble, cell membrane-bound pheromones. Euplotes crassus has traditionally been placed in the latter group. In contrast with this notion, we found that E. crassus is a constitutive pheromone-secreting ciliate, like other Euplotes species. From cell-free filtrate preparations of the E. crassus strain L-2D, we isolated two distinct pheromones, designated as Ec-α and Ec-1, and determined their complete amino acid sequences by combined chemical and genetic approaches. The Ec-α pheromone sequence extends for 56 amino acid residues with six cysteines and shows a molecular mass of 6,183 Da, while the Ec-1 pheromone sequence extends for 45 amino acid residues with 10 cysteines and shows a molecular mass of 4,840 Da. Marked structural differences distinguish the full-length Ec-α and Ec-1 coding sequences, which have been cloned and characterized from the transcriptionally active macronuclear genome. They were taken as clear indication that the Ec-α and Ec-1 pheromones are specified by genes that are not allelic, but likely derived from a duplicated genetic locus of the transcriptionally silent micronuclear genome.

  4. Of pheromones and kairomones: what receptors mediate innate emotional responses?

    Science.gov (United States)

    Fortes-Marco, Lluis; Lanuza, Enrique; Martinez-Garcia, Fernando

    2013-09-01

    Some chemicals elicit innate emotionally laden behavioral responses. Pheromones mediate sexual attraction, parental care or agonistic confrontation, whereas predators' kairomones elicit defensive behaviors in their preys. This essay explores the hypothesis that the detection of these semiochemicals relies on highly specific olfactory and/or vomeronasal receptors. The V1R, V2R, and formyl-peptide vomeronasal receptors bind their ligands in highly specific and sensitive way, thus being good candidates for pheromone- or kairomone-detectors (e.g., secreted and excreted proteins, peptides and lipophilic volatiles). The olfactory epithelium also expresses specific receptors, for example trace amine-associated receptors (TAAR) and guanylyl cyclase receptors (GC-D and other types), some of which bind kairomones and putative pheromones. However, most of the olfactory neurons express canonical olfactory receptors (ORs) that bind many ligands with different affinity, being not suitable for mediating responses to pheromones and kairomones. In this respect, trimethylthiazoline (TMT) is considered a fox-derived kairomone for mice and rats, but it seems to be detected by canonical ORs. Therefore, we have reassessed the kairomonal nature of TMT by analyzing the behavioral responses of outbred (CD1) and inbred mice (C57BL/J6) to TMT. Our results confirm that both mouse strains avoid TMT, which increases immobility in C57BL/J6, but not CD1 mice. However, mice of both strains sniff at TMT throughout the test and show no trace of TMT-induced contextual conditioning (immobility or avoidance). This suggests that TMT is not a kairomone but, similar to a loud noise, in high concentrations it induces aversion and stress as unspecific responses to a strong olfactory stimulation.

  5. A Putative Human Pheromone, Androstadienone, Increases Cooperation between Men

    OpenAIRE

    Paavo Huoviala; Rantala, Markus J.

    2013-01-01

    Androstadienone, a component of male sweat, has been suggested to function as a human pheromone, an airborne chemical signal causing specific responses in conspecifics. In earlier studies androstadienone has been reported to increase attraction, affect subjects' mood, cortisol levels and activate brain areas linked to social cognition, among other effects. However, the existing psychological evidence is still relatively scarce, especially regarding androstadienone's effects on male behaviour....

  6. Pheromonal divergence between two strains of Spodoptera frugiperda.

    Science.gov (United States)

    Unbehend, Melanie; Hänniger, Sabine; Meagher, Robert L; Heckel, David G; Groot, Astrid T

    2013-03-01

    Spodoptera frugiperda consists of two genetically and behaviorally different strains, the corn- and the rice-strain, which seem to be in the process of sympatric speciation. We investigated the role of strain-specific sexual communication as a prezygotic mating barrier between both strains by analyzing strain-specific variation in female pheromone composition of laboratory and field strains, and also male attraction in wind tunnel and field experiments. Laboratory-reared and field-collected females from Florida exhibited strain-specific differences in their relative amount of (Z)-7-dodecenyl acetate (Z7-12:OAc) and (Z)-9-dodecenyl acetate (Z9-12:OAc). In wind tunnel assays, we did not find strain-specific attraction of males to females. However, in field experiments in Florida, we observed some differential attraction to synthetic pheromone blends. In a corn field, the corn-strain blend attracted more males of both strains than the rice-strain blend, but both blends were equally attractive in a grass field. Thus, habitat-specific volatiles seemed to influence male attraction to pheromones. In dose-response experiments, corn-strain males were more attracted to 2 % Z7-12:OAc than other doses tested, while rice-strain males were attracted to a broader range of Z7-12:OAc (2-10 %). The attraction of corn-strain males to the lowest dose of Z7-12:OAc corresponds to the production of this compound by females; corn-strain females produced significantly smaller amounts of Z7-12:OAc than rice-strain females. Although corn-strain individuals are more restricted in their production of and response to pheromones than rice-strain individuals, it seems that differences in sexual communication between corn- and rice-strain individuals are not strong enough to cause assortative mating.

  7. Exposure to Female Fertility Pheromones Influences Men’s Drinking

    OpenAIRE

    2015-01-01

    Research shows that humans consciously use alcohol to encourage sexual activity. The current study investigated whether decision-making about alcohol use and sex can be cued outside of awareness by recently revealed sexual signaling mechanisms. Specifically, we examined if males exposed without their knowledge to pheromones emitted by fertile females would increase their alcohol consumption, presumably via neurobehavioral information pathways that link alcohol to sex and mating. We found that...

  8. Brain response to putative pheromones in lesbian women

    OpenAIRE

    2006-01-01

    The progesterone derivative 4,16-androstadien-3-one (AND) and the estrogen-like steroid estra-1,3,5(10),16-tetraen-3-ol (EST) are candidate compounds for human pheromones. In previous positron emission tomography studies, we found that smelling AND and EST activated regions primarily incorporating the sexually dimorphic nuclei of the anterior hypothalamus, that this activation was differentiated with respect to sex and compound, and that homosexual men processed AND congruently with heterosex...

  9. Pheromones and their role as aphrodisiacs: A review

    OpenAIRE

    2013-01-01

    Since the beginning of the human existence on the earth reproductive biology remained a main concern of research because of its importance. It is widely recognized and demonstrated that odors play an important role in mammalian reproduction. A large number of studies have been carried out in humans, in order to investigate possible pheromones, their properties, mechanism of action, and possible receptors for their action. Till now scientific studies indicated that humans use olfactory communi...

  10. Sex-specific mating pheromones in the nematode Panagrellus redivivus

    OpenAIRE

    Choe, Andrea; Chuman, Tatsuji; von Reuss, Stephan H.; Dossey, Aaron T.; Yim, Joshua J.; Ajredini, Ramadan; Kolawa, Adam A.; Kaplan, Fatma; Alborn, Hans T.; Teal, Peter E. A.; Schroeder, Frank C.; Paul W. Sternberg; EDISON, ARTHUR S.

    2012-01-01

    Nematodes use an extensive chemical language based on glycosides of the dideoxysugar ascarylose for developmental regulation (dauer formation), male sex attraction, aggregation, and dispersal. However, no examples of a female- or hermaphrodite-specific sex attractant have been identified to date. In this study, we investigated the pheromone system of the gonochoristic sour paste nematode Panagrellus redivivus, which produces sex-specific attractants of the opposite sex. Activity-guided fracti...

  11. Modeling Yeast Cell Polarization Induced by Pheromone Gradients

    Science.gov (United States)

    Yi, Tau-Mu; Chen, Shanqin; Chou, Ching-Shan; Nie, Qing

    2007-07-01

    Yeast cells respond to spatial gradients of mating pheromones by polarizing and projecting up the gradient toward the source. It is thought that they employ a spatial sensing mechanism in which the cell compares the concentration of pheromone at different points on the cell surface and determines the maximum point, where the projection forms. Here we constructed the first spatial mathematical model of the yeast pheromone response that describes the dynamics of the heterotrimeric and Cdc42p G-protein cycles, which are linked in a cascade. Two key performance objectives of this system are (1) amplification—converting a shallow external gradient of ligand to a steep internal gradient of protein components and (2) tracking—following changes in gradient direction. We used simulations to investigate amplification mechanisms that allow tracking. We identified specific strategies for regulating the spatial dynamics of the protein components (i.e. their changing location in the cell) that would enable the cell to achieve both objectives.

  12. Flexible origin of hydrocarbon/pheromone precursors in Drosophila melanogaster.

    Science.gov (United States)

    Wicker-Thomas, Claude; Garrido, Damien; Bontonou, Gwénaëlle; Napal, Laura; Mazuras, Nicolas; Denis, Béatrice; Rubin, Thomas; Parvy, Jean-Philippe; Montagne, Jacques

    2015-11-01

    In terrestrial insects, cuticular hydrocarbons (CHCs) provide protection from desiccation. Specific CHCs can also act as pheromones, which are important for successful mating. Oenocytes are abdominal cells thought to act as specialized units for CHC biogenesis that consists of long-chain fatty acid (LCFA) synthesis, optional desaturation(s), elongation to very long-chain fatty acids (VLCFAs), and removal of the carboxyl group. By investigating CHC biogenesis in Drosophila melanogaster, we showed that VLCFA synthesis takes place only within the oenocytes. Conversely, several pathways, which may compensate for one another, can feed the oenocyte pool of LCFAs, suggesting that this step is a critical node for regulating CHC synthesis. Importantly, flies deficient in LCFA synthesis sacrificed their triacylglycerol stores while maintaining some CHC production. Moreover, pheromone production was lower in adult flies that emerged from larvae that were fed excess dietary lipids, and their mating success was lower. Further, we showed that pheromone production in the oenocytes depends on lipid metabolism in the fat tissue and that fatty acid transport protein, a bipartite acyl-CoA synthase (ACS)/FA transporter, likely acts through its ACS domain in the oenocyte pathway of CHC biogenesis. Our study highlights the importance of environmental and physiological inputs in regulating LCFA synthesis to eventually control sexual communication in a polyphagous animal.

  13. Genetic control of conventional and pheromone-stimulated biofilm formation in Candida albicans.

    Science.gov (United States)

    Lin, Ching-Hsuan; Kabrawala, Shail; Fox, Emily P; Nobile, Clarissa J; Johnson, Alexander D; Bennett, Richard J

    2013-01-01

    Candida albicans can stochastically switch between two phenotypes, white and opaque. Opaque cells are the sexually competent form of C. albicans and therefore undergo efficient polarized growth and mating in the presence of pheromone. In contrast, white cells cannot mate, but are induced - under a specialized set of conditions - to form biofilms in response to pheromone. In this work, we compare the genetic regulation of such "pheromone-stimulated" biofilms with that of "conventional" C. albicans biofilms. In particular, we examined a network of six transcriptional regulators (Bcr1, Brg1, Efg1, Tec1, Ndt80, and Rob1) that mediate conventional biofilm formation for their potential roles in pheromone-stimulated biofilm formation. We show that four of the six transcription factors (Bcr1, Brg1, Rob1, and Tec1) promote formation of both conventional and pheromone-stimulated biofilms, indicating they play general roles in cell cohesion and biofilm development. In addition, we identify the master transcriptional regulator of pheromone-stimulated biofilms as C. albicans Cph1, ortholog of Saccharomyces cerevisiae Ste12. Cph1 regulates mating in C. albicans opaque cells, and here we show that Cph1 is also essential for pheromone-stimulated biofilm formation in white cells. In contrast, Cph1 is dispensable for the formation of conventional biofilms. The regulation of pheromone- stimulated biofilm formation was further investigated by transcriptional profiling and genetic analyses. These studies identified 196 genes that are induced by pheromone signaling during biofilm formation. One of these genes, HGC1, is shown to be required for both conventional and pheromone-stimulated biofilm formation. Taken together, these observations compare and contrast the regulation of conventional and pheromone-stimulated biofilm formation in C. albicans, and demonstrate that Cph1 is required for the latter, but not the former.

  14. Pheromonal and behavioral cues trigger male-to-female aggression in Drosophila.

    Science.gov (United States)

    Fernández, María de la Paz; Chan, Yick-Bun; Yew, Joanne Y; Billeter, Jean-Christophe; Dreisewerd, Klaus; Levine, Joel D; Kravitz, Edward A

    2010-11-23

    Appropriate displays of aggression rely on the ability to recognize potential competitors. As in most species, Drosophila males fight with other males and do not attack females. In insects, sex recognition is strongly dependent on chemosensory communication, mediated by cuticular hydrocarbons acting as pheromones. While the roles of chemical and other sensory cues in stimulating male to female courtship have been well characterized in Drosophila, the signals that elicit aggression remain unclear. Here we show that when female pheromones or behavior are masculinized, males recognize females as competitors and switch from courtship to aggression. To masculinize female pheromones, a transgene carrying dsRNA for the sex determination factor transformer (traIR) was targeted to the pheromone producing cells, the oenocytes. Shortly after copulation males attacked these females, indicating that pheromonal cues can override other sensory cues. Surprisingly, masculinization of female behavior by targeting traIR to the nervous system in an otherwise normal female also was sufficient to trigger male aggression. Simultaneous masculinization of both pheromones and behavior induced a complete switch in the normal male response to a female. Control males now fought rather than copulated with these females. In a reciprocal experiment, feminization of the oenocytes and nervous system in males by expression of transformer (traF) elicited high levels of courtship and little or no aggression from control males. Finally, when confronted with flies devoid of pheromones, control males attacked male but not female opponents, suggesting that aggression is not a default behavior in the absence of pheromonal cues. Thus, our results show that masculinization of either pheromones or behavior in females is sufficient to trigger male-to-female aggression. Moreover, by manipulating both the pheromonal profile and the fighting patterns displayed by the opponent, male behavioral responses towards

  15. Pheromonal and behavioral cues trigger male-to-female aggression in Drosophila.

    Directory of Open Access Journals (Sweden)

    María de la Paz Fernández

    Full Text Available Appropriate displays of aggression rely on the ability to recognize potential competitors. As in most species, Drosophila males fight with other males and do not attack females. In insects, sex recognition is strongly dependent on chemosensory communication, mediated by cuticular hydrocarbons acting as pheromones. While the roles of chemical and other sensory cues in stimulating male to female courtship have been well characterized in Drosophila, the signals that elicit aggression remain unclear. Here we show that when female pheromones or behavior are masculinized, males recognize females as competitors and switch from courtship to aggression. To masculinize female pheromones, a transgene carrying dsRNA for the sex determination factor transformer (traIR was targeted to the pheromone producing cells, the oenocytes. Shortly after copulation males attacked these females, indicating that pheromonal cues can override other sensory cues. Surprisingly, masculinization of female behavior by targeting traIR to the nervous system in an otherwise normal female also was sufficient to trigger male aggression. Simultaneous masculinization of both pheromones and behavior induced a complete switch in the normal male response to a female. Control males now fought rather than copulated with these females. In a reciprocal experiment, feminization of the oenocytes and nervous system in males by expression of transformer (traF elicited high levels of courtship and little or no aggression from control males. Finally, when confronted with flies devoid of pheromones, control males attacked male but not female opponents, suggesting that aggression is not a default behavior in the absence of pheromonal cues. Thus, our results show that masculinization of either pheromones or behavior in females is sufficient to trigger male-to-female aggression. Moreover, by manipulating both the pheromonal profile and the fighting patterns displayed by the opponent, male behavioral

  16. Effects of two pheromone trap densities against banana weevil Cosmopolites sordidus, populations and their impact on plant damage in Uganda

    NARCIS (Netherlands)

    Tinzaara, W.; Gold, C.S.; Kagezi, G.H.; Dicke, M.; Huis, van A.; Nankinga, C.; Tushemereirwe, W.; Ragama, P.E.

    2005-01-01

    An on-farm study to evaluate the effect of pheromone trap density on the population of the banana weevil, Cosmopolites sordidus (Germar) (Col., Curculionidae) was conducted in Masaka district, Uganda. The pheromone used was Cosmolure+, a commercially available weevil aggregation pheromone. Forty-two

  17. Translocation of threatened New Zealand falcons to vineyards increases nest attendance, brooding and feeding rates.

    Directory of Open Access Journals (Sweden)

    Sara M Kross

    Full Text Available Anthropogenic landscapes can be rich in resources, and may in some cases provide potential habitat for species whose natural habitat has declined. We used remote videography to assess whether reintroducing individuals of the threatened New Zealand falcon Falco novaeseelandiae into a highly modified agricultural habitat affected the feeding rates of breeding falcons or related breeding behavior such as nest attendance and brooding rates. Over 2,800 recording hours of footage were used to compare the behavior of falcons living in six natural nests (in unmanaged, hilly terrain between 4 km and 20 km from the nearest vineyard, with that of four breeding falcon pairs that had been transported into vineyards and nested within 500 m of the nearest vineyard. Falcons in vineyard nests had higher feeding rates, higher nest attendance, and higher brooding rates. As chick age increased, parents in vineyard nests fed chicks a greater amount of total prey and larger prey items on average than did parents in hill nests. Parents with larger broods brought in larger prey items and a greater total sum of prey biomass. Nevertheless, chicks in nests containing siblings received less daily biomass per individual than single chicks. Some of these results can be attributed to the supplementary feeding of falcons in vineyards. However, even after removing supplementary food from our analysis, falcons in vineyards still fed larger prey items to chicks than did parents in hill nests, suggesting that the anthropogenic habitat may be a viable source of quality food. Although agricultural regions globally are rarely associated with raptor conservation, these results suggest that translocating New Zealand falcons into vineyards has potential for the conservation of this species.

  18. Brood surveys and hunter observations used to predict gobbling activity wild turkeys in Mississippi

    Science.gov (United States)

    Palumbo, Matthew D.; Vilella, Francisco; Strickland, Bronson K.; Wang, Guiming; Godwin, Dave

    2014-01-01

    The Mississippi Department of Wildlife, Fisheries, and Parks utilize data from turkey hunter observations and brood surveys from across the state to manage wild turkey Meleagris gallopavo populations. Since 1995, hunters have collected gobbling and jake observation data, while the Mississippi Department of Wildlife, Fisheries, and Parks' personnel and cooperating wildlife managers of several natural resource agencies throughout the state have collected brood survey data. Both sources of data serve to forecast poult recruitment and gobbling activity. The objective of this study was to evaluate if these data can serve as a viable predictor of gobbling activity. We used three mixed models to investigate the relationship between the number of jakes observed per hour of hunting 1 y prior and the total number of poults per hens 2 y prior (model 1), number of gobblers heard per hour of hunting and the number of jakes observed per hour of hunting 1 y prior (model 2), the number of gobblers heard per hour of hunting and the total number poults per total hens observed 2 y prior (model 3) using data from 1995 to 2008 among five wild turkey management regions encompassing the state. We incorporated region as a random effect to account for spatial variation. We found the number of jakes observed per hour of hunting 1 y prior correlated with the total number of poults per total hens observed 2 y prior. We also found the number of gobblers heard per hour of hunting correlated with the number of jakes observed per hour of hunting 1 y prior. Additionally, we found that the total poults per total hens observed 2 y prior was correlated to the number of gobblers heard per hour of hunting. Our results show promise for using indices of gobbling activity, jake observations, and brood surveys to estimate gobbling activity.

  19. Drosophila CheB proteins involved in gustatory detection of pheromones are related to a human neurodegeneration factor.

    Science.gov (United States)

    Pikielny, Claudio W

    2010-01-01

    The Drosophila CheBs proteins are expressed in a variety of sexually dimorphic subsets of taste hairs, some of which have been directly implicated in pheromone detection. Their remarkable collection of expression patterns suggests that CheBs have specialized roles in gustatory detection of pheromones. Indeed, mutations in the CheB42a gene specifically alter male response to female-specific cuticular hydrocarbons. Furthermore, CheBs belong to the large ML (MD-2-like) superfamily of lipid-binding proteins and share amino acids with an essential role in the function of human GM2-activator protein (GM2-AP), a protein whose absence results in neurodegeneration and death. As GM2-AP binds specifically to the GM2 ganglioside, we have proposed that CheB42a and other CheBs function by interacting directly with the lipid-like cuticular hydrocarbons of Drosophila melanogaster and modulating their detection by transmembrane receptors. Here I review the current knowledge of the CheB family and discuss possible models for their function.

  20. Development rate and brood production in haplo- and pleometrotic colonies of Oecophylla smaragdina

    DEFF Research Database (Denmark)

    Offenberg, Joachim; Peng, Renkang; Nielsen, Mogens Gissel

    2012-01-01

    until the first worker emerges may shorten. For territorial species and species that rob brood from neighbouring colonies, a faster production of more workers may improve the chance of surviving intraspecific competition. In this study, the time from the nuptial flight to the emergence of the first...... with development time, showing that earlier development of the first worker increased queen fecundity. These results indicate that pleometrotic O. smaragdina colonies are competitively superior to haplometrotic colonies as they produce more workers faster and shorten the claustral phase, leading to increased queen...

  1. Do brooding and polygamy behaviors exist on Cretaceous oviraptoroid dinosaurs of China: a paleobiological perspective

    Science.gov (United States)

    Yang, T.-R.; Cheng, Y.-N.; Yang, K.-M.

    2012-04-01

    Brooding, parental care, and polygamy represent three different stages in bird's reproduction. The oringin of these behaviors is still in debate. Several samples excavated from China strengthen the phylogenetic relationship between birds and dinosaurs, for example, feathered dinosaurs, paired-eggs in pelvic region of an oviraptorid dinosaur, and small theropod fossils. Previous studies in past two decades, including an oviraptor sitting on a clutch and comparison of the ratio of clutch-volume to adult-body-size between Aves and Mesozoic dinosaurs, proposed that these behaviors had appeared on some Cretaceous theropods (e.g., oviraptor and troodon). These researches also indicate the possibility of endothermy and male care first. In conclusion, this reproduction strategy might support females having more remnant energy to build a larger clutch contributed eggs from multiple females, and brooded by males only. From our cluster analysis through paleoecological perspectives, the eggs in Cretaceous oviraptor's nest should not be corporately laid by multiple females. In morphological observation, the fossilized clutches from Ganzhou, Jiangxi, Mainland China, are 2-layered interbeded with matrix of reddish-brown siltstone or clays. The inner-layer eggs are hampered from directly contacting with adult dinosaurs body. Furthermore, the blunt ends of the eggs point to the center, and incline away forming a mound-shape nest, which is completely different from those of precocial and male-caring megapode. The ornamentation of eggshell surface and microstructures from thin sections of eggs from oviraptors and ostrich (Struthioniformes) are totally different. Comparison of thickness in different part of oviraptor's egg also reveal possible physiological structure in the egg and ecological behaviors. The detailed comparison implies that the Mesozoic oviraptoroid dinosaurs hold absolutely different incubation and caring behaviors from extant birds. We propose an alternative

  2. Subsocial behaviour and brood adoption in mixed-species colonies of two theridiid spiders

    DEFF Research Database (Denmark)

    Grinsted, Lena; Agnarsson, Ingi; Bilde, Trine

    2012-01-01

    Cooperation and group living often evolves through kin selection. However, associations between unrelated organisms, such as different species, can evolve if both parties benefit from the interaction. Group living is rare in spiders, but occurs in cooperative, permanently social spiders, as well......, aggression and cooperation through behavioural experiments and examine the potential for adoption of foreign brood. Morphological and genetic analyses confirmed that colonies consisted of two related species Chikunia nigra (O.P. Cambridge, 1880) new combination (previously Chrysso nigra) and a yet...

  3. Response of Tuta absoluta (Lepidoptera: Gelechiidae) to different pheromone emission levels in greenhouse tomato crops.

    Science.gov (United States)

    Vacas, Sandra; López, Jesús; Primo, Jaime; Navarro-Llopis, Vicente

    2013-10-01

    The response of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) to different emission rates of its pheromone, (3E, 8Z, 11Z)-tetradecatrienyl acetate, was measured in two greenhouse trials with traps baited with mesoporous dispensers. For this purpose, weekly moth trap catches were correlated with increasing pheromone emission levels by multiple regression analysis. Pheromone release profiles of the dispensers were obtained by residual pheromone extraction and gas chromatography quantification. In the first trial carried out in summer 2010, effect of pheromone emission was significant as catches increased linearly with pheromone release rates up to the highest studied level of 46.8 μg/d. A new trial was carried out in spring 2011 to measure the effect of the emission factor when pheromone release rates were higher. Results demonstrated that trap catches and pheromone emission fitted to a quadratic model, with maximum catches obtained with a release level of 150.3 μg/d of (3E, 8Z, 11Z)-tetradecatrienyl acetate. This emission value should provide enhanced attraction of T. absoluta and improve mass trapping, attract-and-kill, or monitoring techniques under greenhouse conditions in the Mediterranean area.

  4. Hormonal Interference with Pheromone Systems in Parasitic Acarines, Especially Ixodid Ticks.

    Science.gov (United States)

    1982-05-01

    1) Precocity of molting as evidenced by stadium (larval, nymphal) deletion, (2) antigonadotrophic activity , (3) diapause induction, (4) ovicidal ...females. Studies to determine whether sex pheromone activity in D. variabilis can be affected by administration of ecdysteroids are being continued, but...Pheromone Activity in Hyalomm- dromedarii, With Evidence of the Existence of Ecdysteroids in H. dromedarii and Dermacentor variabilis

  5. Geometric isomers of sex pheromone components do not affect attractancy of Conopomorpha cramerella in cocoa plantations

    Science.gov (United States)

    Sex pheromone of cocoa pod borer (CPB), Conopomorpha cramerella, has previously been identified as a blend of (E,Z,Z)- and (E,E,Z)-4,6,10-hexadecatrienyl acetates and the corresponding alcohols. These pheromone components have been synthesized with modification of the existing method and relative at...

  6. Pheromone-mediated aggregation in nonsocial arthropods: an evolutionary ecological perspective

    NARCIS (Netherlands)

    Wertheim, B.; van Baalen, E-J.A.; Dicke, M.; Vet, L.E.M.

    2005-01-01

    Although the use of aggregation pheromones has been reported for hundreds of nonsocial arthropod species, the evolutionary ecological aspects of this behavior have received little attention. Despite the elaborate literature on mechanisms, robust data on costs and benefits of aggregation pheromones a

  7. Pheromone-mediated aggregation in nonsocial arthropods : An evolutionary ecological perspective

    NARCIS (Netherlands)

    Wertheim, B; van Baalen, EJA; Dicke, M; Vet, LEM

    2005-01-01

    Although the use of aggregation pheromones has been reported for hundreds of nonsocial arthropod species, the evolutionary ecological aspects of this behavior have received little attention. Despite the elaborate literature on mechanisms. robust data on costs and benefits of aggregation pheromones a

  8. Concise syntheses of insect pheromones using Z-selective cross metathesis.

    Science.gov (United States)

    Herbert, Myles B; Marx, Vanessa M; Pederson, Richard L; Grubbs, Robert H

    2013-01-02

    Very short synthetic routes to nine cis-olefin-containing pheromones containing a variety of functionality, including an unconjugated (E,Z) diene, are reported. These lepidopteran pheromones are used extensively for pest control, and were easily prepared using ruthenium-based Z-selective cross metathesis, highlighting the advantages of this method over less efficient ways to form Z olefins.

  9. Behavioural plasticity in support of a benefit for aggregation pheromone use in Drosophila melanogaster

    NARCIS (Netherlands)

    Wertheim, B; Dicke, Marcel; Vet, LEM

    2002-01-01

    We explored behavioural plasticity in the use of aggregation pheromone in the fruit fly Drosophila melanogaster Meigen (Diptera: Drosophilidae). Based on previous field observations, we formulated two hypotheses on a benefit of using aggregation pheromone for aggregated oviposition. One hypothesis c

  10. Nonadecadienone, a new termite trail-following pheromone identified in Glossotermes oculatus (Serritermitidae).

    Science.gov (United States)

    Hanus, Robert; Šobotník, Jan; Krasulová, Jana; Jiroš, Pavel; Žáček, Petr; Kalinová, Blanka; Dolejšová, Klára; Cvačka, Josef; Bourguignon, Thomas; Roisin, Yves; Lacey, Michael J; Sillam-Dussès, David

    2012-01-01

    Within the multitude of chemical signals used by termites, the trail marking by means of pheromones is ubiquitous. Chemistry and biology of the trail-following communication have been described in more than 60 species from all families except for the Neotropical Serritermitidae. The chemical ecology of Serritermitidae is of special interest not only as a missing piece of knowledge on the diversity and evolution of isopteran pheromones but also because it may contribute to the debate on the phylogenetic position of this family, which is still unresolved. Therefore, we aimed in this study to identify the trail-following pheromone of the serritermitid Glossotermes oculatus. Based on a combined approach of analytical chemistry, electrophysiology, and behavioral bioassays, we propose (10Z,13Z)-nonadeca-10,13-dien-2-one to be the trail-following pheromone of G. oculatus, secreted by the sternal gland of pseudergates. Thus, we report on a new termite trail-following pheromone of an unexpected chemical structure, a ketone with 19 carbons, contrasting with unsaturated alcohols containing 12 carbons as trail-following pheromones in other advanced termite families. In addition to this unique trail-following pheromone, we also describe the sternal gland in pseudergates as an organ of unusual shape, size, and structure when compared with other isopteran species. These results underline the peculiarity of the family Serritermitidae and prompt our interest in the chemistry of pheromones in the other genus of the family, Serritermes.

  11. Genetic dissection of pheromone processing reveals main olfactory system-mediated social behaviors in mice.

    Science.gov (United States)

    Matsuo, Tomohiko; Hattori, Tatsuya; Asaba, Akari; Inoue, Naokazu; Kanomata, Nobuhiro; Kikusui, Takefumi; Kobayakawa, Reiko; Kobayakawa, Ko

    2015-01-20

    Most mammals have two major olfactory subsystems: the main olfactory system (MOS) and vomeronasal system (VNS). It is now widely accepted that the range of pheromones that control social behaviors are processed by both the VNS and the MOS. However, the functional contributions of each subsystem in social behavior remain unclear. To genetically dissociate the MOS and VNS functions, we established two conditional knockout mouse lines that led to either loss-of-function in the entire MOS or in the dorsal MOS. Mice with whole-MOS loss-of-function displayed severe defects in active sniffing and poor survival through the neonatal period. In contrast, when loss-of-function was confined to the dorsal MOB, sniffing behavior, pheromone recognition, and VNS activity were maintained. However, defects in a wide spectrum of social behaviors were observed: attraction to female urine and the accompanying ultrasonic vocalizations, chemoinvestigatory preference, aggression, maternal behaviors, and risk-assessment behaviors in response to an alarm pheromone. Functional dissociation of pheromone detection and pheromonal induction of behaviors showed the anterior olfactory nucleus (AON)-regulated social behaviors downstream from the MOS. Lesion analysis and neural activation mapping showed pheromonal activation in multiple amygdaloid and hypothalamic nuclei, important regions for the expression of social behavior, was dependent on MOS and AON functions. Identification of the MOS-AON-mediated pheromone pathway may provide insights into pheromone signaling in animals that do not possess a functional VNS, including humans.

  12. Chemoreception to aggregation pheromones in the common bed bug, Cimex lectularius.

    Science.gov (United States)

    Liu, Feng; Xiong, Caixing; Liu, Nannan

    2017-03-01

    The common bed bug, Cimex lectularius, is an obligate blood-feeding insect that is resurgent worldwide, posing a threat to human beings through its biting nuisance and disease transmission. Bed bug aggregation pheromone is considered a very promising attractant for use in the monitoring and management of bed bugs, but as yet little is known regarding the sensory physiology of bed bugs related to this pheromone. This study examined how the individual components of aggregation pheromone are perceived by the olfactory receptor neurons (ORNs) housed in different types of olfactory sensilla in bed bugs and the molecular basis for the ORNs' responses to the aggregation pheromone. We found that the ORNs in the D olfactory sensilla played a predominant role in detecting all the components of aggregation pheromone except for histamine, which was only recognized by the C sensilla. Bed bugs' E sensilla, which include four functionally distinct groups, showed only a very weak but variant sensitivity (both excitatory and inhibitory) to the components of aggregation pheromone. Functional tests of 15 odorant receptors (ORs) in response to the components of aggregation pheromone revealed that most of these components were encoded by multiple ORs with various tuning properties. This study provides a comprehensive understanding of how bed bug aggregation pheromone is perceived and recognized in the peripheral olfactory system and will contribute useful information to support the development of synthetic attractants for bed bug monitoring and control.

  13. Oviposition behaviour as influenced by the oviposition deterring pheromone in the large white butterfly, Pieris brassicae

    NARCIS (Netherlands)

    Klijnstra, J.W.

    1985-01-01

    This thesis deals with a detailed analysis of egglaying behaviour of adult females of the Large White Butterfly, Pieris brassicae, and the way this behaviour is influenced by the oviposition deterring pheromone (ODP) in order to investigate the prospects for field application of this pheromone in ca

  14. Recent development in insect pheromone research, in particular in the Netherlands

    NARCIS (Netherlands)

    Ritter, F.J.; Persoons, C.J.

    1975-01-01

    A review is given of recent pheromone work carried out in the Netherlands on Lepidoptera, cockroaches, pharaoh's ants and termites, special emphasis being given to isolation and identification aspects. The sex pheromones of three leaf roller moths (Tortricidae) have been isolated, identified and fie

  15. Hormonal Interference with Pheromone Systems in Parasitic Acarines, Especially Ixodid Ticks.

    Science.gov (United States)

    1983-05-01

    Genital Pheromone(s); Precocene-2; Hyalomma dromedarii; Dermacentor variabilis; Radioimmunoassay; juvenile hormone; Dermanyssus gallinae 19. KEY...dromedarii; Dermacentor variabilis; Radioimmunoassay; juvenile hormone; Dermanyssus gallinae . 20. A STRACT (Continue on reverse side I nfecessry and...allatotropin Precocene-2 and the juvenile hormone, JH3, on reporduction in the chicken mite, Dermanyssus gallinae is described. These studies are part of

  16. Trapping effect of synthetic pheromone blends on two stem borers, Chilo suppressalis and Scripophaga incertulas

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Two internal feeders of rice plant, rice stem borer, Chilo suppressalis (Walker) and yellow stem borer, Scirpophaga incertulas (Walker) are major hurdles in achieving higher yields in Central China. Synthetic sex pheromone was an effective method to control the two borers. A new series of sex pheromone blends were formulated and tested.

  17. Pheromone biosynthesis activating neuropeptide receptors (PBANRs) in moths: New developments regarding alternative splice variants and the potential for targeted disruption of PBANR in pest control

    Science.gov (United States)

    For most moths, the ability of conspecific males to locate receptive females is governed by the detection of a blend of semiochemicals known as sex pheromones. Sex pheromone components are de novo synthesized in the female pheromone gland in response to pheromone biosynthesis activating neuropeptid...

  18. Assessing Greater Sage-Grouse Selection of Brood-Rearing Habitat Using Remotely-Sensed Imagery: Can Readily Available High-Resolution Imagery Be Used to Identify Brood-Rearing Habitat Across a Broad Landscape?

    Science.gov (United States)

    Westover, Matthew; Baxter, Jared; Baxter, Rick; Day, Casey; Jensen, Ryan; Petersen, Steve; Larsen, Randy

    2016-01-01

    Greater sage-grouse populations have decreased steadily since European settlement in western North America. Reduced availability of brood-rearing habitat has been identified as a limiting factor for many populations. We used radio-telemetry to acquire locations of sage-grouse broods from 1998 to 2012 in Strawberry Valley, Utah. Using these locations and remotely-sensed NAIP (National Agricultural Imagery Program) imagery, we 1) determined which characteristics of brood-rearing habitat could be used in widely available, high resolution imagery 2) assessed the spatial extent at which sage-grouse selected brood-rearing habitat, and 3) created a predictive habitat model to identify areas of preferred brood-rearing habitat. We used AIC model selection to evaluate support for a list of variables derived from remotely-sensed imagery. We examined the relationship of these explanatory variables at three spatial extents (45, 200, and 795 meter radii). Our top model included 10 variables (percent shrub, percent grass, percent tree, percent paved road, percent riparian, meters of sage/tree edge, meters of riparian/tree edge, distance to tree, distance to transmission lines, and distance to permanent structures). Variables from each spatial extent were represented in our top model with the majority being associated with the larger (795 meter) spatial extent. When applied to our study area, our top model predicted 75% of naïve brood locations suggesting reasonable success using this method and widely available NAIP imagery. We encourage application of our methodology to other sage-grouse populations and species of conservation concern.

  19. Assessing Greater Sage-Grouse Selection of Brood-Rearing Habitat Using Remotely-Sensed Imagery: Can Readily Available High-Resolution Imagery Be Used to Identify Brood-Rearing Habitat Across a Broad Landscape?

    Directory of Open Access Journals (Sweden)

    Matthew Westover

    Full Text Available Greater sage-grouse populations have decreased steadily since European settlement in western North America. Reduced availability of brood-rearing habitat has been identified as a limiting factor for many populations. We used radio-telemetry to acquire locations of sage-grouse broods from 1998 to 2012 in Strawberry Valley, Utah. Using these locations and remotely-sensed NAIP (National Agricultural Imagery Program imagery, we 1 determined which characteristics of brood-rearing habitat could be used in widely available, high resolution imagery 2 assessed the spatial extent at which sage-grouse selected brood-rearing habitat, and 3 created a predictive habitat model to identify areas of preferred brood-rearing habitat. We used AIC model selection to evaluate support for a list of variables derived from remotely-sensed imagery. We examined the relationship of these explanatory variables at three spatial extents (45, 200, and 795 meter radii. Our top model included 10 variables (percent shrub, percent grass, percent tree, percent paved road, percent riparian, meters of sage/tree edge, meters of riparian/tree edge, distance to tree, distance to transmission lines, and distance to permanent structures. Variables from each spatial extent were represented in our top model with the majority being associated with the larger (795 meter spatial extent. When applied to our study area, our top model predicted 75% of naïve brood locations suggesting reasonable success using this method and widely available NAIP imagery. We encourage application of our methodology to other sage-grouse populations and species of conservation concern.

  20. The origin and evolution of social insect queen pheromones: Novel hypotheses and outstanding problems.

    Science.gov (United States)

    Oi, Cintia A; van Zweden, Jelle S; Oliveira, Ricardo C; Van Oystaeyen, Annette; Nascimento, Fabio S; Wenseleers, Tom

    2015-07-01

    Queen pheromones, which signal the presence of a fertile queen and induce daughter workers to remain sterile, are considered to play a key role in regulating the reproductive division of labor of insect societies. Although queen pheromones were long thought to be highly taxon-specific, recent studies have shown that structurally related long-chain hydrocarbons act as conserved queen signals across several independently evolved lineages of social insects. These results imply that social insect queen pheromones are very ancient and likely derived from an ancestral signalling system that was already present in their common solitary ancestors. Based on these new insights, we here review the literature and speculate on what signal precursors social insect queen pheromones may have evolved from. Furthermore, we provide compelling evidence that these pheromones should best be seen as honest signals of fertility as opposed to suppressive agents that chemically sterilize the workers against their own best interests.

  1. The alarm pheromone in male rats as a unique anxiety model: psychopharmacological evidence using anxiolytics.

    Science.gov (United States)

    Inagaki, Hideaki; Kiyokawa, Yasushi; Takeuchi, Yukari; Mori, Yuji

    2010-02-01

    Previously, we demonstrated that an alarm pheromone released from male donor Wistar rats evoked anxiety-related physiological and behavioral responses in recipient rats. Thus, we believe that this pheromone may increase anxiety levels in rats. In the current study, we evaluated the predictive validity of this alarm pheromone-induced anxiogenic effect in detail by investigating whether six types of human anxiolytics, each of which has a different mechanism of action, were efficacious in reducing anxiety, using changes in the acoustic startle reflex (ASR) as an index. The alarm pheromone-enhanced ASR was not affected by vehicle pretreatment but was dose-dependently attenuated by pretreatment with midazolam, phenelzine, propranolol, clonidine, and CP-154,526-although not buspirone. These results may reflect some aspects of the predictive validity of the alarm pheromone-induced anxiety in rats as an animal model of human anxiety.

  2. Two Neuronal G Proteins Are Involved in Chemosensation of the Caenorhabditis Elegans Dauer-Inducing Pheromone

    Science.gov (United States)

    Zwaal, R. R.; Mendel, J. E.; Sternberg, P. W.; Plasterk, RHA.

    1997-01-01

    Caenorhabditis elegans uses chemosensation to determine its course of development. Young larvae can arrest as dauer larvae in response to increasing population density, which they measure by a nematode-excreted pheromone, and decreasing food supply. Dauer larvae can resume development in response to a decrease in pheromone and increase in food concentration. We show here that two novel G protein alpha subunits (GPA-2 and GPA-3) show promoter activity in subsets of chemosensory neurons and are involved in the decision to form dauer larvae primarily through the response to dauer pheromone. Dominant activating mutations in these G proteins result in constitutive, pheromone-independent dauer formation, whereas inactivation results in reduced sensitivity to pheromone, and, under certain conditions, an alteration in the response to food. Interactions between gpa-2, gpa-3 and other genes controlling dauer formation suggest that these G proteins may act in parallel to regulate the neuronal decision making that precedes dauer formation. PMID:9055081

  3. Responses to Pheromones in a Complex Odor World: Sensory Processing and Behavior

    Science.gov (United States)

    Deisig, Nina; Dupuy, Fabienne; Anton, Sylvia; Renou, Michel

    2014-01-01

    Insects communicating with pheromones, be it sex- or aggregation pheromones, are confronted with an olfactory environment rich in a diversity of volatile organic compounds of which plants are the main releaser. Certain of these volatiles can represent behaviorally relevant information, such as indications about host- or non-host plants; others will provide essentially a rich odor background out of which the behaviorally relevant information needs to be extracted. In an attempt to disentangle mechanisms of pheromone communication in a rich olfactory environment, which might underlie interactions between intraspecific signals and a background, we will summarize recent literature on pheromone/plant volatile interactions. Starting from molecular mechanisms, describing the peripheral detection and central nervous integration of pheromone-plant volatile mixtures, we will end with behavioral output in response to such mixtures and its plasticity. PMID:26462691

  4. Responses to Pheromones in a Complex Odor World: Sensory Processing and Behavior

    Directory of Open Access Journals (Sweden)

    Nina Deisig

    2014-06-01

    Full Text Available Insects communicating with pheromones, be it sex- or aggregation pheromones, are confronted with an olfactory environment rich in a diversity of volatile organic compounds of which plants are the main releaser. Certain of these volatiles can represent behaviorally relevant information, such as indications about host- or non-host plants; others will provide essentially a rich odor background out of which the behaviorally relevant information needs to be extracted. In an attempt to disentangle mechanisms of pheromone communication in a rich olfactory environment, which might underlie interactions between intraspecific signals and a background, we will summarize recent literature on pheromone/plant volatile interactions. Starting from molecular mechanisms, describing the peripheral detection and central nervous integration of pheromone-plant volatile mixtures, we will end with behavioral output in response to such mixtures and its plasticity.

  5. Asexual reproduction does not produce clonal populations of the brooding coral Pocillopora damicornis on the Great Barrier Reef, Australia

    Science.gov (United States)

    Sherman, C. D. H.; Ayre, D. J.; Miller, K. J.

    2006-03-01

    We have investigated the relationship between genotypic diversity, the mode of production of brooded larvae and disturbance in a range of reef habitats, in order to resolve the disparity between the reproductive mode and population structure reported for the brooding coral Pocillopora damicornis. Within 14 sites across six habitats, the ratio of the observed ( G o) to the expected ( G e) genotypic diversity ranged from 69 to 100% of that expected for random mating. At three other sites in two habitats the G o /G e ranged from 35 to 53%. Two of these sites were recently bleached, suggesting that asexual recruitment may be favoured after disturbance. Nevertheless, our data suggest that brooded larvae, from each of five habitats surveyed, were asexually produced. While clonal recruitment may be important in disturbed habitats, the lack of clonality detected, both in this and earlier surveys of 40 other sites, implies that a disturbance is normally insufficient to explain this species’ continued investment in clonal reproduction.

  6. Ostrinia revisited: Evidence for sex linkage in European Corn Borer Ostrinia nubilalis (Hubner pheromone reception

    Directory of Open Access Journals (Sweden)

    Heckel David G

    2010-09-01

    Full Text Available Abstract Background The European Corn Borer, Ostrinia nubilalis (Hubner, is a keystone model for studies on the evolution of sex pheromone diversity and its role in establishing reproductive isolation. This species consists of two sympatric races, each utilizing opposite isomers of the same compound as their major pheromone component. Female production and male response are congruent in each race, and males from each strain exhibit phenotypic differences in peripheral physiology. Both strains possess co-localized pheromone-sensitive olfactory sensory neurons characterized by a larger amplitude action potential (spike responding to the major pheromone component, and a smaller spike amplitude cell responding to the minor component, i.e. the opposite isomer. These differences in amplitude correspond to differences in dendritic diameter between the two neurons. Previous studies showed that behavioral response to the pheromone blend was sex-linked, but spike amplitude response to pheromone components matched autosomal, not sex-linked inheritance. Results As part of a larger study to finely map the loci responsible for pheromone communication in this species, we have reanalyzed peripheral physiology among parental, and first and second generation hybrids between the two pheromone strains using tungsten electrode electrophysiology. Our results reveal that differences in spike amplitude ratio between male pheromone-sensitive sensory neurons in O. nubilalis races are controlled, at least partially, by sex-linked genes that exhibit E-strain dominance. Conclusions We propose that peripheral olfactory response in O. nubilalis may be affected both by autosomal and sex-linked genes exhibiting a cross-locus dominance effect, and suggest that the genetic basis for pheromone reception and response in the species is more closely linked than previously thought.

  7. Ant foraging on complex trails: route learning and the role of trail pheromones in Lasius niger.

    Science.gov (United States)

    Czaczkes, Tomer J; Grüter, Christoph; Ellis, Laura; Wood, Elizabeth; Ratnieks, Francis L W

    2013-01-15

    Ants are central place foragers and use multiple information sources to navigate between the nest and feeding sites. Individual ants rapidly learn a route, and often prioritize memory over pheromone trails when tested on a simple trail with a single bifurcation. However, in nature, ants often forage at locations that are reached via more complex routes with multiple trail bifurcations. Such routes may be more difficult to learn, and thus ants would benefit from additional information. We hypothesized that trail pheromones play a more significant role in ant foraging on complex routes, either by assisting in navigation or route learning or both. We studied Lasius niger workers foraging on a doubly bifurcating trail with four end points. Route learning was slower and errors greater on alternating (e.g. left-right) versus repeating routes (e.g. left-left), with error rates of 32 and 3%, respectively. However, errors on alternating routes decreased by 30% when trail pheromone was present. Trail pheromones also aid route learning, leading to reduced errors in subsequent journeys without pheromone. If an experienced forager makes an error when returning to a food source, it reacts by increasing pheromone deposition on the return journey. In addition, high levels of trail pheromone suppress further pheromone deposition. This negative feedback mechanism may act to conserve pheromone or to regulate recruitment. Taken together, these results demonstrate further complexity and sophistication in the foraging system of ant colonies, especially in the role of trail pheromones and their relationship with learning and the use of private information (memory) in a complex environment.

  8. High individual variation in pheromone production by tree-killing bark beetles (Coleoptera: Curculionidae: Scolytinae)

    Science.gov (United States)

    Pureswaran, Deepa S.; Sullivan, Brian T.; Ayres, Matthew P.

    2008-01-01

    Aggregation via pheromone signalling is essential for tree-killing bark beetles to overcome tree defenses and reproduce within hosts. Pheromone production is a trait that is linked to fitness, so high individual variation is paradoxical. One explanation is that the technique of measuring static pheromone pools overestimates true variation among individuals. An alternative hypothesis is that aggregation behaviour dilutes the contribution of individuals to the trait under selection and reduces the efficacy of natural selection on pheromone production by individuals. We compared pheromone measurements from traditional hindgut extractions of female southern pine beetles with those obtained by aerating individuals till they died. Aerations showed greater total pheromone production than hindgut extractions, but coefficients of variation (CV) remained high (60-182%) regardless of collection technique. This leaves the puzzle of high variation unresolved. A novel but simple explanation emerges from considering bark beetle aggregation behaviour. The phenotype visible to natural selection is the collective pheromone plume from hundreds of colonisers. The influence of a single beetle on this plume is enhanced by high variation among individuals but constrained by large group sizes. We estimated the average contribution of an individual to the pheromone plume across a range of aggregation sizes and showed that large aggregation sizes typical in mass attacks limit the potential of natural selection because each individual has so little effect on the overall plume. Genetic variation in pheromone production could accumulate via mutation and recombination, despite strong effects of the pheromone plume on the fitness of individuals within the aggregation. Thus, aggregation behaviour, by limiting the efficacy of natural selection, can allow the persistence of extreme phenotypes in nature.

  9. Age-dependent plasticity of sex pheromone response in the moth, Agrotis ipsilon: combined effects of octopamine and juvenile hormone

    DEFF Research Database (Denmark)

    Jarriault, David; Barrozo, Romina B; de Carvalho Pinto, Carlos J

    2009-01-01

    Male moths use sex pheromones to find their mating partners. In the moth, Agrotis ipsilon, the behavioral response and the neuron sensitivity within the primary olfactory centre, the antennal lobe (AL), to sex pheromone increase with age and juvenile hormone (JH) biosynthesis. By manipulating...... the effects of OA and an OA receptor antagonist, mianserin, on behavioral and AL neuron responses of mature and immature males during stimulation with sex pheromone. Our results indicate that, although OA injections enhanced the behavioral pheromone response in mature males, OA had no significant effect...... a behavioral response of A. ipsilon males to sex pheromone....

  10. Effect of pheromone induction on transfer of the Enterococcus faecalis plasmid pCF10 in intestinal mucus ex vivo

    DEFF Research Database (Denmark)

    Licht, Tine Rask; Hammerum, Anette Marie; Jensen, Lars Bogø;

    2001-01-01

    The effect of synthetic sex pheromone on pheromone-inducible conjugation between the isogenic Enterococcus faecalis strains OG1RF and OG1SS was investigated in (i) Todd-Hewitt broth medium and (ii) intestinal mucus isolated from germ-free rats. In broth, the presence of synthetic pheromone cCF10...... in the experiment. We suggest that due to differences in diffusion rates and medium-binding of the pheromones, the effect of the synthetic cCF10 was immediately dominated by the effect of pheromones produced by the recipient E. faecalis strain in broth, while this happened later in mucus....

  11. Geographical matching of volatile signals and pollinator olfactory responses in a cycad brood-site mutualism.

    Science.gov (United States)

    Suinyuy, Terence N; Donaldson, John S; Johnson, Steven D

    2015-10-07

    Brood-site mutualisms represent extreme levels of reciprocal specialization between plants and insect pollinators, raising questions about whether these mutualisms are mediated by volatile signals and whether these signals and insect responses to them covary geographically in a manner expected from coevolution. Cycads are an ancient plant lineage in which almost all extant species are pollinated through brood-site mutualisms with insects. We investigated whether volatile emissions and insect olfactory responses are matched across the distribution range of the African cycad Encephalartos villosus. This cycad species is pollinated by the same beetle species across its distribution, but cone volatile emissions are dominated by alkenes in northern populations, and by monoterpenes and a pyrazine compound in southern populations. In reciprocal choice experiments, insects chose the scent of cones from the local region over that of cones from the other region. Antennae of beetles from northern populations responded mainly to alkenes, while those of beetles from southern populations responded mainly to pyrazine. In bioassay experiments, beetles were most strongly attracted to alkenes in northern populations and to the pyrazine compound in southern populations. Geographical matching of cone volatiles and pollinator olfactory preference is consistent with coevolution in this specialized mutualism.

  12. Strategic variation in mobbing as a front line of defense against brood parasitism.

    Science.gov (United States)

    Welbergen, Justin A; Davies, Nicholas B

    2009-02-10

    Coevolutionary arms races, where adaptations in one party select for counter-adaptations in another and vice versa, are fundamental to interactions between organisms and their predators, pathogens, and parasites [1]. Avian brood parasites and their hosts have emerged as model systems for studying such reciprocal coevolutionary processes [2, 3]. For example, hosts have evolved changes in egg appearance and rejection of foreign eggs in response to brood parasitism from cuckoos, and cuckoos have evolved host-egg mimicry as a counter-response [4-6]. However, the host's front line of defense is protecting the nest from being parasitized in the first place [7-10], yet little is known about the effectiveness of nest defense as an antiparasite adaptation, and its coevolutionary significance remains poorly understood [10]. Here we show first that mobbing of common cuckoos Cuculus canorus by reed warblers Acrocephalus scirpaceus is an effective defense against parasitism. Second, mobbing of cuckoos is a phenotypically plastic trait that is modified strategically according to local parasitism risk. This supports the view that hosts use a "defense in-depth strategy," with successive flexible lines of defense that coevolve with corresponding offensive lines of the parasite. This highlights the need for more holistic research into the coevolutionary consequences when multiple adaptations and counter-adaptations evolve in concert [11].

  13. Coevolution in action: disruptive selection on egg colour in an avian brood parasite and its host.

    Directory of Open Access Journals (Sweden)

    Canchao Yang

    Full Text Available BACKGROUND: Trait polymorphism can evolve as a consequence of frequency-dependent selection. Coevolutionary interactions between hosts and parasites may lead to selection on both to evolve extreme phenotypes deviating from the norm, through disruptive selection. METHODOLOGY/PRINCIPAL FINDING: Here, we show through detailed field studies and experimental procedures that the ashy-throated parrotbill (Paradoxornis alphonsianus and its avian brood parasite, the common cuckoo (Cuculus canorus, have both evolved egg polymorphism manifested in discrete immaculate white, pale blue, and blue egg phenotypes within a single population. In this host-parasite system the most common egg colours were white and blue, with no significant difference in parasitism rates between hosts laying eggs of either colour. Furthermore, selection on parasites for countering the evolution of host egg types appears to be strong, since ashy-throated parrotbills have evolved rejection abilities for even partially mimetic eggs. CONCLUSIONS/SIGNIFICANCE: The parrotbill-cuckoo system constitutes a clear outcome of disruptive selection on both host and parasite egg phenotypes driven by coevolution, due to the cost of parasitism in the host and by host defences in the parasite. The present study is to our knowledge the first to report the influence of disruptive selection on evolution of discrete phenotypes in both parasite and host traits in an avian brood parasitism system.

  14. Coevolutionary interactions between farmers and mafia induce host acceptance of avian brood parasites.

    Science.gov (United States)

    Abou Chakra, Maria; Hilbe, Christian; Traulsen, Arne

    2016-05-01

    Brood parasites exploit their host in order to increase their own fitness. Typically, this results in an arms race between parasite trickery and host defence. Thus, it is puzzling to observe hosts that accept parasitism without any resistance. The 'mafia' hypothesis suggests that these hosts accept parasitism to avoid retaliation. Retaliation has been shown to evolve when the hosts condition their response to mafia parasites, who use depredation as a targeted response to rejection. However, it is unclear if acceptance would also emerge when 'farming' parasites are present in the population. Farming parasites use depredation to synchronize the timing with the host, destroying mature clutches to force the host to re-nest. Herein, we develop an evolutionary model to analyse the interaction between depredatory parasites and their hosts. We show that coevolutionary cycles between farmers and mafia can still induce host acceptance of brood parasites. However, this equilibrium is unstable and in the long-run the dynamics of this host-parasite interaction exhibits strong oscillations: when farmers are the majority, accepters conditional to mafia (the host will reject first and only accept after retaliation by the parasite) have a higher fitness than unconditional accepters (the host always accepts parasitism). This leads to an increase in mafia parasites' fitness and in turn induce an optimal environment for accepter hosts.

  15. Brain size and morphology of the brood-parasitic and cerophagous honeyguides (Aves: Piciformes).

    Science.gov (United States)

    Corfield, Jeremy R; Birkhead, Tim R; Spottiswoode, Claire N; Iwaniuk, Andrew N; Boogert, Neeltje J; Gutiérrez-Ibáñez, Cristian; Overington, Sarah E; Wylie, Douglas R; Lefebvre, Louis

    2013-01-01

    Honeyguides (Indicatoridae, Piciformes) are unique among birds in several respects. All subsist primarily on wax, are obligatory brood parasites and one species engages in 'guiding' behavior in which it leads human honey hunters to bees' nests. This unique life history has likely shaped the evolution of their brain size and morphology. Here, we test that hypothesis using comparative data on relative brain and brain region size of honeyguides and their relatives: woodpeckers, barbets and toucans. Honeyguides have significantly smaller relative brain volumes than all other piciform taxa. Volumetric measurements of the brain indicate that honeyguides have a significantly larger cerebellum and hippocampal formation (HF) than woodpeckers, the sister clade of the honeyguides, although the HF enlargement was not significant across all of our analyses. Cluster analyses also revealed that the overall composition of the brain and telencephalon differs greatly between honeyguides and woodpeckers. The relatively smaller brains of the honeyguides may be a consequence of brood parasitism and cerophagy ('wax eating'), both of which place energetic constraints on brain development and maintenance. The inconclusive results of our analyses of relative HF volume highlight some of the problems associated with comparative studies of the HF that require further study.

  16. Elevated temperature alters the lunar timing of Planulation in the brooding coral Pocillopora damicornis.

    Directory of Open Access Journals (Sweden)

    Camerron M Crowder

    Full Text Available Reproductive timing in corals is associated with environmental variables including temperature, lunar periodicity, and seasonality. Although it is clear that these variables are interrelated, it remains unknown if one variable in particular acts as the proximate signaler for gamete and or larval release. Furthermore, in an era of global warming, the degree to which increases in ocean temperatures will disrupt normal reproductive patterns in corals remains unknown. Pocillopora damicornis, a brooding coral widely distributed in the Indo-Pacific, has been the subject of multiple reproductive ecology studies that show correlations between temperature, lunar periodicity, and reproductive timing. However, to date, no study has empirically measured changes in reproductive timing associated with increased seawater temperature. In this study, the effect of increased seawater temperature on the timing of planula release was examined during the lunar cycles of March and June 2012. Twelve brooding corals were removed from Hobihu reef in Nanwan Bay, southern Taiwan and placed in 23 and 28°C controlled temperature treatment tanks. For both seasons, the timing of planulation was found to be plastic, with the high temperature treatment resulting in significantly earlier peaks of planula release compared to the low temperature treatment. This suggests that temperature alone can influence the timing of larval release in Pocillopora damicornis in Nanwan Bay. Therefore, it is expected that continued increases in ocean temperature will result in earlier timing of reproductive events in corals, which may lead to either variations in reproductive success or phenotypic acclimatization.

  17. Snake River Fall Chinook Salmon Brood-Stock Program, 1984 Annual Report of Research.

    Energy Technology Data Exchange (ETDEWEB)

    Harrell, Lee W.

    1985-02-01

    The objective is the enhancement of upriver stocks through research and development of an eggbank source. Viable gametes, produced from fish held to maturity in sea pens, will be made available for restoration purposes on the Snake River. Seawater entry trials with 0+-age and 1+-age fish have shown that 0+-age Snake River fall chinook salmon are not amenable to seawater entry and will either die or require up to 6 months to fully adapt to seawater. However, 1+-age smolts experience little problem at seawater entry; it is therefore suggested that Snake River fall chinook salmon be released as 1+ smolting fish in hatchery situations. Important marine mortalities occurring from osmoregulatory dysfunction, Bacterial Kidney Disease, and precocity at various life stages have been documented. Also, a previously unreported marine fungal pathogen has been identified. Mortality from this pathogen occurs from 3-years of age to maturity and can exceed 0.5% per day (resulting in losses to 90+%). At the end of December 1984, Snake River fall chinook salmon from 1980 (n = 67), 1981 (n = 876), 1982 (n = 4809), and 1983 (n = 7100) broods were under production. Because of the extensive mortality due to the marine fungal pathogen, only seven spawners were obtained from the 1980 stock in fall 1984. The 1980-brood spawners produced only minimal eggs and these will be used to investigate possible vertical transmission of the fungal pathogen. 4 figs.

  18. Pheromones and signature mixtures: defining species-wide signals and variable cues for identity in both invertebrates and vertebrates.

    Science.gov (United States)

    Wyatt, Tristram D

    2010-10-01

    Pheromones have been found in species in almost every part of the animal kingdom, including mammals. Pheromones (a molecule or defined combination of molecules) are species-wide signals which elicit innate responses (though responses can be conditional on development as well as context, experience, and internal state). In contrast, signature mixtures, in invertebrates and vertebrates, are variable subsets of molecules of an animal's chemical profile which are learnt by other animals, allowing them to distinguish individuals or colonies. All signature mixtures, and almost all pheromones, whatever the size of molecules, are detected by olfaction (as defined by receptor families and glomerular processing), in mammals by the main olfactory system or vomeronasal system or both. There is convergence on a glomerular organization of olfaction. The processing of all signature mixtures, and most pheromones, is combinatorial across a number of glomeruli, even for some sex pheromones which appear to have 'labeled lines'. Narrowly specific pheromone receptors are found, but are not a prerequisite for a molecule to be a pheromone. A small minority of pheromones act directly on target tissues (allohormone pheromones) or are detected by non-glomerular chemoreceptors, such as taste. The proposed definitions for pheromone and signature mixture are based on the heuristic value of separating these kinds of chemical information. In contrast to a species-wide pheromone, there is no single signature mixture to find, as signature mixtures are a 'receiver-side' phenomenon and it is the differences in signature mixtures which allow animals to distinguish each other.

  19. An agent-based model to investigate the roles of attractive and repellent pheromones in ant decision making during foraging.

    Science.gov (United States)

    Robinson, Elva J H; Ratnieks, Francis L W; Holcombe, M

    2008-11-21

    Pharaoh's ants organise their foraging system using three types of trail pheromone. All previous foraging models based on specific ant foraging systems have assumed that only a single attractive pheromone is used. Here we present an agent-based model based on trail choice at a trail bifurcation within the foraging trail network of a Pharaoh's ant colony which includes both attractive (positive) and repellent (negative) trail pheromones. Experiments have previously shown that Pharaoh's ants use both types of pheromone. We investigate how the repellent pheromone affects trail choice and foraging success in our simulated foraging system. We find that both the repellent and attractive pheromones have a role in trail choice, and that the repellent pheromone prevents random fluctuations which could otherwise lead to a positive feedback loop causing the colony to concentrate its foraging on the unrewarding trail. An emergent feature of the model is a high level of variability in the level of repellent pheromone on the unrewarding branch. This is caused by the repellent pheromone exerting negative feedback on its own deposition. We also investigate the dynamic situation where the location of the food is changed after foraging trails are established. We find that the repellent pheromone has a key role in enabling the colony to refocus the foraging effort to the new location. Our results show that having a repellent pheromone is adaptive, as it increases the robustness and flexibility of the colony's overall foraging response.

  20. Pheromone attraction and cross-attraction of Nezara, Acrosternum, and Euschistus spp. stink bugs (Heteroptera: Pentatomidae) in the field.

    Science.gov (United States)

    Tillman, P G; Aldrich, J R; Khrimian, A; Cottrell, T E

    2010-04-01

    Detecting infestations of stink bugs (Heteroptera: Pentatomidae) using pheromones remains problematic, particularly so in the United States for the exotic stink bug, Nezara viridula L., and our native stink bug, Acrosternum hilare (Say). Therefore, we conducted a 2-yr on-farm study to examine the attractiveness and possible cross-attraction of the reported pheromones for N. viridula and A. hilare and those previously discovered for Euschistus servus (Say) and Plautia stali Scott to N. viridula, A. hilare, and E. servus. The attractiveness of selected pentatomid pheromones to tachinid parasitoids of stink bugs was also examined. We showed for the first time under field conditions that N. viridula can be trapped with its reported pheromone, a 3:1 trans- to cis-(Z)-alpha-bisabolene epoxide blend. In fact, attraction of N. viridula increased with higher pheromone doses. Traps baited with a 5:95 trans- to cis-(Z)-alpha-bisabolene epoxide blend, the reported male-produced A. hilare attractant pheromone, failed to attract significantly more A. hilare than did unbaited control traps. Instead A. hilare was significantly cross-attracted to the P. stali pheromone [methyl (E,E,Z)-2,4,6-decatrienoate]. The E. servus pheromone [methyl (E,Z)-2,4-decadienoate], either alone or in combination with P. stali pheromone, was more attractive to E. servus than to N. viridula, P. stali, or A. hilare pheromones. In general, tachinid parasitoids were found responsive to the male-specific volatiles of their known hosts, including the attractiveness of Trichopoda pennipes (F.) to sesquiterpenoid blends characteristic of A. hilare and N. viridula. A tachinid parasitoid of E. servus, Cylindromyia sp., seemed to be attracted to E. servus pheromone. In conclusion, our results indicate that stink bug traps baited with lures containing N. viridula pheromone blend, P. stali pheromone, and E. servus pheromone have the greatest potential for detecting populations of N. viridula, A. hilare, and E

  1. Methyl trisporate E. A sex pheromone in Phycomyces blakesleeanus.

    Science.gov (United States)

    Miller, M L; Sutter, R P

    1984-05-25

    Combined mating type cultures of Phycomyces blakesleeanus accumulate 41 mg of trisporic acids/l of medium, of which 30% is trisporic acid E. The methyl ester of trisporic acid E exhibits the same zygophore -inducing activity in bioassays with P. blakesleeanus and Mucor mucedo as does the pheromone methyl trisporate C. The structure of methyl trisporate E is 1,5-dimethyl-2-hydroxyl-4-oxo-6-(2'-hydroxyl-6'- methylocta -5',7'-d ien-8'-yl) -5-cyclohexene-1-carboxylic acid methyl ester.

  2. Prediction of release ratios of multicomponent pheromones from rubber septa.

    Science.gov (United States)

    Heath, R R; Teal, P E; Tumlinson, J H; Mengelkoch, L J

    1986-12-01

    A method has been developed to predict the release ratio of the components of blends of alcohols, acetates, and/or aldehydes from rubber septa. The calculations of predicted release ratios are based on the relative vapor pressures of the components. The relative vapor pressures of the compounds were calculated from their retention indices on a liquid crystal capillary gas chromatographie column. The correlation between the theoretically predicted and experimentally determined ratios was very good. Thus, formulations can be prepared that will release a desired ratio of the components of a multicomponent pheromone blend.

  3. Observations on the removal of brood inoculated with Tropilaelaps mercedesae (Acari: Laelapidae) and the mite's reproductive success in Apis mellifera colonies.

    Science.gov (United States)

    Khongphinitbunjong, Kitiphong; de Guzman, Lilia I; Buawangpong, Ninat; Rinderer, Thomas E; Frake, Amanda M; Chantawannakul, Panuwan

    2014-01-01

    This study assessed the response of Apis mellifera to brood deliberately infested with Tropilaelaps mercedesae. The reproductive success of T. mercedesae in mite-inoculated and naturally infested brood was also compared. The presence of T. mercedesae inside brood cells significantly affected brood removal. Thai A. mellifera removed 52.6 ± 8.2 % of the brood inoculated with T. mercedesae as compared to 17.2 ± 1.8 and 5.7 ± 1.1 % removal rates for the groups of brood with their cell cappings opened and closed without mite inoculation and the control brood (undisturbed, no mite inoculation), respectively. Brood removal peaked during the second and third days post inoculation when test brood was at the prepupal stage. Overall, non-reproduction (NR) of foundress T. mercedesae was high. However, when NR was measured based on the criteria used for Varroa, the naturally infested pupae (NIP) supported the highest NR (92.8 %). Newly sealed larvae inoculated with Tropilaelaps collected from newly sealed larvae (NSL) had 78.2 % NR and those inoculated with Tropilaelaps collected from tan-bodied pupae (TBP) had 76.8 % NR. Since Tropilaelaps is known to have a short development period and nearly all progeny reach adulthood by the time of host emergence, we also used two Tropilaelaps-specific criteria to determine NR. Foundresses that did not produce progeny and those that produced only one progeny were considered NR. Using these two criteria, NR decreased tremendously but showed similar trends with means of 65, 40 and 33 % for NIP, NSL and TBP, respectively. High NR in the NIP group may indicate increased hygienic behavior in Thai A. mellifera colonies. The removal of infested prepupae or tan-bodied pupae will likely decrease the reproductive potential of Tropilaelaps. Our study suggests that brood removal may be one of the resistance mechanisms towards T. mercedesae by naturally adapted Thai A. mellifera.

  4. Factors Affecting Pheromone Production by the Pepper Weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae) and Collection Efficiency.

    Science.gov (United States)

    Eller, Fred J; Palmquist, Debra E

    2014-11-18

    Several factors affecting pheromone production by male pepper weevils, Anthonomus eugenii Cano (Coleoptera: Curculionidae) as well as collection efficiency were investigated. Factors studied included: porous polymer adsorbents (Tenax versus Super Q), male age, time of day, male density, and male diet. Super Q was found to be a superior adsorbent for the male-produced alcohols and geranic acid as well as the plant-produced E-β-ocimene. Pheromone production increased with male age up to about age 15 days old and then tapered off. Male pepper weevils produced the highest amount of pheromone between noon and 2 pm (i.e., 4 to 6 h after "lights on") and were producing ca. 800 ng/h during this period. Thereafter, pheromone production decreased and was extremely low during the scotophase (i.e., ca. 12 ng/h). Male pepper weevil density had a significant effect on both release rate and pheromone composition. Pheromone production on a per male basis was highest for individual males and the percentage of geranic acid in the blend was lowest for individual males. Male pepper weevils produced only extremely low amounts of pheromone when feeding on artificial diet; however, they produced very high amounts when on fresh peppers. Together, this information will be useful in designing better attractant lures for pepper weevils.

  5. Factors Affecting Pheromone Production by the Pepper Weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae and Collection Efficiency

    Directory of Open Access Journals (Sweden)

    Fred J. Eller

    2014-11-01

    Full Text Available Several factors affecting pheromone production by male pepper weevils, Anthonomus eugenii Cano (Coleoptera: Curculionidae as well as collection efficiency were investigated. Factors studied included: porous polymer adsorbents (Tenax versus Super Q, male age, time of day, male density, and male diet. Super Q was found to be a superior adsorbent for the male-produced alcohols and geranic acid as well as the plant-produced E-β-ocimene. Pheromone production increased with male age up to about age 15 days old and then tapered off. Male pepper weevils produced the highest amount of pheromone between noon and 2 pm (i.e., 4 to 6 h after “lights on” and were producing ca. 800 ng/h during this period. Thereafter, pheromone production decreased and was extremely low during the scotophase (i.e., ca. 12 ng/h. Male pepper weevil density had a significant effect on both release rate and pheromone composition. Pheromone production on a per male basis was highest for individual males and the percentage of geranic acid in the blend was lowest for individual males. Male pepper weevils produced only extremely low amounts of pheromone when feeding on artificial diet; however, they produced very high amounts when on fresh peppers. Together, this information will be useful in designing better attractant lures for pepper weevils.

  6. Modeling of pheromone communication system of forest Lepidopterous insects. II. Model of female searching by male

    Directory of Open Access Journals (Sweden)

    A. V. Kovalev

    2015-06-01

    Full Text Available We propose an agent­based simulation model search. This model allows us to evaluate the effectiveness of different males­females pheromone search strategies for Lepidoptera. In the model, we consider the simplest case of the search, when the pheromone has only one chemical component. It is assumed that the insects are able to detect the pheromone molecules and the sensory cells generate action potentials in contact with the pheromone for some time. Thereafter pheromone molecule is inactivated. This behavior can be regarded as a memory of individual. Proportion of individuals who have reached the source is selected as an integral indicator of the search efficiency. To evaluate the effectiveness, numeric experiments were performed in different conditions: random walk, search algorithm without memory, and algorithm with memory and return mechanism. The resulting effectiveness of source localization by insects for flight in turbulent flows is ~ 70 %, which corresponds to experiments with live specimens in literature. In this case, proposed pheromone search algorithm is quite simple, which makes it biologically correct. Conducted modeling calculations can be the starting point for planning of field observations and pest monitoring systems using pheromone traps.

  7. Co-option and evolution of non-olfactory proteinaceous pheromones in a terrestrial lungless salamander.

    Science.gov (United States)

    Doty, Kari A; Wilburn, Damien B; Bowen, Kathleen E; Feldhoff, Pamela W; Feldhoff, Richard C

    2016-03-01

    Gene co-option is a major force in the evolution of novel biological functions. In plethodontid salamanders, males deliver proteinaceous courtship pheromones to the female olfactory system or transdermally to the bloodstream. Molecular studies identified three families of highly duplicated, rapidly evolving pheromones (PRF, PMF, and SPF). Analyses for Plethodon salamanders revealed pheromone mixtures of primarily PRF and PMF. The current study demonstrates that in Desmognathus ocoee--a plesiomorphic species with transdermal delivery--SPF is the major pheromone component representing >30% of total protein. Chromatographic profiles of D. ocoee pheromones were consistent from May through October. LC/MS-MS analysis suggested uniform SPF isoform expression between individual male D. ocoee. A gene ancestry for SPF with the Three-Finger Protein superfamily was supported by intron-exon boundaries, but not by the disulfide bonding pattern. Further analysis of the pheromone mixture revealed paralogs to peptide hormones that contained mutations in receptor binding regions, such that these novel molecules may alter female physiology by acting as hormone agonists/antagonists. Cumulatively, gene co-option, duplication, and neofunctionalization have permitted recruitment of additional gene families for pheromone activity. Such independent co-option events may be playing a key role in salamander speciation by altering male traits that influence reproductive success.

  8. Genes involved in sex pheromone discrimination in Drosophila melanogaster and their background-dependent effect.

    Directory of Open Access Journals (Sweden)

    Benjamin Houot

    Full Text Available Mate choice is based on the comparison of the sensory quality of potential mating partners, and sex pheromones play an important role in this process. In Drosophila melanogaster, contact pheromones differ between male and female in their content and in their effects on male courtship, both inhibitory and stimulatory. To investigate the genetic basis of sex pheromone discrimination, we experimentally selected males showing either a higher or lower ability to discriminate sex pheromones over 20 generations. This experimental selection was carried out in parallel on two different genetic backgrounds: wild-type and desat1 mutant, in which parental males showed high and low sex pheromone discrimination ability respectively. Male perception of male and female pheromones was separately affected during the process of selection. A comparison of transcriptomic activity between high and low discrimination lines revealed genes not only that varied according to the starting genetic background, but varied reciprocally. Mutants in two of these genes, Shaker and quick-to-court, were capable of producing similar effects on discrimination on their own, in some instances mimicking the selected lines, in others not. This suggests that discrimination of sex pheromones depends on genes whose activity is sensitive to genetic context and provides a rare, genetically defined example of the phenomenon known as "allele flips," in which interactions have reciprocal effects on different genetic backgrounds.

  9. Natural variation in dauer pheromone production and sensing supports intraspecific competition in nematodes.

    Science.gov (United States)

    Bose, Neelanjan; Meyer, Jan M; Yim, Joshua J; Mayer, Melanie G; Markov, Gabriel V; Ogawa, Akira; Schroeder, Frank C; Sommer, Ralf J

    2014-07-07

    Dauer formation, a major nematode survival strategy, represents a model for small-molecule regulation of metazoan development [1-10]. Free-living nematodes excrete dauer-inducing pheromones that have been assumed to target conspecifics of the same genotype [9, 11]. However, recent studies in Pristionchus pacificus revealed that the dauer pheromone of some strains affects conspecifics of other genotypes more strongly than individuals of the same genotype [12]. To elucidate the mechanistic basis for this intriguing cross-preference, we compared six P. pacificus wild isolates to determine the chemical composition of their dauer-inducing metabolomes and responses to individual pheromone components. We found that these isolates produce dauer pheromone blends of different composition and respond differently to individual pheromone components. Strikingly, there is no correlation between production of and dauer response to a specific compound in individual strains. Specifically, pheromone components that are abundantly produced by one genotype induce dauer formation in other genotypes, but not necessarily in the abundant producer. Furthermore, some genotypes respond to pheromone components they do not produce themselves. These results support a model of intraspecific competition in nematode dauer formation. Indeed, we observed intraspecific competition among sympatric strains in a novel experimental assay, suggesting a new role of small molecules in nematode ecology.

  10. Demonstration and Characterization of a Persistent Pheromone Lure for the Navel Orangeworm, Amyelois transitella (Lepidoptera: Pyralidae

    Directory of Open Access Journals (Sweden)

    Bradley S. Higbee

    2014-07-01

    Full Text Available The lack of an effective pheromone lure has made it difficult to monitor and manage the navel orangeworm, Amyelois transitella (Lepidoptera: Pyralidae, in the economically important crops in which it is the primary insect pest. A series of experiments was conducted to demonstrate and characterize a practical synthetic pheromone lure for capturing navel orangeworm males. Traps baited with lures prepared with 1 or 2 mg of a three- or four-component formulation captured similar numbers of males. The fluctuation over time in the number of males captured in traps baited with the pheromone lure correlated significantly with males captured in female-baited traps. Traps baited with the pheromone lure usually did not capture as many males as traps baited with unmated females, and the ratio of males trapped with pheromone to males trapped with females varied between crops and with abundance. The pheromone lure described improves the ability of pest managers to detect and monitor navel orangeworm efficiently and may improve management and decrease insecticide treatments applied as a precaution against damage. Awareness of differences between male interaction with the pheromone lure and calling females, as shown in these data, will be important as further studies and experience determine how best to use this lure for pest management.

  11. Functional characterization of sex pheromone receptors in the purple stem borer, Sesamia inferens (Walker).

    Science.gov (United States)

    Zhang, Y-N; Zhang, J; Yan, S-W; Chang, H-T; Liu, Y; Wang, G-R; Dong, S-L

    2014-10-01

    The sex pheromone communication system in moths is highly species-specific and extremely sensitive, and pheromone receptors (PRs) are thought to be the most important factors in males. In the present study, three full-length cDNAs encoding PRs were characterized from Sesamia inferens antennae. These three PRs were all male-specific in expression, but their relative expression levels were very different; SinfOR29 was 17- to 23-fold higher than the other two PRs. Phylogenetic and motif pattern analyses showed that these three PRs were allocated to different PR subfamilies with different motif patterns. Functional analysis using the heterologous expression system of Xenopus oocytes demonstrated that SinfOR29 specifically and sensitively responded to the major pheromone component, Z11-16:OAc [concentration for 50% of maximal effect (EC50 ) = 3.431 × 10(-7) M], while SinfOR21 responded robustly to a minor pheromone component Z11-16:OH (EC50  = 1.087 × 10(-6) M). SinfOR27, however, displayed no response to any of the three pheromone components, but, interestingly, it was sensitive to a non-sex pheromone component Z9,E12-14:OAc (EC50  = 1.522 × 10(-6) M). Our results provide insight into the molecular mechanisms of specificity and sensitivity of the sex pheromone communication system in moths.

  12. A potent dauer pheromone component in Caenorhabditis elegans that acts synergistically with other components.

    Science.gov (United States)

    Butcher, Rebecca A; Ragains, Justin R; Kim, Edward; Clardy, Jon

    2008-09-23

    In the model organism Caenorhabditis elegans, the dauer pheromone is the primary cue for entry into the developmentally arrested, dauer larval stage. The dauer is specialized for survival under harsh environmental conditions and is considered "nonaging" because larvae that exit dauer have a normal life span. C. elegans constitutively secretes the dauer pheromone into its environment, enabling it to sense its population density. Several components of the dauer pheromone have been identified as derivatives of the dideoxy sugar ascarylose, but additional unidentified components of the dauer pheromone contribute to its activity. Here, we show that an ascaroside with a 3-hydroxypropionate side chain is a highly potent component of the dauer pheromone that acts synergistically with previously identified components. Furthermore, we show that the active dauer pheromone components that are produced by C. elegans vary depending on cultivation conditions. Identifying the active components of the dauer pheromone, the conditions under which they are produced, and their mechanisms of action will greatly extend our understanding of how chemosensory cues from the environment can influence such fundamental processes as development, metabolism, and aging in nematodes and in higher organisms.

  13. Plant odorants interfere with detection of sex pheromone signals by male Heliothis virescens

    Directory of Open Access Journals (Sweden)

    Pablo ePregitzer

    2012-10-01

    Full Text Available In many insects, mate finding relies on female-released sex pheromones, which have to be deciphered by the male olfactory system within an odorous background of plant volatiles present in the environment of a calling female. With respect to pheromone-mediated mate localization, plant odorants may be neutral, favorable or disturbing. Here we examined the impact of plant odorants on detection and coding of the major sex pheromone component, (Z-11-hexadecenal (Z11-16:Ald in the noctuid moth Heliothis virescens. By in vivo imaging the activity in the male antennal lobe, we monitored the interference at the level of olfactory sensory neurons (OSN to illuminate mixture interactions. The results show that stimulating the male antenna with Z11-16:Ald and distinct plant-related odorants simultaneously suppressed pheromone-evoked activity in the region of the macroglomerular complex (MGC, where Z11-16:Ald-specific OSNs terminate. Based on our previous findings that antennal detection of Z11-16:Ald involves an interplay of the pheromone binding protein HvirPBP2 and the pheromone receptor HR13, we asked if the plant odorants may interfere with any of the elements involved in pheromone detection. Using a competitive fluorescence binding assay, we found that the plant odorants neither bind to HvirPBP2 nor affect the binding of Z11-16:Ald to the protein. However, imaging experiments analyzing a cell line that expressed the receptor HR13 revealed that plant odorants significantly inhibited the Z11-16:Ald-evoked calcium responses. Together the results indicate that, plant odorants can interfere with the signaling process of the major sex pheromone component at the receptor level. Consequently, it can be assumed that plant odorants in the environment may reduce the firing activity of pheromone-specific OSNs in H. virescens and thus affect mate localization.

  14. The Influence of Host Plant Volatiles on the Attraction of Longhorn Beetles to Pheromones.

    Science.gov (United States)

    Collignon, R Maxwell; Swift, Ian P; Zou, Yunfan; McElfresh, J Steven; Hanks, Lawrence M; Millar, Jocelyn G

    2016-03-01

    Host plant volatiles have been shown to strongly synergize the attraction of some longhorn beetle species (Coleoptera: Cerambycidae) to their pheromones. This synergism is well documented among species that infest conifers, but less so for angiosperm-infesting species. To explore the extent of this phenomenon in the Cerambycidae, we first tested the responses of a cerambycid community to a generic pheromone blend in the presence or absence of chipped material from host plants as a source of host volatiles. In the second phase, blends of oak and conifer volatiles were reconstructed, and tested at low, medium, and high release rates with the pheromone blend. For conifer-infesting species in the subfamilies Spondylidinae and Lamiinae, conifer volatiles released at the high rate synergized attraction of some species to the pheromone blend. When comparing high-release rate conifer blend with high-release rate α-pinene as a single component, species responses varied, with Asemum nitidum LeConte being most attracted to pheromones plus α-pinene, whereas Neospondylis upiformis (Mannerheim) were most attracted to pheromones plus conifer blend and ethanol. For oak-infesting species in the subfamily Cerambycinae, with the exception of Phymatodes grandis Casey, which were most attracted to pheromones plus ethanol, neither synthetic oak blend nor ethanol increased attraction to pheromones. The results indicate that the responses to combinations of pheromones with host plant volatiles varied from synergistic to antagonistic, depending on beetle species. Release rates of host plant volatiles also were important, with some high release rates being antagonistic for oak-infesting species, but acting synergistically for conifer-infesting species.

  15. Interference of plant volatiles on pheromone receptor neurons of male Grapholita molesta (Lepidoptera: Tortricidae).

    Science.gov (United States)

    Ammagarahalli, Byrappa; Gemeno, César

    2015-10-01

    In moths, sex pheromone components are detected by pheromone-specific olfactory receptor neurons (ph-ORNs) housed in sensilla trichodea in the male antennae. In Grapholita molesta, ph-ORNs are highly sensitive and specific to the individual sex pheromone components, and thus help in the detection and discrimination of the unique conspecific pheromone blend. Plant odors interspersed with a sub-optimal pheromone dose are reported to increase male moth attraction. To determine if the behavioral synergism of pheromone and plant odors starts at the ph-ORN level, single sensillum recordings were performed on Z8-12:Ac and E8-12:Ac ph-ORNs (Z-ORNs and E-ORNs, respectively) stimulated with pheromone-plant volatile mixtures. First, biologically meaningful plant-volatile doses were determined by recording the response of plant-specific ORNs housed in sensilla auricillica and trichodea to several plant odorants. This exploration provided a first glance at plant ORNs in this species. Then, using these plant volatile doses, we found that the spontaneous activity of ph-ORNs was not affected by the stimulation with plant volatiles, but that a binary mixture of sex pheromone and plant odorants resulted in a small (about 15%), dose-independent, but statistically significant, reduction in the spike frequency of Z-ORNs with respect to stimulation with Z8-12:Ac alone. The response of E-ORNs to a combination of E8-12:Ac and plant volatiles was not different from E8-12:Ac alone. We argue that the small inhibition of Z-ORNs caused by physiologically realistic plant volatile doses is probably not fully responsible for the observed behavioral synergism of pheromone and plant odors.

  16. Identification and functional characterization of sex pheromone receptors in the common cutworm (Spodoptera litura).

    Science.gov (United States)

    Zhang, Jin; Yan, Shuwei; Liu, Yang; Jacquin-Joly, Emmanuelle; Dong, Shuanglin; Wang, Guirong

    2015-01-01

    Male moths can finely discriminate the sex pheromone emitted by conspecific females from similar compounds. Pheromone receptors, expressed on the dendritic membrane of sensory neurons housed in the long trichoid sensilla of antennae, are thought to be associated with the pheromone reception. In this study, we identified and functionally characterized 4 pheromone receptors from the antennae of Spodoptera litura (Lepidoptera: Noctuidae). A tissue distribution analysis showed that the expression of the 4 SlituPRs was restricted to antennae. In addition, SlituOR6 and SlituOR13 were specifically expressed in male antennae whereas SlituOR11 and SlituOR16 were male-biased. Functional investigation by heterologous expression in Xenopus oocytes revealed that SlituOR6 was specifically tuned to the second major pheromone component, Z9,E12-14:OAc, SlituOR13 was equally tuned to Z9,E12-14:OAc and Z9-14:OAc, with a small response to the major pheromone component Z9,E11-14:OAc, SlituOR16 significantly responded to the behavioral antagonist Z9-14:OH, whereas SlituOR11 did not show response to any of the pheromone compounds tested in this study. Our results provide molecular data to better understand the mechanisms of sex pheromone detection in the moth S. litura and bring clues to investigate the evolution of the sexual communication channel in closely related species through comparison with previously reported pheromone receptors in other Spodoptera species.

  17. Genetic mapping of male pheromone response in the European corn borer identifies candidate genes regulating neurogenesis

    Science.gov (United States)

    Dekker, Teun; Heckel, David G.

    2016-01-01

    The sexual pheromone communication system of moths is a model system for studies of the evolution of reproductive isolation. Females emit a blend of volatile components that males detect at a distance. Species differences in female pheromone composition and male response directly reinforce reproductive isolation in nature, because even slight variations in the species-specific pheromone blend are usually rejected by the male. The mechanisms by which a new pheromone signal–response system could evolve are enigmatic, because any deviation from the optimally attractive blend should be selected against. Here we investigate the genetic mechanisms enabling a switch in male response. We used a quantitative trait locus-mapping approach to identify the genetic basis of male response in the two pheromone races of the European corn borer, Ostrinia nubilalis. Male response to a 99:1 vs. a 3:97 ratio of the E and Z isomers of the female pheromone is governed by a single, sex-linked locus. We found that the chromosomal region most tightly linked to this locus contains genes involved in neurogenesis but, in accordance with an earlier study, does not contain the odorant receptors expressed in the male antenna that detect the pheromone. This finding implies that differences in the development of neuronal pathways conveying information from the antenna, not differences in pheromone detection by the odorant receptors, are primarily responsible for the behavioral response differences among the males in this system. Comparison with other moth species reveals a previously unexplored mechanism by which male pheromone response can change in evolution. PMID:27698145

  18. Beyond species recognition: somatic state affects long-distance sex pheromone communication.

    Science.gov (United States)

    Chemnitz, Johanna; Jentschke, Petra C; Ayasse, Manfred; Steiger, Sandra

    2015-08-07

    Long-range sex pheromones have been subjected to substantial research with a particular focus on their biosynthesis, peripheral perception, central processing and the resulting orientation behaviour of perceivers. Fundamental to the research on sex attractants was the assumption that they primarily coordinate species recognition. However, especially when they are produced by the less limiting sex (usually males), the evolution of heightened condition dependence might be expected and long-range sex pheromones might, therefore, also inform about a signaller's quality. Here we provide, to our knowledge, the first comprehensive study of the role of a male's long-range pheromone in mate choice that combines chemical analyses, video observations and field experiments with a multifactorial manipulation of males' condition. We show that the emission of the long-distance sex pheromone of the burying beetle, Nicrophorus vespilloides is highly condition-dependent and reliably reflects nutritional state, age, body size and parasite load--key components of an individual's somatic state. Both, the quantity and ratio of the pheromone components were affected but the time invested in pheromone emission was largely unaffected by a male's condition. Moreover, the variation in pheromone emission caused by the variation in condition had a strong effect on the attractiveness of males in the field, with males in better nutritional condition, of older age, larger body size and bearing less parasites being more attractive. That a single pheromone is influenced by so many aspects of the somatic state and causes such variation in a male's attractiveness under field conditions was hitherto unknown and highlights the need to integrate indicator models of sexual selection into pheromone research.

  19. Discrimination of cis-trans sex pheromone components in two sympatric Lepidopteran species.

    Science.gov (United States)

    Zhang, Sufang; Kong, Xiangbo; Ze, Sangzi; Wang, Hongbin; Lin, Aizhu; Liu, Fu; Zhang, Zhen

    2016-06-01

    Pheromone-binding proteins (PBPs) play an important role in the recognition of pheromones by insects. However, the abilities of these PBPs to discriminate pheromone components and recognize the isomers are unclear. Dendrolimus houi and Dendrolimus kikuchii are two sympatric coniferous pests whose pheromones have cis-trans isomers. We used these insect species to detect the precise recognition abilities of PBPs. The four PBPs examined showed male-biased antenna-intensive expression patterns, whereas PBP1 showed higher expression than PBP2 in the antenna. DhouPBP1 only bound to a minor interspecific pheromone component, whereas DhouPBP2 bound to all three intraspecific components and another minor interspecific component. DkikPBP1 and DkikPBP2 could recognize all three intraspecific components with affinities negatively correlated with their ratios, and they bound to interspecific pheromones with affinity that was positively correlated with the ratios. The four PBPs have different cis-trans isomer discrimination abilities, i.e., DhouPBP1 and DkikPBP1 could not discriminate the two cis-trans isomer pairs of pheromones from the two species, whereas DhouPBP2 could discriminate between both pairs, and DkikPBP2 could only discriminate one pair. Overall, PBPs from D. houi and D. kikuchii use different strategies to help the moths to discriminate the intra- and interspecific pheromone components. Our work will contribute to better understanding of the sex pheromone recognition mechanism in these two sister species of moths and provide insights into more effective management practices of these pest species.

  20. The reproductive ability of Varroa destructor in worker brood of Africanized and hybrid honey bees in Costa Rica

    NARCIS (Netherlands)

    Calderon, R.A.; Sommeijer, M.J.; Ruijter, de A.; Veen, van der J.W.

    2003-01-01

    From February to July 2001, the reproductive ability of Varroa destructor in artificially infested worker brood cells of Africanized honey bees (AHB) (Apis mellifera) and hybrids (HF1) of AHB x European honey bees was investigated in Costa Rica. No significant differences were found between AHB and

  1. Deep-sea octopus (Graneledone boreopacifica) conducts the longest-known egg-brooding period of any animal.

    Science.gov (United States)

    Robison, Bruce; Seibel, Brad; Drazen, Jeffrey

    2014-01-01

    Octopuses typically have a single reproductive period and then they die (semelparity). Once a clutch of fertilized eggs has been produced, the female protects and tends them until they hatch. In most shallow-water species this period of parental care can last from 1 to 3 months, but very little is known about the brooding of deep-living species. In the cold, dark waters of the deep ocean, metabolic processes are often slower than their counterparts at shallower depths. Extrapolations from data on shallow-water octopus species suggest that lower temperatures would prolong embryonic development periods. Likewise, laboratory studies have linked lower temperatures to longer brooding periods in cephalopods, but direct evidence has not been available. We found an opportunity to directly measure the brooding period of the deep-sea octopus Graneledone boreopacifica, in its natural habitat. At 53 months, it is by far the longest egg-brooding period ever reported for any animal species. These surprising results emphasize the selective value of prolonged embryonic development in order to produce competitive hatchlings. They also extend the known boundaries of physiological adaptations for life in the deep sea.

  2. How Much of Language, If Any, Came About in the Same Sort of Way as the Brooding Chamber in Snails?

    Science.gov (United States)

    Botha, Rudolf P.

    2001-01-01

    Critically assesses the merits and limitations of four conceptions of language genesis. Focuses on the conception that language, like the brooding chamber in certain snail species, came about through cooption as a by-product of something else. (Author/VWL)

  3. Use of lactobacilli and their pheromone-based regulatory mechanism in gene expression and drug delivery.

    Science.gov (United States)

    Diep, D B; Mathiesen, G; Eijsink, V G H; Nes, I F

    2009-01-01

    Lactobacilli are common microorganisms in diverse vegetables and meat products and several of these are also indigenous inhabitants in the gastro-intestinal (GI) tract of humans and animals where they are believed to have health promoting effects on the host. One of the highly appreciated probiotic effects is their ability to inhibit the growth of pathogens by producing antimicrobial peptides, so-called bacteriocins. Production of some bacteriocins has been shown to be strictly regulated through a quorum-sensing based mechanism mediated by a secreted peptide-pheromone (also called induction peptide; IP), a membrane-located sensor (histidine protein kinase; HPK) and a cytoplasmic response regulator (RR). The interaction between an IP and its sensor, which is highly specific, leads to activation of the cognate RR which in turn binds to regulated promoters and activates gene expression. The HPKs and RRs are built up by conserved modules, and the signalling between them within a network is efficient and directional, and can easily be activated by exogenously added synthetic IPs. Consequently, components from such regulatory networks have successfully been exploited in construction of a number of inducible gene expression systems. In this review, we discuss some well-characterised quorum sensing networks involved in bacteriocin production in lactobacilli, with special focus on the use of the regulatory components in gene expression and on lactobacilli as potential delivery vehicle for therapeutic and vaccine purposes.

  4. Ejaculate of sneaker males is pheromonally inconspicuous in the black goby, Gobius niger (Teleostei, Gobiidae).

    Science.gov (United States)

    Locatello, L; Mazzoldi, C; Rasotto, M B

    2002-11-01

    The black goby, Gobius niger, shows alternative male mating tactics, i.e., parental and sneaker males. Males release a sexual pheromone that attracts females and stimulates aggressive displays in males. This pheromone is produced by the mesorchial gland, a structure well developed in parental males but markedly undeveloped in sneakers. We measured the behavioral response of parental males to the ejaculates of males performing different reproductive tactics. Parental males reacted to the ejaculate of other parental males, with stereotypic aggressive behaviors, but not to the ejaculate of sneakers; consequently sneaker male ejaculate appears to be pheromonally inconspicuous.

  5. Identification and bioassay of sex pheromone components of carob moth,Ectomyelois ceratoniae (Zeller).

    Science.gov (United States)

    Baker, T C; Francke, W; Millar, J G; Löfstedt, C; Hansson, B; Du, J W; Phelan, P L; Vetter, R S; Youngman, R; Todd, J L

    1991-10-01

    Three sex pheromone components of the carob moth were isolated and identified from the extract of female pheromone glands, using a variety of techniques including coupled gas chromatographic-electroantennographic recordings, coupled gas chromatographic-mass spectrometric analysis, microozonolysis, electroantennographic assays of monounsaturated standards, wind-tunnel bioassays, and field trials. The major component was identified as (Z,E)-9,11,13-tetradecatrienal, a novel lepidopterous pheromone component structure. Two minor components, either one of which improves the upwind flight response of males when blended with the major component, were identified as (Z,E)-9,11-tetradecadienal, and (Z)-9-tetra-decenal.

  6. A list of and some comments about the trail pheromones of ants.

    Science.gov (United States)

    Cerdá, Xim; van Oudenhove, Louise; Bernstein, Carlos; Boulay, Raphaël R

    2014-08-01

    Ants use many different chemical compounds to communicate with their nestmates. Foraging success depends on how efficiently ants communicate the presence of food and thus recruit workers to exploit the food resource. Trail pheromones, produced by different exocrine glands, are a key part of ant foraging strategies. By combing through the literature, we compiled a list of the identity and glandular origin of the chemical compounds found in the trail pheromones of 75 different ant species. Of the 168 compounds identified, more than 40% are amines. In the subfamily Myrmicinae, trail pheromones are mostly produced in the venom gland, while in the subfamily Formicinae, they come from the rectal gland.

  7. The shuttling scaffold model for prevention of yeast pheromone pathway misactivation.

    Science.gov (United States)

    Singh, Aditya P; Andries, Erik; Edwards, Jeremy S; Steinberg, Stanly

    2012-12-01

    The molecular scaffold in the yeast pheromone pathway, Ste5, shuttles continuously between the nucleus and the cytoplasm. Ste5 undergoes oligomerization reaction in the nucleus. Upon pheromone stimulation, the Ste5 dimer is rapidly exported out of the nucleus and recruited to the plasma membrane for pathway activation. This clever device on part of the yeast cell is thought to prevent pathway misactivation at high enough levels of Ste5 in the absence of pheromone. We have built a spatiotemporal model of signaling in this pathway to describe its regulation. Our present work underscores the importance of spatial modeling of cell signaling networks to understand their control and functioning.

  8. A putative human pheromone, androstadienone, increases cooperation between men.

    Directory of Open Access Journals (Sweden)

    Paavo Huoviala

    Full Text Available Androstadienone, a component of male sweat, has been suggested to function as a human pheromone, an airborne chemical signal causing specific responses in conspecifics. In earlier studies androstadienone has been reported to increase attraction, affect subjects' mood, cortisol levels and activate brain areas linked to social cognition, among other effects. However, the existing psychological evidence is still relatively scarce, especially regarding androstadienone's effects on male behaviour. The purpose of this study was to look for possible behavioural effects in male subjects by combining two previously distinct branches of research: human pheromone research and behavioural game theory of experimental economics. Forty male subjects participated in a mixed-model, double-blind, placebo-controlled experiment. The participants were exposed to either androstadienone or a control stimulus, and participated in ultimatum and dictator games, decision making tasks commonly used to measure cooperation and generosity quantitatively. Furthermore, we measured participants' salivary cortisol and testosterone levels during the experiment. Salivary testosterone levels were found to positively correlate with cooperative behaviour. After controlling for the effects of participants' baseline testosterone levels, androstadienone was found to increase cooperative behaviour in the decision making tasks. To our knowledge, this is the first study to show that androstadienone directly affects behaviour in human males.

  9. A putative human pheromone, androstadienone, increases cooperation between men.

    Science.gov (United States)

    Huoviala, Paavo; Rantala, Markus J

    2013-01-01

    Androstadienone, a component of male sweat, has been suggested to function as a human pheromone, an airborne chemical signal causing specific responses in conspecifics. In earlier studies androstadienone has been reported to increase attraction, affect subjects' mood, cortisol levels and activate brain areas linked to social cognition, among other effects. However, the existing psychological evidence is still relatively scarce, especially regarding androstadienone's effects on male behaviour. The purpose of this study was to look for possible behavioural effects in male subjects by combining two previously distinct branches of research: human pheromone research and behavioural game theory of experimental economics. Forty male subjects participated in a mixed-model, double-blind, placebo-controlled experiment. The participants were exposed to either androstadienone or a control stimulus, and participated in ultimatum and dictator games, decision making tasks commonly used to measure cooperation and generosity quantitatively. Furthermore, we measured participants' salivary cortisol and testosterone levels during the experiment. Salivary testosterone levels were found to positively correlate with cooperative behaviour. After controlling for the effects of participants' baseline testosterone levels, androstadienone was found to increase cooperative behaviour in the decision making tasks. To our knowledge, this is the first study to show that androstadienone directly affects behaviour in human males.

  10. Taste and pheromone perception in the fruit fly Drosophila melanogaster.

    Science.gov (United States)

    Ebbs, Michelle L; Amrein, Hubert

    2007-08-01

    Taste is an essential sense for detection of nutrient-rich food and avoidance of toxic substances. The Drosophila melanogaster gustatory system provides an excellent model to study taste perception and taste-elicited behaviors. "The fly" is unique in the animal kingdom with regard to available experimental tools, which include a wide repertoire of molecular-genetic analyses (i.e., efficient production of transgenics and gene knockouts), elegant behavioral assays, and the possibility to conduct electrophysiological investigations. In addition, fruit flies, like humans, recognize sugars as a food source, but avoid bitter tasting substances that are often toxic to insects and mammals alike. This paper will present recent research progress in the field of taste and contact pheromone perception in the fruit fly. First, we shall describe the anatomical properties of the Drosophila gustatory system and survey the family of taste receptors to provide an appropriate background. We shall then review taste and pheromone perception mainly from a molecular genetic perspective that includes behavioral, electrophysiological and imaging analyses of wild type flies and flies with genetically manipulated taste cells. Finally, we shall provide an outlook of taste research in this elegant model system for the next few years.

  11. Brain response to putative pheromones in lesbian women.

    Science.gov (United States)

    Berglund, Hans; Lindström, Per; Savic, Ivanka

    2006-05-23

    The progesterone derivative 4,16-androstadien-3-one (AND) and the estrogen-like steroid estra-1,3,5(10),16-tetraen-3-ol (EST) are candidate compounds for human pheromones. In previous positron emission tomography studies, we found that smelling AND and EST activated regions primarily incorporating the sexually dimorphic nuclei of the anterior hypothalamus, that this activation was differentiated with respect to sex and compound, and that homosexual men processed AND congruently with heterosexual women rather than heterosexual men. These observations indicate involvement of the anterior hypothalamus in physiological processes related to sexual orientation in humans. We expand the information on this issue in the present study by performing identical positron emission tomography experiments on 12 lesbian women. In contrast to heterosexual women, lesbian women processed AND stimuli by the olfactory networks and not the anterior hypothalamus. Furthermore, when smelling EST, they partly shared activation of the anterior hypothalamus with heterosexual men. These data support our previous results about differentiated processing of pheromone-like stimuli in humans and further strengthen the notion of a coupling between hypothalamic neuronal circuits and sexual preferences.

  12. Interactions between aggression, boldness and shoaling within a brood of convict cichlids (Amatitlania nigrofasciatus).

    Science.gov (United States)

    Moss, Sarah; Tittaferrante, Stephanie; Way, Gregory P; Fuller, Ashlei; Sullivan, Nicole; Ruhl, Nathan; McRobert, Scott P

    2015-12-01

    A behavioral syndrome is considered present when individuals consistently express correlated behaviors across two or more axes of behavior. These axes of behavior are shy-bold, exploration-avoidance, activity, aggression, and sociability. In this study we examined aggression, boldness and sociability (shoaling) within a juvenile convict cichlid brood (Amatitlania nigrofasciatus). Because young convict cichlids are social, we used methodologies commonly used by ethologists studying social fishes. We did not detect an aggression-boldness behavioral syndrome, but we did find that the aggression, boldness, and possibly the exploration behavioral axes play significant roles in shaping the observed variation in individual convict cichlid behavior. While juvenile convict cichlids did express a shoaling preference, this social preference was likely convoluted by aggressive interactions, despite the small size and young age of the fish. There is a need for the development of behavioral assays that allow for more reliable measurement of behavioral axes in juvenile neo-tropical cichlids.

  13. Sex allocation in relation to host races in the brood-parasitic common cuckoo (Cuculus canorus.

    Directory of Open Access Journals (Sweden)

    Frode Fossøy

    Full Text Available Sex allocation theory and empirical evidence both suggest that natural selection should favour maternal control of offspring sex ratio in relation to their ability to invest in the offspring. Generalist parasites constitute a particularly interesting group to test this theory as different females commonly utilize different host species showing large variation in provisioning ability. The common cuckoo (Cuculus canorus is a generalist brood parasite that lays its eggs in the nest of many different passerine birds, but each female tends to specialize on one particular host species giving rise to highly specialized host races. The different host species show large variation in their ability to invest in the parasitic offspring, presenting an opportunity for female cuckoos to bias offspring sex ratio in relation to host species quality. Here, we investigate host-race specific sex allocation controlling for maternal identity in the common cuckoo. We found no evidence of any significant relationship between host race and sex ratio in one sympatric population harbouring three different host races, or in a total of five geographically separated populations. There was also no significant association between host quality, as determined by species-specific female host body mass, and cuckoo sex ratio. Finally, we found no significant relationship between individual cuckoo maternal quality, as determined by her egg volume, and sex ratio within each host race. We conclude that the generalist brood-parasitic common cuckoo show no significant sex-ratio bias in relation to host race and discuss this finding in light of gene flow and host adaptations.

  14. Sex allocation in relation to host races in the brood-parasitic common cuckoo (Cuculus canorus).

    Science.gov (United States)

    Fossøy, Frode; Moksnes, Arne; Røskaft, Eivin; Antonov, Anton; Dyrcz, Andrzej; Moskat, Csaba; Ranke, Peter S; Rutila, Jarkko; Vikan, Johan R; Stokke, Bård G

    2012-01-01

    Sex allocation theory and empirical evidence both suggest that natural selection should favour maternal control of offspring sex ratio in relation to their ability to invest in the offspring. Generalist parasites constitute a particularly interesting group to test this theory as different females commonly utilize different host species showing large variation in provisioning ability. The common cuckoo (Cuculus canorus) is a generalist brood parasite that lays its eggs in the nest of many different passerine birds, but each female tends to specialize on one particular host species giving rise to highly specialized host races. The different host species show large variation in their ability to invest in the parasitic offspring, presenting an opportunity for female cuckoos to bias offspring sex ratio in relation to host species quality. Here, we investigate host-race specific sex allocation controlling for maternal identity in the common cuckoo. We found no evidence of any significant relationship between host race and sex ratio in one sympatric population harbouring three different host races, or in a total of five geographically separated populations. There was also no significant association between host quality, as determined by species-specific female host body mass, and cuckoo sex ratio. Finally, we found no significant relationship between individual cuckoo maternal quality, as determined by her egg volume, and sex ratio within each host race. We conclude that the generalist brood-parasitic common cuckoo show no significant sex-ratio bias in relation to host race and discuss this finding in light of gene flow and host adaptations.

  15. Bacterial Respiration and Growth Rates Affect the Feeding Preferences, Brood Size and Lifespan of Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Li Yu

    Full Text Available Bacteria serve as live food and nutrients for bacterial-feeding nematodes (BFNs in soils, and influence nematodes behavior and physiology through their metabolism. Five bacterial taxa (Bacillus amyloliquefaciens JX1, Variovorax sp. JX14, Bacillus megaterium JX15, Pseudomonas fluorescens Y1 and Escherichia coli OP50 and the typical BFN Caenorhabditis elegans were selected to study the effects of bacterial respiration and growth rates on the feeding preferences, brood size and lifespan of nematodes. P. fluorescens Y1 and E. coli OP50 were found to be more active, with high respiration and rapid growth, whereas B. amyloliquefaciens JX1 and B. megaterium JX15 were inactive. The nematode C. elegans preferred active P. fluorescens Y1 and E. coli OP50 obviously. Furthermore, worms that fed on these two active bacteria produced more offspring but had shorter lifespan, while inactive and less preferred bacteria had increased nematodes lifespan and decreased the brood size. Based on these results, we propose that the bacterial activity may influence the behavior and life traits of C. elegans in the following ways: (1 active bacteria reproduce rapidly and emit high levels of CO2 attracting C. elegans; (2 these active bacteria use more resources in the nematodes' gut to sustain their survival and reproduction, thereby reducing the worm's lifespan; (3 inactive bacteria may provide less food for worms than active bacteria, thus increasing nematodes lifespan but decreasing their fertility. Nematodes generally require a balance between their preferred foods and beneficial foods, only preferred food may not be beneficial for nematodes.

  16. Bacterial Respiration and Growth Rates Affect the Feeding Preferences, Brood Size and Lifespan of Caenorhabditis elegans.

    Science.gov (United States)

    Yu, Li; Yan, Xiaomei; Ye, Chenglong; Zhao, Haiyan; Chen, Xiaoyun; Hu, Feng; Li, Huixin

    2015-01-01

    Bacteria serve as live food and nutrients for bacterial-feeding nematodes (BFNs) in soils, and influence nematodes behavior and physiology through their metabolism. Five bacterial taxa (Bacillus amyloliquefaciens JX1, Variovorax sp. JX14, Bacillus megaterium JX15, Pseudomonas fluorescens Y1 and Escherichia coli OP50) and the typical BFN Caenorhabditis elegans were selected to study the effects of bacterial respiration and growth rates on the feeding preferences, brood size and lifespan of nematodes. P. fluorescens Y1 and E. coli OP50 were found to be more active, with high respiration and rapid growth, whereas B. amyloliquefaciens JX1 and B. megaterium JX15 were inactive. The nematode C. elegans preferred active P. fluorescens Y1 and E. coli OP50 obviously. Furthermore, worms that fed on these two active bacteria produced more offspring but had shorter lifespan, while inactive and less preferred bacteria had increased nematodes lifespan and decreased the brood size. Based on these results, we propose that the bacterial activity may influence the behavior and life traits of C. elegans in the following ways: (1) active bacteria reproduce rapidly and emit high levels of CO2 attracting C. elegans; (2) these active bacteria use more resources in the nematodes' gut to sustain their survival and reproduction, thereby reducing the worm's lifespan; (3) inactive bacteria may provide less food for worms than active bacteria, thus increasing nematodes lifespan but decreasing their fertility. Nematodes generally require a balance between their preferred foods and beneficial foods, only preferred food may not be beneficial for nematodes.

  17. Obligate brood parasites show more functionally effective innate immune responses: an eco-immunological hypothesis

    Science.gov (United States)

    Hahn, D. Caldwell; Summers, Scott G.; Genovese, Kenneth J.; He, Haiqi; Kogut, Michael H.

    2013-01-01

    Immune adaptations of obligate brood parasites attracted interest when three New World cowbird species (Passeriformes, Icteridae, genus Molothrus) proved unusually resistant to West Nile virus. We have used cowbirds as models to investigate the eco-immunological hypothesis that species in parasite-rich environments characteristically have enhanced immunity as a life history adaptation. As part of an ongoing program to understand the cowbird immune system, in this study we measured degranulation and oxidative burst, two fundamental responses of the innate immune system. Innate immunity provides non-specific, fast-acting defenses against a variety of invading pathogens, and we hypothesized that innate immunity experiences particularly strong selection in cowbirds, because their life history strategy exposes them to diverse novel and unpredictable parasites. We compared the relative effectiveness of degranulation and oxidative burst responses in two cowbird species and one related, non-parasitic species. Both innate immune defenses were significantly more functionally efficient in the two parasitic cowbird species than in the non-parasitic red-winged blackbird (Icteridae, Agelaius phoeniceus). Additionally, both immune defenses were more functionally efficient in the brown-headed cowbird (M. ater), an extreme host-generalist brood parasite, than in the bronzed cowbird (M. aeneus), a moderate host-specialist with lower exposure to other species and their parasites. Thus the relative effectiveness of these two innate immune responses corresponds to the diversity of parasites in the niche of each species and to their relative resistance to WNV. This study is the first use of these two specialized assays in a comparative immunology study of wild avian species.

  18. Comparison of live weight and body measurements of adult brood mares from different genotypes in Hungary

    Directory of Open Access Journals (Sweden)

    Szabolcs Bene

    2014-06-01

    Full Text Available Live weight and 21 body measurements of 110 Thoroughbred, 75 Gidran, 109 Nonius, 97 Hungarian Sport Horse, 172 Hungarian Cold Blooded Horse and 20 Murinsulaner type adult brood mares in 28 studs were evaluated in Hungary. One way ANOVA was used to compare the genotypes. Some body measure indices were determined. Phenotypic correlation coefficients between the live weight and body measurements were estimated. Regression equations were developed to estimate the live weight from body measurements. Significant differences were found between the live weight and 21 body measurements of different genotypes. The rank of the investigated genotypes according to live weight was as follows: Hungarian Cold Blooded Horse (742.1 kg, Murinsulaner type (649.3 kg, Nonius (614.9 kg, Hungarian Sport Horse (600.9 kg, Gidran (563.4 kg and Thoroughbred (542.0 kg. The results of girth measurements for the warm blooded breeds were similar to the data found in the literature. Considerable difference was found between the genotypes in body measure indices. The absolute and relative body size values prove clearly and objectively, that there are significant differences in the conformation of Thoroughbred, Gidran, Nonius, Hungarian Sport Horse, Hungarian Cold Blooded Horse and Murinsulaner type adult brood mares. The most close relationship with the live weight (r=0.89-0.92; P<0.01 was shown the body condition and nutritional status related measurements (heart girth, 2nd width of rump. For the estimation of live weight with regression model the necessary data are as follows: hearth girth, 2nd width of rump and length of body (R2=0.91; P<0.01.

  19. Experimental evidence for chick discrimination without recognition in a brood parasite host.

    Science.gov (United States)

    Grim, Tomás

    2007-02-01

    Recognition is considered a critical basis for discriminatory behaviours in animals. Theoretically, recognition and discrimination of parasitic chicks are not predicted to evolve in hosts of brood parasitic birds that evict nest-mates. Yet, an earlier study showed that host reed warblers (Acrocephalus scirpaceus) of an evicting parasite, the common cuckoo (Cuculus canorus), can avoid the costs of prolonged care for unrelated young by deserting the cuckoo chick before it fledges. Desertion was not based on specific recognition of the parasite because hosts accept any chick cross-fostered into their nests. Thus, the mechanism of this adaptive host response remains enigmatic. Here, I show experimentally that the cue triggering this 'discrimination without recognition' behaviour is the duration of parental care. Neither the intensity of brood care nor the presence of a single-chick in the nest could explain desertions. Hosts responded similarly to foreign chicks, whether heterospecific or experimental conspecifics. The proposed mechanism of discrimination strikingly differs from those found in other parasite-host systems because hosts do not need an internal recognition template of the parasite's appearance to effectively discriminate. Thus, host defences against parasitic chicks may be based upon mechanisms qualitatively different from those operating against parasitic eggs. I also demonstrate that this discriminatory mechanism is non-costly in terms of recognition errors. Comparative data strongly suggest that parasites cannot counter-evolve any adaptation to mitigate effects of this host defence. These findings have crucial implications for the process and end-result of host-parasite arms races and our understanding of the cognitive basis of discriminatory mechanisms in general.

  20. Ready for a fight? The physiological effects of detecting an opponent's pheromone cues prior to a contest.

    Science.gov (United States)

    Garcia, Mark J; Williams, John; Sinderman, Benjamin; Earley, Ryan L

    2015-10-01

    Reception of pheromone cues can elicit significant physiological (e.g. steroid hormone levels) changes in the recipient. These pheromone-induced physiological changes have been well documented for male-female interactions, but scarcely in same-sex interactions (male-male and female-female). We sought to address this dearth in the current literature and examine whether mangrove rivulus fish (Kryptolebias marmoratus) could detect and, ultimately, mount a physiological response to the pheromone signature of a potential, same-sex competitor. We examined steroid hormone levels in mangrove rivulus exposed to one of three treatments: 1) isolation, 2) exposure to pheromones of a size-matched partner, and 3) pheromone exposure to a size-matched opponent followed by a physical encounter with the opponent. We found that exposure to a competitor's pheromone cues elicited a significant increase in testosterone levels. Increases in testosterone were similar across genetically distinct lineages derived from geographically distinct populations. Further, testosterone levels were similar between individuals only exposed to pheromone cues and individuals exposed to both pheromone cues and a subsequent physical encounter. Our findings led us to generate a number of testable predictions regarding how mangrove rivulus utilize pheromone signals in social interactions, the molecular mechanisms linking social stimuli and hormonal responses, and the possible adaptive benefits of hormonal responsiveness to receiving a potential competitor's pheromone cues.

  1. Reproduction of Varroa destructor and offspring mortality in worker and drone brood cells of Africanized honey bees.

    Science.gov (United States)

    Calderón, R A; Ureña, S; van Veen, J W

    2012-04-01

    Varroa destructor is known to be the most serious parasite of Apis mellifera worldwide. In order to reproduce varroa females enter worker or drone brood shortly before the cell is sealed. From March to December 2008, the reproductive rate and offspring mortality (mature and immature stages), focusing on male absence and male mortality of V. destructor, was investigated in naturally infested worker and drone brood of Africanized honey bees (AHB) in Costa Rica. Data were obtained from 388 to 403 single infested worker and drone brood cells, respectively. Mite fertility in worker and drone brood cells was 88.9 and 93.1%, respectively. There was no difference between the groups (X(2) = 3.6, P = 0.06). However, one of the most significant differences in mite reproduction was the higher percentage of mites producing viable offspring in drone cells (64.8%) compared to worker cells (37.6%) (X(2) = 57.2, P drone cells was high in the protonymph stage (mobile and immobile). A significant finding was the high rate of male mortality. The worker and drone brood revealed that 23.9 and 6.9%, respectively, of the adult male offspring was found dead. If the absence (missing) of the male and adult male mortality are taken together the percentage of cells increased to 40.0 and 21.3% in worker and drone cells, respectively (X(2) = 28.8, P < 0.05). The absence of the male or male mortality in a considerable number of worker cells naturally infested with varroa is the major factor in our study which reduces the production of viable daughters in AHB colonies in Costa Rica.

  2. Individual patterns of habitat and nest-site use by hosts promote transgenerational transmission of avian brood parasitism status.

    Science.gov (United States)

    Hoover, Jeffrey P; Hauber, Mark E

    2007-11-01

    Brood parasitic birds impose variable fitness costs upon their hosts by causing the partial or complete loss of the hosts' own brood. Growing evidence from multiple avian host-parasite taxa indicates that exposure of individual hosts to parasitism is not necessarily random and varies with habitat use, nest-site selection, age or other phenotypic attributes. For instance, nonrandom patterns of brood parasitism had similar evolutionary consequences to those of limited horizontal transmission of parasites and pathogens across space and time and altered the dynamics of both population productivity and co-evolutionary interactions of hosts and parasites. We report that brood parasitism status of hosts of brown-headed cowbirds Molothrus ater is also transmitted across generations in individually colour-banded female prothonotary warblers Protonotaria citrea. Warbler daughters were more likely to share their mothers' parasitism status when showing natal philopatry at the scale of habitat patch. Females never bred in their natal nestboxes but daughters of parasitized mothers had shorter natal dispersal distances than daughters of nonparasitized mothers. Daughters of parasitized mothers were more likely to use nestboxes that had been parasitized by cowbirds in both the previous and current years. Although difficult to document in avian systems, different propensities of vertical transmission of parasitism status within host lineages will have critical implications both for the evolution of parasite tolerance in hosts and, if found to be mediated by lineages of parasites themselves, for the difference in virulence between such extremes as the nestmate-tolerant and nestmate-eliminator strategies of different avian brood parasite species.

  3. A meta-analysis of lesser prairie-chicken nesting and brood-rearing habitats: implications for habitat management

    Science.gov (United States)

    Hagen, Christian A.; Grisham, Blake A.; Boal, Clint W.; Haukos, David A.

    2013-01-01

    The distribution and range of lesser prairie-chicken (Tympanuchus pallidicinctus) has been reduced by >90% since European settlement of the Great Plains of North America. Currently, lesser prairie-chickens occupy 3 general vegetation communities: sand sagebrush (Artemisia filifolia), sand shinnery oak (Quercus havardii), and mixed-grass prairies juxtaposed with Conservation Reserve Program grasslands. As a candidate for protection under the Endangered Species Act, there is a need for a synthesis that characterizes habitat structure rangewide. Thus, we conducted a meta-analysis of vegetation characteristics at nest sites and brood habitats to determine whether there was an overall effect (Hedges' d) of habitat selection and to estimate average (95% CI) habitat characteristics at use sites. We estimated effect sizes (di) from the difference between use (nests and brood sites) and random sampling sites for each study (n = 14), and derived an overall effect size (d++). There was a general effect for habitat selection as evidenced by low levels of variation in effect sizes across studies and regions. There was a small to medium effect (d++) = 0.20-0.82) of selection for greater vertical structure (visual obstruction) by nesting females in both vegetation communities, and selection against bare ground (d++ = 0.20-0.58). Females with broods exhibited less selectivity for habitat components except for vertical structure. The variation of d++ was greater during nesting than brooding periods, signifying a seasonal shift in habitat use, and perhaps a greater range of tolerance for brood-rearing habitat. The overall estimates of vegetation cover were consistent with those provided in management guidelines for the species.

  4. The water-borne protein signals (pheromones) of the Antarctic ciliated protozoan Euplotes nobilii: structure of the gene coding for the En-6 pheromone.

    Science.gov (United States)

    La Terza, Antonietta; Dobri, Nicoleta; Alimenti, Claudio; Vallesi, Adriana; Luporini, Pierangelo

    2009-01-01

    The marine Antarctic ciliate, Euplotes nobilii, secretes a family of water-borne signal proteins, denoted as pheromones, which control vegetative proliferation and mating in the cell. Based on the knowledge of the amino acid sequences of a set of these pheromones isolated from the culture supernatant of wild-type strains, we designed probes to identify their encoding genes in the cell somatic nucleus (macronucleus). The full-length gene of the pheromone En-6 was determined and found to contain an open-reading frame specific for the synthesis of the En-6 cytoplasmic precursor (pre-pro-En-6), which requires 2 proteolytic cleavages to remove the signal peptide (pre) and the prosegment before secretion of the mature protein. In contrast to the sequence variability that distinguishes the secreted pheromones, the pre- and pro-sequences appear to be tightly conserved and useful for the construction of probes to clone every other E. nobilii pheromone gene. Potential intron sequences in the coding region of the En-6 gene imply the synthesis of more En-6 isoforms.

  5. Sex-pairing pheromone in the Asian termite pest species Odontotermes formosanus.

    Science.gov (United States)

    Wen, Ping; Ji, Bao-Zhong; Liu, Shu-Wen; Liu, Cong; Sillam-Dussès, David

    2012-05-01

    The sex-pairing pheromone of the black winged subterranean termite, Odontotermes formosanus (Shiraki) (Isoptera, Termitidae), was investigated using headspace-SPME, GC-MS, GC-EAD, and attraction bioassays. Females secrete the pheromone from their sternal gland to attract males. The sex-pairing pheromone is composed of (Z,Z)-dodeca-3,6-dien-1-ol and (Z)-dodec-3-en-1-ol, estimated at 9 to 16.64 ng and 0.2 to 0.54 ng, respectively. Both short- and long-distance sex attraction bioassays were employed to show that these compounds act in synergy at long distance, but only (Z,Z)-dodeca-3,6-dien-1-ol is active at short distance. The pheromone may be useful in efforts to control this pest, which is considered one of the most harmful termite species in Southeast Asia.

  6. Sex pheromone biosynthesis in the processionary moth Thaumetopoea pityocampa by delta-13 desaturation.

    Science.gov (United States)

    Arsequell, G; Fabriàs, G; Camps, F

    1990-01-01

    In vivo treatments of female sex pheromone glands of the processionary moth, Thaumetopoea pityocampa, with mass-labeled fatty acids showed that (Z)-13-hexadecen-11-ynyl acetate, the main sex pheromone component, is biosynthesized from palmitic acid by the combined action of delta-11 and delta-13 desaturases. The involvement of this unusual delta-13 has been proven by application of [16,16,16-2H3] [1,2-13C2]-hexadecanoic acid to the glands with a resultant incorporation of all labeled atoms into the pheromone and each one of the corresponding intermediates. These results seem to exclude alternative biosynthetic pathways, such as chain shortening and elongation combined with delta-11 desaturation. The delta-11 desaturase responsible for the formation of the triple bond in both the 11-hexadecynoyl and (Z)-13-hexadecen-11-ynoyl intermediates is also an unusual enzyme not previously reported in lepidopteran sex pheromone biosynthesis.

  7. ACaenorhabditis elegans dauer-inducing pheromone and an antagonistic component of the food supply.

    Science.gov (United States)

    Golden, J W; Riddle, D L

    1984-08-01

    The free-living soil nematodeCaenorhabditis elegans forms a nonfeeding dispersal stage at the second molt called the dauer larva when exposed to environmental cues indicating crowding and limited food. An improved bioassay, tenfold more sensitive than that used previously, has been used in the characterization of the two chemical cues which act competitively in controlling this developmental process. The pheromone concentration provides a measure of the population density; it enhances dauer larva formation, and inhibits recovery (exit) from the dauer stage. The pheromone is a family of related molecules which are nonvolatile, very stable, and possess physical and Chromatographie properties similar to those of hydroxylated fatty acids and bile acids. A food signal, with effects on development opposite those of the pheromone, is produced by bacteria, and is also present in yeast extract. In contrast to the pheromone, the food signal is a labile substance which is neutral and hydrophilic.

  8. Are synthetic pheromone captures predictive of parasitoid densities as a kairomonal attracted tool?

    Directory of Open Access Journals (Sweden)

    Mohamed Hassan Bayoumy

    2011-04-01

    Full Text Available Abundance of White Peach scale (WPS, Pseudaulacaspis pentagona (Targioni-Tozzetti and San José scale (SJS, Diaspidiotus perniciosus (Comstock (Hemiptera: Diaspididae adult males and their attracted parasitoids were monitored using pheromone and sticky tape traps in an orchard of Budapest, Hungary, during 2010. In this study, we tried answer on the question raised whether synthetic commercial pheromones of WSP or SJS could work as a kairomonal stimulant and positively attract higher numbers of the specialized parasitoids. Although pheromone traps attracted a wide range of parasitoid species, most of them were accidentally. However, the parasitoid Thomsonisca amathus (Walker (Hymenoptera: E ncyrtidae and the parasitoid Encarsia perniciosi (Tower (Hymenoptera: Aphelinidae significantly respond to the sex pheromones of WPS and SJS, respectively, suggesting that they may play an important role in host location.

  9. Conserved class of queen pheromones stops social insect workers from reproducing.

    Science.gov (United States)

    Van Oystaeyen, Annette; Oliveira, Ricardo Caliari; Holman, Luke; van Zweden, Jelle S; Romero, Carmen; Oi, Cintia A; d'Ettorre, Patrizia; Khalesi, Mohammadreza; Billen, Johan; Wäckers, Felix; Millar, Jocelyn G; Wenseleers, Tom

    2014-01-17

    A major evolutionary transition to eusociality with reproductive division of labor between queens and workers has arisen independently at least 10 times in the ants, bees, and wasps. Pheromones produced by queens are thought to play a key role in regulating this complex social system, but their evolutionary history remains unknown. Here, we identify the first sterility-inducing queen pheromones in a wasp, bumblebee, and desert ant and synthesize existing data on compounds that characterize female fecundity in 64 species of social insects. Our results show that queen pheromones are strikingly conserved across at least three independent origins of eusociality, with wasps, ants, and some bees all appearing to use nonvolatile, saturated hydrocarbons to advertise fecundity and/or suppress worker reproduction. These results suggest that queen pheromones evolved from conserved signals of solitary ancestors.

  10. Ozonolysis of unsaturated compounds in the synthesis of insect pheromones and juvenoids

    Science.gov (United States)

    Ishmuratov, Gumer Yu; Kharisov, Rinat Ya; Odinokov, Viktor N.; Tolstikov, Genrikh A.

    1995-06-01

    The review surveys data on the use of the ozonolysis of cyclic and acyclic monoenes, dienes, and trienes in various stages of the total synthesis of insect pheromones and juvenoids. The bibliography includes 178 references.

  11. Pheromone application in prevention and therapy of domestic animal behavioral disorder

    Directory of Open Access Journals (Sweden)

    Vučinić Marijana

    2007-01-01

    Full Text Available This review-type paper presents the latest knowledge on pheromone therapy. Pheromone therapy does not imply merely the use of structural analogues of pheromones in therapy, but also in the prevention of behavioral disorders in domestic animals. Their application is induced in all cases in which the effects of stressors are expected and their negative effect on the health condition, welfare and production results of domestic animals. Structural analogues of pheromones can successfully be applied in the prevention and therapy of behavioral disorders in horses, swine, dogs, and cats. Recent investigations have confirmed that structural analogues of semiochemicals exert a positive effect also on the production results and meat quality of broilers. They realize their therapeutic and preventive effect on the behavior of domestic animals through the stabilization of the emotional state, relaxation, and calming the animals that are disturbed, or could become disturbed due to the effect of stressors.

  12. Synthesis of the Stereoisomers of the Sex Pheromones of the Southern Corn Rootworm

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A simple and efficient asymmetric synthesis of the sex pheromone of the southern corn rootworm is discribed. The key step is the asymmetric Michael addition of enoylsultam with virtually complete asymmetric induction(e.e.%>99%)

  13. Ovarian steroid sulphate functions as priming pheromone in male Barilius bendelisis (Ham.)

    Indian Academy of Sciences (India)

    J P Bhatt; M S Sajwan

    2001-06-01

    The study reveals that pre-ovulatory females of the fish Barilius bendelisis (Ham.) release sex steroids and their conjugates into the water and that a steroid sulphate of these compounds functions as a potent sex pheromone which stimulates milt production in conspecific males prior to spawning. Since males exposed to the purified sub-fraction III of the steroid sulphate fraction have increased milt volume and more spermatozoa with greater motility, the function of this priming pheromone appears to be to enhance male spawning success. High turbulence and faster water currents render the hillstream ecosystem extremely challenging for chemical communication. Therefore, ovulatory female fish secrete highly water soluble steroid sulphates for rapid pheromonal action in males. Inhibited milt volume in olfactory tract lesioned (OTL) males exposed to the steroid sulphate fraction and 17,20-dihydroxy-4-pregnen-3-one supports the concept that the pheromonally induced priming effect in male fish is mediated through olfactory pathways.

  14. Small-molecule pheromones that control dauer development in Caenorhabditis elegans.

    Science.gov (United States)

    Butcher, Rebecca A; Fujita, Masaki; Schroeder, Frank C; Clardy, Jon

    2007-07-01

    In response to high population density or low food supply, the nematode Caenorhabditis elegans enters an alternative larval stage, known as the dauer, that can withstand adverse conditions for prolonged periods. C. elegans senses its population density through a small-molecule signal, traditionally called the dauer pheromone, that it secretes into its surroundings. Here we show that the dauer pheromone consists of several structurally related ascarosides-derivatives of the dideoxysugar ascarylose-and that two of these ascarosides (1 and 2) are roughly two orders of magnitude more potent at inducing dauer formation than a previously reported dauer pheromone component (3) and constitute a physiologically relevant signal. The identification of dauer pheromone components 1 and 2 will facilitate the identification of target receptors and downstream signaling proteins.

  15. Synthetic sex pheromone attracts the leishmaniasis vector Lutzomyia longipalpis to experimental chicken sheds treated with insecticide

    Directory of Open Access Journals (Sweden)

    Brazil Reginaldo P

    2010-03-01

    Full Text Available Abstract Background Current strategies for controlling American visceral leishmaniasis (AVL have been unable to prevent the spread of the disease across Brazil. With no effective vaccine and culling of infected dogs an unpopular and unsuccessful alternative, new tools are urgently needed to manage populations of the sand fly vector, Lutzomyia longipalpis Lutz and Neiva (Diptera: Psychodidae. Here, we test two potential strategies for improving L. longipalpis control using the synthetic sand fly pheromone (±-9-methylgermacrene-B: the first in conjunction with spraying of animal houses with insecticide, the second using coloured sticky traps. Results Addition of synthetic pheromone resulted in greater numbers of male and female sand flies being caught and killed at experimental chicken sheds sprayed with insecticide, compared to pheromone-less controls. Furthermore, a ten-fold increase in the amount of sex pheromone released from test sheds increased the number of females attracted and subsequently killed. Treating sheds with insecticide alone resulted in a significant decrease in numbers of males attracted to sheds (compared to pre-spraying levels, and a near significant decrease in numbers of females. However, this effect was reversed through addition of synthetic pheromone at the time of insecticide spraying, leading to an increase in number of flies attracted post-treatment. In field trials of commercially available different coloured sticky traps, yellow traps caught more males than blue traps when placed in chicken sheds. In addition, yellow traps fitted with 10 pheromone lures caught significantly more males than pheromone-less controls. However, while female sand flies showed a preference for both blue and yellow pheromone traps sticky traps over white traps in the laboratory, neither colour caught significant numbers of females in chicken sheds, either with or without pheromone. Conclusions We conclude that synthetic pheromone could

  16. Lack of spatial segregation in the representation of pheromones and kairomones in the mouse medial amygdala

    OpenAIRE

    Vinicius Miessler de Andrade Carvalho; Thiago Seike Nakahara; Leonardo Minete Cardozo; Mateus Augusto de Andrade Souza; Antonio Pedro de Castello Branco da Rocha Camargo; Guilherme Ziegler Trintinalia; Eliana eFerraz; Fabio ePapes

    2015-01-01

    The nervous system is organized to detect, internally represent and process sensory information to generate appropriate behaviors. Despite the crucial importance of odors that elicit instinctive behaviors, such as pheromones and kairomones, their neural representation remains little characterized in the mammalian brain. Here we used expression of the immediate early gene product c-Fos as a marker of neuronal activity to find that a wide range of pheromones and kairomones produces activation i...

  17. Factors Affecting Pheromone Production by the Pepper Weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae) and Collection Efficiency

    OpenAIRE

    Eller, Fred; Palmquist,Debra

    2014-01-01

    Several factors affecting pheromone production by male pepper weevils, Anthonomus eugenii Cano (Coleoptera: Curculionidae) as well as collection efficiency were investigated. Factors studied included: porous polymer adsorbents (Tenax versus Super Q), male age, time of day, male density, and male diet. Super Q was found to be a superior adsorbent for the male-produced alcohols and geranic acid as well as the plant-produced E-β-ocimene. Pheromone production increased with male age up to about a...

  18. Factors Affecting Pheromone Production by the Pepper Weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae) and Collection Efficiency

    OpenAIRE

    Eller, Fred J.; Debra E. Palmquist

    2014-01-01

    Several factors affecting pheromone production by male pepper weevils, Anthonomus eugenii Cano (Coleoptera: Curculionidae) as well as collection efficiency were investigated. Factors studied included: porous polymer adsorbents (Tenax versus Super Q), male age, time of day, male density, and male diet. Super Q was found to be a superior adsorbent for the male-produced alcohols and geranic acid as well as the plant-produced E-β-ocimene. Pheromone production increased with male age up to about ...

  19. Addition of alarm pheromone components improves the effectiveness of desiccant dusts against Cimex lectularius.

    Science.gov (United States)

    Benoit, Joshua B; Phillips, Seth A; Croxall, Travis J; Christensen, Brady S; Yoder, Jay A; Denlinger, David L

    2009-05-01

    We demonstrate that the addition of bed bug, Cimex lectularius, alarm pheromone to desiccant formulations greatly enhances their effectiveness during short-term exposure. Two desiccant formulations, diatomaceous earth (DE) and Dri-die (silica gel), were applied at the label rate with and without bed bug alarm pheromone components, (E)-2-hexenal, (E)-2-octenal, and a (E)-2-hexenal:(E)-2-octenal blend. First-instar nymphs and adult females were subjected to 10-min exposures, and water loss rates were used to evaluate the response. Optimal effectiveness was achieved with a pheromone concentration of 0.01 M. With Dri-die alone, the water loss was 21% higher than in untreated controls, and water loss increased nearly two times with (E)-2-hexenal and (E)-2-octenal and three times with the (E)-2-hexenal: (E)-2-octenal blend. This shortened survival of first-instar nymphs from 4 to 1 d, with a similar reduction noted in adult females. DE was effective only if supplemented with pheromone, resulting in a 50% increase in water loss over controls with the (E)-2-hexenal:(E)-2-octenal blend, and a survival decrease from 4 to 2 d in first-instar nymphs. Consistently, the addition of the pheromone blend to desiccant dust was more effective than adding either component by itself or by using Dri-die or DE alone. Based on observations in a small microhabitat, the addition of alarm pheromone components prompted bed bugs to leave their protective harborages and to move through the desiccant, improving the use of desiccants for control. We concluded that short exposure to Dri-die is a more effective treatment against bed bugs than DE and that the effectiveness of the desiccants can be further enhanced by incorporation of alarm pheromone. Presumably, the addition of alarm pheromone elevates excited crawling activity, thereby promoting cuticular changes that increase water loss.

  20. Communication disruption of guava moth (Coscinoptycha improbana) using a pheromone analog based on chain length.

    Science.gov (United States)

    Suckling, D M; Dymock, J J; Park, K C; Wakelin, R H; Jamieson, L E

    2013-09-01

    The guava moth, Coscinoptycha improbana, an Australian species that infests fruit crops in commercial and home orchards, was first detected in New Zealand in 1997. A four-component pheromone blend was identified but is not yet commercially available. Using single sensillum recordings from male antennae, we established that the same olfactory receptor neurons responded to two guava moth sex pheromone components, (Z)-11-octadecen-8-one and (Z)-12-nonadecen-9-one, and to a chain length analog, (Z)-13-eicosen-10-one, the sex pheromone of the related peach fruit moth, Carposina sasakii. We then field tested whether this non-specificity of the olfactory neurons might enable disruption of sexual communication by the commercially available analog, using male catch to synthetic lures in traps in single-tree, nine-tree and 2-ha plots. A disruptive pheromone analog, based on chain length, is reported for the first time. Trap catches for guava moth were disrupted by three polyethylene tubing dispensers releasing the analog in single-tree plots (86% disruption of control catches) and in a plots of nine trees (99% disruption). Where peach fruit moth pheromone dispensers were deployed at a density of 1000/ha in two 2-ha areas, pheromone traps for guava moth were completely disrupted for an extended period (up to 470 days in peri-urban gardens in Mangonui and 422 days in macadamia nut orchards in Kerikeri). In contrast, traps in untreated areas over 100 m away caught 302.8 ± 128.1 moths/trap in Mangonui and 327.5 ± 78.5 moths/ trap in Kerikeri. The longer chain length in the pheromone analog has greater longevity than the natural pheromone due to its lower volatility. Chain length analogs may warrant further investigation for mating disruption in Lepidoptera, and screening using single-sensillum recording is recommended.

  1. Allelic exchange of pheromones and their receptors reprograms sexual identity in Cryptococcus neoformans.

    Science.gov (United States)

    Stanton, Brynne C; Giles, Steven S; Staudt, Mark W; Kruzel, Emilia K; Hull, Christina M

    2010-02-26

    Cell type specification is a fundamental process that all cells must carry out to ensure appropriate behaviors in response to environmental stimuli. In fungi, cell identity is critical for defining "sexes" known as mating types and is controlled by components of mating type (MAT) loci. MAT-encoded genes function to define sexes via two distinct paradigms: 1) by controlling transcription of components common to both sexes, or 2) by expressing specially encoded factors (pheromones and their receptors) that differ between mating types. The human fungal pathogen Cryptococcus neoformans has two mating types (a and alpha) that are specified by an extremely unusual MAT locus. The complex architecture of this locus makes it impossible to predict which paradigm governs mating type. To identify the mechanism by which the C. neoformans sexes are determined, we created strains in which the pheromone and pheromone receptor from one mating type (a) replaced the pheromone and pheromone receptor of the other (alpha). We discovered that these "alpha(a)" cells effectively adopt a new mating type (that of a cells); they sense and respond to alpha factor, they elicit a mating response from alpha cells, and they fuse with alpha cells. In addition, alpha(a) cells lose the alpha cell type-specific response to pheromone and do not form germ tubes, instead remaining spherical like a cells. Finally, we discovered that exogenous expression of the diploid/dikaryon-specific transcription factor Sxi2a could then promote complete sexual development in crosses between alpha and alpha(a) strains. These data reveal that cell identity in C. neoformans is controlled fully by three kinds of MAT-encoded proteins: pheromones, pheromone receptors, and homeodomain proteins. Our findings establish the mechanisms for maintenance of distinct cell types and subsequent developmental behaviors in this unusual human fungal pathogen.

  2. Allelic exchange of pheromones and their receptors reprograms sexual identity in Cryptococcus neoformans.

    Directory of Open Access Journals (Sweden)

    Brynne C Stanton

    2010-02-01

    Full Text Available Cell type specification is a fundamental process that all cells must carry out to ensure appropriate behaviors in response to environmental stimuli. In fungi, cell identity is critical for defining "sexes" known as mating types and is controlled by components of mating type (MAT loci. MAT-encoded genes function to define sexes via two distinct paradigms: 1 by controlling transcription of components common to both sexes, or 2 by expressing specially encoded factors (pheromones and their receptors that differ between mating types. The human fungal pathogen Cryptococcus neoformans has two mating types (a and alpha that are specified by an extremely unusual MAT locus. The complex architecture of this locus makes it impossible to predict which paradigm governs mating type. To identify the mechanism by which the C. neoformans sexes are determined, we created strains in which the pheromone and pheromone receptor from one mating type (a replaced the pheromone and pheromone receptor of the other (alpha. We discovered that these "alpha(a" cells effectively adopt a new mating type (that of a cells; they sense and respond to alpha factor, they elicit a mating response from alpha cells, and they fuse with alpha cells. In addition, alpha(a cells lose the alpha cell type-specific response to pheromone and do not form germ tubes, instead remaining spherical like a cells. Finally, we discovered that exogenous expression of the diploid/dikaryon-specific transcription factor Sxi2a could then promote complete sexual development in crosses between alpha and alpha(a strains. These data reveal that cell identity in C. neoformans is controlled fully by three kinds of MAT-encoded proteins: pheromones, pheromone receptors, and homeodomain proteins. Our findings establish the mechanisms for maintenance of distinct cell types and subsequent developmental behaviors in this unusual human fungal pathogen.

  3. Pheromones in sex and reproduction: Do they have a role in humans?

    OpenAIRE

    2012-01-01

    Pheromones are found throughout the living world and are a primal form of communication. These chemical messengers are transported outside the body and have a direct developmental effect on hormone levels and/or behaviour. This review article aims to highlight the role of human pheromones in sex and reproduction. A review of published articles was carried out, using PubMed, medical subject heading (MSH) databases and the Scopus engine. Key words used to assess exposure, outcome, and estimates...

  4. The search for human pheromones: the lost decades and the necessity of returning to first principles

    OpenAIRE

    2015-01-01

    As humans are mammals, it is possible, perhaps even probable, that we have pheromones. However, there is no robust bioassay-led evidence for the widely published claims that four steroid molecules are human pheromones: androstenone, androstenol, androstadienone and estratetraenol. In the absence of sound reasons to test the molecules, positive results in studies need to be treated with scepticism as these are highly likely to be false positives. Common problems include small sample sizes, an ...

  5. Evolutionary deterioration of the vomeronasal pheromone transduction pathway in catarrhine primates

    OpenAIRE

    2003-01-01

    Pheromones are water-soluble chemicals released and sensed by individuals of the same species to elicit social and reproductive behaviors or physiological changes; they are perceived primarily by the vomeronasal organ (VNO) in terrestrial vertebrates. Humans and some related primates possess only vestigial VNOs and have no or significantly reduced ability to detect pheromones, a phenomenon not well understood at the molecular level. Here we show that genes encoding the...

  6. Human Pheromone Detection by the Vomeronasal Organ: Unnecessary for Mate Selection?

    OpenAIRE

    2009-01-01

    Recently, Foltan and Sedy proposed a hypothesis stating that the adult human VNO is integral to the prevention of inappropriate mate selection. In this commentary, we address the authors’ assumption that humans have a functional VNO, that pheromones are detected exclusively by the VNO, and that human pheromones are responsible for negative stimuli during mate selection. After examining the published literature on human vomeronasal function, we argue that their hypothesis is critically flawed....

  7. Ligands for pheromone-sensing neurons are not conformationally activated odorant binding proteins.

    Directory of Open Access Journals (Sweden)

    Carolina Gomez-Diaz

    Full Text Available Pheromones form an essential chemical language of intraspecific communication in many animals. How olfactory systems recognize pheromonal signals with both sensitivity and specificity is not well understood. An important in vivo paradigm for this process is the detection mechanism of the sex pheromone (Z-11-octadecenyl acetate (cis-vaccenyl acetate [cVA] in Drosophila melanogaster. cVA-evoked neuronal activation requires a secreted odorant binding protein, LUSH, the CD36-related transmembrane protein SNMP, and the odorant receptor OR67d. Crystallographic analysis has revealed that cVA-bound LUSH is conformationally distinct from apo (unliganded LUSH. Recombinantly expressed mutant versions of LUSH predicted to enhance or diminish these structural changes produce corresponding alterations in spontaneous and/or cVA-evoked activity when infused into olfactory sensilla, leading to a model in which the ligand for pheromone receptors is not free cVA, but LUSH that is "conformationally activated" upon cVA binding. Here we present evidence that contradicts this model. First, we demonstrate that the same LUSH mutants expressed transgenically affect neither basal nor pheromone-evoked activity. Second, we compare the structures of apo LUSH, cVA/LUSH, and complexes of LUSH with non-pheromonal ligands and find no conformational property of cVA/LUSH that can explain its proposed unique activated state. Finally, we show that high concentrations of cVA can induce neuronal activity in the absence of LUSH, but not SNMP or OR67d. Our findings are not consistent with the model that the cVA/LUSH complex acts as the pheromone ligand, and suggest that pheromone molecules alone directly activate neuronal receptors.

  8. Structure of Peptide Sex Pheromone Receptor PrgX and PrgX/Pheromone Complexes and Regulation of Conjugation in Enterococcus faecalis

    Energy Technology Data Exchange (ETDEWEB)

    Shi,K.; Brown, C.; Gu, Z.; Kozlowicz, B.; Dunny, G.; Ohlendorf, D.; Earhart, C.

    2005-01-01

    Many bacterial activities, including expression of virulence factors, horizontal genetic transfer, and production of antibiotics, are controlled by intercellular signaling using small molecules. To date, understanding of the molecular mechanisms of peptide-mediated cell-cell signaling has been limited by a dearth of published information about the molecular structures of the signaling components. Here, we present the molecular structure of PrgX, a DNA- and peptide-binding protein that regulates expression of the conjugative transfer genes of the Enterococcus faecalis plasmid pCF10 in response to an intercellular peptide pheromone signal. Comparison of the structures of PrgX and the PrgX/pheromone complex suggests that pheromone binding destabilizes PrgX tetramers, opening a 70-bp pCF10 DNA loop required for conjugation repression.

  9. Chemical ecology of astigmatid mites LXXXVII. S-(+)-isopiperitenone: re-identification of the alarm pheromone as the female sex pheromone in Tyrophagus similis (Acari: Acaridae).

    Science.gov (United States)

    Maruno, Gorou; Mori, Naoki; Kuwahara, Yasumasa

    2012-01-01

    Behavioral analysis revealed that S-(+)-isopiperitenone [(S)-3-methyl-6-isopropenyl-2-cyclohexen-1-one], previously identified as an alarm pheromone, is also the female sex pheromone of Tyrophagus similis (Astigmata: Acaridae), showing maximum male attraction at a dose of 0.1 female equivalent. Although the antipode, R-(-)-isopiperitenone, was not detectable in the mite extract, this synthetic optical isomer (80% e.e.) also induced activity at a dose of 100 ng, a response indicative of S-(+)-isopiperitenone being the active compound. The average content was determined to be 38.5 ng per female and 19.8 ng per male. This is the first example of an astigmatid mite species possessing a compound that functions as an alarm as well as a sex pheromone.

  10. Plant volatiles enhance behavioral responses of grapevine moth males, Lobesia botrana to sex pheromone.

    Science.gov (United States)

    von Arx, Martin; Schmidt-Büsser, Daniela; Guerin, Patrick M

    2012-02-01

    Plant volatiles play an important role in the lives of phytophagous insects, by guiding them to oviposition, feeding and mating sites. We tested the effects of different host-plant volatiles on attraction of Lobesia botrana males to the female-produced sex pheromone, in a wind tunnel. Addition of volatile emissions from grapevines or individual plant volatiles to pheromone increased the behavioral responses of L. botrana males over those to pheromone alone. At a low release rate (under-dosed) of pheromone, addition of (E)-β-caryophyllene, (Z)-3-hexenyl acetate, 1-hexanol, or 1-octen-3-ol increased all behavioral responses, from activation to pheromone source contact, while addition of (E)-4,8-dimethyl-1,3,7-nonatriene, (E)-β-farnesene, (Z)-3-hexenol, or methyl salicylate affected only the initial behavioral responses. Dose-response experiments suggested an optimal release ratio of 1:1000 (sex pheromone: host plant volatile). Our results highlight the role of plant volatiles in the sensory ecology of L. botrana.

  11. Identification of the aggregation pheromone of the melon thrips, Thrips palmi.

    Science.gov (United States)

    Akella, Sudhakar V S; Kirk, William D J; Lu, Yao-bin; Murai, Tamotsu; Walters, Keith F A; Hamilton, James G C

    2014-01-01

    The objective of this study was to identify the aggregation pheromone of the melon thrips Thrips palmi, a major pest of vegetable and ornamental plants around the world. The species causes damage both through feeding activities and as a vector of tospoviruses, and is a threat to world trade and European horticulture. Improved methods of detecting and controlling this species are needed and the identification of an aggregation pheromone will contribute to this requirement. Bioassays with a Y-tube olfactometer showed that virgin female T. palmi were attracted to the odour of live males, but not to that of live females, and that mixed-age adults of both sexes were attracted to the odour of live males, indicating the presence of a male-produced aggregation pheromone. Examination of the headspace volatiles of adult male T. palmi revealed only one compound that was not found in adult females. It was identified by comparison of its mass spectrum and chromatographic details with those of similar compounds. This compound had a structure like that of the previously identified male-produced aggregation pheromone of the western flower thrips Frankliniella occidentalis. The compound was synthesised and tested in eggplant crops infested with T. palmi in Japan. Significantly greater numbers of both males and females were attracted to traps baited with the putative aggregation pheromone compared to unbaited traps. The aggregation pheromone of T. palmi is thus identified as (R)-lavandulyl 3-methyl-3-butenoate by spectroscopic, chromatographic and behavioural analysis.

  12. Identification of the aggregation pheromone of the melon thrips, Thrips palmi.

    Directory of Open Access Journals (Sweden)

    Sudhakar V S Akella

    Full Text Available The objective of this study was to identify the aggregation pheromone of the melon thrips Thrips palmi, a major pest of vegetable and ornamental plants around the world. The species causes damage both through feeding activities and as a vector of tospoviruses, and is a threat to world trade and European horticulture. Improved methods of detecting and controlling this species are needed and the identification of an aggregation pheromone will contribute to this requirement. Bioassays with a Y-tube olfactometer showed that virgin female T. palmi were attracted to the odour of live males, but not to that of live females, and that mixed-age adults of both sexes were attracted to the odour of live males, indicating the presence of a male-produced aggregation pheromone. Examination of the headspace volatiles of adult male T. palmi revealed only one compound that was not found in adult females. It was identified by comparison of its mass spectrum and chromatographic details with those of similar compounds. This compound had a structure like that of the previously identified male-produced aggregation pheromone of the western flower thrips Frankliniella occidentalis. The compound was synthesised and tested in eggplant crops infested with T. palmi in Japan. Significantly greater numbers of both males and females were attracted to traps baited with the putative aggregation pheromone compared to unbaited traps. The aggregation pheromone of T. palmi is thus identified as (R-lavandulyl 3-methyl-3-butenoate by spectroscopic, chromatographic and behavioural analysis.

  13. Aggregation pheromone for the pepper weevil,Anthonomus eugenii cano (Coleoptera: Curculionidae): Identification and field activity.

    Science.gov (United States)

    Eller, F J; Bartelt, R J; Shasha, B S; Schuster, D J; Riley, D G; Stansly, P A; Mueller, T F; Shuler, K D; Johnson, B; Davis, J H; Sutherland, C A

    1994-07-01

    This study describes the identification of an aggregation pheromone for the pepper weevil,Anthonomus eugenii and field trials of a synthetic pheromone blend. Volatile collections and gas chromatography revealed the presence of six male-specific compounds. These compounds were identified using chromatographic and spectral techniques as: (Z)-2-(3,3-dimethylcyclohexylidene)ethanol, (E)-2-(3,3-dimethylcyclohexylidene)ethanol, (Z)-(3,3-dimethylcyclohexylidene)acetaldehyde, (E)-(3,3-dimethylcyclohexylidene)acetaldehyde, (E)-3,7-dimethyl-2,6-octadienoic acid (geranic acid), and (E)-3,7-dimethyl-2,6-octadien-1-ol (geraniol). The emission rates of these compounds from feeding males were determined to be about: 7.2, 4.8, 0.45, 0.30, 2.0, and 0.30µg/male/day, respectively. Sticky traps baited with a synthetic blend of these compounds captured more pepper weevils (both sexes) than did unbaited control traps or pheromone-baited boll weevil traps. Commercial and laboratory formulations of the synthetic pheromone were both attractive. However, the commercial formulation did not release geranic acid properly, and geranic acid is necessary for full activity. The pheromones of the pepper weevil and the boll weevil are compared. Improvements for increasing trap efficiency and possible uses for the pepper weevil pheromone are discussed. A convenient method for purifying geranic acid is also described.

  14. Synthesis and biological activity of conformationally restricted gypsy moth pheromone mimics.

    Science.gov (United States)

    Chen, Hao; Gong, Yongmei; Gries, Regine M; Plettner, Erika

    2010-04-15

    The design and synthesis of a series of conformationally constrained mimics of gypsy moth sex pheromone, (+)-disparlure (7R,8S)-2-methyl-7,8-epoxyoctadecane, are described. The core structure of the mimics is derived from 5-(2'-hydroxyethyl)cyclopent-2-en-1-ol. Substituent optimization of the analogs was accomplished through the synthesis of mini-libraries and pure individual compounds, followed by electrophysiological experiments with male gypsy moth antennae. The electroantennogram results show that the analogs elicited weak to no antennal responses themselves. There was a clear structure-activity pattern for odorant activity, with ethyl substituents being best. Further, when puffed simultaneously with the pheromone, some of the compounds gave a significant enhancement of the antennal depolarization, indicating an additive or synergistic effect. A pure pheromone stimulus following a mixed compound/pheromone stimulus was generally not affected, with two exceptions: one compound enhanced and another inhibited a subsequent stimulus. The compounds also prolonged the stimulation of the antenna, which manifested itself in widened electroantennogram peaks. We tested the hypothesis that this prolonged stimulation may be due to the stabilization of a particular conformer of the pheromone-binding protein (PBP). Compounds that caused PBP2 to adopt a similar conformation than in the presence of pheromone also caused peak widening. This was not the case with PBP1.

  15. Genome-wide identification of pheromone-targeted transcrption in fission yeast

    DEFF Research Database (Denmark)

    Xue-Franzen, Y.; Kjærulff, S.; Holmberg, C.;

    2006-01-01

    Background Fission yeast cells undergo sexual differentiation in response to nitrogen starvation. In this process haploid M and P cells first mate to form diploid zygotes, which then enter meiosis and sporulate. Prior to mating, M and P cells communicate with diffusible mating pheromones that act......Background Fission yeast cells undergo sexual differentiation in response to nitrogen starvation. In this process haploid M and P cells first mate to form diploid zygotes, which then enter meiosis and sporulate. Prior to mating, M and P cells communicate with diffusible mating pheromones...... that activate a signal transduction pathway in the opposite cell type. The pheromone signalling orchestrates mating and is also required for entry into meiosis. Results Here we use DNA microarrays to identify genes that are induced by M-factor in P cells and by P-factor in M-cells. The use of a cyr1 genetic...... background allowed us to study pheromone signalling independently of nitrogen starvation. We identified a total of 163 genes that were consistently induced more than two-fold by pheromone stimulation. Gene disruption experiments demonstrated the involvement of newly discovered pheromone-induced genes...

  16. Aggressive reproductive competition among hopelessly queenless honeybee workers triggered by pheromone signaling

    Science.gov (United States)

    Malka, O.; Shnieor, S.; Katzav-Gozansky, T.; Hefetz, A.

    2008-06-01

    In the honeybee, Apis mellifera, the queen monopolizes reproduction, while the sterile workers cooperate harmoniously in nest maintenance. However, under queenless (QL) conditions, cooperation collapses and reproductive competition among workers ensues. This is mediated through aggression and worker oviposition, as well as shifts in pheromones, from worker to queen-like composition. Many studies suggest a dichotomy between conflict resolution through aggression or through pheromonal signaling. In this paper, we demonstrate that both phenomena comprise essential components of reproductive competition and that pheromone signaling actually triggers the onset of aggression. We kept workers as QL groups until first aggression was observed and subsequently determined the contestants’ reproductive status and content of the mandibular (MG) and Dufour’s glands (DG). In groups in which aggression occurred early, the attacked bee had consistently more queen-like pheromone in both the MG and DG, although both contestants had undeveloped ovaries. In groups with late aggression, the attacked bee had consistently larger oocytes and more queen-like pheromone in the DG, but not the MG. We suggest that at early stages of competition, the MG secretion is utilized to establish dominance and that the DG provides an honest fertility signal. We further argue that it is the higher amount of DG pheromone that triggers aggression.

  17. Neural correlates underlying naloxone-induced amelioration of sexual behavior deterioration due to an alarm pheromone

    Directory of Open Access Journals (Sweden)

    Tatsuya eKobayashi

    2015-02-01

    Full Text Available Sexual behavior is suppressed by various types of stressors. We previously demonstrated that an alarm pheromone released by stressed male Wistar rats is a stressor to other rats, increases the number of mounts needed for ejaculation, and decreases the hit rate (described as the number of intromissions/sum of the mounts and intromissions. This deterioration in sexual behavior was ameliorated by pretreatment with the opioid receptor antagonist naloxone. However, the neural mechanism underlying this remains to be elucidated. Here, we examined Fos expression in 31 brain regions of pheromone-exposed rats and naloxone-pretreated pheromone-exposed rats 60 min after 10 intromissions. As previously reported, the alarm pheromone increased the number of mounts and decreased the hit rate. In addition, Fos expression was increases in the anterior medial division, anterior lateral division and posterior division of the bed nucleus of the stria terminalis, parvocellular part of the paraventricular nucleus of the hypothalamus, arcuate nucleus, dorsolateral and ventrolateral periaqueductal gray, and nucleus paragigantocellularis. Fos expression decreased in the magnocellular part of the paraventricular nucleus of the hypothalamus. Pretreatment with naloxone blocked the pheromone-induced changes in Fos expression in the magnocellular part of the paraventricular nucleus of the hypothalamus, ventrolateral periaqueductal gray, and nucleus paragigantocellularis. Based on these results, we hypothesize that the alarm pheromone deteriorated sexual behavior by activating the ventrolateral periaqueductal gray-nucleus paragigantocellularis cluster and suppressing the magnocellular part of the paraventricular nucleus of the hypothalamus via the opioidergic pathway.

  18. A host beetle pheromone regulates development and behavior in the nematode Pristionchus pacificus.

    Science.gov (United States)

    Cinkornpumin, Jessica K; Wisidagama, Dona R; Rapoport, Veronika; Go, James L; Dieterich, Christoph; Wang, Xiaoyue; Sommer, Ralf J; Hong, Ray L

    2014-10-15

    Nematodes and insects are the two most speciose animal phyla and nematode-insect associations encompass widespread biological interactions. To dissect the chemical signals and the genes mediating this association, we investigated the effect of an oriental beetle sex pheromone on the development and behavior of the nematode Pristionchus pacificus. We found that while the beetle pheromone is attractive to P. pacificus adults, the pheromone arrests embryo development, paralyzes J2 larva, and inhibits exit of dauer larvae. To uncover the mechanism that regulates insect pheromone sensitivity, a newly identified mutant, Ppa-obi-1, is used to reveal the molecular links between altered attraction towards the beetle pheromone, as well as hypersensitivity to its paralyzing effects. Ppa-obi-1 encodes lipid-binding domains and reaches its highest expression in various cell types, including the amphid neuron sheath and excretory cells. Our data suggest that the beetle host pheromone may be a species-specific volatile synomone that co-evolved with necromeny.

  19. Evolutionary deterioration of the vomeronasal pheromone transduction pathway in catarrhine primates.

    Science.gov (United States)

    Zhang, Jianzhi; Webb, David M

    2003-07-08

    Pheromones are water-soluble chemicals released and sensed by individuals of the same species to elicit social and reproductive behaviors or physiological changes; they are perceived primarily by the vomeronasal organ (VNO) in terrestrial vertebrates. Humans and some related primates possess only vestigial VNOs and have no or significantly reduced ability to detect pheromones, a phenomenon not well understood at the molecular level. Here we show that genes encoding the TRP2 ion channel and V1R pheromone receptors, two components of the vomeronasal pheromone signal transduction pathway, have been impaired and removed from functional constraints since shortly before the separation of hominoids and Old World monkeys approximately 23 million years ago, and that the random inactivation of pheromone receptor genes is an ongoing process even in present-day humans. The phylogenetic distribution of vomeronasal pheromone insensitivity is concordant with those of conspicuous female sexual swelling and male trichromatic color vision, suggesting that a vision-based signaling-sensory mechanism may have in part replaced the VNO-mediated chemical-based system in the social/reproductive activities of hominoids and Old World monkeys (catarrhines).

  20. Defining pheromone-receptor signaling in Candida albicans and related asexual Candida species.

    Science.gov (United States)

    Lin, Ching-Hsuan; Choi, Anthony; Bennett, Richard J

    2011-12-01

    Candida albicans is an important human fungal pathogen in which sexual reproduction is under the control of the novel white-opaque switch. Opaque cells are the mating-competent form, whereas white cells do not mate but can still respond to pheromones, resulting in biofilm formation. In this study, we first define the domains of the α-pheromone receptor Ste2 that are necessary for signaling in both white and opaque forms. Both cell states require the IC loop 3 (IC3) and the C-terminal tail of Ste2 for the cellular response, whereas the first IC loop (IC1) of Ste2 is dispensable for signaling. To also address pheromone-receptor interactions in related species, including apparently asexual Candida species, Ste2 orthologues were heterologously expressed in Candida albicans. Ste2 receptors from multiple Candida clade species were functional when expressed in C. albicans, whereas the Ste2 receptor of Candida lusitaniae was nonfunctional. Significantly, however, expression of a chimeric C. lusitaniae Ste2 receptor containing the C-terminal tail of Ste2 from C. albicans generated a productive response to C. lusitaniae pheromone. This system has allowed us to characterize pheromones from multiple Candida species and indicates that functional pheromone-receptor couples exist in fungal species that have yet to be shown to undergo sexual mating.

  1. The search for human pheromones: the lost decades and the necessity of returning to first principles.

    Science.gov (United States)

    Wyatt, Tristram D

    2015-04-07

    As humans are mammals, it is possible, perhaps even probable, that we have pheromones. However, there is no robust bioassay-led evidence for the widely published claims that four steroid molecules are human pheromones: androstenone, androstenol, androstadienone and estratetraenol. In the absence of sound reasons to test the molecules, positive results in studies need to be treated with scepticism as these are highly likely to be false positives. Common problems include small sample sizes, an overestimate of effect size (as no effect can be expected), positive publication bias and lack of replication. Instead, if we are to find human pheromones, we need to treat ourselves as if we were a newly discovered mammal, and use the rigorous methods already proven successful in pheromone research on other species. Establishing a pheromone relies on demonstration of an odour-mediated behavioural or physiological response, identification and synthesis of the bioactive molecule(s), followed by bioassay confirmation of activity. Likely sources include our sebaceous glands. Comparison of secretions from adult and pre-pubertal humans may highlight potential molecules involved in sexual behaviour. One of the most promising human pheromone leads is a nipple secretion from the areola glands produced by all lactating mothers, which stimulates suckling by any baby not just their own.

  2. Inhibition of the responses to sex pheromone of the fall armyworm, Spodoptera frugiperda.

    Science.gov (United States)

    Malo, Edi A; Rojas, Julio C; Gago, Rafael; Guerrero, Ángel

    2013-01-01

    Trifluoromethyl ketones reversibly inhibit pheromone-degrading esterases in insect olfactory tissues, affecting pheromone detection and behavior of moth males. In this work, (Z)-9-tetradecenyl trifluoromethyl ketone (Z9-14:TFMK), a closely-related analogue of the pheromone of the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), was prepared and tested in electroantennogram and field tests as possible inhibitors of the pheromone action. The electroantennogram parameters, amplitude, and the repolarization time of the antennal responses of S. frugiperda males were affected by Z9-14:TFMK vapors. Exposure of male antennae to a stream of air passing through 100 μg of the ketone produced a significant reduction of the amplitude and an increase of 2/3 repolarization time signals to the pheromone. The effect was reversible and dose-dependent. In the field, the analogue significantly decreased the number of males caught when mixed with the pheromone in 10:1 ratio. The results suggest that Z9-14:TFMK is a mating disruptant of S. frugiperda and may be a good candidate to consider in future strategies to control this pest.

  3. The Effect of Trail Pheromone and Path Confinement on Learning of Complex Routes in the Ant Lasius niger

    Science.gov (United States)

    Czaczkes, Tomer J.; Weichselgartner, Tobias; Bernadou, Abel; Heinze, Jürgen

    2016-01-01

    Route learning is key to the survival of many central place foragers, such as bees and many ants. For ants which lay pheromone trails, the presence of a trail may act as an important source of information about whether an error has been made. The presence of trail pheromone has been demonstrated to support route learning, and the effect of pheromones on route choice have been reported to persist even after the pheromones have been removed. This could be explained in two ways: the pheromone may constrain the ants onto the correct route, thus preventing errors and aiding learning. Alternatively, the pheromones may act as a ‘reassurance’, signalling that the learner is on the right path and that learning the path is worthwhile. Here, we disentangle pheromone presence from route confinement in order to test these hypotheses, using the ant Lasius niger as a model. Unexpectedly, we did not find any evidence that pheromones support route learning. Indeed, there was no evidence that ants confined to the correct route learned at all. Thus, while we cannot support the ‘reassurance’ hypothesis, we can rule out the ‘confinement’ hypothesis. Other findings, such as a reduction in pheromone deposition in the presence of trail pheromones, are remarkably consistent with previous experiments. As previously reported, ants which make errors on their outward journey upregulate pheromone deposition on their return. Surprisingly, ants which would go on to make an error down-regulate pheromone deposition on their outward journey, hinting at a capacity for ants to gauge the quality of their own memories. PMID:26959996

  4. Species Specificity of the Putative Male Antennal Aphrodisiac Pheromone in Leptopilina heterotoma, Leptopilina boulardi, and Leptopilina victoriae

    OpenAIRE

    Ingmar Weiss; Joachim Ruther; Johannes Stökl

    2015-01-01

    Male antennal aphrodisiac pheromones have been suggested to elicit female receptiveness in several parasitic Hymenoptera, including Leptopilina boulardi. None of the proposed pheromones, however, has been fully identified to date. It is also unknown whether these antennal pheromones are species specific, because the species specificity of mate recognition and courtship elicitation in Leptopilina prevented such experiments. In this study we present an experimental design that allows the invest...

  5. The Effect of Trail Pheromone and Path Confinement on Learning of Complex Routes in the Ant Lasius niger.

    Directory of Open Access Journals (Sweden)

    Tomer J Czaczkes

    Full Text Available Route learning is key to the survival of many central place foragers, such as bees and many ants. For ants which lay pheromone trails, the presence of a trail may act as an important source of information about whether an error has been made. The presence of trail pheromone has been demonstrated to support route learning, and the effect of pheromones on route choice have been reported to persist even after the pheromones have been removed. This could be explained in two ways: the pheromone may constrain the ants onto the correct route, thus preventing errors and aiding learning. Alternatively, the pheromones may act as a 'reassurance', signalling that the learner is on the right path and that learning the path is worthwhile. Here, we disentangle pheromone presence from route confinement in order to test these hypotheses, using the ant Lasius niger as a model. Unexpectedly, we did not find any evidence that pheromones support route learning. Indeed, there was no evidence that ants confined to the correct route learned at all. Thus, while we cannot support the 'reassurance' hypothesis, we can rule out the 'confinement' hypothesis. Other findings, such as a reduction in pheromone deposition in the presence of trail pheromones, are remarkably consistent with previous experiments. As previously reported, ants which make errors on their outward journey upregulate pheromone deposition on their return. Surprisingly, ants which would go on to make an error down-regulate pheromone deposition on their outward journey, hinting at a capacity for ants to gauge the quality of their own memories.

  6. The Effect of Trail Pheromone and Path Confinement on Learning of Complex Routes in the Ant Lasius niger.

    Science.gov (United States)

    Czaczkes, Tomer J; Weichselgartner, Tobias; Bernadou, Abel; Heinze, Jürgen

    2016-01-01

    Route learning is key to the survival of many central place foragers, such as bees and many ants. For ants which lay pheromone trails, the presence of a trail may act as an important source of information about whether an error has been made. The presence of trail pheromone has been demonstrated to support route learning, and the effect of pheromones on route choice have been reported to persist even after the pheromones have been removed. This could be explained in two ways: the pheromone may constrain the ants onto the correct route, thus preventing errors and aiding learning. Alternatively, the pheromones may act as a 'reassurance', signalling that the learner is on the right path and that learning the path is worthwhile. Here, we disentangle pheromone presence from route confinement in order to test these hypotheses, using the ant Lasius niger as a model. Unexpectedly, we did not find any evidence that pheromones support route learning. Indeed, there was no evidence that ants confined to the correct route learned at all. Thus, while we cannot support the 'reassurance' hypothesis, we can rule out the 'confinement' hypothesis. Other findings, such as a reduction in pheromone deposition in the presence of trail pheromones, are remarkably consistent with previous experiments. As previously reported, ants which make errors on their outward journey upregulate pheromone deposition on their return. Surprisingly, ants which would go on to make an error down-regulate pheromone deposition on their outward journey, hinting at a capacity for ants to gauge the quality of their own memories.

  7. A stochastic model of ant trail following with two pheromones

    CERN Document Server

    Malíčková, Miriam; Boďová, Katarína

    2015-01-01

    Colonies of ants are systems of interacting living organisms in which interactions between individuals and their environment can produce a reliable performance of a complex tasks without the need for centralised control. Particularly remarkable is the process of formation of refined paths between the nest and food sources that is essential for successful foraging. We have designed a simple stochastic off-lattice model of ant foraging in the absence of direct communication. The motion of ants is governed by two components - a random change in direction of motion that improves ability to explore the environment (facilitating food discovery), and a non-random global indirect interaction component based on pheromone signalling. Using numerical simulations we have studied the model behaviour in different parameter regimes and tested the ability of our model ants to adapt to changes in the external environment. The simulated behaviour of ants in the model recapitulated the experimentally observed behaviours of real...

  8. Pheromone-Based Ant Routing System for IP Networks

    Institute of Scientific and Technical Information of China (English)

    张林; 任勇; 山秀明

    2004-01-01

    The pheromone-based ant routing algorithm is a distributed routing algorithm with good scalability and robustness. A 2-D cellular automata (CA) model of the computer network was presented to analyze the algorithm. The results show that the procedure of establishing a stable route is self-organized towards the attractive peculiar state, and the duration of time for the routing establishment is power-law distributed. A practical ant routing protocol over an IP network was also presented, and two simulations were done to compare the performance dynamic and the load balancing performance between this protocol and the open shortest path first (OSPF) protocol. The results show that the ant routing protocol out-performs OSPF in these aspects.

  9. Swelling of Erectile Nasal Tissue Induced by Human Sexual Pheromone.

    Science.gov (United States)

    Mazzatenta, Andrea; De Luca, C; Di Tano, A; Cacchio, M; Di Giulio, C; Pokorski, Mieczyslaw

    2016-01-01

    Most chemically mediated sexual communication in humans remains uncharacterized. Yet the study of sexual communication is decisive for understanding sexual behavior and evolutive mechanisms in our species. Here we provide the evidence to consider 4,16-androstadien-3-one (AND) as a man's sexual pheromone. Our experiment provides support for the physiological effect of AND on nasal airway resistance (Rna) in women, as assessed by anterior rhinomanometry. We found that AND administration increased the area of turbinate during the ovulatory phase, resulting in an increase of Rna. Thus, we discovered that minute amounts of AND, acting through neuroendocrine brain control, regulate Rna and consequently affect the sexual physiology and behavior. Fascinatingly, this finding provides the evidence of the preservation of chemosexual communication in humans, which it has been largely neglected due to its unconscious perception and concealed nature. Therefore, chemical communication is a plesiomorphic evolutive phenomenon in humans.

  10. Novel sex cells and evidence for sex pheromones in diatoms.

    Directory of Open Access Journals (Sweden)

    Shinya Sato

    Full Text Available BACKGROUND: Diatoms belong to the stramenopiles, one of the largest groups of eukaryotes, which are primarily characterized by a presence of an anterior flagellum with tubular mastigonemes and usually a second, smooth flagellum. Based on cell wall morphology, diatoms have historically been divided into centrics and pennates, of which only the former have flagella and only on the sperm. Molecular phylogenies show the pennates to have evolved from among the centrics. However, the timing of flagellum loss--whether before the evolution of the pennate lineage or after--is unknown, because sexual reproduction has been so little studied in the 'araphid' basal pennate lineages, to which Pseudostaurosira belongs. METHODS/PRINCIPAL FINDING: Sexual reproduction of an araphid pennate, Pseudostaurosira trainorii, was studied with light microscopy (including time lapse observations and immunofluorescence staining observed under confocal scanning laser microscopy and SEM. We show that the species produces motile male gametes. Motility is mostly associated with the extrusion and retrieval of microtubule-based 'threads', which are structures hitherto unknown in stramenopiles, their number varying from one to three per cell. We also report experimental evidence for sex pheromones that reciprocally stimulate sexualization of compatible clones and orientate motility of the male gametes after an initial 'random walk'. CONCLUSIONS/SIGNIFICANCE: The threads superficially resemble flagella, in that both are produced by male gametes and contain microtubules. However, one striking difference is that threads cannot beat or undulate and have no motility of their own, and they do not bear mastigonemes. Threads are sticky and catch and draw objects, including eggs. The motility conferred by the threads is probably crucial for sexual reproduction of P. trainorii, because this diatom is non-motile in its vegetative stage but obligately outbreeding. Our pheromone experiments

  11. The Aggregation Pheromone of Phyllotreta striolata (Coleoptera: Chrysomelidae) Revisited.

    Science.gov (United States)

    Beran, Franziska; Jiménez-Alemán, Guillermo H; Lin, Mei-Ying; Hsu, Yun-Che; Mewis, Inga; Srinivasan, Ramasamy; Ulrichs, Christian; Boland, Wilhelm; Hansson, Bill S; Reinecke, Andreas

    2016-08-01

    Aggregations of the striped flea beetle Phyllotreta striolata on their crucifer host plants are mediated by volatiles emitted from feeding males. The male-specific sesquiterpene, (6R,7S)-himachala-9,11-diene (compound A), was shown previously to be physiologically and behaviorally active, but compound A was attractive only when combined with unnaturally high doses of the host plant volatile allyl isothiocyanate (AITC) in field trapping experiments. This indicated that our understanding of the chemical communication in this species is incomplete. Another male-specific sesquiterpenoid, (3S,9R,9aS)-3-hydroxy-3,5,5,9-tetramethyl-5,6,7,8,9,9a-hexahydro-1H-benzo[7]annulen-2(3H)-one (compound G), has been reported from an American P. striolata population. We confirmed the presence of compound G, and investigated its interaction with compound A and AITC in a P. striolata population in Taiwan. Compound G was attractive to Taiwanese P. striolata in laboratory bioassays, but significantly more beetles were attracted to a blend of compounds A and G. Under the same conditions, P. striolata showed no preference for the blend of A and G combined with a range of doses of AITC over the sesquiterpenoid blend alone. The sesquiterpenoid blend was tested further in field trapping experiments and attracted significantly more beetles than traps baited with compound A and ecologically relevant amounts of AITC. We conclude that A and G are components of the male-specific aggregation pheromone of P. striolata in Taiwan, and that the attractiveness of the pheromone is not reliant on the presence of AITC. Our results further indicate that the male-specific sesquiterpenoid blends differ qualitatively between the Taiwanese and American populations of P. striolata.

  12. Genes involved in sex pheromone biosynthesis of Ephestia cautella, an important food storage pest, are determined by transcriptome sequencing

    KAUST Repository

    Antony, Binu

    2015-07-18

    Background Insects use pheromones, chemical signals that underlie all animal behaviors, for communication and for attracting mates. Synthetic pheromones are widely used in pest control strategies because they are environmentally safe. The production of insect pheromones in transgenic plants, which could be more economical and effective in producing isomerically pure compounds, has recently been successfully demonstrated. This research requires information regarding the pheromone biosynthetic pathways and the characterization of pheromone biosynthetic enzymes (PBEs). We used Illumina sequencing to characterize the pheromone gland (PG) transcriptome of the Pyralid moth, Ephestia cautella, a destructive storage pest, to reveal putative candidate genes involved in pheromone biosynthesis, release, transport and degradation. Results We isolated the E. cautella pheromone compound as (Z,E)-9,12-tetradecadienyl acetate, and the major pheromone precursors 16:acyl, 14:acyl, E14-16:acyl, E12-14:acyl and Z9,E12-14:acyl. Based on the abundance of precursors, two possible pheromone biosynthetic pathways are proposed. Both pathways initiate from C16:acyl-CoA, with one involving ∆14 and ∆9 desaturation to generate Z9,E12-14:acyl, and the other involving the chain shortening of C16:acyl-CoA to C14:acyl-CoA, followed by ∆12 and ∆9 desaturation to generate Z9,E12-14:acyl-CoA. Then, a final reduction and acetylation generates Z9,E12-14:OAc. Illumina sequencing yielded 83,792 transcripts, and we obtained a PG transcriptome of ~49.5 Mb. A total of 191 PBE transcripts, which included pheromone biosynthesis activating neuropeptides, fatty acid transport proteins, acetyl-CoA carboxylases, fatty acid synthases, desaturases, β-oxidation enzymes, fatty acyl-CoA reductases (FARs) and fatty acetyltransferases (FATs), were selected from the dataset. A comparison of the E. cautella transcriptome data with three other Lepidoptera PG datasets revealed that 45 % of the sequences were shared

  13. 10-Methyldodecanal, a Novel Attractant Pheromone Produced by Males of the South American Cerambycid Beetle Eburodacrys vittata.

    Science.gov (United States)

    Silva, Weliton D; Millar, Jocelyn G; Hanks, Lawrence M; Bento, José Maurício S

    2016-01-01

    We report the identification, synthesis, and field bioassay of a novel attractant pheromone produced by males of Eburodacrys vittata (Blanchard), a South American cerambycid beetle in the subfamily Cerambycinae. Headspace volatiles from males contained a sex-specific compound, identified as 10-methyldodecanal. In a field bioassay conducted in Brazil, significant numbers of males and females were caught in traps baited with synthesized racemic 10-methyldodecanal, consistent with the aggregation-sex pheromones produced by males of many cerambycine species. This compound represents a new structural class of cerambycid pheromones, and it is the first pheromone identified for a species in the tribe Eburiini.

  14. Identification and characterization of a fatty acyl reductase from a Spodoptera littoralis female gland involved in pheromone biosynthesis.

    Science.gov (United States)

    Carot-Sans, G; Muñoz, L; Piulachs, M D; Guerrero, A; Rosell, G

    2015-02-01

    Fatty acyl-CoA reductases (FARs), the enzymes that catalyse reduction of a fatty acyl-CoA to the corresponding alcohol in insect pheromone biosynthesis, are postulated to play an important role in determining the proportion of each component in the pheromone blend. For the first time, we have isolated and characterized from the Egyptian cotton leaf worm Spodoptera littoralis (Lepidoptera: Noctuidae) a FAR cDNA (Slit-FAR1), which appeared to be expressed only in the pheromone gland and was undetectable in other female tissues, such as fat body, ovaries, wings, legs or thorax. The encoded protein has been successfully expressed in a recombinant system, and the recombinant enzyme is able to produce the intermediate fatty acid alcohols of the pheromone biosynthesis of S. littoralis from the corresponding acyl-CoA precursors. The kinetic variables Km and Vmax, which have been calculated for each acyl-CoA pheromone precursor, suggest that in S. littoralis pheromone biosynthesis other biosynthetic enzymes (e.g. desaturases, acetyl transferase) should also contribute to the final ratio of components of the pheromone blend. In a phylogenetic analysis, Slit-FAR1 appeared grouped in a cluster of other FARs involved in the pheromone biosynthesis of other insects, with little or non-specificity for the natural pheromone precursors.

  15. Sex pheromones of Callosobruchus subinnotatus and C. maculatus (Coleoptera: Bruchidae): congeneric responses and role of air movement.

    Science.gov (United States)

    Mbata, G N; Shu, S; Ramaswamy, S B

    2000-04-01

    Females of Callosobruchus spp. are known to produce sex pheromones that attract males. These sex pheromones cannot be adopted for use in pest management without first investigating the responses of the males in the windless conditions of storage environments. Consequently, behavioural bioassays of Callosobruchus subinnotatus Pic males were conducted in an olfactometer in the absence of air-flow. Under these conditions males were found to be able to follow odour trails to the source. However, the latency period was longer in diffusional bioassays than for insects in a Y-tube olfactometer that provided directional wind cues. The highest percentage of males reached the pheromone source when components of the pheromones, (E)-3-methyl-2-heptenoic acid (E32A) and (Z)-3-methyl-2-heptenoic acid (Z32A), were formulated in a 50:50 or 25:75 ratio. Males of C. maculatus (Fabricius) responded to sex pheromone of C. subinnotatus, but males of C. subinnotatus did not respond to that of C. maculatus. The two sex pheromone components of C. subinnotatus are also constituents of C. maculatus sex pheromone. These two components may be potentially useful in monitoring the populations of both species in stored beans. It is postulated that (Z)-3-methyl-3-heptenoic acid (Z33A), the major component of the sex pheromone of C. maculatus, must have acted as an antagonist inhibiting response of C. subinnotatus to the sex pheromone of C. maculatus.

  16. Tucannon River Spring Chinook Salmon Captive Brood Program, FY 2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Bumgarner, Joseph D.; Gallinat, Michael P.

    2001-06-01

    This report summarizes the objectives, tasks, and accomplishments of the Tucannon River spring chinook captive brood program from program inception (1997) through April 2001. The WDFW initiated a captive broodstock program in 1997. The overall goal of the Tucannon River captive broodstock program is for the short-term, and eventually long-term, rebuilding of the Tucannon River spring chinook salmon run, with the hope that natural production will eventually sustain itself. The project goal is to rear captive salmon to adults, spawn them, rear their progeny, and release approximately 150,000 smolts annually into the Tucannon River between 2003-2007. These smolt releases, in combination with the current hatchery supplementation program (132,000 smolts), and wild production, is expected to produce 600-700 returning adult spring chinook to the Tucannon River each year from 2005-2010. The Master Plan, Environmental Assessment, and most facility modifications at LFH were completed for the Tucannon River spring chinook captive broodstock program during FY2000 and FY2001. DNA samples collected since 1997 have been sent to the WDFW genetics lab in Olympia for baseline DNA analysis. Results from the genetic analysis are not available at this time. The captive broodstock program is planned to collect fish from five (1997-2001) brood years (BY). The captive broodstock program was initiated with 1997 BY juveniles, and the 2000 BY fish have been selected. As of April 30, 2001, WDFW has 172 BY 1997, 262 BY 1998, 407 BY 1999, and approximately 1,190 BY 2000 fish on hand at LFH. Twelve of 13 mature 97 BY females were spawned in 2000. Total eggtake was 14,813. Mean fecundity was 1,298 eggs/female based on 11 fully spawned females. Egg survival to eye-up was 47.3%. This low survival was expected for three year old captive broodstock females. As of April 30, 2001, WDFW has 4,211 captive broodstock progeny on hand. These fish will be tagged with blank wire tag without fin clips and

  17. Alternative reproductive tactics in snail shell-brooding cichlids diverge in energy reserve allocation.

    Science.gov (United States)

    von Kuerthy, Corinna; Tschirren, Linda; Taborsky, Michael

    2015-05-01

    Life history theory predicts that the amount of resources allocated to reproduction should maximize an individual's lifetime reproductive success. So far, resource allocation in reproduction has been studied mainly in females. Intraspecific variation of endogenous energy storage and utilization patterns of males has received little attention, although these patterns may vary greatly between individuals pursuing alternative reproductive tactics (ARTs). ARTs are characterized by systematic variation of behavioral, physiological, and often morphological traits among same-sex conspecifics. Some individuals may rely on previously accumulated reserves, because of limited foraging opportunities during reproduction. Others may be able to continue foraging during reproduction, thus relying on reserves to a lesser extent. We therefore predicted that, if male tactics involve such divergent limitations and trade-offs within a species, ARTs should correspondingly differ in energy reserve allocation and utilization. To test this prediction, we studied short-term and long-term reserve storage patterns of males in the shell-brooding cichlid Lamprologus callipterus. In this species, bourgeois males investing in territory defense, courtship, and guarding of broods coexist with two distinct parasitic male tactics: (1) opportunistic sneaker males attempting to fertilize eggs by releasing sperm into the shell opening when a female is spawning; and (2) specialized dwarf males attempting to enter the shell past the spawning female to fertilize eggs from inside the shell. Sneaker males differed from other male types by showing the highest amount of accumulated short-term and long-term fat stores, apparently anticipating their upcoming adoption of the nest male status. In contrast, nest males depleted previously accumulated energy reserves with increasing nest holding period, as they invest heavily into costly reproductive behaviors while not taking up any food. This conforms to a capital

  18. The activity of carbohydrate-degrading enzymes in the development of brood and newly emerged workers and drones of the Carniolan honeybee, Apis mellifera carnica.

    Science.gov (United States)

    Żółtowska, Krystyna; Lipiński, Zbigniew; Łopieńska-Biernat, Elżbieta; Farjan, Marek; Dmitryjuk, Małgorzata

    2012-01-01

    The activity of glycogen Phosphorylase and carbohydrate hydrolyzing enzymes α-amylase, glucoamylase, trehalase, and sucrase was studied in the development of the Carniolan honey bee, Apis mellifera carnica Pollman (Hymenoptera: Apidae), from newly hatched larva to freshly emerged imago of worker and drone. Phosphorolytic degradation of glycogen was significantly stronger than hydrolytic degradation in all developmental stages. Developmental profiles of hydrolase activity were similar in both sexes of brood; high activity was found in unsealed larvae, the lowest in prepupae followed by an increase in enzymatic activity. Especially intensive increases in activity occurred in the last stage of pupae and newly emerged imago. Besides α-amylase, the activities of other enzymes were higher in drone than in worker broods. Among drones, activity of glucoamylase was particularly high, ranging from around three times higher in the youngest larvae to 13 times higher in the oldest pupae. This confirms earlier suggestions about higher rates of metabolism in drone broods than in worker broods.

  19. Honey bees (Apis mellifera) reared in brood combs containing high levels of pesticide residues exhibit increased susceptibility to Nosema (Microsporidia) infection.

    Science.gov (United States)

    Wu, Judy Y; Smart, Matthew D; Anelli, Carol M; Sheppard, Walter S

    2012-03-01

    Nosema ceranae and pesticide exposure can contribute to honey bee health decline. Bees reared from brood comb containing high or low levels of pesticide residues were placed in two common colony environments. One colony was inoculated weekly with N. ceranae spores in sugar syrup and the other colony received sugar syrup only. Worker honey bees were sampled weekly from the treatment and control colonies and analyzed for Nosema spore levels. Regardless of the colony environment (spores+syrup added or syrup only added), a higher proportion of bees reared from the high pesticide residue brood comb became infected with N. ceranae, and at a younger age, compared to those reared in low residue brood combs. These data suggest that developmental exposure to pesticides in brood comb increases the susceptibility of bees to N. ceranae infection.

  20. Synthesis and assessment of attractiveness and mating disruption efficacy of sex pheromone microcapsules for the diamondback moth,Plutella xylostella (L.)

    Institute of Scientific and Technical Information of China (English)

    CHEN ZengLiang; FANG YuLing; ZHANG ZhongNing

    2007-01-01

    Microcapsules of sex pheromone of the diamondback moth (DBM),Plutella xylostella (Lepidoptera:Plutellidae) were synthesized through complex coacervation using gelatin and gum arabic as wall-forming materials.The encapsulated pheromone released from these microcapsules into the air was monitored over six weeks in the field.Results of a field trial show that the attractiveness of microcapsules was superior to that of rubber septa loaded with the same amount of pheromone.The mating disruption efficiency of the pheromone treatment was estimated through comparing numbers of moths captured in pheromone-baited traps placed in pheromone treatment fields and pesticide treatment fields.The estimated mating disruption efficiency of the pheromone treatments ranged from 76.94% to 98.67% during the season.This study shows that pheromone microcapsules might provide a new method for P.xylostella control.

  1. Brood size manipulations in a spatially and temporally varying environment: male Tengmalm's owls pass increased reproductive costs to offspring.

    Science.gov (United States)

    Thomson, Robert L; Griesser, Michael; Laaksonen, Toni; Korpimäki, Erkki

    2014-10-01

    A key tool used to assess reproductive trade-offs in birds is brood size manipulation (BSM) experiments. Most BSM studies have examined the influence on short-term measures of reproductive output. Seldom evaluated are the effects on long-term fitness proxies under temporally or spatially varying environments. Unpredictable environments may affect reproductive trade-offs by altering the value of the brood or hampering optimization of reproductive effort. We reduced or enlarged broods of 140 male Tengmalm's owls Aegolius funereus by one chick during their first lifetime reproductive event. Males differed in age and bred in environments that varied in quality spatially (habitat structure) and temporally (abundance of main food). We measured the short-term (nestling number and condition) and long-term fitness proxies (survival, lifetime fledgling and recruits produced) until all experimental males disappeared from the population. BSMs did not affect fledgling number or condition, but in enlarged broods, offspring condition was lower in territories with a high proportion of agricultural fields. Importantly, no obvious impacts on long-term fitness proxies emerged; lifetime fledgling and recruit production of males did not differ between the BSM treatments. Thus, the primary caregiver (i.e. Tengmalm's owl males) passed increased reproductive costs to their offspring, which is in agreement with other studies investigating intergenerational reproductive trade-offs in species of intermediate lifespan. Reluctance to accept increased current reproductive costs in these systems highlights the potential for sexual conflict in bi-parental care systems in which one of the pair is the primary caregiver.

  2. Egg color variation, but not egg rejection behavior, changes in a cuckoo host breeding in the absence of brood parasitism.

    Science.gov (United States)

    Yang, Canchao; Liu, Yang; Zeng, Lijin; Liang, Wei

    2014-06-01

    Interactions between parasitic cuckoos and their songbird hosts form a classical reciprocal "arms race," and are an excellent model for understanding the process of coevolution. Changes in host egg coloration via the evolution of interclutch variation in egg color or intraclutch consistency in egg color are hypothesized counter adaptations that facilitate egg recognition and thus limit brood parasitism. Whether these antiparasitism strategies are maintained when the selective pressure of parasitism is relaxed remains debated. However, introduced species provide unique opportunities for testing the direction and extent of natural selection on phenotypic trait maintenance and variation. Here, we investigated egg rejection behavior and egg color polymorphism in the red-billed leiothrix (Leiothrix lutea), a common cuckoo (Cuculus canorus) host, in a population introduced to Hawaii 100 years ago (breeding without cuckoos) and a native population in China (breeding with cuckoos). We found that egg rejection ability was equally strong in both the native and the introduced populations, but levels of interclutch variation and intraclutch consistency in egg color in the native population were higher than in the introduced population. This suggests that egg rejection behavior in hosts can be maintained in the absence of brood parasitism and that egg appearance is maintained by natural selection as a counter adaptation to brood parasitism. This study provides rare evidence that host antiparasitism strategies can change under parasite-relaxed conditions and reduced selection pressure.

  3. Conspecific brood parasitism in the white-faced ibis Plegadis chihi (Aves: Pelecaniformes) revealed by microsatellites' based kinship-reconstruction.

    Science.gov (United States)

    de Castro e Souza, Andiara Silos Moraes; Del Lama, Silvia Nassif; Miño, Carolina Isabel

    2013-06-01

    The white-faced ibis Plegadis chihi Vieillot, 1817 (Pelecaniformes: Threskiornithidae) is a socially monogamous colonially breeding bird in which behavioral and ecological observations suggest the occurrence of conspecific brood parasitism (CBP). We inferred aspects of the genetic mating system of P. chihi in nature, using a genetic approach in the absence of parental information. We used five heterologous microsatellite loci and a multiple-step methodological approach to infer kinship patterns among 104 pairs of nestlings sampled inside 80 nests in a breeding colony from southern Brazil. The estimated effective population size was 69 white-faced ibises (95% CI: 50-98), enough to ensure long-term population survival. Kinship patterns were identified for 38% of the analyzed pairs: 60% of the diagnosed pairs were identified as full-siblings, 2.5% as half-siblings and 37.5% as unrelated individuals. CBP could explain the presence of unrelated nestlings within broods, in agreement with available non-genetic evidence. The presence of half-siblings within broods could indicate extra-pair paternity. Results suggest that a non-strictly monogamous genetic mating system may be present in the white-faced ibis. This study is the first molecular approach to better characterize the reproductive behavior of P. chihi in the wild. Our findings set the stage for further research to investigate the possible causes and consequences of alternative reproductive strategies in this species.

  4. Repression and recuperation of brood production in Bombus terrestris bumble bees exposed to a pulse of the neonicotinoid pesticide imidacloprid.

    Directory of Open Access Journals (Sweden)

    Ian Laycock

    Full Text Available Currently, there is concern about declining bee populations and some blame the residues of neonicotinoid pesticides in the nectar and pollen of treated crops. Bumble bees are important wild pollinators that are widely exposed to dietary neonicotinoids by foraging in agricultural environments. In the laboratory, we tested the effect of a pulsed exposure (14 days 'on dose' followed by 14 days 'off dose' to a common neonicotinoid, imidacloprid, on the amount of brood (number of eggs and larvae produced by Bombus terrestris L. bumble bees in small, standardised experimental colonies (a queen and four adult workers. During the initial 'on dose' period we observed a dose-dependent repression of brood production in colonies, with productivity decreasing as dosage increased up to 98 µg kg(-1 dietary imidacloprid. During the following 'off dose' period, colonies showed a dose-dependent recuperation such that total brood production during the 28-day pulsed exposure was not correlated with imidacloprid up to 98 µg kg(-1. Our findings raise further concern about the threat to wild bumble bees from neonicotinoids, but they also indicate some resilience to a pulsed exposure, such as that arising from the transient bloom of a treated mass-flowering crop.

  5. Repression and recuperation of brood production in Bombus terrestris bumble bees exposed to a pulse of the neonicotinoid pesticide imidacloprid.

    Science.gov (United States)

    Laycock, Ian; Cresswell, James E

    2013-01-01

    Currently, there is concern about declining bee populations and some blame the residues of neonicotinoid pesticides in the nectar and pollen of treated crops. Bumble bees are important wild pollinators that are widely exposed to dietary neonicotinoids by foraging in agricultural environments. In the laboratory, we tested the effect of a pulsed exposure (14 days 'on dose' followed by 14 days 'off dose') to a common neonicotinoid, imidacloprid, on the amount of brood (number of eggs and larvae) produced by Bombus terrestris L. bumble bees in small, standardised experimental colonies (a queen and four adult workers). During the initial 'on dose' period we observed a dose-dependent repression of brood production in colonies, with productivity decreasing as dosage increased up to 98 µg kg(-1) dietary imidacloprid. During the following 'off dose' period, colonies showed a dose-dependent recuperation such that total brood production during the 28-day pulsed exposure was not correlated with imidacloprid up to 98 µg kg(-1). Our findings raise further concern about the threat to wild bumble bees from neonicotinoids, but they also indicate some resilience to a pulsed exposure, such as that arising from the transient bloom of a treated mass-flowering crop.

  6. Comparative study of haematological, serum electrolyte and nonelectrolyte parameters of male and female Persian sturgeon (Acipenser persicus) brood stocks

    Institute of Scientific and Technical Information of China (English)

    ADEL Milad; PALANISAMY Satheesh Kumar; SHAFIEI Shafigh; FAZLI Hasan; ZORRIEHZAHRA Mohammad Jalil

    2016-01-01

    Sturgeons are the most important principal market species in the Caspian Sea. In the present study, measurement of blood parameters was carried out with the aim of evaluating the normal value of hematological and serum biochemical parameters of brood stocksAcipenser persicus during spawning season. Blood samples were collected from 36 brood stocks ofA. persicus (18 males and 18 females) during the spawning season. Higher value of red blood cells, white blood cells, haemoglobin, haematocrit was observed in male breeders with significant differences between female breeders (p>0.05). Haemoglobin and haematocrit value in this study was within the range of 8.70 to 9.2 g/dL and 29.73% to 30.26%, respectively. The statistically significant differences between mean corpuscular volumes, mean corpuscular haemoglobin, lymphocyte and neutrophil percentages, aspartate aminotransferase, alkaline phosphatase and creatine kinase were observed in the male and female brood stocks. It is concluded from this study, some of the hematological and serum biochemical parameters of male and female A. persicus breeders were significantly varied from each other. In comparative investigation with earlier reports, the values of red blood cells, haemoglobin and haematocrit are highly varied due to age variations of fish. However, further studies are necessary to understand the impact of sexual, age, size, length, and season and habitat variation. Serum biochemical parameters can be used for confirming the maturity ofA. persicus and monitoring any changes in the water quality parameters and soil.

  7. The influence of clutch and brood sizes on nesting success of the biscutate swift, Streptoprocne biscutata (Aves: Apodidae

    Directory of Open Access Journals (Sweden)

    Mauro Pichorim

    2011-04-01

    Full Text Available The nesting success of three colonies of Streptoprocne biscutata (Sclater, 1866, and the influence of clutch and brood size on nesting success of species were studied. Overall, apparent nesting success was 58% and Mayfield nesting success was 53%. Nest survival during incubation (64% was lower than during the nestling period (83%. During incubation, clutches were lost to rain, desertion, predation, egg ejection, egg damage, and egg disappearance. During the nestling period, losses occurred due to offspring disappearance, nestling death by starvation, predation and falling. During both incubation and nestling periods, predation was low, while egg ejections and nestling starvation were the main causes of nest failure. Nest survival during incubation was directly proportional to clutch size, while during the nestling period it was inversely proportional to the brood size. Apparently, there seemed to be an advantage to having more eggs during incubation. However, if all eggs were to hatch during unfavorable weather the nest success could be low. These results suggest that when the breeding pairs face adversity during incubation, they control the brood size by ejecting part of the clutch.

  8. A new case of poecilogony from South America and the implications of nurse eggs, capsule structure, and maternal brooding behavior on the development of different larval types.

    Science.gov (United States)

    Oyarzun, Fernanda X; Brante, Antonio

    2015-04-01

    Poecilogony is the production of different larval types within the same species. Although rare, poecilogonous species are ideal systems for testing the evolutionary and ecological implication of different developmental modes in marine invertebrates. Here, we described a new case of poecilogony, the Southern Hemisphere spionid Boccardia wellingtonensis. We used a combination of common-garden experiments, video recordings, and in vitro manipulations of individuals from three sites to (1) document the type of poecilogony, the brooding behavior of the mother, and the hatching process; (2) experimentally measure the effect of nurse eggs on the growth and type of larvae produced; and (3) document variation in the length of the brooding period, number of capsules, larvae, and nurse eggs of mothers from three sites to explore the potential for plasticity in reproductive traits. These results were compared to the previously reported poecilogonous species B. proboscidea, which resembles B. wellingtonensis in size, morphology, ecology, and reproductive strategy but differs in capsule structure. We found that in contrast to B. proboscidea, B. wellingtonensis produced larvae that, in isolation and in the presence of nurse eggs, developed into a wide range of offspring sizes. Mothers brood and hatch the larvae with frequent partial hatching of the brood during the brooding period. Although larvae could not liberate themselves, larvae crossed to other capsules as interconnections between capsules broke during the developmental period, potentially affecting food availability, sibling competition for nurse eggs, and cannibalism. Variation in brooding time and number of capsules deposited among sites suggest local adaptations.

  9. Reproductive-tactic-specific variation in sperm swimming speeds in a shell-brooding cichlid.

    Science.gov (United States)

    Fitzpatrick, J L; Desjardins, J K; Milligan, N; Montgomerie, R; Balshine, S

    2007-08-01

    Theory predicts that males experiencing elevated levels of sperm competition will invest more in gonads and produce faster-swimming sperm. Although there is ample evidence in support of the first prediction, few studies have examined sperm swimming speed in relation to sperm competition. In this study, we tested these predictions from sperm competition theory by examining sperm characteristics in Telmatochromis vittatus, a small shell-brooding cichlid fish endemic to Lake Tanganyika. Males exhibit four different reproductive tactics: pirate, territorial, satellite, and sneaker. Pirate males temporarily displace all other competing males from a shell nest, whereas sneaker males always release sperm in the presence of territorial and satellite males. Due to the fact that sneakers spawn in the presence of another male, sneakers face the highest levels of sperm competition and pirates the lowest, whereas satellites and territorials experience intermediate levels. In accordance with predictions, sperm from sneakers swam faster than sperm from males adopting the other reproductive tactics, whereas sperm from pirates was slowest. Interestingly, we were unable to detect any variation in sperm tail length among these reproductive tactics. Thus, sperm competition appears to have influenced sperm energetics in this species without having any influence on sperm size.

  10. Outbreaks of Virulent Infectious Bursal Disease in Flocks of Battery Cage Brooding System of Commercial Chickens

    Directory of Open Access Journals (Sweden)

    H. B. Aliyu

    2016-01-01

    Full Text Available Clinical and pathological investigations were conducted on outbreaks of infectious bursal disease (IBD in pullets under brooding using the battery cage system in a commercial poultry farm in Kaduna, Nigeria. Two consecutive outbreaks of IBD on the same farm were studied. The onset of the disease and morbidity and mortality rates were recorded. Postmortem examinations were conducted and gross lesions recorded. Tissues were collected and fixed in 10% buffered formalin and processed for histopathological examinations. In the first outbreak, 80 to 100% of the chicks were affected at the age of 4 to 5 weeks and mortality rate was 95.8% and lasted for 9 days. In the second outbreak, the mortality rate was 43.3% and it also lasted for 9 days. At the onset of the disease, the birds were also 4-week-old like in case 1. The disease was diagnosed based on clinical signs, pathology, and agar gel immunodiffusion test (AGID. Clinical signs, gross lesions, and histopathological findings were characteristic of virulent infectious bursal disease. After the first outbreak (case 1 the house was disinfected using polidine® (iodophor compound, V-ox® (inorganic peroxygen compounds, CID20® (quaternary ammonium chloride, aldehydes, and alcohol, terminator III® (phenols, and glutasan® (aldehyde and quaternary ammonium chloride. But they failed to eliminate the IBD virus from the poultry pen.

  11. Sexual imprinting and the origin of obligate brood parasitism in birds.

    Science.gov (United States)

    Slagsvold, T; Hansen, B T

    2001-10-01

    We discuss two pathways along which obligate brood parasitism (OBP) may evolve and examine some of the critical steps that must be passed by letting great tits Parus major be reared by blue tits Parus caeruleus in a field experiment. The cross-fostered chicks survived well in blue tit nests, but their local recruitment and reproductive success was much lower than that of controls. The effect was strongest when great tits grew up with siblings of the host species rather than with conspecific siblings in blue tit nests. The low success seemed to be caused by misimprinting because the cross-fostered birds behaved like blue tits in several aspects (species association, alarm calls, and aggressive response by resident females to caged intruders). Some birds of both sexes were apparently so strongly imprinted that they did not attract or accept a social mate of their own species. We conclude that imprinting may be necessary for OBP to evolve in birds because the parasite must be attracted to the nests of the host species to add eggs and thereby continue the parasitic life cycle. However, strong imprinting may also prevent OBP from occurring if parasitic offspring seek a mate from the host species.

  12. A generalist brood parasite modifies use of a host in response to reproductive success.

    Science.gov (United States)

    Louder, Matthew I M; Schelsky, Wendy M; Albores, Amber N; Hoover, Jeffrey P

    2015-09-07

    Avian obligate brood parasites, which rely solely on hosts to raise their young, should choose the highest quality hosts to maximize reproductive output. Brown-headed cowbirds (Molothrus ater) are extreme host generalists, yet female cowbirds could use information based on past reproductive outcomes to make egg-laying decisions thus minimizing fitness costs associated with parasitizing low-quality hosts. We use a long-term (21 years) nest-box study of a single host, the prothonotary warbler (Protonotaria citrea), to show that local cowbird reproductive success, but not host reproductive success, was positively correlated with the probability of parasitism the following year. Experimental manipulations of cowbird success corroborated that female cowbirds make future decisions about which hosts to use based on information pertaining to past cowbird success, both within and between years. The within-year pattern, in particular, points to local cowbird females selecting hosts based on past reproductive outcomes. This, coupled with high site fidelity of female cowbirds between years, points to information use, rather than cowbird natal returns alone, increasing parasitism rates on highly productive sites between years.

  13. Egg eviction imposes a recoverable cost of virulence in chicks of a brood parasite.

    Directory of Open Access Journals (Sweden)

    Michael G Anderson

    Full Text Available BACKGROUND: Chicks of virulent brood parasitic birds eliminate their nestmates and avoid costly competition for foster parental care. Yet, efforts to evict nest contents by the blind and naked common cuckoo Cuculus canorus hatchling are counterintuitive as both adult parasites and large older cuckoo chicks appear to be better suited to tossing the eggs and young of the foster parents. METHODOLOGY/PRINCIPAL FINDINGS: Here we show experimentally that egg tossing imposed a recoverable growth cost of mass gain in common cuckoo chicks during the nestling period in nests of great reed warbler Acrocephalus arundinaceus hosts. Growth rates of skeletal traits and morphological variables involved in the solicitation of foster parental care remained similar between evictor and non-evictor chicks throughout development. We also detected no increase in predation rates for evicting nests, suggesting that egg tossing behavior by common cuckoo hatchlings does not increase the conspicuousness of nests. CONCLUSION: The temporary growth cost of egg eviction by common cuckoo hatchlings is the result of constraints imposed by rejecter host adults and competitive nestmates on the timing and mechanism of parasite virulence.

  14. Determinants of intracolonial relatedness in Pogonomyrmex rugosus (Hymenoptera; Formicidae): mating frequency and brood raids.

    Science.gov (United States)

    Gadau, J; Strehl, C-P; Oettler, J; Hölldobler, B

    2003-07-01

    The genus Pogonomyrmex is one of three ant genera with an effective mating frequency (me) > 2.0. We developed microsatellites to determine me for P. rugosus because mating frequency of P. rugosus was known only from observational data which do not allow an estimate of me. We genotyped 474 workers from 20 colonies for two microsatellite loci. Observed mating frequencies ranged from 3 to 12 and me for P. rugosus was 4.71. Observed patriline frequencies were significantly different from the expected patriline frequencies generated with a simulated data set under the assumption of equal patriline representation. The available mating frequency data and phylogenetic information of the genus Pogonomyrmex suggest that multiple mating is the ancestral state in the North American Pogonomyrmex sensu stricto. Established P. rugosus colonies raid and destroy smaller conspecific colonies. During these raids ant workers were observed carrying pupae and larvae from the raided colony into the nest of the raiding colony. However, it was not clear whether raided brood emerged in the raiding colony and were subsequently recruited into the work force (intraspecific slavery) or were used as food (predation). Our analyses indicate 6 of 14 field colonies contained foreign P. rugosus workers (43%). The range of the intracolonial frequency of foreign workers collected directly from the nest entrance was between 4 and 28%.

  15. Genetic and Biochemical Diversity of Paenibacillus larvae Isolated from Tunisian Infected Honey Bee Broods

    Directory of Open Access Journals (Sweden)

    Chadlia Hamdi

    2013-01-01

    Full Text Available Paenibacillus larvae is the causative agent of American foulbrood (AFB, a virulent disease of honeybee (Apis mellifera larvae. In Tunisia, AFB has been detected in many beekeeping areas, where it causes important economic losses, but nothing is known about the diversity of the causing agent. Seventy-five isolates of P. larvae, identified by biochemical tests and 16S rRNA gene sequencing, were obtained from fifteen contaminated broods showing typical AFB symptoms, collected in different locations in the northern part of the country. Using BOX-PCR, a distinct profile of P. larvae with respect to related Paenibacillus species was detected which may be useful for its identification. Some P. larvae-specific bands represented novel potential molecular markers for the species. BOX-PCR fingerprints indicated a relatively high intraspecific diversity among the isolates not described previously with several molecular polymorphisms identifying six genotypes on polyacrylamide gel. Polymorphisms were also detected in several biochemical characters (indol production, nitrate reduction, and methyl red and oxidase tests. Contrary to the relatively high intraspecies molecular and phenotypic diversity, the in vivo virulence of three selected P. larvae genotypes did not differ significantly, suggesting that the genotypic/phenotypic differences are neutral or related to ecological aspects other than virulence.

  16. Local scale connectivity in the cave-dwelling brooding fish Apogon imberbis

    Science.gov (United States)

    Muths, Delphine; Rastorgueff, Pierre-Alexandre; Selva, Marjorie; Chevaldonné, Pierre

    2015-01-01

    A lower degree of population connectivity is generally expected for species living in a naturally fragmented habitat than for species living in a continuum of suitable environment. Due to clear-cut environmental conditions with the surrounding littoral zone, underwater marine caves of the Mediterranean Sea constitute a good model to explore the effect of habitat discontinuity on the population structure of their inhabitants. With this goal, the genetic population structure of Apogon imberbis, a mouth-brooding teleost, was explored using the mitochondrial cytochrome b gene and 7 nuclear microsatellite loci from 164 fishes sampled at the micro-scale (ca. 40 km) of the Marseille area (Bay of Marseille and Calanques coast, in NW Mediterranean). Both marker types indicated a low level of genetic structure within the studied area. We propose that each suitable crack and cavity is used as a stepping-stone habitat between disconnected large cave-habitats. This, together with larval dispersal, ensures enough gene flow between caves to homogenize the genetic pattern at microscale while isolation by distance and by open waters could explain the small structure observed. The present study indicates that the effect of natural fragmentation in connectivity disruption can largely be counter-balanced by life history traits and overlooked details in habitat preferences.

  17. How to evade a coevolving brood parasite: egg discrimination versus egg variability as host defences.

    Science.gov (United States)

    Spottiswoode, Claire N; Stevens, Martin

    2011-12-07

    Arms races between avian brood parasites and their hosts often result in parasitic mimicry of host eggs, to evade rejection. Once egg mimicry has evolved, host defences could escalate in two ways: (i) hosts could improve their level of egg discrimination; and (ii) negative frequency-dependent selection could generate increased variation in egg appearance (polymorphism) among individuals. Proficiency in one defence might reduce selection on the other, while a combination of the two should enable successful rejection of parasitic eggs. We compared three highly variable host species of the Afrotropical cuckoo finch Anomalospiza imberbis, using egg rejection experiments and modelling of avian colour and pattern vision. We show that each differed in their level of polymorphism, in the visual cues they used to reject foreign eggs, and in their degree of discrimination. The most polymorphic host had the crudest discrimination, whereas the least polymorphic was most discriminating. The third species, not currently parasitized, was intermediate for both defences. A model simulating parasitic laying and host rejection behaviour based on the field experiments showed that the two host strategies result in approximately the same fitness advantage to hosts. Thus, neither strategy is superior, but rather they reflect alternative potential evolutionary trajectories.

  18. Biological effects of gamma radiation on stored product insects. 4 - radiation effects on sex pheromone production and perception by the rust-red flour beetle. Tribolium castaneum (herbst)

    OpenAIRE

    Abdu, R. M.; Abdel-Kader, Maissa M.; M. A. Hussein; Abdel-Rahman, H. A.

    1985-01-01

    Irradiation of the rust-red flour beetle, T. castaneum at different doses of gamma radiation considerably affected sex pheromone production by females and perception by males. The production of sex pheromone by virgin females decreased with the increase of radiation doses from 4 to 10 krad., and a dose of 12 krad could almost inhibit pheromone production. Males were more radiosensitive in their response to sex pheromone; and a radiation dose of 8 krad could brought inhibition of male respo...

  19. Blending synthetic pheromones of cerambycid beetles to develop trap lures that simultaneously attract multiple species.

    Science.gov (United States)

    Wong, Joseph C H; Mitchell, Robert F; Striman, Becca L; Millar, Jocelyn G; Hanks, Lawrence M

    2012-06-01

    We evaluated attraction of cerambycid beetle species to blends of known cerambycid pheromones to determine whether such blends could be used as effective trap lures for detecting and monitoring multiple species simultaneously. Pheromone-baited traps captured 1,358 cerambycid beetles of which 1,101 (81.1%) belonged to three species in the subfamily Cerambycinae: Neoclytus acuminatus (F.), Neoclytus mucronatus (F.), and Xylotrechus colonus (F.). Beetles of these species were significantly attracted to synthetic blends that contained their pheromone components (isomers of 3-hydroxy-2-hexanone, 2,3-hexanediol, or both), despite the presence of pheromone components of different species, including other isomers of 2,3-hexanediol, (E/Z)-6,10-dimethyl-5,9-undecadien-2-yl acetate, and citral. In some cases, attraction was partially inhibited by the pheromone components of heterospecific species, whereas for N. acuminatus, attraction was completely inhibited when blends contained (2R*,3S*)-hexanediol, the racemic mixture of diastereomers of its pheromone, (2S,3S)-hexanediol. Among the remaining beetles captured were three species in the subfamily Lamiinae: Astyleiopus variegatus (Haldeman), Graphisurus fasciatus (Degeer), and Lepturges angulatus (LeConte). All three lamiine species were previously known to be attracted to (E/Z)-6,10-dimethyl-5,9-undecadien-2-yl acetate and were captured in significant numbers by blends containing that compound. Our results suggest that different types of cerambycid pheromones can be combined to create effective multispecies lures for use in surveillance programs that target exotic cerambycid species.

  20. The antibacterial protein lysozyme identified as the termite egg recognition pheromone.

    Directory of Open Access Journals (Sweden)

    Kenji Matsuura

    Full Text Available Social insects rely heavily on pheromone communication to maintain their sociality. Egg protection is one of the most fundamental social behaviours in social insects. The recent discovery of the termite-egg mimicking fungus 'termite-ball' and subsequent studies on termite egg protection behaviour have shown that termites can be manipulated by using the termite egg recognition pheromone (TERP, which strongly evokes the egg-carrying and -grooming behaviours of workers. Despite the great scientific and economic importance, TERP has not been identified because of practical difficulties. Herein we identified the antibacterial protein lysozyme as the TERP. We isolated the target protein using ion-exchange and hydrophobic interaction chromatography, and the MALDI-TOF MS analysis showed a molecular size of 14.5 kDa. We found that the TERP provided antibacterial activity against a gram-positive bacterium. Among the currently known antimicrobial proteins, the molecular size of 14.5 kDa limits the target to lysozyme. Termite lysozymes obtained from eggs and salivary glands, and even hen egg lysozyme, showed a strong termite egg recognition activity. Besides eggs themselves, workers also supply lysozyme to eggs through frequent egg-grooming, by which egg surfaces are coated with saliva containing lysozyme. Reverse transcript PCR analysis showed that mRNA of termite lysozyme was expressed in both salivary glands and eggs. Western blot analysis confirmed that lysozyme production begins in immature eggs in queen ovaries. This is the first identification of proteinaceous pheromone in social insects. Researchers have focused almost exclusively on hydrocarbons when searching for recognition pheromones in social insects. The present finding of a proteinaceous pheromone represents a major step forward in, and result in the broadening of, the search for recognition pheromones. This novel function of lysozyme as a termite pheromone illuminates the profound influence