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Status and mating success amongst visual artists  

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Full Text Available Geoffrey Miller has hypothesized that producing artwork functions as a mating display. Here we investigate the relationship between mating success and artistic success in a sample of 236 visual artists. We derived two measures of artistic success, one based on self-perception and the other on more objective variables to do with artistic output and attitudes, as well as a measure of artistic identity. More subjectively successful male artists and those males with a stronger artistic identity had more sexual partners than less successful artists. There was no relationship between mating success and the more objective measure of artistic status. Predicted sex differences in mating success were found for both measures of artistic success and for artistic identity. Male artists with greater self-perceived success had a mating strategy based on longer term relationships. More objective measures of success and identity did not affect mating strategy. This study may provide support for the emerging idea that our evolved psychological predispositions enable humans to construct mechanisms, such as identity, that aid our reproductive success and survival.

DanielNettle

2011-10-01

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Mating alters gene expression patterns in Drosophila melanogaster male heads  

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Full Text Available Abstract Background Behavior is a complex process resulting from the integration of genetic and environmental information. Drosophila melanogaster rely on multiple sensory modalities for reproductive success, and mating causes physiological changes in both sexes that affect reproductive output or behavior. Some of these effects are likely mediated by changes in gene expression. Courtship and mating alter female transcript profiles, but it is not known how mating affects male gene expression. Results We used Drosophila genome arrays to identify changes in gene expression profiles that occur in mated male heads. Forty-seven genes differed between mated and control heads 2 hrs post mating. Many mating-responsive genes are highly expressed in non-neural head tissues, including an adipose tissue called the fat body. One fat body-enriched gene, female-specific independent of transformer (fit, is a downstream target of the somatic sex-determination hierarchy, a genetic pathway that regulates Drosophila reproductive behaviors as well as expression of some fat-expressed genes; three other mating-responsive loci are also downstream components of this pathway. Another mating-responsive gene expressed in fat, Juvenile hormone esterase (Jhe, is necessary for robust male courtship behavior and mating success. Conclusions Our study demonstrates that mating causes changes in male head gene expression profiles and supports an increasing body of work implicating adipose signaling in behavior modulation. Since several mating-induced genes are sex-determination hierarchy target genes, additional mating-responsive loci may be downstream components of this pathway as well.

Ellis Lisa L

2010-10-01

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The Role of Ego-Identity Status in Mating Preferences  

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This study was designed to examine the role ego-identity plays in the mating preferences of late adolescents. In addition to examining the variance in mating preferences explained by ego-identity status, it was hoped that the results could assist in testing the competing Sexual Strategies (Buss & Schmitt, 1993) and Social Role (Eagly & Wood, 1999)…

Dunkel, Curtis S.; Papini, Dennis R.

2005-01-01

4

Expression of OsMATE1 and OsMATE2 alters development, stress responses and pathogen susceptibility in Arabidopsis  

Science.gov (United States)

Multidrug and Toxic compound Extrusion proteins (MATE) are a group of secondary active transporters with ubiquitous occurrences in all domains of life. This is a newly characterized transporter family with limited functional knowledge in plants. In this study, we functionally characterised two members of rice MATE gene family, OsMATE1 and OsMATE2 through expression in heterologous system, Arabidopsis. Expression of OsMATEs in Arabidopsis altered growth and morphology of transgenic plants. Genome-wide expression analysis revealed modulation of genes involved in plant growth, development and biotic stress in transgenic lines. Transgenic plants displayed sensitivity for biotic and abiotic stresses. Elevated pathogen susceptibility of transgenic lines was correlated with reduced expressions of defence related genes. Promoter and cellular localization studies suggest that both MATEs express in developing and reproductive organs and are plasma-membrane localised. Our results reveal that OsMATE1 and OsMATE2 regulate plant growth and development as well as negatively affect disease resistance. PMID:24492654

Tiwari, Manish; Sharma, Deepika; Singh, Munna; Tripathi, Rudra Deo; Trivedi, Prabodh Kumar

2014-01-01

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Abortion-prone mating influences placental antioxidant status and adversely affects placental and foetal development.  

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Abstract Oxidative stress is associated with decreased female fertility and adversely affects prenatal development. Mammalian cells have developed a network of enzymatic and non-enzymatic antioxidant defence systems to prevent oxidative stress. Little attention has been paid to the antioxidative pathways in placentas of normal and disturbed pregnancies, leaving a gap in our knowledge about the role of antioxidants in the control of foeto-placental development. The challenges in studying early human pregnancy can partly be overcome by designing animal models of abnormal pregnancy. We aimed to determine whether the antioxidant status of placentas from the CBA/J × DBA/2 abortion-prone pregnant mice differed from that of normal pregnant mice. The foetal/placental weight ratio was lower in abortion-prone matings compared with that in non-abortion-prone matings. The increased placental malondialdehyde (MDA) content, the end products of lipid peroxidation, with concomitants alterations in placental antioxidants, namely copper-zinc containing superoxide dismutase (SOD1), manganese containing (SOD2), glutathione peroxidases (GPX), glutathione reductase (GR) and catalase (CAT) activities may be involved in placental and foetal growth restriction. We show that placental oxidative stress is linked with poor prenatal development and pregnancy losses in CBA/J × DBA/2 mice matings. This animal model may be useful in the evaluation of nutritional antioxidant therapies for oxidative stress and associated prenatal developmental disorders. PMID:25263566

Al-Gubory, K H; Krawiec, A; Grange, S; Faure, P; Garrel, C

2014-12-01

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Mating pheromone-induced alteration of cell surface proteins in the heterobasidiomycetous yeast Tremella mesenterica.  

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Mating pheromone-induced alteration of the cell surface proteins of haploid cells, presumed to play crucial roles in the specific cell-cell interactions during sexual conjugation of Tremella mesenterica , was investigated. Exposed surface proteins were revealed by lactoperoxidase-catalyzed iodination in combination with polyacrylamide gel electrophoresis and autoradiography. From comparison of the molecular species of 125I-labeled surface proteins of the vegetative and the gamete (mating pher...

Miyakawa, T.; Kadota, T.; Okubo, Y.; Hatano, T.; Tsuchiya, E.; Fukui, S.

1984-01-01

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Mate retention tactics in Spain: personality, sex differences, and relationship status.  

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Mate retention is an important problem in romantic relationships because of mate poachers, infidelity, and the risk of outright defection. The current study (N=892) represents the first study of mate retention tactics conducted in Spain. We tested hypotheses about the effects of gender, relationship commitment status, and personality on mate retention tactics. Women and men differed in the use of resource display, appearance enhancement, intrasexual violence, and submission/self-abasement as mate retention tactics. Those in more committed relationships reported higher levels of resource display, appearance enhancement, love, and verbal signals of possession. Those in less committed relationships more often reported intentionally evoking jealousy in their partner as a mate retention tactic. Personality characteristics, particularly Neuroticism and Agreeableness, correlated in coherent ways with mate retention tactics, supporting two evolution-based hypotheses. Discussion focuses on the implications, future research directions, and interdisciplinary syntheses emerging between personality and social psychology and evolutionary psychology. PMID:21534964

de Miguel, Adelia; Buss, David M

2011-06-01

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The Treatment of Relationship Status in Research on Dating and Mate Selection  

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The relationship status of study participants (e.g., daters, cohabitors, marrieds, or unmarrieds) has implications for understanding dating and mate selection. Procedures used in studies may blur or ignore status distinctions. The authors examined methods used in 791 studies published from 1991-2001. Most commonly, status of participants is…

Surra, Catherine A; Boettcher-Burke, Tyfany M. J.; Cottle, Nathan R.; West, Adam R.; Gray, Christine R.

2007-01-01

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Sexual selection on Drosophila serrata male pheromones does not vary with female age or mating status.  

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Mate preferences are costly and are thought to evolve due to the direct and/or indirect benefits they provide. Such costs and benefits may vary in response to intrinsic and extrinsic factors with important evolutionary consequences. Limited attention has been given to quantifying such variation and understanding its causes, most notably with respect to the direction and strength of preferences for multivariate sexual displays. In Drosophila serrata, female preferences target a pheromone blend of long-chain cuticular hydrocarbons (CHCs). We used a factorial design to test whether female age and mating status generated variation in the strength and direction of sexual selection on male CHCs. Replicate choice mating trials were conducted using young and old females (4 or 10 days post-emergence) that were either virgin or previously mated. The outcome of such trials is known to capture variation in female mate preferences, although male-male interactions may also contribute. Directional sexual selection on male CHCs was highly significant within each treatment, but there was little evidence of any variation among treatments. The absence of treatment effects implies that the multivariate combination of male CHCs preferred by females was constant with respect to female age and mating status. To the extent that male-male interactions may also contribute, our results similarly imply that these did not vary among treatments groups. With respect to D. serrata mate preferences, our results suggest that either plasticity with respect to age and mating status is not beneficial to females, or preference expression is somehow constrained. PMID:24828752

Gershman, S; Delcourt, M; Rundle, H D

2014-06-01

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Audience Effect Alters Male Mating Preferences in Zebra Finches (Taeniopygia guttata)  

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The social environment of animals strongly influences the mating preferences of both the choosing and the observing individuals. Notably, there is recent evidence that polygamous males decrease their selectivity when being observed by competitors in order to direct their rivals’ attention away from their true interest and, consequently, reduce sperm competition risk. Yet, other mechanisms, whose importance remains unexplored, could induce similar effects. In monogamous species with mutual choice, particularly, if males adjust their selectivity according to the risk of being rejected by their preferred mate, they should as well become less selective when potential rivals are present. Here, we investigated whether the presence of bystanders modifies male mating preferences when the risk of sperm competition is low, by carrying out mate-choice experiments with male zebra finches (Taeniopygia guttata) whose preferences for two females were measured twice: with and without an audience. We found that the presence of potential rivals had no effect on the males’ choosiness. However, with an audience, they spent more time with the female that was considered as the less attractive one in the control condition. These findings support the hypothesis that monogamous males alter their mate choice decisions in the presence of a male audience to reduce the risk of remaining unpaired. Thus, our results indicate that several explanations can account for the changes in male preferences due to the presence of competitors and highlight the importance of assessing the relative role of each mechanism potentially involved, to be able to make conclusions about the effect of an audience on signal evolution. PMID:22916298

Dubois, Frederique; Belzile, Alexandra

2012-01-01

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Assessment of the altered mental status patient.  

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Patients presenting with an altered mental status are a fairly common event for the EMS provider. Much of the uncertainty in etiology and the ambiguity in defining the clinical presentation can be minimized with a good understanding of the common pathology associated with AMS and applying a well-organized, thorough approach to assessing these patients. Recognizing the differences between cognition and arousal and correlating the anatomical functions of the brain to the symptom presentation help considerably in understanding the causes of AMS. Classifying causes as arising from a structural nature or attributing the AMS to either a metabolic or a toxic source are fundamental in understanding potential etiologies. In assessing and reporting clinical findings, it is important to eliminate collective phrases to represent the patient's mental status and, instead, describe the patient's behavior and responses to stimuli. Complying with a standardized approach to assessment and employing effective assessment aids (such as AVPU or SAMPLE) help to prevent omissions of relevant data and contribute to a comprehensive assessment. With these goals in mind, the emergency care provider can effectively assess and manage patients with altered mental status with confidence and precision, and in a comprehensive manner. PMID:11925639

Limmer, Daniel; Monosky, Keith

2002-03-01

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The relevance of age and nutritional status on the mating competitiveness of medfly males (Diptera: Teprhitidae)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Results of previous investigations trying to ascertain which physiological factors are more important to the mating success of medfly males are controversial. In part, this controversy owes to the fact that each factor was evaluated by an independent study using different experimental designs and po [...] pulations. In the present study we compare the roles of age and nutritional status (immature and adult phases) on the mating competitiveness of Ceratitis capitata (Wiedemann, 1824) males. Three parameters were used to evaluate the male mating success: calling behavior (pheromone emission), lek participation and copulation (ability to be chosen by a female). Females gave preference to the males that were given a high protein diet in the larval phase. By contrast, females did not give preference to males that had been well-nourished in the adult phase only. The other parameters evaluated followed the same pattern: young males and males that had been fed a high protein diet during their immature phase had a greater participation in leks and called more often than older males and males that had been fed a diet poor in protein during their larval phase. Therefore, we conclude that the mating success of C. capitata males is determined both by age and nourishment during the immature stage.

Alzira Kelly Passos, Roriz; Iara Sordi, Joachim-Bravo.

2013-10-01

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Alterations of redox-status during psoriasis.  

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The skin is constantly exposed to oxidative stress induced by reactive oxygen species (ROS) that are generated both from endogenous neutrophils and external pro-oxidant stimuli. The present study was planned to investigate the possible involvement of free radical oxidation in psoriatic patients. Study was carried out in the Department of Dermatology and Venereology in Tbilisi State Medical University. A total of 60 individuals were included in this study, out of these 40 were patients suffering from psoriasis and 20 were healthy subjects (a control). Psoriasis patients were further graded according to the Psoriasis Area Severity Index (PASI); in patients' blood redox-status superoxide (O2-) and lipoperoxide (LOO.) free radicals, free Mn2+-ions and (ceruloplasmin/Fe3+-transferrin) system antioxidant activity were estimated by Electron Paramagnetic Resonance (EPR) method and activity of catalase (CAT) and superoxide dismutase (SOD) were determined by spectrophotometry. In the blood of patients with psoriasis, the EPR signal intensities of oxidized form ceruloplasmin (Cp) increased and ferrum-transport protein, Fe3+-transferrin (Fe3+-Tr) decreased in comparison to the same parameters of healthy persons. Activity of blood catalase increased and activity of blood SOD decreased with increasing severity of psoriasis. EPR signals of low-molecular Mn2+-containing complexes and lipoperoxide (LOO.) free radicals were detected. The obtained data indicate the alteration of blood redox-balance during psoriasis; the intensity of impairment of redox balance correlates with severity of psoriasis. PMID:25214274

Matoshvili, M; Katsitadze, A; Sanikidze, T; Tophuria, D; Richetta, A; D'Epiro, S

2014-01-01

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Variation in adult sex ratio alters the association between courtship, mating frequency and paternity in the lek-forming fruitfly Ceratitis capitata.  

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The intensity with which males deliver courtship and the frequency with which they mate are key components of male reproductive success. However, we expect the strength of the relationship between these traits and a male's overall paternity to be strongly context dependent, for example to be altered significantly by the extent of post-mating competition. We tested this prediction in a lekking insect, Ceratitis capitata (medfly). We examined the effect of manipulating the sex ratio from male- to female-biased (high and low male competition, respectively) on courtship behaviour, mating frequency and paternity of focal males. Under high male competition, focal males delivered significantly more courtship but gained lower paternity than under lower competition. Paternity was positively associated with mating frequency and small residual testes size. However, the association between mating frequency and paternity was significantly stronger under low competition. We conclude that manipulation of sex ratio significantly altered the predictors of mating success and paternity. The relationship between pre- and post-mating success is therefore plastic and alters according to the prevailing level of competition. The results highlight the importance of post-copulatory processes in lekking species and illuminate selection pressures placed on insects such as medflies that are mass reared for pest control. PMID:22725666

Leftwich, P T; Edward, D A; Alphey, L; Gage, M J G; Chapman, T

2012-09-01

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MealMate: improving the nutritional status of elders using a milk-based nutritional supplement.  

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MealMate was a longitudinal research project conducted by the staff at the Geriatric Health Institute, a joint venture between Sioux Valley Hospital and the University of South Dakota School of Medicine. During Fall 1994, 64 older adults enrolled in this nutrition study at a Sioux Falls congregate dining site and drank a half-pint of whole milk combined with Carnation Instant Breakfast daily for one month. Pre-test and post-test data collected included anthropometric measures, specific blood tests from a venipuncture blood draw and use of standardized instruments to assess nutritional risk, depression, mental status and general demographic information. Results suggest that a longitudinal study with elders can be done effectively (attrition rate of less than 11%). While elders were very healthy at the onset, they nevertheless showed improved nutritional status over time. Laboratory tests showed significant increases in Vitamin D levels in adults over age 79. Using a more malnourished, home-bound sample of elders over age 79 and adding only whole milk to their diets are discussed as possible considerations for future research. PMID:7481725

Schrader, S L; Schrank, M; Blue, R; Zawada, E T; Trujillo, A L; Alvai, F K

1995-09-01

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Organic and Conventional Yerba Mate (Ilex paraguariensis A. St. Hil Improves Metabolic Redox Status of Liver and Serum in Wistar Rats  

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Full Text Available Organic and conventional yerba mate (Ilex paraguariensis is widely used in South America to prepare nonalcoholic drinks rich in polyphenols. These compounds are able to prevent the generation of reactive species, thus minimizing the incidence of several diseases. In this perspective, we hypothesized that yerba mate may have protective effects against pentylenetetrazol (PTZ-induced oxidative damage in liver and serum of rats. Animals (n = 42 received distilled water (control or yerba mate (organic or conventional for fifteen days. Then, half of the rats of each group received 60 mg/kg PTZ intraperitoneally or saline solution. After 30 min the animals were euthanized and the liver and blood were collected. The results showed that organic and conventional yerba mate avoided PTZ-induced oxidative damage and nitric oxide production in the liver and serum of the rats. Moreover, both kinds of yerba mate prevented the decrease in enzymatic (superoxide dismutase and catalase and non-enzymatic (sulfhydryl protein content defenses in the liver and serum. In addition, histopathologic analysis of the liver showed that yerba mate reduced PTZ-induced cell damage. These findings indicate that yerba mate provides hepatoprotection and improves antioxidant status in the serum, which may contribute to the development of new therapeutic strategies using nutraceuticals drinks.

Cátia S. Branco

2013-07-01

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Male mating biology  

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Full Text Available Abstract Before sterile mass-reared mosquitoes are released in an attempt to control local populations, many facets of male mating biology need to be elucidated. Large knowledge gaps exist in how both sexes meet in space and time, the correlation of male size and mating success and in which arenas matings are successful. Previous failures in mosquito sterile insect technique (SIT projects have been linked to poor knowledge of local mating behaviours or the selection of deleterious phenotypes during colonisation and long-term mass rearing. Careful selection of mating characteristics must be combined with intensive field trials to ensure phenotypic characters are not antagonistic to longevity, dispersal, or mating behaviours in released males. Success has been achieved, even when colonised vectors were less competitive, due in part to extensive field trials to ensure mating compatibility and effective dispersal. The study of male mating biology in other dipterans has improved the success of operational SIT programmes. Contributing factors include inter-sexual selection, pheromone based attraction, the ability to detect alterations in local mating behaviours, and the effects of long-term colonisation on mating competitiveness. Although great strides have been made in other SIT programmes, this knowledge may not be germane to anophelines, and this has led to a recent increase in research in this area.

Howell Paul I

2009-11-01

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Roles of olfactory cues, visual cues, and mating status in orientation of Diaphorina citri Kuwayama (Hemiptera: Psyllidae) to four different host plants.  

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Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is an important worldwide pest of citrus that vectors bacteria (Candidatus Liberibacter spp.) responsible for huanglongbing (citrus greening disease). We examined the behavioral responses of mated and unmated D. citri of both sexes to odors from host plants in a Y-tube olfactometer, with and without visual cues. The host plants tested were 'Duncan' grapefruit (Citrus paradisi Macfayden), sour orange (Citrus aurantium L.), navel orange (C. sinensis L.), and Murraya paniculata L. Jack. Responses varied by plant species, psyllid sex and mating status, and the presence of a visual cue. Evidence of attraction generally was stronger in females and in mated individuals of both sexes relative to virgins. The presence of a visual cue typically enhanced attractiveness of olfactory cues; in no case did unmated individuals show evidence of attraction to host plant odors in the absence of avisual cue. In the absence of visual cues, mated females and males showed evidence of attraction only to odors from sour orange and navel orange, respectively. Psyllids exhibited anemotactic responses when assayed with plant odors alone but showed strong evidence of attraction only when olfactory and visual cues were combined, suggesting that olfactory cues facilitate orientation to host plants but may be insufficient alone. Antennal responses to citrus volatiles were confirmed by electroantennogram. The results reported here provide evidence that D. citri uses olfactory and visual cues in orientation to host plants and suggest the possibility of using plant volatiles in monitoring and management of this pest. PMID:19791618

Wenninger, Erik J; Stelinski, Lukasz L; Hall, David G

2009-02-01

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Massive nest-box supplementation boosts fecundity, survival and even immigration without altering mating and reproductive behaviour in a rapidly recovered bird population.  

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Habitat restoration measures may result in artificially high breeding density, for instance when nest-boxes saturate the environment, which can negatively impact species' demography. Potential risks include changes in mating and reproductive behaviour such as increased extra-pair paternity, conspecific brood parasitism, and polygyny. Under particular cicumstances, these mechanisms may disrupt reproduction, with populations dragged into an extinction vortex. With the use of nuclear microsatellite markers, we investigated the occurrence of these potentially negative effects in a recovered population of a rare secondary cavity-nesting farmland bird of Central Europe, the hoopoe (Upupa epops). High intensity farming in the study area has resulted in a total eradication of cavity trees, depriving hoopoes from breeding sites. An intensive nest-box campaign rectified this problem, resulting in a spectacular population recovery within a few years only. There was some concern, however, that the new, high artificially-induced breeding density might alter hoopoe mating and reproductive behaviour. As the species underwent a serious demographic bottleneck in the 1970-1990s, we also used the microsatellite markers to reconstitute the demo-genetic history of the population, looking in particular for signs of genetic erosion. We found i) a low occurrence of extra-pair paternity, polygyny and conspecific brood parasitism, ii) a high level of neutral genetic diversity (mean number of alleles and expected heterozygosity per locus: 13.8 and 83%, respectively) and, iii) evidence for genetic connectivity through recent immigration of individuals from well differentiated populations. The recent increase in breeding density did thus not induce so far any noticeable detrimental changes in mating and reproductive behaviour. The demographic bottleneck undergone by the population in the 1970s-1990s was furthermore not accompanied by any significant drop in neutral genetic diversity. Finally, genetic data converged with a concomitant demographic study to evidence that immigration strongly contributed to local population recovery. PMID:22545155

Berthier, Karine; Leippert, Fabio; Fumagalli, Luca; Arlettaz, Raphaël

2012-01-01

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The influence of mating status and age on the induction of chromosome aberrations and dominant lethals in irradiated female mice  

International Nuclear Information System (INIS)

Young and old hybrid female mice were given 0.5 Gy or 2 Gy acute X-irradiation, followed by (i) in utero examination for dominant lethal mutations, or (ii) examination of metaphase I oocytes for chromosome aberrations 2-3 weeks after the irradiation. Some of the old females had been mated when young to males of a specific locus stock. Others were left unmated until after the irradiation when they, and the young females, were mated to the same specific locus stock and allowed to have 1 (if given 2 Gy) or 2 (if given 0.5 Gy) litters before the dominant lethal test. In both the 0.5-Gy and 2-Gy series, mean sizes of first litters in the old late-mated group were markedly lower than in the old early-mated or young groups, the differences being significant at the 2-Gy level. The intrauterine examinations showed that this difference was largely the result of a reduced ovulation rate in the old late-mated females. (Auth.)

 
 
 
 
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Is the Oxidant/Antioxidant Status Altered in CADASIL Patients?  

Science.gov (United States)

The altered aggregation of proteins in non-native conformation is associated with endoplasmic reticulum derangements, mitochondrial dysfunction and excessive production of reactive oxygen species. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary systemic vasculopathy, caused by NOTCH3 mutations within the receptor extracellular domain, that lead to abnormal accumulation of the mutated protein in the vascular wall. NOTCH3 misfolding could cause free radicals increase also in CADASIL. Aim of the study was to verify whether CADASIL patients have increased oxidative stress compared to unrelated healthy controls. We enrolled 15 CADASIL patients and 16 gender- and age-matched healthy controls with comparable cardiovascular risk factor. Blood and plasma reduced and total aminothiols (homocysteine, cysteine, glutathione, cysteinylglycine) were measured by HPLC and plasma 3-nitrotyrosine by ELISA. Only plasma reduced cysteine (Pr-Cys) and blood reduced glutathione (Br-GSH) concentrations differed between groups: in CADASIL patients Br-GSH levels were higher (p = 0.019) and Pr-Cys lower (p = 0.010) than in controls. No correlation was found between Br-GSH and Pr-Cys either in CADASIL patients (rho 0.25, P=0.36) or in controls (rho -0.15, P=0.44). Conversely, 3-nitrotyrosine values were similar in CADASIL and healthy subjects (p = 0.82). The high levels of antioxidant molecules and low levels of oxidant mediators found in our CADASIL population might either be expression of an effective protective action against free radical formation at an early stage of clinical symptoms or they could suggest that oxidative stress is not directly involved in the pathogenesis of CADASIL. PMID:23799141

Campolo, Jonica; De Maria, Renata; Mariotti, Caterina; Tomasello, Chiara; Parolini, Marina; Frontali, Marina; Inzitari, Domenico; Valenti, Raffaella; Federico, Antonio; Taroni, Franco; Parodi, Oberdan

2013-01-01

22

Is the oxidant/antioxidant status altered in CADASIL patients?  

Science.gov (United States)

The altered aggregation of proteins in non-native conformation is associated with endoplasmic reticulum derangements, mitochondrial dysfunction and excessive production of reactive oxygen species. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary systemic vasculopathy, caused by NOTCH3 mutations within the receptor extracellular domain, that lead to abnormal accumulation of the mutated protein in the vascular wall. NOTCH3 misfolding could cause free radicals increase also in CADASIL. Aim of the study was to verify whether CADASIL patients have increased oxidative stress compared to unrelated healthy controls. We enrolled 15 CADASIL patients and 16 gender- and age-matched healthy controls with comparable cardiovascular risk factor. Blood and plasma reduced and total aminothiols (homocysteine, cysteine, glutathione, cysteinylglycine) were measured by HPLC and plasma 3-nitrotyrosine by ELISA. Only plasma reduced cysteine (Pr-Cys) and blood reduced glutathione (Br-GSH) concentrations differed between groups: in CADASIL patients Br-GSH levels were higher (p = 0.019) and Pr-Cys lower (p = 0.010) than in controls. No correlation was found between Br-GSH and Pr-Cys either in CADASIL patients (rho 0.25, P = 0.36) or in controls (rho -0.15, P = 0.44). Conversely, 3-nitrotyrosine values were similar in CADASIL and healthy subjects (p = 0.82). The high levels of antioxidant molecules and low levels of oxidant mediators found in our CADASIL population might either be expression of an effective protective action against free radical formation at an early stage of clinical symptoms or they could suggest that oxidative stress is not directly involved in the pathogenesis of CADASIL. PMID:23799141

Campolo, Jonica; De Maria, Renata; Mariotti, Caterina; Tomasello, Chiara; Parolini, Marina; Frontali, Marina; Inzitari, Domenico; Valenti, Raffaella; Federico, Antonio; Taroni, Franco; Parodi, Oberdan

2013-01-01

23

Heliothis zea (Lepidoptera: Noctuidae): effects of radiation and inherited sterility on mating competitiveness  

International Nuclear Information System (INIS)

Normal and irradiated laboratory-reared Heliothis zea (Boddie) moths were released in screened field cages and in fields of tobacco and cotton. The nocturnal activities and incidence of mating of laboratory-reared and wild moths were observed. Laboratory-reared moths irradiated with 10 krad and released in field cages were competitive with nonirradiated laboratory-reared moths. The competitiveness of irradiated moths was not altered by the time interval (5 and 30 h) between irradiation and release, the mating status of the male, or by the time interval (24 and 48 h) between mating and release. Normal and irradiated, laboratory-reared males released in the field in either the presence or absence of laboratory-reared females were not significantly different in their nocturnal behavior and mating competitiveness. The interaction of wild and laboratory-reared moths was largely limited to wild males mating with laboratory-reared females

24

Juvenile hormone catabolism and oviposition in the codling moth, Cydia pomonella, as functions of age, mating status, and hormone treatment.  

Science.gov (United States)

In vitro catabolism of juvenile hormone (JH) in haemolymph of adult female Cydia pomonella was ascribed mainly to juvenile hormone esterase (JHE) activity. No significant differences were noted between virgin and mated females 0-96 h post-emergence. Changes in JHE activity did not appear dependent upon fluctuations in JH titre; conversely, changes in JHE activity could not explain the changes in JH titres. Maximal JHE activity was recorded at 24 h (331.47 +/- 47.25 pmol/h/microl; 355.93 +/- 36.68 pmol/h/microl, virgin; mated insects, respectively) and preceded the peak in JH titres at 48 h. Topical application of JH II (10 ng-10 microg) or fenoxycarb (50 ng) enhanced JHE activity up to 640 and 56%, respectively. Treatment upon emergence with 10 microg JH II induced enzymic activity for less than 24 h, and when 10 microg JH II or 50 ng fenoxycarb were applied, circulating JH titres returned to control levels within 24 h. Oviposition was highly sensitive to exogenous JH and declined significantly with dosages >100 pg. To allow a degree of oocyte maturation before JH treatment, the hormone was administered at 6, 12, 24, or 48 h post-emergence and/or females were mated. Neither measure "protected" the system; oviposition declined immediately after JH application. PMID:11754090

Cole, Tracey J; Ramaswamy, Sonny B; Srinivasan, Asoka; Dorn, Silvia

2002-01-01

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Individual differences in valuing mates' physical attractiveness.  

Science.gov (United States)

To investigate correlates of valuing physical attractiveness in a mate, it was hypothesized that valuing physical attractiveness in a mate would correlate with sex and valuing promiscuous sex, status, personal physical attractiveness, beauty, and order. Men and women college students completed measures of the extent to which they valued physical attractiveness in a mate and other variables. Valuing physical attractiveness in a mate was correlated with sex (men valued physical attractiveness in a mate more than did women) and valuing promiscuous sex and status, and, for women, valuing personal physical attractiveness. The results were explained in terms of evolutionary theory. PMID:17153821

Mathes, Eugene W; Bielser, Abby; Cassell, Ticcarra; Summers, Sarah; Witowski, Aggie

2006-10-01

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The value of electroencephalography in differential diagnosis of altered mental status in emergency departments  

International Nuclear Information System (INIS)

Objective: To evaluate the value of electroencephalography in patients with altered mental status in emergency departments. Methods: Demographical characteristics, types and aetiologies of seizures, and clinical outcomes of the patients were recorded. Patients were divided into 4 groups according to the complaints of admission: findings and symptoms of seizure; stroke and symptoms of stroke-related seizures; syncope; and metabolic abnormalities and other causes of altered mental status. The electroencephalography findings were classified into 3 groups: epileptiform discharges; paroxysmal electroencephalography abnormalities; and background slowing. Electroencephalography abnormalities in each subgroup were evaluated. SPSS 21 was used for statistical analysis. Results: Of the total 190 patients in the study, 117(61.6%) had pathological electroencephalography findings. The main reason for electroencephalography in the emergency department was the presence of seizure findings and symptoms in 98(51.6%) patients. The ratio of electroencephalography abnormality was higher in patients who were admitted with complaints of metabolic abnormality-related consciousness disturbances (p<0.001). A total of 124(65.3%) patients had neuroimagings. Electroencephalography abnormalities were found to be significantly higher in patients with neuroimagings compared to those without neuroimagings (p<0.003). Conclusion: Despite advanced neuroimaging techniques, electroencephalography is still an important tool in the differential diagnosis of altered mental status such as epileptic seizures, metabolic abnormalities, pseudo-seizures and syncope. (author)

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Mate preferences do predict attraction and choices in the early stages of mate selection.  

Science.gov (United States)

Although mate preference research has firmly established that men value physical attractiveness more than women do and women value social status more than men do, recent speed-dating studies have indicated mixed evidence (at best) for whether people's sex-differentiated mate preferences predict actual mate choices. According to an evolutionary, mate preference priority model (Li, Bailey, Kenrick, & Linsenmeier, 2002; Li & Kenrick, 2006; Li, Valentine, & Patel, 2011), the sexes are largely similar in what they ideally like, but for long-term mates, they should differ on what they most want to avoid in early selection contexts. Following this model, we conducted experiments using online messaging and modified speed-dating platforms. Results indicate that when a mating pool includes people at the low end of social status and physical attractiveness, mate choice criteria are sex-differentiated: Men, more than women, chose mates based on physical attractiveness, whereas women, more than men, chose mates based on social status. In addition, individuals who more greatly valued social status or physical attractiveness on paper valued these traits more in their actual choices. In particular, mate choices were sex-differentiated when considering long-term relationships but not short-term ones, where both sexes shunned partners with low physical attractiveness. The findings validate a large body of mate preferences research and an evolutionary perspective on mating, and they have implications for research using speed-dating and other interactive contexts. PMID:23915041

Li, Norman P; Yong, Jose C; Tov, William; Sng, Oliver; Fletcher, Garth J O; Valentine, Katherine A; Jiang, Yun F; Balliet, Daniel

2013-11-01

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Mating Game  

Science.gov (United States)

In this game (on pages 14-21), learners explore how each human being inherits genetic traits such as eye color. Learners use "Smiley Mother's Genes" cards and "Smiley Father's Genes" cards to "mate" them into a Smiley Face Baby that the learner draws. The Mating Game Results page shows how the pairs translate into features such as face, eye, and mouth shape, skin color, hair type, and sex. The Thinking It Over section asks questions about how learners would feel if their baby had "Upsidedown Smile Syndrome," which can open up a discussion about genetic engineering.

Museum, University O.; Nebraska Cooperative Extension 4-H Youth Development

2002-01-01

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Altered redox status of coenzyme Q9 reflects mitochondrial electron transport chain deficiencies in Caenorhabditis elegans.  

Science.gov (United States)

Mitochondrial disorders are often associated with primary or secondary CoQ10 decrease. In clinical practice, Coenzyme Q10 (CoQ10) levels are measured to diagnose deficiencies and to direct and monitor supplemental therapy. CoQ10 is reduced by complex I or II and oxidized by complex III in the mitochondrial respiratory chain. Therefore, the ratio between the reduced (ubiquinol) and oxidized (ubiquinone) CoQ10 may provide clinically significant information in patients with mitochondrial electron transport chain (ETC) defects. Here, we exploit mutants of Caenorhabditis elegans (C. elegans) with defined defects of the ETC to demonstrate an altered redox ratio in Coenzyme Q9 (CoQ9), the native quinone in these organisms. The percentage of reduced CoQ9 is decreased in complex I (gas-1) and complex II (mev-1) deficient animals, consistent with the diminished activity of these complexes that normally reduce CoQ9. As anticipated, reduced CoQ9 is increased in the complex III deficient mutant (isp-1), since the oxidase activity of the complex is severely defective. These data provide proof of principle of our hypothesis that an altered redox status of CoQ may be present in respiratory complex deficiencies. The assessment of CoQ10 redox status in patients with mitochondrial disorders may be a simple and useful tool to uncover and monitor specific respiratory complex defects. PMID:20849980

Vasta, V; Sedensky, M; Morgan, P; Hahn, S H

2011-01-01

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Strategies of Human Mating  

Directory of Open Access Journals (Sweden)

Full Text Available Modern humans have inherited the mating strategies that led to the success of their ancestors. These strategies include long-term mating, short-term mating, extra-pair mating, mate poaching, and mate guarding. This article presents empirical evidence supporting evolution-based hypotheses about the complexities of these mating strategies. Since men and women historically confronted different adaptive problems in the mating domain, the sexes differ profoundly in evolved strategic solutions. These differences include possessing different mate preferences, different desires for short-term mating, and differences in the triggers that evoke sexual jealousy. The study of human mating is one of the “success stories” of evolutionary psychology.

David M. Buss

2006-12-01

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Strategies of Human Mating  

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Modern humans have inherited the mating strategies that led to the success of their ancestors. These strategies include long-term mating, short-term mating, extra-pair mating, mate poaching, and mate guarding. This article presents empirical evidence supporting evolution-based hypotheses about the complexities of these mating strategies. Since men and women historically confronted different adaptive problems in the mating domain, the sexes differ profoundly in evolved strategic solutions. The...

Buss, David M.

2006-01-01

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Grasshoppers mating  

Science.gov (United States)

Unlike plants, animals are able to move around and find mates to reproduce with. The male grasshopper deposits his sperm (like pollen on a carpel) inside the female which fertilizes her eggs. The female then lays her eggs containing a growing embryo and waits for them to hatch.

Katie Hale (CSUF;Biological Sciences)

2007-06-19

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Balanced anesthesia with sevoflurane does not alter redox status in patients undergoing surgical procedures.  

Science.gov (United States)

Despite the effectiveness and safety of anesthetics, some unanswered questions remain concerning their toxicity and effects on cellular redox balance. To test for possible toxic effects of balanced anesthesia maintained with the volatile anesthetic sevoflurane, we evaluated oxidative stress during and after general anesthesia in 15 adult patients without comorbidities who underwent elective minor surgical procedures. Venous blood samples were collected at baseline, before anesthesia (t0); after anesthesia induction and immediately before surgery (t1); 2h after the beginning of anesthesia (t2); and on the day following surgery (t3). Antioxidant defense was determined by fluorometry. Oxidative stress markers included oxidative DNA damage, evaluated by the alkaline comet assay, and plasma malondialdehyde (MDA), assessed by high performance liquid chromatography (HPLC). No increase in oxidized DNA damage or antioxidant defense was observed. Plasma MDA increased only at t3 compared with t2. Balanced sevoflurane-maintained anesthesia appears neither to damage DNA nor to alter redox status. PMID:25308703

Orosz, José Eduardo B; Braz, Leandro G; Ferreira, Ana Lucia A; Amorim, Rosa Beatriz; Salvadori, Daisy Maria F; Yeum, Kyung-Jin; Braz, José Reinaldo C; Braz, Mariana G

2014-10-01

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Altered oxidant-antioxidant status in non-obese men with moderate essential hypertension  

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Full Text Available Background : Although a wide number of experimental evidences are available regarding oxidant-antioxidant disturbance in hypertension, clinical data supporting it is lacking in men in early stages of hypertension. Aims: The objective of the study was to evaluate oxidative status and antioxidant activities in males with stage I essential hypertension. Materials and Methods : Thirty hypertensives and 21 normotensives were included in the study. Protein carbonyl, reduced glutathione, glutathione peroxidase, catalase and fasting glucose were assessed in both the groups. Statistical Analysis : Results were analyzed by student?s ?t? test and linear regression analysis test. Results : Plasma protein carbonyl and glutathione peroxidase were significantly increased, and catalase and GSH were significantly reduced in the hypertensive group compared to normotensive subjects. There was a significant negative correlation between glutathione peroxidase and catalase in the test group. Conclusions : The data from the present study indicates an alteration in oxidant-antioxidant status in non-obese men in early stages of essential hypertension.

Nandeesha H

2007-06-01

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Reversible inactivation of alpha-ketoglutarate dehydrogenase in response to alterations in the mitochondrial glutathione status.  

Science.gov (United States)

In a previous study, we found that treatment of rat heart mitochondria with H(2)O(2) resulted in a decline and subsequent recovery in the rate of state 3 NADH-linked respiration. These effects were shown to be mediated by reversible alterations in NAD(P)H utilization and in the activities of specific Krebs cycle enzymes alpha-ketoglutarate dehydrogenase (KGDH) and succinate dehydrogenase. The purpose of the current study was to examine potential mechanism(s) by which H(2)O(2) reversibly alters KGDH activity. We report here that inactivation is not simply due to direct interaction of H(2)O(2) with KGDH. In addition, incubation of mitochondria with deferroxamine, an iron chelator, or 1,3-dimethyl-2-thiourea, an oxygen radical scavenger, prior to addition of H(2)O(2) did not alter the rate or extent of inactivation. Thus, inactivation does not appear to involve a more potent oxygen radical formed upon metal-catalyzed oxidation. Inactive KGDH from H(2)O(2)-treated mitochondria was reactivated with dithiothreitol, implicating oxidation of a protein sulfhydryl(s). However, the thioredoxin system had no effect, indicating that enzyme inactivation is not due to the formation of intra- or intermolecular disulfide(s) or a sulfenic acid. Upon incubation of mitochondria with H(2)O(2), reduced GSH levels fell rapidly prior to enzyme inactivation but recovered at the same time as enzyme activity. Importantly, treatment of inactive KGDH with glutaredoxin facilitated the GSH-dependent recovery of KGDH activity. Glutaredoxin is characterized as a specific and efficient catalyst of protein deglutathionylation. Thus, the results of the current study indicate that KGDH activity appears to be modulated through enzymatic glutathionylation and deglutathionylation. These studies demonstrate a novel mechanism by which KGDH activity and mitochondrial function can be modulated by redox status. PMID:12680778

Nulton-Persson, Amy C; Starke, David W; Mieyal, John J; Szweda, Luke I

2003-04-15

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Status epilepticus in the immature rodent brain alters the dynamics of autophagy.  

Science.gov (United States)

There is considerable interest in defining the molecular pathways involved in seizure-induced neuronal death. Necrotic, apoptotic and anti-apoptotic signalling pathways are activated after status epilepticus (SE). Analyses of apoptosis and necrosis have been merely reported, however conditions of autophagic cell death with hallmarks of type 2 programmed cell death-morphology are relatively few. Autophagy is a highly regulated cellular mechanism for the bulk degradation of cytoplasmic contents which is involved in a variety of physiological and pathological conditions associated with neurological diseases. Our goal was to examine whether autophagy is implicated in the cell death machinery after SE. For this purpose, we used lithium-pilocarpine model of SE in 14-day-old rats and examined the dynamics in the expression of autophagic markers in the hippocampus in controls and in animals subjected to SE at 6, 24, and 48h after the insult. Protein levels of central components of the autophagic machinery were dramatically affected by SE with, however, altered dynamics, compared to controls. Levels of LC3, phospho-mTOR/mTOR, BAG3 and Hsp70 were significantly increased, whereas Beclin 1 levels remained unchanged after SE. The dynamics in the expression of Atg3, Atg5, Atg7, Atg14 and LAMP1 were slightly altered. The amount of SQSTM1/p62 underwent a dramatic and highly significant breakdown 48 h after the induction of SE. These results demonstrate for the first time that SE in the immature brain results in significant alterations of autophagy dynamics. There is a growing interest in the role of autophagy in neurodegeneration, and an emerging consensus that autophagy represents a double-edged sword, acting either as a prosurvival mechanism, or as part of a cell death pathway. PMID:24597603

Benz, Alexander Philipp; Niquet, Jerôme; Wasterlain, Claude Guy; Rami, Abdelhaq

2014-05-01

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Kinship alters the effects of forced cohabitation on body weight, mate choice and fitness in the rat-like hamster Tscheskia triton  

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Full Text Available It has been documented that social isolation imparts deleterious effects on gregarious rodents species, but caging in group imparts such effects on solitary rodents. This study was attempted at examining how kinship to affect body weight, behavioral interaction, mate choice and fitness when we caged male and female rat-like hamsters Tscheskia triton in pair, a solitary species. We found that females paired with nonsibling males became heavier than the females paired with sibling males, but both agonistic and amicable behavior between paired males and females did not differ between sibling and nonsibling groups. This indicated that kinship might reduce females’ obesity in response to forced cohabitation, and dissociation might exist between physiological and behavioral responses. Furthermore, binary choice tests revealed that social familiarity between either siblings or nonsiblings decreased their investigating time spent in opposite sex conspecific of cage mates and/or their scents as compared with those of non-mates, suggesting effects of social association on mate and kin selection of the hamsters. On the other side, both females and males caged in pair with siblings show a preference between unfamiliar siblings or their scents and the counterparts of nonsiblings after two month separation, indicating that the kin recognition of the hamsters might also rely on phenotype matching. In addition, cohabitation (or permanent presence of fathers elicited a lower survival of pups in nonsibling pairs than sibling pairs, but did not affect litter size, suggesting that kinship affects fitness when housing male and female ratlike hamsters together. Therefore, inbreeding might be adapted for rare and endangered animals [Current Zoology 55(1: 41–47, 2009].

Lin CONG

2009-02-01

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Mating type and sporulation in yeast. II. Meiosis, recombination, and radiation sensitivity in an alpha-alpha diploid with altered sporulation control.  

Science.gov (United States)

In wild-type S. cerevisiae, diploid cells must be heterozygous at the mating-type locus in order to sporulate. In the preceding paper, we described a number of mutants (CSP mutants), isolated from nonsporulating aa and alpha-alpha parent strains, in which sporulation appeared to be uncoupled from control by mating type. The characterization of one of these mutants (CSP1) is now extended to other processes controlled by mating type. This mutant is indistinguishable from alpha-alpha cells and unlike aalpha cells for mating factor production and response, zygote formation, intragenic mitotic recombination, and for X-ray sensitivity. The mutant apparently undergoes a full round of DNA synthesis in sporulation medium, but with delayed kinetics. Only 20% of the cells complete sporulation. Among spores in completed asci, the frequency of both intra- and intergenic recombination is the same as it is for spores produced by aalpha cells. However, experiments in which cells were shifted from sporulation medium back to minimal growth medium gave a frequency of meiotic recombination between ade2 or leu2 heteroalleles only 25% to 29% as high for CSP1 alpha-alpha diploid or CSP1 aa disomic cells as for aalpha diploid or disomic cells. Because the latter result, indicating recombination defectiveness, measured recombinant production in the entire cell population, whereas the result indicating normal recombination sampled only completed spores, we infer that all meiotic recombination events occuring in the population of CSP1 alpha-alpha cells are concentrated in those few cells which complete sporulation. This high degree of correlation between meiotic recombination and the completion of meiosis and sporulation suggests that recombination may be required for proper meiotic chromosome segregation in yeast just as it appears to be in maize and in Drosophila. PMID:1093937

Hopper, A K; Kirsch, J; Hall, B D

1975-05-01

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Cypermethrin alters the status of oxidative stress in the peripheral blood: relevance to Parkinsonism.  

Science.gov (United States)

Parkinson's disease (PD) is a motor scarcity disorder characterized by the striatal dopamine deficiency owing to the selective degeneration of the nigrostriatal dopaminergic neurons. While oxidative stress is implicated in PD, prolonged exposure to moderate dose of cypermethrin induces Parkinsonism. The study aimed to investigate the status of oxidative stress indicators and antioxidant defence system of the polymorphonuclear leukocytes (PMNs), platelets and plasma to delineate the effect of Parkinsonian dose of cypermethrin in the peripheral blood of rats and its subsequent relevance to Parkinsonism. Nitrite content, lipid peroxidation (LPO) and activity of superoxide dismutase (SOD), catalase, glutathione reductase (GR) and glutathione-S-transferase (GST) were measured in the PMNs, platelets and plasma of control and cypermethrin-treated rats in the presence or absence of a microglial activation inhibitor, minocycline or a dopamine precursor containing the peripheral 3,4-dihydroxyphenylalanine decarboxylase inhibitor, named syndopa, employing the standard procedures. The striatal dopamine was measured to assess the degree of neurodegeneration/neuroprotection. Cypermethrin increased nitrite and LPO in the plasma, platelets and PMNs while it reduced the striatal dopamine content. Catalase and GST activity were increased in the PMNs and platelets; however, it was reduced in the plasma. Conversely, SOD and GR activities were reduced in the PMNs and platelets but increased in the plasma. Minocycline or syndopa reduced the cypermethrin-mediated changes towards normalcy. The results demonstrate that cypermethrin alters the status of oxidative stress indicators and impairs antioxidant defence system of the peripheral blood, which could be effectively salvaged by minocycline or syndopa. The results could be of value for predicting the nigrostriatal toxicity relevant to Parkinsonism. PMID:25270427

Tripathi, Pratibha; Singh, Ashish; Agrawal, Sonal; Prakash, Om; Singh, Mahendra Pratap

2014-12-01

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Mating behaviour and female mate choice in the Harvest mouse (Micromys minutus)  

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The harvest mouse (Micromys minutus) is Britain’s smallest rodent, and one of its least?studied mammals. Mounting concerns over the status of its British populations highlights the paucity of information about this species, not least about different aspects of its behaviour. I study the mating behaviour of the harvest mouse, focusing on female mate choice, and specifically on the effect familiarity with the male has on the female’s mating preference.In ...

Brandt, Ruth; Macdonald, David W.

2010-01-01

 
 
 
 
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Uncoupling the links between male mating tactics and female attractiveness.  

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Because not all females are equally attractive, and because mating reduces the chances of getting further copulations, males should prefer better-quality mates. In this paper, we use the Trinidadian guppy (Poecilia reticulata) to explore the effects of two non-correlated measures of female quality--size and reproductive status--on male mating decisions. All male guppies employ two alternative mating tactics. We found that large females, particularly those from a high predation site, were the ...

Ojanguren, Alfredo F.; Magurran, Anne E.

2004-01-01

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Cell-to-cell communication and cellular environment alter the somatostatin status of delta cells  

International Nuclear Information System (INIS)

Research highlights: ? TGP52 cells display enhanced functionality in pseudoislet form. ? Somatostatin content was reduced, but secretion increased in high glucose conditions. ? Cellular interactions and environment alter the somatostatin status of TGP52 cells. -- Abstract: Introduction: Somatostatin, released from pancreatic delta cells, is a potent paracrine inhibitor of insulin and glucagon secretion. Islet cellular interactions and glucose homeostasis are essential to maintain normal patterns of insulin secretion. However, the importance of cell-to-cell communication and cellular environment in the regulation of somatostatin release remains unclear. Methods: This study employed the somatostatin-secreting TGP52 cell line maintained in DMEM:F12 (17.5 mM glucose) or DMEM (25 mM glucose) culture media. The effect of pseudoislet formation and culture medium on somatostatin content and release in response to a variety of stimuli was measured by somatostatin EIA. In addition, the effect of pseudoislet formation on cellular viability (MTT and LDH assays) and proliferation (BrdU ELISA) was determined. Results: TGP52 cells readily formed pseudoislets and showed enhanced functionality in three-dimensional form with increased E-cadherin expression irrespective of the culture environment used. However, culture in DMEM decreased cellular somatostatin content (P < 0.01) and increased somatostatin secretion in response to a variety of stimuli including arginine, calcium and PMA (P < 0.001) when compared with cells grown in DMEM:F12. Configuration of TGP52 cells as pseudoislets reduced the proliferative rate and increased cellular cytotoxicity irrespective of culture medium used. Conclusions: Somatostatin secretion is greatly facilitated by cell-to-cell interactions and E-cadherin expression. Cellular environment and extracellular glucose also significantly influence the function of delta cells.

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Cell-to-cell communication and cellular environment alter the somatostatin status of delta cells  

Energy Technology Data Exchange (ETDEWEB)

Research highlights: {yields} TGP52 cells display enhanced functionality in pseudoislet form. {yields} Somatostatin content was reduced, but secretion increased in high glucose conditions. {yields} Cellular interactions and environment alter the somatostatin status of TGP52 cells. -- Abstract: Introduction: Somatostatin, released from pancreatic delta cells, is a potent paracrine inhibitor of insulin and glucagon secretion. Islet cellular interactions and glucose homeostasis are essential to maintain normal patterns of insulin secretion. However, the importance of cell-to-cell communication and cellular environment in the regulation of somatostatin release remains unclear. Methods: This study employed the somatostatin-secreting TGP52 cell line maintained in DMEM:F12 (17.5 mM glucose) or DMEM (25 mM glucose) culture media. The effect of pseudoislet formation and culture medium on somatostatin content and release in response to a variety of stimuli was measured by somatostatin EIA. In addition, the effect of pseudoislet formation on cellular viability (MTT and LDH assays) and proliferation (BrdU ELISA) was determined. Results: TGP52 cells readily formed pseudoislets and showed enhanced functionality in three-dimensional form with increased E-cadherin expression irrespective of the culture environment used. However, culture in DMEM decreased cellular somatostatin content (P < 0.01) and increased somatostatin secretion in response to a variety of stimuli including arginine, calcium and PMA (P < 0.001) when compared with cells grown in DMEM:F12. Configuration of TGP52 cells as pseudoislets reduced the proliferative rate and increased cellular cytotoxicity irrespective of culture medium used. Conclusions: Somatostatin secretion is greatly facilitated by cell-to-cell interactions and E-cadherin expression. Cellular environment and extracellular glucose also significantly influence the function of delta cells.

Kelly, Catriona, E-mail: catriona.kelly@qub.ac.uk [SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine (United Kingdom); Flatt, Peter R.; McClenaghan, Neville H. [SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine (United Kingdom)

2010-08-20

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The Memory Alteration Test Discriminates between Cognitively Healthy Status, Mild Cognitive Impairment and Alzheimer's Disease  

Science.gov (United States)

Background/Aims Dementia is a worldwide public health problem and there are several diagnostic tools for its assessment. The aim of this study was to evaluate the performance of the Memory Alteration Test (M@T) to discriminate between patients with early Alzheimer's disease (AD), patients with amnestic mild cognitive impairment (a-MCI), and subjects with a cognitively healthy status (CHS). Methods The discriminative validity was assessed in a sample of 90 patients with AD, 45 patients with a-MCI, and 180 subjects with CHS. Clinical, functional, and cognitive studies were independently performed in a blinded fashion and the gold standard diagnosis was established by consensus on the basis of these results. The test performance was assessed by means of a receiver operating characteristic curve analysis as area under the curve (AUC). Results M@T mean scores were 17.7 (SD = 5.7) in AD, 30.8 (SD = 2.3) in a-MCI, and 44.5 (SD = 3.1) in CHS. A cutoff score of 37 points had a sensitivity of 98.3% and a specificity of 97.8% to differentiate a-MCI from CHS (AUC = 0.999). A cutoff score of 27 points had a sensitivity of 100% and a specificity of 98.9% to differentiate mild AD from a-MCI and from CHS (AUC = 1.000). Conclusions The M@T had a high performance in the discrimination between early AD, a-MCI and CHS. PMID:25298775

Custodio, Nilton; Lira, David; Herrera-Perez, Eder; Nunez del Prado, Liza; Parodi, Jose; Guevara-Silva, Erik; Castro-Suarez, Sheila; Montesinos, Rosa; Cortijo, Patricia

2014-01-01

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A patient with altered mental status and possible seizure reveals an atypical aortic dissection upon workup.  

Science.gov (United States)

Aortic dissection occurs when a tear occurs in the inner muscle wall lining of the aorta, allowing blood to split the muscle layers of the aortic wall apart. It is classically characterized by pain that starts in the upper chest, which then radiates to the upper back and is tearing or ripping in quality. Our objective is to present a case followed by a brief literature review of aortic dissection and uncommon but important features that may be demonstrated. In this report, we present the case of a 57-year-old woman who was transported to the emergency department with an acute episode of altered mental status, presenting as a possible stroke with possible seizures. The patient's only complaint was mild low back pain. Physical examination revealed disorientation to time with no other neurologic deficits or abnormal findings. Results from initial noncontrast head computed tomography, chest radiograph, and laboratory studies were all normal, except for an elevated D-dimer and serum creatinine. Chest computed tomography with contrast demonstrated a type A aortic dissection. The patient was taken emergently to the operating room where the aortic valve and a portion of the ascending aorta were replaced. The patient did well and was discharged from the hospital 5 days later without any permanent sequalae. Aortic dissection is both rare and life threatening and may present with atypical signs. It is important to note that patients may show no signs of typical features or may even display other symptoms based on other branches from the aorta that have been occluded. PMID:24360026

Lawal, Olufolahan J; Dhindsa, Harinder S; Loyd, Joshua W

2014-05-01

46

Facultative mate choice drives adaptive hybridization.  

Science.gov (United States)

Mating with another species (hybridization) is often maladaptive. Consequently, females typically avoid heterospecifics as mates. Contrary to these expectations, female spadefoot toads were more likely to choose heterospecific males when exposed to environmental conditions that favor hybridization. Indeed, those females with phenotypic characteristics for which hybridization is most favorable were most likely to switch from choosing conspecifics to heterospecifics. Moreover, environmentally dependent mate choice has evolved only in populations and species that risk engaging in, and can potentially benefit from, hybridization. Thus, when the benefits of mate choice vary, females may radically alter their mate selection in response to their own phenotype and their environment, even to the point of choosing males of other species. PMID:17991861

Pfennig, Karin S

2007-11-01

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Selenium toxicity but not deficient or super-nutritional selenium status vastly alters the transcriptome in rodents  

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Full Text Available Abstract Background Protein and mRNA levels for several selenoproteins, such as glutathione peroxidase-1 (Gpx1, are down-regulated dramatically by selenium (Se deficiency. These levels in rats increase sigmoidally with increasing dietary Se and reach defined plateaus at the Se requirement, making them sensitive biomarkers for Se deficiency. These levels, however, do not further increase with super-nutritional or toxic Se status, making them ineffective for detection of high Se status. Biomarkers for high Se status are needed as super-nutritional Se intakes are associated with beneficial as well as adverse health outcomes. To characterize Se regulation of the transcriptome, we conducted 3 microarray experiments in weanling mice and rats fed Se-deficient diets supplemented with up to 5 ?g Se/g diet. Results There was no effect of Se status on growth of mice fed 0 to 0.2 ?g Se/g diet or rats fed 0 to 2 ?g Se/g diet, but rats fed 5 ?g Se/g diet showed a 23% decrease in growth and elevated plasma alanine aminotransferase activity, indicating Se toxicity. Rats fed 5 ?g Se/g diet had significantly altered expression of 1193 liver transcripts, whereas mice or rats fed ? 2 ?g Se/g diet had Conclusion This study shows that Se toxicity (5 ?g Se/g diet in rats vastly alters the liver transcriptome whereas Se-deficiency or high but non-toxic Se intake elicits relatively few changes. This is the first evidence that a vastly expanded number of transcriptional changes itself can be a biomarker of Se toxicity, and that identified transcripts can be used to develop molecular biomarker panels that accurately predict super-nutritional and toxic Se status.

Sunde Roger A

2011-01-01

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Mating-induced reduction in accessory reproductive organ size in the stalk-eyed fly Cyrtodiopsis dalmanni  

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Full Text Available Abstract Background Internal reproductive organ size is an important determinant of male reproductive success. While the response of testis length to variation in the intensity of sperm competition is well documented across many taxa, few studies address the importance of testis size in determining other components of male reproductive success (such as mating frequency or the significance of size variation in accessory reproductive organs. Accessory gland length, but not testis length, is both phenotypically and genetically correlated with male mating frequency in the stalk-eyed fly Cyrtodiopsis dalmanni. Here we directly manipulate male mating status to investigate the effect of copulation on the size of both the testes and the accessory glands of C. dalmanni. Results Accessory gland length was positively correlated with male mating frequency. Copulation induced a significant decrease in accessory gland size. The size of the accessory glands then recovered slowly over the next 8–48 hours. Neither testis length nor testis area was altered by copulation. Conclusion These results reveal that the time course of accessory gland recovery corresponds to field observations of mating behaviour and suggest that accessory gland size may limit male mating frequency in C. dalmanni.

Fowler Kevin

2005-06-01

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Altered Antioxidant Status and Increased Lipid Per-Oxidation in Seminal Plasma of Tunisian Infertile Men  

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Human seminal plasma is a natural reservoir of antioxidants that protect spermatozoa from oxidative damages. There is evidence in literature supports the fact that impairments in seminal antioxidant and lipid per-oxidation status play important roles in the physiopathology of male infertility. Our present study forms the first one which was carried out in Tunisia. We evaluated the antioxidant status in the seminal plasma of 120 infertile men programmed to In Vitro Fertilization (IVF) for t...

Fatma Atig, Monia Raffa

2012-01-01

50

Male mating biology  

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Abstract Before sterile mass-reared mosquitoes are released in an attempt to control local populations, many facets of male mating biology need to be elucidated. Large knowledge gaps exist in how both sexes meet in space and time, the correlation of male size and mating success and in which arenas matings are successful. Previous failures in mosquito sterile insect technique (SIT) projects have been linked to poor knowledge of local mating behaviours or the selection of deleterious ...

Howell Paul I; Gj, Knols Bart

2009-01-01

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Casanovas are liars: behavioral syndromes, sperm competition risk, and the evolution of deceptive male mating behavior in live-bearing fishes [v2; ref status: indexed, http://f1000r.es/1ko  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Male reproductive biology can by characterized through competition over mates as well as mate choice. Multiple mating and male mate choice copying, especially in internally fertilizing species, set the stage for increased sperm competition, i.e., sperm of two or more males can compete for fertilization of the female’s ova. In the internally fertilizing fish Poecilia mexicana, males respond to the presence of rivals with reduced expression of mating preferences (audience effect), thereby low...

Bierbach, David; Makowicz, Amber M.; Schlupp, Ingo; Geupel, Holger; Streit, Bruno; Plath, Martin

2013-01-01

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Sudden altered mental state in the elderly: nonconvulsive status epilepticus and the role of the Emergency Department  

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Full Text Available In the elderly, new onset of epilepsy is often associated with vague complaints such as confusion, altered mental status, or memory problems. The absence of clinically apparent convulsions in association with an electroencephalogram showing continuous or recurrent seizure activity has been called nonconvulsive status epilepticus (NCSE. The purpose of this article is to describe the clinical and electroencephalographic features of NCSE in older adults. NCSE is an important, under-recognised and reversible cause of acute prolonged confusion. Although attempts have been made to define and classify this disorder, there is no universally accepted definition or classification yet that encompasses all subtypes or electroclinical scenarios. A urgent electroencephalogram is considered as the method of choice in the diagnostic evaluation of NCSE. Further researches are needed to better define NCSE.

Rocco Galimi

2013-01-01

53

Serum phospholipid monounsaturated fatty acid composition and ?-9-desaturase activity are associated with early alteration of fasting glycemic status.  

Science.gov (United States)

Because alterations in blood fatty acid (FA) composition by dietary lipids are associated with insulin resistance and related metabolic disorders, we hypothesized that serum phospholipid FA composition would reflect the early alteration of fasting glycemic status, even in people without metabolic syndrome (MetS). To examine this hypothesis, serum phospholipid FA, desaturase activities, fasting glycemic status, and cardiometabolic parameters were measured in study participants (n = 1022; 30-69 years; male, n = 527; female, n = 495; nondiabetics without disease) who were stratified into normal fasting glucose (NFG) and impaired fasting glucose (IFG) groups. Total monounsaturated FA (MUFA), oleic acid (OA; 18:1n-9), dihomo-?-linolenic acid (DGLA; 20:3n-6), ?-9-desaturase activity (D9D; 18:1n-9/18:0), and DGLA/linoleic acid (20:3n-6/18:2n-6) in serum phospholipids were significantly higher in IFG subjects than NFG controls. Study subjects were subdivided into 4 groups, based on fasting glucose levels and MetS status. Palmitoleic acid (16:1n-7) was highest in IFG-MetS and lowest in NFG-non-MetS subjects. Oleic acid and D9D were higher in IFG-MetS than in the other 3 groups. Dihomo-?-linolenic acid and DGLA/linoleic acid were higher in MetS than in non-MetS, regardless of fasting glucose levels. The high-sensitivity C-reactive proteins (hs-CRPs) and 8-epi-prostaglandin-F2? were higher in IFG than in NFG, regardless of MetS status. Oxidized low-density lipoproteins were higher in IFG-MetS than in the other 3 groups. Total MUFAs, OA, and D9D were positively correlated with homeostasis model assessment of insulin resistance, fasting glucose, triglyceride, hs-CRP, and 8-epi-prostaglandin-F2?. Palmitoleic acid was positively correlated with triglyceride and hs-CRP. Lastly, total MUFA, OA, palmitoleic acid, and D9D were associated with early alteration of fasting glycemic status, therefore suggesting that these may be useful markers for predicting the risk of type 2 diabetes and cardiometabolic diseases. PMID:25236425

Cho, Jae Sun; Baek, Seung Han; Kim, Ji Young; Lee, Jong Ho; Kim, Oh Yoen

2014-09-01

54

The influence of nonrandom mating on population growth.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

When nonrandom mating alters offspring numbers or the distribution of offspring phenotypes, it has the potential to impact the population growth rate. Similarly, sex-specific demographic parameters that influence the availability of mating partners can leave a signature on the population growth rate. We develop a general framework to explore how mating patterns and sex differences influence the population growth rate. We do this by constructing a two-sex integral projection model to explore w...

Schindler, S.; Neuhaus, P.; Gaillard, Jm; Coulson, T.

2013-01-01

55

Altered mental status, an unusual manifestation of early disseminated Lyme disease: A case report  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Early disseminated Lyme disease can have a myriad of central nervous system manifestations. These run the gamut from meningitis to radiculopathy and cranial neuropathy. Here we present a case that manifested with only acute mental status change in the setting of central nervous system involvement with Lyme disease. A paucity of other central nervous system manifestations is rare, especially with positive serum and cerebrospinal fluid markers. This article underscores the im...

Chabria Shiven B; Lawrason Jock

2007-01-01

56

Parental investment, mate choice, and mate quality.  

Science.gov (United States)

Current theory in sexual selection is extended to predict within-sex variability with regard to selectivity towards mates in different mating systems. Generally, the sex that invests more in the care of each offspring should be more selective of mates than the sex investing less. Within each sex, individuals of low male quality should be less selective than individuals of high quality, but there should be less variation in selectivity among individuals of the sex investing more. When only one sex contributes parental care, however, individuals of that sex should be uniformly selective, while the other sex is expected to mate indiscriminately. Using feral pigeons (Columba livia), these hypotheses are tested for the case in which both sexes contribute substantial parental care, but in which females contribute more than males. As predicted, females were found to be more selective of mates than males were. On certain criteria, males of lower quality were less selective of mates than males of higher quality. PMID:269407

Burley, N

1977-08-01

57

Regulation of hypoxia inducible factor-1? expression by the alteration of redox status in HepG2 cells  

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Full Text Available Abstract Hypoxia inducible factor-1 (HIF-1 has been considered as a critical transcriptional factor in response to hypoxia. It can increase P-glycoprotein (P-Gp thus generating the resistant effect to chemotherapy. At present, the mechanism regulating HIF-1? is still not fully clear in hypoxic tumor cells. Intracellular redox status is closely correlated with hypoxic micro-environment, so we investigate whether alterations in the cellular redox status lead to the changes of HIF-1? expression. HepG2 cells were exposed to Buthionine sulphoximine (BSO for 12 h prior to hypoxia treatment. The level of HIF-1? expression was measured by Western blot and immunocytochemistry assays. Reduce glutathione (GSH concentrations in hypoxic cells were determined using glutathione reductase/5,5'-dithiobis-(2-nitrob-enzoic acid (DTNB recycling assay. To further confirm the effect of intracellular redox status on HIF-1? expression, N-acetylcysteine (NAC was added to culture cells for 8 h before the hypoxia treatment. The levels of multidrug resistance gene-1 (MDR-1 and erythropoietin (EPO mRNA targeted by HIF-1? in hypoxic cells were further determined with RT-PCR, and then the expression of P-Gp protein was observed by Western blotting. The results showed that BSO pretreatment down-regulated HIF-1? and the effect was concentration-dependent, on the other hand, the increases of intracellular GSH contents by NAC could partly elevate the levels of HIF-1? expression. The levels of P-Gp (MDR-1 and EPO were concomitant with the trend of HIF-1? expression. Therefore, our data indicate that the changes of redox status in hypoxic cells may regulate HIF-1? expression and provide valuable information on tumor chemotherapy.

Zhang Wu-kui

2011-05-01

58

Zinc supplementation alters plasma aluminum and selenium status of patients undergoing dialysis: a pilot study.  

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End stage renal disease patients undergoing long-term dialysis are at risk for abnormal concentrations of certain essential and non-essential trace metals and high oxidative stress. We evaluated the effects of zinc (Zn) supplementation on plasma aluminum (Al) and selenium (Se) concentrations and oxidative stress in chronic dialysis patients. Zn-deficient patients receiving continuous ambulatory peritoneal dialysis or hemodialysis were divided into two groups according to plasma Al concentrations (HA group, Al > 50 g/L; and MA group, Al > 30 to ? 50 g/L). All patients received daily oral Zn supplements for two months. Age- and gender-matched healthy individuals did not receive Zn supplement. Clinical variables were assessed before, at one month, and after the supplementation period. Compared with healthy subjects, patients had significantly lower baseline plasma Se concentrations and higher oxidative stress status. After two-month Zn treatment, these patients had higher plasma Zn and Se concentrations, reduced plasma Al concentrations and oxidative stress. Furthermore, increased plasma Zn concentrations were related to the concentrations of Al, Se, oxidative product malondialdehyde (MDA), and antioxidant enzyme superoxide dismutase activities. In conclusion, Zn supplementation ameliorates abnormally high plasma Al concentrations and oxidative stress and improves Se status in long-term dialysis patients. PMID:23609777

Guo, Chih-Hung; Chen, Pei-Chung; Hsu, Guoo-Shyng W; Wang, Chia-Liang

2013-04-01

59

Zinc Supplementation Alters Plasma Aluminum and Selenium Status of Patients Undergoing Dialysis: A Pilot Study  

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Full Text Available End stage renal disease patients undergoing long-term dialysis are at risk for abnormal concentrations of certain essential and non-essential trace metals and high oxidative stress. We evaluated the effects of zinc (Zn supplementation on plasma aluminum (Al and selenium (Se concentrations and oxidative stress in chronic dialysis patients. Zn-deficient patients receiving continuous ambulatory peritoneal dialysis or hemodialysis were divided into two groups according to plasma Al concentrations (HA group, Al > 50 ?g/L; and MA group, Al > 30 to ? 50 ?g/L. All patients received daily oral Zn supplements for two months. Age- and gender-matched healthy individuals did not receive Zn supplement. Clinical variables were assessed before, at one month, and after the supplementation period. Compared with healthy subjects, patients had significantly lower baseline plasma Se concentrations and higher oxidative stress status. After two-month Zn treatment, these patients had higher plasma Zn and Se concentrations, reduced plasma Al concentrations and oxidative stress. Furthermore, increased plasma Zn concentrations were related to the concentrations of Al, Se, oxidative product malondialdehyde (MDA, and antioxidant enzyme superoxide dismutase activities. In conclusion, Zn supplementation ameliorates abnormally high plasma Al concentrations and oxidative stress and improves Se status in long-term dialysis patients.

Chia-Liang Wang

2013-04-01

60

Ethanol Intake during Lactation Alters Milk Nutrient Composition and Growth and Mineral Status of Rat Pups  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in english Lactating Wistar rats were fed a liquid diet containing either ethanol [ethanol-fed group (EFG)] or an isocaloric amount of carbohydrate [pair-fed group (PFG)] from day 1 postpartum up to day 14 of lactation, to investigate micro/macronutrient milk composition and the mineral status of pups. EFG pre [...] sented a reduction of daily milk production and milk composition was significantly higher in protein and lower in carbohydrate, while the lipid content was similar to that of PFG. When compared to PFG, the milk of EFG had a decreased proportion of C22:6 n-3 fatty acid and an increase in medium-chain fatty acids and of several minerals. Pups of EFG showed reduced growth and a lower concentration of Cu and Sr in plasma and lower concentrations of Ca, P and Cl, and higher concentrations of Cd in the brain. We conclude that maternal EtOH intake greatly impairs lactational performance and modifies the mineral status of pups.

CÍNTIA R.P, AZARA; INGRID C, MAIA; CAROLINA N, RANGEL; MÁRIO A.C, SILVA-NETO; RENATA F.B, SERPA; EDGAR F.O, DE JESUS; MARIA G, TAVARES  DO CARMO; ELIANE, FIALHO.

 
 
 
 
61

Altered Antioxidant Status and Increased Lipid Per-Oxidation in Seminal Plasma of Tunisian Infertile Men  

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Full Text Available Human seminal plasma is a natural reservoir of antioxidants that protect spermatozoa from oxidative damages. There is evidence in literature supports the fact that impairments in seminal antioxidant and lipid per-oxidation status play important roles in the physiopathology of male infertility. Our present study forms the first one which was carried out in Tunisia. We evaluated the antioxidant status in the seminal plasma of 120 infertile men programmed to In Vitro Fertilization (IVF for the first tentative. Patients were characterized by an idiopathic infertility. They were divided into three groups: normozoospermics who were considered as controls (n=40, asthenozoospermics (Astheno; n=45 and oligoasthenoteratozoospermics (OAT; n=35. Seminal activities of superoxide dismutase (SOD and glutathione peroxidase (GPX and the levels of glutathione (GSH, zinc (Zn and malondialdehyde (MDA were measured. With the significant increase of the seminal activities of SOD and GPX in normozoospermics group, there were positive correlations observed between this enzymes and sperm quality. Also, significant elevated rates of seminal zinc and GSH were observed in control group, but there was contradictory associations reflecting the effects of these antioxidants on semen parameters. However, we noted significant increase of MDA levels in groups with abnormal seminogram. We showed negative associations between this per-oxidative marker and sperm parameters. These results obviously suggested that impairment on seminal antioxidants is an important risk factor for low sperm quality associated to idiopathic infertility and as a result can lead to poor IVF outcome.

Fatma Atig, Monia Raffa, Habib Ben Ali, Kerkeni Abdelhamid, Ali Saad, Mounir Ajina

2012-01-01

62

Mate Selection among Married and Cohabiting Couples.  

Science.gov (United States)

Examines comparative patterns of educational and racial assortative mating or homogany among married and cohabiting couples, and evaluates whether women and men trade in socioeconomic status and racial caste prestige. Lists several findings, including married/cohabiting couples are highly homogenous with respect to race and education. Suggests…

Blackwell, Debra L.; Lichter, Daniel T.

2000-01-01

63

MicroRNA expression profiles are altered by gonadotropins and vitamin C status during in vitro follicular growth.  

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MicroRNAs (miRs) are known to repress target genes at posttranscriptional level and play important roles in the maturation of cells. However, the expression profiles of miRs during follicular maturation have not been fully elucidated. This study was designed to investigate the expression profiles of miRs in murine follicles according to human chorionic gonadotropin (hCG) treatment and vitamin C status during in vitro culture. Ovaries were removed from the 12-day-old wild-type and vitamin C-deficient (L-gulonogammalactone oxidase knockout, Gulo-/-) C57BL6 mice. Preantral follicles were isolated and cultured in 20 µL droplets of culture media supplemented with follicle-stimulating hormone and luteinizing hormone (FSH + LH). After their full maturation, follicles were divided into 2 groups: with and without hCG treatment. Real-time polymerase chain reaction (PCR) was performed using oocytes and granulosa cells (G-cells) to evaluate the miRs known to be expressed mainly in the mouse ovary. After the addition of hCG, miR profiles showed divergent changes between oocytes and G-cells. These profiles significantly differed from those of hCG(-) group. Compared to wild type, Gulo-/- mice showed altered miR profiles in matured oocytes and G-cells. Conclusively, hCG supplementation and vitamin C status alter the miR expression profiles in oocytes and G-cells during in vitro growth of murine follicles. PMID:20861395

Kim, Yong Jin; Ku, Seung Yup; Rosenwaks, Zev; Liu, Hung Ching; Chi, Sung Wook; Kang, Jae Seung; Lee, Wang Jae; Jung, Kyung Chun; Kim, Seok Hyun; Choi, Young Min; Kim, Jung Gu; Moon, Shin Yong

2010-12-01

64

Mate Selection Preferences among African American College Students.  

Science.gov (United States)

Examines the attitudes and preferences of African American college students toward physical characteristics, social status, and related variables regarding dating and future mate selection. Findings mostly confirmed that females would differ from males on social status variables (willing to date persons from lower social status), and males would…

Ross, Louie E.

1997-01-01

65

Altered antioxidant-oxidant status in the aqueous humor and peripheral blood of patients with retinitis pigmentosa.  

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Retinitis Pigmentosa is a common form of hereditary retinal degeneration constituting the largest Mendelian genetic cause of blindness in the developed world. It has been widely suggested that oxidative stress possibly contributes to its pathogenesis. We measured the levels of total antioxidant capacity, free nitrotyrosine, thiobarbituric acid reactive substances (TBARS) formation, extracellular superoxide dismutase (SOD3) activity, protein, metabolites of the nitric oxide/cyclic GMP pathway, heme oxygenase-I and inducible nitric oxide synthase expression in aqueous humor or/and peripheral blood from fifty-six patients with retinitis pigmentosa and sixty subjects without systemic or ocular oxidative stress-related disease. Multivariate analysis of covariance revealed that retinitis pigmentosa alters ocular antioxidant defence machinery and the redox status in blood. Patients with retinitis pigmentosa present low total antioxidant capacity including reduced SOD3 activity and protein concentration in aqueous humor. Patients also show reduced SOD3 activity, increased TBARS formation and upregulation of the nitric oxide/cyclic GMP pathway in peripheral blood. Together these findings confirmed the hypothesis that patients with retinitis pigmentosa present reduced ocular antioxidant status. Moreover, these patients show changes in some oxidative-nitrosative markers in the peripheral blood. Further studies are needed to clarify the relationship between these peripheral markers and retinitis pigmentosa. PMID:24069283

Martínez-Fernández de la Cámara, Cristina; Salom, David; Sequedo, Ma Dolores; Hervás, David; Marín-Lambíes, Cristina; Aller, Elena; Jaijo, Teresa; Díaz-Llopis, Manuel; Millán, José María; Rodrigo, Regina

2013-01-01

66

Altered energy status of primary cerebellar granule neuronal cultures from rats exposed to lead in the pre- and neonatal period.  

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This paper examines the effect of pre- and neonatal exposure of rats to lead (0.1% lead acetate in drinking water, resulting in rat offspring whole blood lead concentration (Pb-B) 4?g/dL) on the energy status of neuronal mitochondria by measuring changes in ATP, ADP, AMP, adenosine, TAN concentration, adenylate energy charge value (AEC) and mitochondrial membrane potential in primary cerebellar granule neurons (CGC) in dissociated cultures. Fluorescence studies were performed to imaging and evaluate mitochondria mass, mitochondrial membrane potential, intracellular and mitochondrial reactive oxygen species (ROS) production. The Na(+)/K(+) ATPase activity in intact CGC was measured spectrophotometrically. Our data shows that pre- and neonatal exposure of rats to Pb, even below the threshold of whole blood Pb value considered safe for people, affects the energy status of cultured primary cerebellar granule neurons through a decrease in ATP and TAN concentrations and AEC value, inhibition of Na(+)/K(+) ATPase, and increase in intracellular and mitochondrial ROS concentration. These observations suggest that even these low levels of Pb are likely to induce important alterations in neuronal function that could play a role in neurodegeneration. PMID:21108985

Baranowska-Bosiacka, I; Gutowska, I; Marchetti, C; Rutkowska, M; Marchlewicz, M; Kolasa, A; Prokopowicz, A; Wiernicki, I; Piotrowska, K; Ba?kiewicz, M; Safranow, K; Wiszniewska, B; Chlubek, D

2011-02-01

67

Alterations in monoamine levels after cocaine-induced status epilepticus and death in striatum and prefrontal cortex of mice.  

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Seizures and death are the more important toxic consequences related to cocaine overdose. Some reports have shown that pharmacological manipulations in dopaminergic, serotonergic and noradrenergic systems alter the occurrence of cocaine-induced convulsions and death. Based on this fact, this work was performed to determine the changes in monoamine levels (DA, 5-HT and NE) and their metabolites (DOPAC, HVA and 5-HIAA) after cocaine-induced status epilepticus (SE) and death in striatum and prefrontal cortex (PFC). The monoamines and their metabolites were assayed by reverse-phase high-performance liquid chromatography with electrochemical detection. Animal SE in striatum presented a decrease in DA and NE levels and an increase in HVA although in PFC there was an increase in DA, 5-HT and NE. Animals that died from cocaine-induced seizures in striatum showed an increase only in NE levels, but on the other hand in PFC a decrease occurred in DA and NE levels. Taken together these results indicated that cocaine-induced SE and death altered monoamine levels in different ways depending on the brain area studied, suggesting that different mechanisms are involved. PMID:15158010

Macêdo, D S; Vasconcelos, S M M; Belchior, L D; Santos, R S; Viana, G S B; Sousa, F C F

2004-05-27

68

A combined chemometric and quantitative NMR analysis of HIV/AIDS serum discloses metabolic alterations associated with disease status.  

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Individuals infected with the human immunodeficiency virus (HIV) often suffer from concomitant metabolic complications. Treatment with antiretroviral therapy has also been shown to alter the metabolism of patients. Although chemometric analysis of nuclear magnetic resonance (NMR) spectra of human sera can distinguish normal sera (HIVneg) from HIV-infected sera (HIVpos) and sera from HIV-infected patients on antiretroviral therapy (ART), quantitative analysis of the discriminating metabolites and their relationship to disease status has yet to be determined. The objectives of the study were to analyze NMR spectra of HIVneg, HIVpos, and ART serum samples with a combination of chemometric and quantitative methods and to compare the NMR data with disease status as measured by viral load and CD4 count. High-resolution magic angle spinning (HRMAS) NMR spectroscopy was performed on HIVneg (N = 10), HIVpos (N = 10), and ART (N = 10) serum samples. Chemometric linear discriminant analysis classified the three groups of spectra with 100% accuracy. Concentrations of 12 metabolites were determined with a semi-parametric metabolite quantification method named high-resolution quantum estimation (HR-QUEST). CD4 count was directly associated with alanine (p = 0.008), and inversely correlated with both glutamine (p = 0.017) and glucose (p = 0.022) concentrations. A multivariate linear model using alanine, glutamine and glucose as covariates demonstrated an association with CD4 count (p = 0.038). The combined chemometric and quantitative analysis of the data disclosed previously unknown associations between specific metabolites and disease status. The observed associations with CD4 count are consistent with metabolic disorders that are commonly seen in HIV-infected patients. PMID:25105420

McKnight, Tracy R; Yoshihara, Hikari A I; Sitole, Lungile J; Martin, Jeffery N; Steffens, Francois; Meyer, Debra

2014-09-30

69

Low-impact mating system  

Science.gov (United States)

An androgynous mating system for mating two exoatmospheric space modules comprising a first mating assembly capable of mating with a second mating assembly; a second mating assembly structurally identical to said first mating assembly, said first mating assembly comprising; a load ring; a plurality of load cell subassemblies; a plurality of actuators; a base ring; a tunnel; a closed loop control system; one or more electromagnets; and one or more striker plates, wherein said one or more electomagnets on said second mating assembly are capable of mating with said one or more striker plates on said first mating assembly, and wherein said one or more striker plates is comprised of a plate of predetermined shape and a 5-DOF mechanism capable of maintaining predetermined contact requirements during said mating of said one or more electromagnets and said one or more striker plates.

Lewis, James L. (Inventor); Carroll, Monty B. (Inventor); Le, Thang D. (Inventor); Morales, Ray H. (Inventor); Robertson, Brandan R. (Inventor)

2009-01-01

70

Enhanced cardiovascular risk and altered oxidative status in elders with moderate excessive body fat.  

Science.gov (United States)

Aging and obesity are linked to oxidative stress. Oxidative stress may mediate age-related cardiovascular diseases. Although the body mass index (kg/m2) defines obesity (?30) and overweight (25-29.9), it may fail to detect crucial differences in body fat content in elders. Consequently, we measured body fatness in 42 healthy elders and evaluated their cardiovascular risk factors and the extent of their physical activity. We assessed plasma, erythrocytes, and saliva oxidative stress biomarkers in this population. A higher fat mass was associated with a less active lifestyle, more metabolic syndrome components, an enhanced Framingham 10-year risk score, and augmented insulin resistance. Individuals with excessive body fat had significantly less oral peroxidase enzymes activity than those with normal body fat. Erythrocyte susceptibility to oxidative hemolysis, previously reported to be elevated with physical activity, was marginally lower in the higher fat group. Other biomarkers of oxidative stress in saliva, plasma, and erythrocytes were similar in both groups. A 6% elevation in body fat with a less active lifestyle and an increased cardiovascular risk is associated with a decline in salivary anti-oxidative activity. Such reduced activity may contribute to deteriorating oral health in obese elders. Thus, this study provides novel information on the contribution of excessive body fat to oxidative status and cardiovascular risk in old age. PMID:24617844

Narotzki, Baruch; Reznick, Abraham Z; Mitki, Tali; Aizenbud, Dror; Levy, Yishai

2014-08-01

71

Effects of altered thyroid status on beta-adrenergic actions on skeletal muscle glycogen metabolism.  

Science.gov (United States)

The effects of hypothyroidism on glycogen metabolism in rat skeletal muscle were studied using the perfused rat hindlimb preparation. Three weeks after propylthiouracil treatment, serum thyroxine was undetectable and muscle glycogen and Glc-6-P were decreased. Basal and epinephrine-stimulated phosphorylase a and phosphorylase b kinase activities were also significantly reduced, as were epinephrine-stimulated cAMP accumulation and cAMP-dependent protein kinase activity. Conversely, basal and epinephrine-stimulated glycogen synthase I activities were significantly higher while the Ka of the enzyme for Glc-6-P was lower in hypothyroid animals. Propylthiouracil-treated rats also had increased phosphoprotein phosphatase activities towards phosphorylase and glycogen synthase and decreased activity of phosphatase inhibitor 1. beta-Adrenergic receptor binding and basal and epinephrine-stimulated adenylate cyclase activities were reduced in muscle particulate fractions from hypothyroid rats. Administration of triiodothyronine to rats for 3 days after 3 weeks of propylthiouracil treatment restored the altered metabolic parameters to normal. It is proposed that the decreased beta-adrenergic responsiveness of the enzymes of glycogen metabolism in hypothyroid rat skeletal muscle is due to increased activity of phosphoprotein phosphatases and to reduced beta-adrenergic receptors and adenylate cyclase activity. PMID:2991289

Chu, D T; Shikama, H; Khatra, B S; Exton, J H

1985-08-25

72

Mate choice for a male carotenoid-based ornament is linked to female dietary carotenoid intake and accumulation  

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Full Text Available Abstract Background The coevolution of male traits and female mate preferences has led to the elaboration and diversification of sexually selected traits; however the mechanisms that mediate trait-preference coevolution are largely unknown. Carotenoid acquisition and accumulation are key determinants of the expression of male sexually selected carotenoid-based coloration and a primary mechanism maintaining the honest information content of these signals. Carotenoids also influence female health and reproduction in ways that may alter the costs and benefits of mate choice behaviours and thus provide a potential biochemical link between the expression of male traits and female preferences. To test this hypothesis, we manipulated the dietary carotenoid levels of captive female house finches (Carpodacus mexicanus and assessed their mate choice behavior in response to color-manipulated male finches. Results Females preferred to associate with red males, but carotenoid supplementation did not influence the direction or strength of this preference. Females receiving a low-carotenoid diet were less responsive to males in general, and discrimination among the colorful males was positively linked to female plasma carotenoid levels at the beginning of the study when the diet of all birds was carotenoid-limited. Conclusions Although female preference for red males was not influenced by carotenoid intake, changes in mating responsiveness and discrimination linked to female carotenoid status may alter how this preference is translated into choice. The reddest males, with the most carotenoid rich plumage, tend to pair early in the breeding season. If carotenoid-related variations in female choice behaviour shift the timing of pairing, then they have the potential to promote assortative mating by carotenoid status and drive the evolution of carotenoid-based male plumage coloration.

Toomey Matthew B

2012-01-01

73

Mating behaviour and mating competitiveness of radiation sterilized males of Dysdercus koenigii Fabricius  

International Nuclear Information System (INIS)

In Dysdercus koenigii F., while, the females were ready for mating soon after emergence, the males attained sexual maturity only after 36-48 h. Irradiation of males with a sterilizing dose of 70 Gy of x rays prior to attaining sexual maturity brought about delay in mating. Irradiation after attaining sexual maturity did not however, alter mating behaviour. Evaluation of mating competitiveness of sterile males by confining a normal female with sterile and normal males in 1:1 or 2:1 ratio and then recording the type of matings that occurred revealed that 1) mating competitiveness of males rendered sterile by irradiating prior to attaining maturity was greatly reduced even when the sterile males were aged for 48 hrs 2) when males were irradiated after attaining maturity, they significantly out numbered the normal males in mating with females, apparently indicating their becoming more vigorous than normal males. Irradiation during early 5th instar induced wing deformities. Such males having wing deformities failed to undergo copulation with normal females, but wing deformity among females did not prevent them from undergoing copulation with normal males. (author). 11 refs., 3 tabs

74

The MAT1 Locus of Histoplasma capsulatum Is Responsive in a Mating Type-Specific Manner?  

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Recombination events associated with sexual replication in pathogens may generate new strains with altered virulence. Histoplasma capsulatum is a mating-competent, pathogenic fungus with two described phenotypic mating types, + and ?. The mating (MAT) locus of H. capsulatum was identified to facilitate molecular studies of mating in this organism. Through syntenic analysis of the H. capsulatum genomic sequence databases, a MAT1-1 idiomorph region was identified in H. capsulatum strains G217...

Bubnick, Meggan; Smulian, A. George

2007-01-01

75

Olfactory perception in women with physiologically altered hormonal status (during pregnancy and postmenopause  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction Olfaction is considered to be the ability to: perceive, conduct and recognize scents and odors. With its numerous connections to the limbic system and reticular formation, the olfactory system affects regulation of numerous vegetative functions, visceral functions and sexual behavior. Since estrogen and progesterone protect the olfactory function, changes in their levels in particular physiological states in women (in pregnancy and postmenopause exert an influence on the ability to feel and recognize smells. It has its role in creating emotions and adjustment of visceral and vegetative response to particular emotional states. Also, it represents the connection between higher cortical functions and the endocrine system. Material and methods Our investigation was performed at the Ear, Nose and Throat Clinic in Novi Sad. The research included 80 healthy women classified into 4 groups; 20 women aged between 20 and 30; 20 women in the first trimester of pregnancy aged between 20 and 30; 20 premenopausal women aged between 41 and 50; and 20 women at least 3 years in postmenopause, aged between 41 and 50. For our research we used an olfactometer and the Fortunato-Niccolini method. Results and discussion In pregnancy the thresholds of perception (TP and identification (TI of examined substances were slightly lower in comparison to nonpregnant women of the same ages, but without any statistical significance (p>0.05. In climacteric-postmenopausal women there was a significant decrease of olfactory ability in comparison to nonmenopausal women of the same ages (p<0.01. Conclusion All changes of the olfactory function in pregnancy are explained by mental changes of pregnant women as well as their hormonal status. Significant decrease of olfactory ability in postmenopause is explained by decline in sexual hormone levels.

Savovi? Slobodan N.

2002-01-01

76

Assortative mating: sex differences in mate selection for married and unmarried couples.  

Science.gov (United States)

We studied assortative mating for age, nationality, educational level, and occupational level in married and unmarried parents to test evolutionary models explaining mate selection among humans. We used the marriage and birth registers of the Venezuelan population to compare recently married, fertile married, and fertile unmarried couples. The results show significant assortative mating for all variables, but the results are strongest for age and education. These data suggest that (1) selection criteria based on age vary along the life cycle and differ between married and unmarried couples; (2) male's socioeconomic status is more related to the availability of younger females among unmarried couples compared with married couples, except for young couples; and (3) female selection for better (more educated and/or better employed) mates is stronger among married couples, whereas male selection for younger females or those showing actual reproductive potential is stronger among unmarried couples. PMID:7721273

Jaffe, K; Chacon-Puignau, G

1995-02-01

77

Repeated ethanol exposure during late gestation alters the maturation and innate immune status of the ovine fetal lung.  

Science.gov (United States)

Little is known about the effects of fetal ethanol exposure on lung development. Our aim was to determine the effects of repeated ethanol exposure during late gestation on fetal lung growth, maturation, and inflammatory status. Pregnant ewes were chronically catheterized at 91 days of gestational age (DGA; term approximately 147 days). From 95-133 DGA, ewes were given a 1-h daily infusion of either 0.75 g ethanol/kg (n = 9) or saline (n = 8), with tissue collection at 134 DGA. Fetal lungs were examined for changes in tissue growth, structure, maturation, inflammation, and oxidative stress. Between treatment groups, there were no differences in lung weight, DNA and protein contents, percent proliferating and apoptotic cells, tissue and air-space fractions, alveolar number and mean linear intercept, septal thickness, type-II cell number and elastin content. Ethanol exposure caused a 75% increase in pulmonary collagen I alpha1 mRNA levels (P < 0.05) and a significant increase in collagen deposition. Surfactant protein (SP)-A and SP-B mRNA levels were approximately one third of control levels following ethanol exposure (P < 0.05). The mRNA levels of the proinflammatory cytokines interleukin (IL)-1beta and IL-8 were also lower (P < 0.05) in ethanol-exposed fetuses compared with controls. Pulmonary malondialdehyde levels tended to be increased (P = 0.07) in ethanol-exposed fetuses. Daily exposure of the fetus to ethanol during the last third of gestation alters extracellular matrix deposition and surfactant protein gene expression, which could increase the risk of respiratory distress syndrome after birth. Changes to the innate immune status of the fetus could increase the susceptibility of the neonatal lungs to infection. PMID:19112099

Sozo, Foula; O'Day, Luke; Maritz, Gert; Kenna, Kelly; Stacy, Victoria; Brew, Nadine; Walker, David; Bocking, Alan; Brien, James; Harding, Richard

2009-03-01

78

Matings with laminations  

CERN Document Server

We give a topological description of the space of quadratic rational maps with superattractive two-cycles: its "non-escape locus" M2 (the analog of the Mandelbrot set M) is locally connected, it is the continuous image of M under a canonical map, and it can be described as M (minus the 1/2-limb), mated with the lamination of the basilica. The latter statement is a refined version of a conjecture of Ben Wittner, which in its original version requires local connectivity of M to even be stated. Our methods of mating with a lamination also apply to dynamical matings of certain non-locally connected Julia sets.

Dudko, Dzmitry

2011-01-01

79

ERYTHROCYTE BLOOD GROUP ANTIGENS AND ALTERATIONS OF THE HORMONAL STATUS AMONG THE REPRODUCTIVE AGE WOMEN WITH BREAST TUMORS  

Directory of Open Access Journals (Sweden)

Full Text Available The significance of ABO blood system groups antigens in development of some malignant tumors is already established. The alteration of  hormonal homeostasis must also be taken into account. Hence the aim  of   the investigation was to study ABO  and Rh blood system antigens and hormonal status among  reproductive age  women with benign and malignant breast   tumors. Methods: The determination of  hormones was made by the enzymatic analysis method (ELAIZA, provided by proper ELAIZA kits. For the study of ABO and Rh-Hr system antigens, internationally recognized immunoserology methods were used.Results: High index of  the breast gland tumors  were  revealed  in  patients with A(II phenotypic group,  according to the  ABO  system.  The frequency distribution of O(I phenotypic group was low  among women with breast tumors. Among  D, C, E, c and e antigens of  the Rh system, the frequency of D and E antigens were increased in benign and malignant breast tumors patients. The study of hormonal balance revealed thyroid gland hypofunction and increased level of estradiol on the background of  increased testosterone and decreased progesterone levels. Such hormonal imbalance and  excess  production of estradiol creates conditions for malignant tumor formation in reproductive age women.Conclusion: The highest frequency of breast cancer in reproductive age was revealed in A(II group patients. The wide spectrum of hormonal disorders were revealed in breast tumor patients of the reproductive age, which was especially clear in cases of malignant tumor.

Irina Nakashidze

2014-04-01

80

Mating and immunity in invertebrates.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mating and immunity are intimately linked to fitness. In both vertebrates and invertebrates, recent investigations into mate choice for immunity, tradeoffs between reproduction and immunity, and the relationships between post-mating processes and immune function have revealed that mating and immunity are also intimately linked to each other. Here, we focus on invertebrates and critically examine the evidence that immunity is under sexual selection, both pre- and post-mating, and explore other...

Lawniczak, Mk; Barnes, Ai; Linklater, Jr; Boone, Jm; Wigby, S.; Chapman, T.

2007-01-01

 
 
 
 
81

[Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae) requires long matings for successful reproduction].  

Science.gov (United States)

The occurrence of multiple and long matings seem to play an important role in the reproduction of the predatory stinkbugs such as Podisus nigrispinus (Dallas). However, the mechanisms underlying these behaviors remain unclear. In this study, the reproduction of P. nigrispinus was investigated as function of females' choice for their mating pair based on male body size and previous mating status, risk of predation and duration of mating. The female mating behavior was studied with female having multiple, partial or no partner choice based on male body size. Time to initiate a mating and its duration was observed after pairing males and females under risk of predation imposed by the presence of the predatory wasp Polistes versicolor Oliver. In addition, aiming to determine the reasons for long lasting matings, female had their mating interrupted at different intervals. Our data indicated that P. nigrispinus females do not select male partners as function of their body size and mating status. Duration of mating, mating partners' choice, and female fecundity and fertility were not influenced by the male size and risk of predation imposed by the predatory wasps. Mating interrupted after 30, 60, 120 and 240 min resulted in only 0, 3.1, 7.7 and 34% of egg hatching compared to 74.2% under uninterrupted mating (338 to 671 min long). Therefore, the reproductive success of P. nigrispinus females does not depend on male size and male mating status, but requires long-lasting mating as a condition for adequate spermatozoa transference to females instead. PMID:20098920

Rodrigues, Agna R S; Torres, Jorge B; Siqueira, Herbert A A; Teixeira, Valéria W

2009-01-01

82

Paced mating behavior persists in rats with vaginocervical Lidocaine  

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The present study tested whether the topical application of a local anesthetic (Lidocaine) to the vaginocervical region altered the pattern of paced mating behavior displayed by gonadectomized, hormone-primed female rats. Both rats receiving Lidocaine and rats receiving vehicle exhibited the expected lengthening of contact-return latency as the intensity of the mating stimuli increased (mount < intromission < ejaculation). Although rats given Lidocaine versus vehicle received a greater number...

Meerts, Sarah H.; Boisvert, Eilish M.; Spjut, Kersti A.; Clark, Ann S.

2010-01-01

83

Mate Selection and Mating Behaviour in Spider Crabs  

Science.gov (United States)

Female spider crabs can only mate after the terminal moult, which means that they must either mate whilst soft-shelled after moulting, or subsequently when hard-shelled. There is evidence that some, at least, do both, whereas the majority of crabs mate in only one or other of these states. The mating behaviour, and the means of detecting receptive females, have been studied in a spider crab, Inachus dorsettensis. In this species, mating is predominantly hard-shelled, and receptive females are recognized by their emission of chemical pheromones. The implications of the behaviour patterns for male mating efficiency, sperm competition and female reproductive success are discussed. Mate selection and mating behaviour in other spider crabs are compared with I. dorsettensis. Reasons for similarities and differences are reviewed.

Jones, D. R.; Hartnoll, R. G.

1997-02-01

84

Size, Mates, and Fates  

Science.gov (United States)

This perspective introduces a special section on pathways initiated by three different types of receptors: brassinosteroid receptors that control plant size, G protein-coupled receptors that control mating responses in yeast, and Notch receptors that control cell fate in animals.

Nancy Gough (AAAS;); Elizabeth Adler (AAAS;); L. Bryan Ray (AAAS;)

2006-12-01

85

MATE's ROV Competitions  

Science.gov (United States)

This webpage from the Marine Advanced Technology Education Center (MATE) provides information about the center's ROV competition. The competitions "connect students and educators with employers and working professionals from marine industries, highlight marine-related career opportunities, and promote the development of technical, problem solving, critical thinking, and teamwork skills." This webpage includes news about the competitions from recent years.

2011-08-15

86

Mating pheromones of heterobasidiomycetous yeasts  

Science.gov (United States)

Two mating pheromones, which induce mating tube formation, were isolated from Rhodosporidium toruloides (rhodotorucine A) and Tremella mesenterica (tremerogen A-10). These mating pheromones are lipophilic oligopeptides having S-alkylated cysteine at the C-terminus but different amino acid sequences. Synthetic analogues of these pheromones revealed the structure-activity relationships. Metabolism of rhodotorucine A was also studied by using labeled pheromones.

Kamiya, Y.; Sakurai, A.

1981-03-01

87

The evolution of experience-mediated plasticity in mate preferences.  

Science.gov (United States)

Experience of sexual signals can alter mate preferences and influence the course of sexual selection. Here, we examine the patterns of experience-mediated plasticity in mate preferences that can arise in response to variation in the composition of mates in the environment. We use these patterns to test hypotheses about potential sources of selection favouring experience-mediated plasticity. We manipulated signal experience of female Enchenopa treehoppers (Hemiptera: Membracidae) in a vibrational playback experiment with the following treatments: silence; two types of non-preferred signals; preferred signals; and a mixture of preferred and non-preferred signals. This experiment revealed plasticity in mate preference selectivity, with greatest selectivity in the mixed signal treatment, followed by the preferred signal treatment. We found no plasticity in peak preference. These results suggest that females have been selected to adjust preference selectivity according to the variability of potential mates in their social environment, as well as to the presence/absence of preferred mates. We discuss how experience-mediated plasticity in mate preferences can influence the strength of selection on male signals and can result in evolutionary dynamics between variation in preferences and signals that either promote the maintenance of variation or facilitate rapid trait fixation. PMID:22817109

Fowler-Finn, K D; Rodríguez, R L

2012-09-01

88

Cognitive processes underlying human mate choice: The relationship between self-perception and mate preference in Western society.  

Science.gov (United States)

This study tested two hypotheses concerning the cognitive processes underlying human mate choice in Western society: (i) mate preference is conditional in that the selectivity of individuals' mate preference is based on their perception of themselves as long-term partners, and (ii) the decision rule governing such conditional mate preference is based on translating perception of oneself on a given attribute into a comparable selectivity of preference for the same attribute in a mate. Both hypotheses were supported. A two-part questionnaire was completed by 978 heterosexual residents of Ithaca, New York, aged 18-24; they first rated the importance they placed on 10 attributes in a long-term partner and then rated their perception of themselves on those same attributes. Both women and men who rated themselves highly were significantly more selective in their mate preference. When the 10 attributes were grouped into four evolutionarily relevant categories (indicative of wealth and status, family commitment, physical appearance, and sexual fidelity), the greatest amount of variation in the selectivity of mate preference in each category was explained by self-perception in the same category of attributes. We conclude that, in Western society, humans use neither an "opposites-attract" nor a "reproductive-potentials-attract" decision rule in their choice of long-term partners but rather a "likes-attract" rule based on a preference for partners who are similar to themselves across a number of characteristics. PMID:12843405

Buston, Peter M; Emlen, Stephen T

2003-07-22

89

STS-70 Mating  

Science.gov (United States)

Inside the cavernous Vehicle Assembly Building, workers carry out the meticulous process of lifting the orbiter Discovery from a horizontal to a vertical position. Once upright, Discovery will be transferred into a high bay for mating with the external tank/solid rocket booster assembly aready mounted on the mobile launch platform. Completing the assembly process takes about five working days. Discovery's next destination: Launch Pad 39B, and final preparations for liftoff on Mission STS-70 in early June.

1995-01-01

90

Tissue remodeling: a mating-induced differentiation program for the Drosophila oviduct  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background In both vertebrates and invertebrates, the oviduct is an epithelial tube surrounded by visceral muscles that serves as a conduit for gamete transport between the ovary and uterus. While Drosophila is a model system for tubular organ development, few studies have addressed the development of the fly's oviduct. Recent studies in Drosophila have identified mating-responsive genes and proteins whose levels in the oviduct are altered by mating. Since many of these molecules (e.g. Muscle LIM protein 84B, Coracle, Neuroglian have known roles in the differentiation of muscle and epithelia of other organs, mating may trigger similar differentiation events in the oviduct. This led us to hypothesize that mating mediates the last stages of oviduct differentiation in which organ-specific specializations arise. Results Using electron- and confocal-microscopy we identified tissue-wide post-mating changes in the oviduct including differentiation of cellular junctions, remodeling of extracellular matrix, increased myofibril formation, and increased innervation. Analysis of once- and twice-mated females reveals that some mating-responsive proteins respond only to the first mating, while others respond to both matings. Conclusion We uncovered ultrastructural changes in the mated oviduct that are consistent with the roles that mating-responsive proteins play in muscle and epithelial differentiation elsewhere. This suggests that mating triggers the late differentiation of the oviduct. Furthermore, we suggest that mating-responsive proteins that respond only to the first mating are involved in the final maturation of the oviduct while proteins that remain responsive to later matings are also involved in maintenance and ongoing function of the oviduct. Taken together, our results establish the oviduct as an attractive system to address mechanisms that regulate the late stages of differentiation and maintenance of a tubular organ.

Hoy Ronald R

2008-12-01

91

The evolutionary psychology of human mating: a response to Buller's critique.  

Science.gov (United States)

In this paper, I critique arguments made by philosopher David Buller against central evolutionary-psychological explanations of human mating. Specifically, I aim to rebut his criticisms of Evolutionary Psychology regarding (1) women's long-term mating preferences for high-status men; (2) the evolutionary rationale behind men's provisioning of women; (3) men's mating preferences for young women; (4) women's adaptation for extra-pair sex; (5) the sex-differentiated evolutionary theory of human jealousy; and (6) the notion of mate value. In sum, I aim to demonstrate that Buller's arguments contra Evolutionary Psychologists are left wanting. PMID:24927270

Klasios, John

2014-09-01

92

Alterations in serum steroid concentrations in the clearnose skate, Raja eglanteria: correlations with season and reproductive status.  

Science.gov (United States)

Serum steroid hormones in the peripheral circulation of the clearnose skate, Raja eglanteria, were measured at the time of capture and at various times throughout the year while the animals were maintained as a captive breeding population. These analyses demonstrate interesting correlations between changes in hormone concentrations and annual reproductive events. Animals were sampled once (78 females, 20 males) or multiple times (15 females). For both groups of females, 17beta-estradiol was detected throughout the year with significant elevations occurring during October and November when ovarian follicles begin to mature (as determined through necropsy examinations), and January and February when maximum mating activity is observed and egg laying begins. Testosterone and dihydrotestosterone concentrations were significantly elevated in females only during January and February. Testosterone elevations were synchronous with longer-term elevations in 17beta-estradiol in females sampled either once or repetitively. Testosterone concentrations in males were significantly elevated during times of maximum breeding activity compared to periods of sexual inactivity. Data from females sampled during five stages of the egg laying process, as defined by the position of palpable egg capsules within the reproductive tract, revealed that 17beta-estradiol was highest when egg capsules were forming in the nidamental gland (stage 2) or uterus (stage 3); testosterone and dihydrotestosterone were maximal when eggs were in the uterus (stage 3) or cloaca (stage 4); and progesterone was significantly elevated immediately after oviposition (stage 5), suggesting a possible role for progesterone in the regulation of sequential laying of egg pairs. J. Exp. Zool. 284:575-585, 1999. PMID:10469995

Rasmussen, L E; Hess, D L; Luer, C A

1999-10-01

93

Selenium toxicity but not deficient or super-nutritional selenium status vastly alters the transcriptome in rodents  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Protein and mRNA levels for several selenoproteins, such as glutathione peroxidase-1 (Gpx1), are down-regulated dramatically by selenium (Se) deficiency. These levels in rats increase sigmoidally with increasing dietary Se and reach defined plateaus at the Se requirement, making them sensitive biomarkers for Se deficiency. These levels, however, do not further increase with super-nutritional or toxic Se status, making them ineffective for detection of high...

Sunde Roger A; Raines Anna M

2011-01-01

94

Morphological Alterations in Newly Born Dentate Gyrus Granule Cells That Emerge after Status Epilepticus Contribute to Make Them Less Excitable  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Computer simulations of external current stimulations of dentate gyrus granule cells of rats with Status Epilepticus induced by pilocarpine and control rats were used to evaluate whether morphological differences alone between these cells have an impact on their electrophysiological behavior. The cell models were constructed using morphological information from tridimensional reconstructions with Neurolucida software. To evaluate the effect of morphology differences alone, ion channel conduct...

Tejada, Julia?n; Garci?a-cairasco, Norberto; Roque, Antonio C.

2012-01-01

95

Warm and homely or cold and beautiful? Sex differences in trading off traits in mate selection.  

Science.gov (United States)

Prior research and theory suggest that people use three main sets of criteria in mate selection: warmth/trustworthiness, attractiveness/vitality, and status/resources. In two studies, men and women made mating choices between pairs of hypothetical potential partners and were forced to make trade-offs among these three criteria (e.g., warm and homely vs. cold and attractive). As predicted, women (relative to men) placed greater importance on warmth/trustworthiness and status/resources in a potential mate but less importance on attractiveness/vitality. In addition, as expected (a) ratings of ideal standards partly mediated the link between sex and mate choices, (b) ideal standards declined in importance from long-term to short-term relationships, with the exception of attractiveness/vitality, and unexpectedly, (c) sex differences were higher for long-term (compared to short-term) mate choice. Explanations and implications are discussed. PMID:15155031

Fletcher, Garth J O; Tither, Jacqueline M; O'Loughlin, Claire; Friesen, Myron; Overall, Nickola

2004-06-01

96

Mating behavior of Cnephasia jactatana (Lepidoptera: Tortricidae), an important pest of kiwifruit.  

Science.gov (United States)

Understanding mating behavioral sequence helps us identify the mechanisms of mate assessment and choice, and better evaluate behavior-based pest control strategies. Here we describe the mating behavior of Cnephasia jactatana Walker whose females release a sex pheromone, and determine the effect of male mating status on reproductive success. The mating sequence starts when males approach females and display courtship behavior with antennation and fanning wings. Both males and females may end a mating attempt at any stage of the sequence. Both sexes assess their mates from the initial contact to copulation. Females appear to be choosier at the early and mid-stages than at the late stage of the sequence. Virgin males approach and court females significantly earlier than nonvirgin males. As compared with nonvirgin males, virgin males are approximately 1.6 times more likely to approach and 1.8 times more likely to court females, and four times more likely to achieve mating. This may be attributed to depletion of sperm and accessory gland materials and reduced ability to respond to female sex pheromones in nonvirgin males. The number of attempts by males to acquire mates may be one of the traits that females assess before choosing their mates. PMID:23865204

Jiménez-Pérez, Alfredo; Wang, Qiao; Arzuffi, R

2013-06-01

97

The Ca(2+) status of the endoplasmic reticulum is altered by induction of calreticulin expression in transgenic plants  

Science.gov (United States)

To investigate the endoplasmic reticulum (ER) Ca(2+) stores in plant cells, we generated tobacco (Nicotiana tabacum; NT1) suspension cells and Arabidopsis plants with altered levels of calreticulin (CRT), an ER-localized Ca(2+)-binding protein. NT1 cells and Arabidopsis plants were transformed with a maize (Zea mays) CRT gene in both sense and antisense orientations under the control of an Arabidopsis heat shock promoter. ER-enriched membrane fractions from NT1 cells were used to examine how altered expression of CRT affects Ca(2+) uptake and release. We found that a 2.5-fold increase in CRT led to a 2-fold increase in ATP-dependent (45)Ca(2+) accumulation in the ER-enriched fraction compared with heat-shocked wild-type controls. Furthermore, after treatment with the Ca(2+) ionophore ionomycin, ER microsomes from NT1 cells overproducing CRT showed a 2-fold increase in the amount of (45)Ca(2+) released, and a 2- to 3-fold increase in the amount of (45)Ca(2+) retained compared with wild type. These data indicate that altering the production of CRT affects the ER Ca(2+) pool. In addition, CRT transgenic Arabidopsis plants were used to determine if altered CRT levels had any physiological effects. We found that the level of CRT in heat shock-induced CRT transgenic plants correlated positively with the retention of chlorophyll when the plants were transferred from Ca(2+)-containing medium to Ca(2+)-depleted medium. Together these data are consistent with the hypothesis that increasing CRT in the ER increases the ER Ca(2+) stores and thereby enhances the survival of plants grown in low Ca(2+) medium.

Persson, S.; Wyatt, S. E.; Love, J.; Thompson, W. F.; Robertson, D.; Boss, W. F.; Brown, C. S. (Principal Investigator)

2001-01-01

98

Mating changes the female dietary preference in the two-spotted cricket, Gryllus bimaculatus  

Science.gov (United States)

Most insect species exhibit characteristic behavioral changes after mating. Typical post-mating behaviors in female insects include noticeable increases in food intake, elevated oviposition rates, lowered receptivity to courting males, and enhanced immune response. Although it has been reported that mated females of several insect species including the fruit fly, Drosophila melanogaster increase the amount of food intake and change their dietary preferences, the limited number of comparative studies prevent the formulation of generalities regarding post-mating behaviors in other insects in particular amongst orthopteran species. Here, we investigated whether females of the two-spotted cricket, Gryllus bimaculatus, alter their feeding behavior after mating. Although significant differences in the amount of food intake after mating were not observed, all experimental data indicated a clear trend among crickets toward the ingestion of larger quantities of food. Geometric framework analyses revealed that the mated female crickets preferred food with higher protein content compared to virgin female crickets. This implies that this species required different nutritional demands after mating. These findings further expand our understanding of the behavioral and biological changes that are triggered in female insects post-mating, and highlight the potential for this species in investigating the molecular-based nutritional dependent activities that are linked to post-mating behaviors. PMID:24659970

Tsukamoto, Yusuke; Kataoka, Hiroshi; Nagasawa, Hiromichi; Nagata, Shinji

2014-01-01

99

Mating changes the female dietary preference in the two-spotted cricket, Gryllus bimaculatus  

Directory of Open Access Journals (Sweden)

Full Text Available Most insect species exhibit characteristic behavioral changes after mating. Typical post-mating behaviors in female insects include noticeable increases in food intake, elevated oviposition rates, lowered receptivity to courting males, and enhanced immune response. Although it has been reported that mated females of several insect species including the fruit fly, Drosophila melanogaster increase the amount of food intake and change their dietary preferences, the limited number of comparative studies prevent the formulation of generalities regarding post-mating behaviors in other insects in particular amongst orthopteran species. Here, we investigated whether females of the two-spotted cricket, Gryllus bimaculatus, alter their feeding behavior after mating. Although significant differences in the amount of food intake after mating were not observed, all experimental data indicated a clear trend among crickets towards the ingestion of larger quantities of food. Geometric framework analyses revealed that the mated female crickets preferred food with higher protein content compared to virgin female crickets. This implies that this species required different nutritional demands after mating. These findings further expand our understanding of the behavioral and biological changes that are triggered in female insects post-mating, and highlight the potential for this species in investigating the molecular-based nutritional dependent activities that are linked to post-mating behaviors.

ShinjiNagata

2014-03-01

100

Thanatosis as an adaptive male mating strategy in the nuptial gift-giving spider Pisaura mirabilis  

DEFF Research Database (Denmark)

Males and females often experience different optima in mating rate, which may cause evolution of female resistance to matings and male counter adaptations to increase mating rate. Males of the spider Pisaura mirabilis display a spectacular mating behavior involving a nuptial gift and thanatosis (death feigning). Thanatosis in a sexual context is exceptional and was suggested to function as an antipredation strategy toward potentially cannibalistic females. If thanatosis serves as a protection strategy, males should death feign in response to female aggression or when they are more vulnerable to attack. We tested these predictions in a factorial design: males that were handicapped (1 leg removed) and hence vulnerable and control males were paired with females that were more or less aggressive intrinsically (measured toward prey). In mating trials, we recorded the tendency of males to death feign, copulation success, and copulation duration. In addition, we investigated the effect of female mating status (virgin or mated) on these male mating components. Intrinsically aggressive females showed increased mating aggression toward males. Neither female aggressiveness, mating status, nor male vulnerability increased the propensity of males to perform thanatosis. Instead, death-feigning males were more successful in obtaining copulations and gained longer copulations. Hence, our results suggest that thanatosis functions as an adaptive male mating strategy to overcome female resistance. All males were capable of performing thanatosis although some males use it more frequently than others, suggesting a cost of death feigning which maintains the variation in thanatosis during courtship.

Hansen, Line S.; Gonzalez, Sofía F.

2008-01-01

 
 
 
 
101

A character demonstrating the occurrence of mating in male Cactoblastis cactorum (Lepidoptera: Pyralidae)  

International Nuclear Information System (INIS)

The reproductive system of adult male Cactoblastis cactorum, the cactus moth, was examined to determine whether the mating status of males could be ascertained. In unmated males, the posterior portion of the primary ductus ejaculatorius simplex is opaque yellow in color and contains many small football-shaped hyaline granules 3-5 x 5-10 ?m in size. In mated males, the posterior simplex is clear and contains no granules. The presence or absence of these characters was found to be highly reliable and should be of value in determining mating status in marked-recaptured males of this species in a sterile insect release program directed against Cactoblastis. (author)

102

Bioecologia e manejo de Gyropsylla spegazziniana em erva-mate / Bioecology and management of Gyropsylla spegazziniana in yerba mate  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A erva-mate (Ilex paraguariensis St. Hil.) compõe um dos segmentos agroindustriais mais antigos e característicos da região Sul do Brasil, caracterizando-se como uma importante atividade socioeconômica. Para abastecer o mercado consumidor de derivadsupos da erva-mate, foi necessário reflorestar área [...] s com essa planta, o que simplificou o ecossistema e favoreceu algumas espécies de insetos fitófagos, os quais adquiriram status de praga. Nesse contexto, destaca-se a "ampola" da erva-mate Gyropsylla spegazziniana (Hemiptera: Psyllidae) (Lizer e Treles) pela severidade de danos. Não existem inseticidas registrados para o controle dessa praga no Brasil, e diversos estudos apontam para o manejo populacional da praga. Assim, o objetivo desta revisão é reunir informações sobre a bioecologia e as alternativas de manejo de forma a facilitar o entendimento da complexidade do controle de pragas no agroecossistema da erva-mate. Abstract in english Yerba mate (Ilex paraguariensis St. Hil.) composes one of the oldest and more characteristic agribusiness segments of southern Brazil, composing a very important socioeconomic activity. In order to provide the market with yerba mate derivatives, it was necessary to reforest areas with this species, [...] which simplified the ecosystem and generated impacts that favored some species of phytophagous insects, and then they acquired blight status. In this context, we indicate Gyropsylla spegazziniana (Hemiptera, Psyllidae) (Lizer e Treles) by the severity of the damage. There is no registered insecticide to control this pest in Brazil, and several studies point out to handling the population of this blight. The objective of this review is to gather information on bioecology and alternatives to control this insect in order to explain the complexity of pest control in yerba mate agroecosystem.

Ionete Lucia Milani, Barzotto; Luis Francisco Angeli, Alves.

103

Resources, attractiveness, family commitment; reproductive decisions in human mate choice.  

Science.gov (United States)

This study of reproductive decisions in human mate selection used data from "lonely hearts" advertisements to examine a series of predictions based on the mate preferences of male and females relating to age; physical appearance; financial condition and socioeconomic status; family commitment and personal traits; short- and long-term mating; and marital status and preexisting children. The sample consisted of 1000 personal advertisements (500 male) placed in two daily, national papers between February and October 1994 in Hungary. The research procedure included a pilot study of 150 advertisers (75 male) to refine the categories examined. Analysis was performed using 1) a matrix with one axis referring to offers and the other to demands of males and females separately; 2) a matrix of offers only to derive correlated traits of claims by males and females; and 3) a matrix with columns describing sex, offers, demands, advertiser's age, and required age and a row for each of the 1000 samples. It was found that men preferred younger mates, while women preferred older ones. Men were more likely to seek physical attractiveness, while women were more likely to seek financial resources (ranked 7th) and high status (ranked 6th). Women strongly preferred male domestic virtue and family commitment, and twice as many women as men demanded long-term relationships. Women more frequently declared preexisting children, and men exhibited a reluctance to accept these children. Both males and females employed "trade-off" strategies, making greater demands if they felt they had attractive offers. PMID:12293453

Bereczkei, T; Voros, S; Gal, A; Bernath, L

1997-08-01

104

MATE. Multi Aircraft Training Environment  

DEFF Research Database (Denmark)

A medium fidelity and low cost training device for pilots, called the Multi Aircraft Training Environment (MATE), is developed to replace other low fidelity stand-alone training devices and integrate them into a flexible environment, primarily aimed attraining pilots in checklist procedures. The cockpit switches and instruments in MATE are computer-generated graphics. The graphics are back projected onto semi-transparent touch screen panels in a hybrid cockpit mock-up. Thus, the MATE is relativelycheap, it is always available, it is reconfigurable (e.g. between types of aircraft/models to be simulated) and with possibilities for including various forms of intelligent computer assistance. This training concept and the technology are not specific toaviation, but can be used to simulate various types of control panels in different domains. The training effectiveness of pilots' procedure training in the MATE prototype was compared with the effects of traditional training that included the use of realaircraft. The experimental group (EXP) trained the pre-start checklist and the engine start checklist for the Saab 340 commuter aircraft in a MATE prototype. The control group (CTR) trained the same procedures using the aircraft (a/c) for training the prestart and a desktop computer tool (power plant trainer) for training engine starts. Performance on the pre-start checklist was compared in a formal checkout that took place in the a/c. Performance on the engine start procedure was compared in a fullflight simulator (FFS). The conclusion was, firstly, that training in the MATE prototype can result in an equally good performance as the existing training (a/c and computer tools), provided that the MATE trainees are given time to familiarise themselveswith the a/c. Secondly, training in MATE can result in better performance during dynamic tasks, such as abnormal engine starts. This is promising for the further development of the MATE concept.

Hauland, G.; Andersen, Henning Boje

2002-01-01

105

Prior mating success can affect allocation towards future sexual signaling in crickets  

Science.gov (United States)

Fitness is often correlated with the expression level of a sexually selected trait. However, sexually selected traits are costly to express such that investment in their expression should be optimised to maximize their overall fitness gains. Social interactions, in the form of successful and unsuccessful matings, may offer males one type of feedback allowing them to gauge how to allocate their resources towards sexual signaling. Here we tested whether adult male black field crickets (Teleogryllus commodus) modify the extent of their calling effort (the sexually selected trait) in response to successful and unsuccessful matings with females. To examine the effect that mating interactions with females have on investment into sexual signaling, we monitored male calling effort after maturation and then provided males with a female at two points within their life, manipulating whether or not males were able to successfully mate each time. Our results demonstrate that males alter their investment towards sexual signaling in response to successful matings, but only if the experience occurs early in their life. Males that mated early decreased their calling effort sooner than males that were denied a mating. Our results demonstrate that social feedback in the form of successful and unsuccessful matings has the potential to alter the effort a male places towards sexual signaling. PMID:25392758

Chiswell, Rachel; Girard, Madeline; Fricke, Claudia

2014-01-01

106

Prior mating success can affect allocation towards future sexual signaling in crickets.  

Science.gov (United States)

Fitness is often correlated with the expression level of a sexually selected trait. However, sexually selected traits are costly to express such that investment in their expression should be optimised to maximize their overall fitness gains. Social interactions, in the form of successful and unsuccessful matings, may offer males one type of feedback allowing them to gauge how to allocate their resources towards sexual signaling. Here we tested whether adult male black field crickets (Teleogryllus commodus) modify the extent of their calling effort (the sexually selected trait) in response to successful and unsuccessful matings with females. To examine the effect that mating interactions with females have on investment into sexual signaling, we monitored male calling effort after maturation and then provided males with a female at two points within their life, manipulating whether or not males were able to successfully mate each time. Our results demonstrate that males alter their investment towards sexual signaling in response to successful matings, but only if the experience occurs early in their life. Males that mated early decreased their calling effort sooner than males that were denied a mating. Our results demonstrate that social feedback in the form of successful and unsuccessful matings has the potential to alter the effort a male places towards sexual signaling. PMID:25392758

Chiswell, Rachel; Girard, Madeline; Fricke, Claudia; Kasumovic, Michael M

2014-01-01

107

Sex similarities and differences in preferences for short-term mates: what, whether, and why.  

Science.gov (United States)

Are there sex differences in criteria for sexual relationships? The answer depends on what question a researcher asks. Data suggest that, whereas the sexes differ in whether they will enter short-term sexual relationships, they are more similar in what they prioritize in partners for such relationships. However, additional data and context of other findings and theory suggest different underlying reasons. In Studies 1 and 2, men and women were given varying "mate budgets" to design short-term mates and were asked whether they would actually mate with constructed partners. Study 3 used a mate-screening paradigm. Whereas women have been found to prioritize status in long-term mates, they instead (like men) prioritize physical attractiveness much like an economic necessity in short-term mates. Both sexes also show evidence of favoring well-rounded long- and short-term mates when given the chance. In Studies 4 and 5, participants report reasons for having casual sex and what they find physically attractive. For women, results generally support a good genes account of short-term mating, as per strategic pluralism theory (S. W. Gangestad & J. A. Simpson, 2000). Discussion addresses broader theoretical implications for mate preference, and the link between method and theory in examining social decision processes. PMID:16594832

Li, Norman P; Kenrick, Douglas T

2006-03-01

108

Future oceanic warming and acidification alter immune response and disease status in a commercial shellfish species, Mytilus edulis L.  

Science.gov (United States)

Increases in atmospheric carbon dioxide are leading to physical changes in marine environments including parallel decreases in ocean pH and increases in seawater temperature. This study examined the impacts of a six month exposure to combined decreased pH and increased temperature on the immune response and disease status in the blue mussel, Mytilus edulis L. Results provide the first confirmation that exposure to future acidification and warming conditions via aquarium-based simulation may have parallel implications for bivalve health. Collectively, the data suggests that temperature more than pH may be the key driver affecting immune response in M. edulis. Data also suggests that both increases in temperature and/or lowered pH conditions may lead to changes in parasite abundance and diversity, pathological conditions, and bacterial incidence in M. edulis. These results have implications for future management of shellfish under a predicted climate change scenario and future sustainability of shellfisheries. Examination of the combined effects of two stressors over an extended exposure period provides key preliminary data and thus, this work represents a unique and vital contribution to current research efforts towards a collective understanding of expected near-future impacts of climate change on marine environments. PMID:24927423

Mackenzie, Clara L; Lynch, Sharon A; Culloty, Sarah C; Malham, Shelagh K

2014-01-01

109

Future Oceanic Warming and Acidification Alter Immune Response and Disease Status in a Commercial Shellfish Species, Mytilus edulis L.  

Science.gov (United States)

Increases in atmospheric carbon dioxide are leading to physical changes in marine environments including parallel decreases in ocean pH and increases in seawater temperature. This study examined the impacts of a six month exposure to combined decreased pH and increased temperature on the immune response and disease status in the blue mussel, Mytilus edulis L. Results provide the first confirmation that exposure to future acidification and warming conditions via aquarium-based simulation may have parallel implications for bivalve health. Collectively, the data suggests that temperature more than pH may be the key driver affecting immune response in M. edulis. Data also suggests that both increases in temperature and/or lowered pH conditions may lead to changes in parasite abundance and diversity, pathological conditions, and bacterial incidence in M. edulis. These results have implications for future management of shellfish under a predicted climate change scenario and future sustainability of shellfisheries. Examination of the combined effects of two stressors over an extended exposure period provides key preliminary data and thus, this work represents a unique and vital contribution to current research efforts towards a collective understanding of expected near-future impacts of climate change on marine environments. PMID:24927423

Mackenzie, Clara L.; Lynch, Sharon A.; Culloty, Sarah C.; Malham, Shelagh K.

2014-01-01

110

Altered redox status in Escherichia coli cells enhances pyruvate production in pH-adjusting culture with a fermenter.  

Science.gov (United States)

Improvements in pyruvate production process were examined using Escherichia coli BW25113Dpta/ pHfdh strain carrying the formate dehydrogenase gene of Mycobacterium vaccae to change the redox status of the cells. Glucose and formate concentrations, and oxygenation levels determined previously in a shake-flask culture were applied for pyruvate production in a 1 l fermenter. However, pyruvate was not produced under the examined conditions. Detailed pH measurements during the fermenter culture using CaCO3 revealed that maintaining the pH value around 6.0 plays an important role in stabilizing the pyruvate accumulation. In the pH-adjusting culture around 6.0 with NaOH solution, the concentration and yield of pyruvate were 8.96 g l-1 and 0.48 g pyruvate g glucose-1, respectively, which were significantly higher than the values reported in the shake-flask culture (6.79 g l-1 and 0.32 g pyruvate g glucose-1). PMID:23797477

Ojima, Yoshihiro; Matsuo, Nahoko; Suparman, Asep; Suryadarma, Prayoga; Taya, Masahito

2014-03-01

111

Lactational cadmium exposure induced alterations in the hematological indices and oxidative status in brain, liver and testes of rat pups  

Directory of Open Access Journals (Sweden)

Full Text Available This study was carried out to investigate the effect of lactational exposure to    cadmium (Cd on suckling male rat pups. Hematological parameters, antioxidant status, some biochemical and pathophysiological indices in brain, liver and testicular tissues of rat offspring were studied. Lactating Sprague–Dawley females received either 0 ppb (control or 20 ppm Cd as CdCl2 in their drinking water during the lactational period. Suckling male rat pups were weaned and sacrificed on day 24 for performing various biochemical assays. Distortion of the hemopoietic features as decrease in RBCs count, hemoglobin, hematocrit and platelet values were seen in exposed rat pups. Increased lipid peroxidation malondialdehyde (MDA and depressed antioxidant defense superoxide dimutase (SOD levels in brain, liver and testes of exposed rat pups were obtained.  Serum activities of alkaline phosphatase (ALP and lactate dehydrogenase (LDH showed a significant increase, whereas a reduction in the level of testosterone hormone was obtained in cadmium exposed pups. In addition, Cd induces neuronal degeneration, necrosis in hepatocytes and degeneration in semineferous tubules along with interstitial edema. The previous findings are indicative of multiple targets of cadmium to disrupt several organ functions in newly borne rat pups on lactational exposure.

E. E. Elsharkawy

2012-09-01

112

Sex and age differences in mate-selection preferences.  

Science.gov (United States)

For nearly 70 years, studies have shown large sex differences in human mate selection preferences. However, most of the studies were restricted to a limited set of mate selection criteria and to college students, and neglecting relationship status. In this study, 21,245 heterosexual participants between 18 and 65 years of age (mean age 41) who at the time were not involved in a close relationship rated the importance of 82 mate selection criteria adapted from previous studies, reported age ranges for the oldest and youngest partner that they would find acceptable, and responded to 10 yes/no questions about a potential marriage partner. For nearly all mate selection criteria, women were found to be the more demanding sex, although men placed consistently more value on the physical attractiveness of a potential partner than women. Also, the effects of the participants' age and level of education were nearly negligible. These results demonstrate the robustness of sex differences in mate selection criteria across a substantial age range. PMID:22941269

Schwarz, Sascha; Hassebrauck, Manfred

2012-12-01

113

Effects of mating rates on oviposition, sex ratio and longevity in a predatory mite Neoseiulus cucumeris (Acari: Phytoseiidae).  

Science.gov (United States)

Two aspects of mating effects on the fecundity, sex ratio and longevity of Neoseiulus cucumeris (Acari: Phytoseiidae) were examined in laboratory experiments: (1) females mated by one, two or three different males (unmated and 3 days old) at 5-day intervals, and (2) females mated by males with different age/mating status (number of females mated previously by the male). Females allowed to mate with a second or third male at 5-day intervals produced 39 eggs on average, but those mated with a single male produced 28 eggs on average. Matings with additional males 5 or 10 days after the first male increased the duration of the oviposition period of these females by 5-7 days and at the same time reduced the post-oviposition period by about 10 days. Overall, females with additional matings by one or two different males at 5-day intervals survived a few days shorter than females without additional males. Mating with a different female each day, a male of N. cucumeris could mate with 5-8 females, which produced a total of 85-116 eggs: females mated with a male during days 1 and 2 in its adulthood and with a male of the last 2 days of life (days 7 and 8) produced about half as many eggs as females mated with a male during 3-6 days of its adulthood. Females mated with males that are too young or too old had a shorter oviposition period and a longer post-oviposition period and longevity than females mated with middle-aged males. In both experiments, rates of oviposition remained similar in females with high or low fecundity. This indicates that in both cases, the increased fecundity is due to the extension of the oviposition period through additional sperm supplied by the second male and or third male (in experiment 1) or more sperm by males not too young nor too old (experiment 2). PMID:17968663

Ji, Jie; Zhang, Zhi-Qiang; Zhang, Yanxuan; Chen, Xia; Lin, Jianzhen

2007-01-01

114

Assessing the mating 'health' of commercial honey bee queens.  

Science.gov (United States)

Honey bee queens mate with multiple males, which increases the total genetic diversity within colonies and has been shown to confer numerous benefits for colony health and productivity. Recent surveys of beekeepers have suggested that 'poor queens' are a top management concern, thus investigating the reproductive quality and mating success of commercially produced honey bee queens is warranted. We purchased 80 commercially produced queens from large queen breeders in California and measured them for their physical size (fresh weigh and thorax width), insemination success (stored sperm counts and sperm viability), and mating number (determined by patriline genotyping of worker offspring). We found that queens had an average of 4.37 +/- 1.446 million stored sperm in their spermathecae with an average viability of 83.7 +/- 13.33%. We also found that the tested queens had mated with a high number of drones (average effective paternity frequency: 17.0 +/- 8.98). Queen "quality" significantly varied among commercial sources for physical characters but not for mating characters. These findings suggest that it may be more effective to improve overall queen reproductive potential by culling lower-quality queens rather than systematically altering current queen production practices. PMID:22420250

Tarpy, David R; Keller, Jennifer J; Caren, Joel R; Delaney, Deborah A

2012-02-01

115

STS-88 Mating in VAB  

Science.gov (United States)

The orbiter Endeavour is suspended in a vertical position inside the Vehicle Assembly Building where it will be mated with its solid rocket boosters and external tank. Endeavour is scheduled to fly on mission STS-88, the first Space Shuttle flight for the assembly of the International Space Station, on December 3, 1998. The primary payload on the mission is the Unity connecting module, which will be mated to the Russian-built Zarya Control Module already in orbit at that time.

1998-01-01

116

Alterations in selenium status influences reproductive potential of male mice by modulation of transcription factor NFkappaB.  

Science.gov (United States)

Selenium (Se), an essential dietary trace element, is required for the maintenance of male fertility. In order to study its role in spermatogenesis, Balb/c mice with different Se status (Se deficient, group I; adequate, group II and excess, group III) were generated by feeding yeast based Se deficient diet for group I and deficient diet supplemented with Se as sodium selenite at adequate (0.2 ppm) and excess (1 ppm) for group II and III, respectively, for a period of 4 and 8 weeks. Percentage fertility was reduced in group I and III as compared to group II. A significant decrease in Se levels and glutathione peroxidase (GSH-Px) activity were observed in group I animals, whereas increase in GSH-Px activity was seen in group III. Further, significant increase in lipid peroxidation was observed in both Se deficient and excess groups. This indicated that dietary manipulation of Se levels either deficiency or excess leads to increased oxidative stress. Nuclear factor kappa B (NFkappaB), a well-known redox regulated transcription factor has also been suggested to play a crucial role in spermatogenesis. The expression of both p65 and p50 genes (components of NFkappaB) increased in Se deficient group I mice while the expression of the inhibitory IkappaBalpha declined significantly. This indicated activation of NFkappaB in Se deficiency. We also studied iNOS expression, which is a known target gene of NFkappaB, by RT-PCR. Significant elevation in the iNOS levels as well as NO levels was recorded. Both enhanced NO levels and NFkappaB are harmful in the progression of normal spermatogenic cycle. Therefore, present result clearly demonstrates the effect of reduced supply of Se on up-regulation and activation of NFkappaB in testis and its influence on spermatogenesis. PMID:16758115

Shalini, Sonia; Bansal, M P

2007-02-01

117

Alteration of DNA ploidy status and cell proliferation induced by preoperative radiotherapy is a prognostic factor in rectal cancer.  

Science.gov (United States)

To identify predictors of prognosis after preoperative radiotherapy, DNA ploidy and cell proliferation were investigated in 116 patients with rectal cancer. For flow cytometry, a nuclear suspension was prepared by pepsin digestion of paraffin samples of biopsies taken before preoperative radiotherapy (15 x 2 Gy) and also of the resected rectal tumors after radiotherapy. The median follow-up period was 6 years. The proportion of tumor necrosis was evaluated in histological sections before and after irradiation. There was a significant decrease (74 to 48%) in aneuploid tumors after radiation. Of 86 patients with aneuploid biopsies, 28 revealed no reduction in the proportion of aneuploid tumor cells [group AN(=/increase)], and 58 showed a reduction (mean 48.9%) or complete elimination of aneuploid tumor cells [group AN(decrease/psi)]. The incidence of local or distal failure was significantly reduced in the group AN(decrease/psi) (7.8%/20%), compared with the group AN (=/increase) (27%/54%) and the group of constant diploid tumors (n = 22; 13.6%/31.8 %; P = 0.034). There was a trend of decreased recurrence rate in diploid tumors with a reduced fraction of cells in S-phase after radiotherapy. Survival was significantly increased in group AN(decrease/psi) (P < 0.0001). In a multivariate regression analysis, variables of independent prognostic significance were increased proportion of necrosis after irradiation and DNA ploidy group and the postoperative tumor stage. These results suggest that alterations in tumor DNA ploidy and cell proliferation induced by preoperative radiotherapy might help to identify patients likely to benefit from preoperative radiation in rectal cancer. PMID:10955806

Lammering, G; Taher, M M; Gruenagel, H H; Borchard, F; Porschen, R

2000-08-01

118

Severe exercise and exercise training exert opposite effects on human neutrophil apoptosis via altering the redox status.  

Science.gov (United States)

Neutrophil spontaneous apoptosis, a process crucial for immune regulation, is mainly controlled by alterations in reactive oxygen species (ROS) and mitochondria integrity. Exercise has been proposed to be a physiological way to modulate immunity; while acute severe exercise (ASE) usually impedes immunity, chronic moderate exercise (CME) improves it. This study aimed to investigate whether and how ASE and CME oppositely regulate human neutrophil apoptosis. Thirteen sedentary young males underwent an initial ASE and were subsequently divided into exercise and control groups. The exercise group (n?=?8) underwent 2 months of CME followed by 2 months of detraining. Additional ASE paradigms were performed at the end of each month. Neutrophils were isolated from blood specimens drawn at rest and immediately after each ASE for assaying neutrophil spontaneous apoptosis (annexin-V binding on the outer surface) along with redox-related parameters and mitochondria-related parameters. Our results showed that i) the initial ASE immediately increased the oxidative stress (cytosolic ROS and glutathione oxidation), and sequentially accelerated the reduction of mitochondrial membrane potential, the surface binding of annexin-V, and the generation of mitochondrial ROS; ii) CME upregulated glutathione level, retarded spontaneous apoptosis and delayed mitochondria deterioration; iii) most effects of CME were unchanged after detraining; and iv) CME blocked ASE effects and this capability remained intact even after detraining. Furthermore, the ASE effects on neutrophil spontaneous apoptosis were mimicked by adding exogenous H(2)O(2), but not by suppressing mitochondrial membrane potential. In conclusion, while ASE induced an oxidative state and resulted in acceleration of human neutrophil apoptosis, CME delayed neutrophil apoptosis by maintaining a reduced state for long periods of time even after detraining. PMID:21931703

Syu, Guan-Da; Chen, Hsiun-Ing; Jen, Chauying J

2011-01-01

119

Clinical implications of altered thyroid status in male testicular function / Implicações clínicas das alterações tireoidianas na função gonadal masculina  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Os hormônios da tireoide estão envolvidos virtualmente no desenvolvimento e na manutenção de todos os tecidos. As gônadas masculinas foram, por décadas, consideradas insensíveis aos hormônios tireoidianos. No entanto, estudos mais recentes têm demonstrado que disfunções tireoidianas estão associadas [...] não somente a anormalidades na morfologia e na função dos testículos, mas também à diminuição da fertilidade e alterações na atividade sexual masculina. Atualmente, o papel da triiodotironina (T3) no controle da proliferação das células de Sertoli e Leydig, maturação testicular e esteroidogênese é amplamente aceito, bem como a presença de transportadores e receptores para o hormônio tireoidiano nos testículos durante o período de desenvolvimento e a idade adulta. No entanto, apesar dos dados que indicam que o T3 atua diretamente nos testículos humanos, persistem controvérsias em relação ao impacto das doenças tireoidianas sobre a espermatogênese e a fertilidade, o que pode ser em parte devido à escassez de estudos clínicos nessa área. Essa revisão tem por objetivo apresentar um panorama de dados clínicos atualizados sobre o papel dos hormônios tireoidianos na função gonadal masculina. Abstract in english Thyroid hormones are involved in the development and maintenance of virtually all tissues. Although for many years the testis was thought to be a thyroid-hormone unresponsive organ, studies of the last decades have demonstrated that thyroid dysfunction is associated not only with abnormalities in mo [...] rphology and function of testes, but also with decreased fertility and alterations of sexual activity in men. Nowadays, the participation of triiodothyronine (T3) in the control of Sertoli and Leydig cell proliferation, testicular maturation, and steroidogenesis is widely accepted, as well as the presence of thyroid hormone transporters and receptors in testicular cells throughout the development process and in adulthood. But even with data suggesting that T3 may act directly on these cells to bring about its effects, there is still controversy regarding the impact of thyroid diseases on human spermatogenesis and fertility, which can be in part due to the lack of well-controlled clinical studies. The current review aims at presenting an updated picture of recent clinical data about the role of thyroid hormones in male gonadal function.

Simone Magagnin, Wajner; Márcia Santos, Wagner; Ana Luiza, Maia.

2009-11-01

120

MHC-dependent mate preferences in humans.  

Science.gov (United States)

One substantial benefit of sexual reproduction could be that it allows animals (including humans) to react rapidly to a continuously changing environmental selection pressure such as coevolving parasites. This counteraction would be most efficient if the females were able to provide their progeny with certain allele combinations for loci which may be crucial in the parasite-host arms race, for example the MHC (major histocompatibility complex). Here we show that the MHC influences both body odours and body odour preferences in humans, and that the women's preferences depend on their hormonal status. Female and male students were typed for their HLA-A, -B and -DR. Each male student wore a T-shirt for two consecutive nights. The next day, each female student was asked to rate the odours of six T-shirts. They scored male body odours as more pleasant when they differed from the men in their MHC than when they were more similar. This difference in odour assessment was reversed when the women rating the odours were taking oral contraceptives. Furthermore, the odours of MHC-dissimilar men remind the test women more often of their own actual or former mates than do the odours of MHC-similar men. This suggests that the MHC or linked genes influence human mate choice today. PMID:7630893

Wedekind, C; Seebeck, T; Bettens, F; Paepke, A J

1995-06-22

 
 
 
 
121

Skin fibroblasts from pantothenate kinase-associated neurodegeneration patients show altered cellular oxidative status and have defective iron-handling properties.  

Science.gov (United States)

Pantothenate kinase-associated neurodegeneration (PKAN) is a neurodegenerative disease belonging to the group of neurodegeneration with brain iron accumulation disorders. It is characterized by progressive impairments in movement, speech and cognition. The disease is inherited in a recessive manner due to mutations in the Pantothenate Kinase-2 (PANK2) gene that encodes a mitochondrial protein involved in Coenzyme A synthesis. To investigate the link between a PANK2 gene defect and iron accumulation, we analyzed primary skin fibroblasts from three PKAN patients and three unaffected subjects. The oxidative status of the cells and their ability to respond to iron were analyzed in both basal and iron supplementation conditions. In basal conditions, PKAN fibroblasts show an increase in carbonylated proteins and altered expression of antioxidant enzymes with respect to the controls. After iron supplementation, the PKAN fibroblasts had a defective response to the additional iron. Under these conditions, ferritins were up-regulated and Transferrin Receptor 1 (TfR1) was down-regulated to a minor extent in patients compared with the controls. Analysis of iron regulatory proteins (IRPs) reveals that, with respect to the controls, PKAN fibroblasts have a reduced amount of membrane-associated mRNA-bound IRP1, which responds imperfectly to iron. This accounts for the defective expression of ferritin and TfR1 in patients' cells. The inaccurate quantity of these proteins produced a higher bioactive labile iron pool and consequently increased iron-dependent reactive oxygen species formation. Our results suggest that Pank2 deficiency promotes an increased oxidative status that is further enhanced by the addition of iron, potentially causing damage in cells. PMID:22692681

Campanella, Alessandro; Privitera, Daniela; Guaraldo, Michela; Rovelli, Elisabetta; Barzaghi, Chiara; Garavaglia, Barbara; Santambrogio, Paolo; Cozzi, Anna; Levi, Sonia

2012-09-15

122

The Structure and Content of Long-Term and Short-Term Mate Preferences  

Directory of Open Access Journals (Sweden)

Full Text Available This study addresses two limitations in the mate preferences literature. First, research all-too-often relies on single-item assessments of mate preferences precluding more advanced statistical techniques like factor analysis. Second, when factor analysis could be done, it exclusively has done for long-term mate preferences, at the exclusion of short-term mate preferences. In this study (N = 401, we subjected 20 items designed to measure short- and long-term mate preferences to both principle components (n = 200 and confirmatory factor analysis (n = 201. In the long-term context, we replicated previous findings that there are three different categories of preferences: physical attractiveness, interpersonal warmth, and social status. In the short-term context, physical attractiveness occupied two parts of the structure, social status dropped out, and interpersonal warmth remained. Across short- and long-term contexts, there were slight changes in what defined the shared dimensions (i.e., physical attractiveness and interpersonal warmth, suggesting prior work that applies the same inventory to each context might be flawed. We also replicated sex differences and similarities in mate preferences and correlates with sociosexuality and mate value. We adopt an evolutionary paradigm to understand our results.

Peter K. Jonason

2013-12-01

123

F1 sterility of Diatraea saccharalis (Fab.), Lepidoptera: Crambidae. II. mating dynamics and effects on progeny  

International Nuclear Information System (INIS)

The effect of irradiation of Diatraea saccharalis pupae at substerilizing gamma doses on the competitiveness of adult males emerging from the irradiated pupae and on their sterile progeny was evaluated on the basis of mating dynamics, mating duration and the length of the pre-mating period, as well as the sex ratio and the variation of pupal weights in the progeny. It is concluded that substerilizing gamma doses do not affect the indicators evaluated and that in the progeny the sex ratio is altered in favour of males and F1 pupal weights are reduced significantly. (author). 8 refs, 3 figs, 2 tabs

124

Mating type and pheromone genes in the Gibberella fujikuroi species complex : and evolutionary perspective  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Reproductive isolation is an essential stage in speciation. In Ascomycetes, the ubiquitous distribution of many species suggests that sympatric speciation through assertive mating should be an important factor. The MAT locus and the pheromone/receptor system could both potentially contribute to the development of such sexual isolation. Alterations at the MAT loci could lead to distinct reproductive habits or a change in mating system, both of which can reduce gene-flow between species. Howeve...

Martin, Simon Henry

2011-01-01

125

MHC-correlated mate choice in humans: a review.  

Science.gov (United States)

Extremely high variability in genes of the major histocompatibility complex (MHC) in vertebrates is assumed to be a consequence of frequency-dependent parasite-driven selection and mate preferences based on promotion of offspring heterozygosity at MHC, or potentially, genome-wide inbreeding avoidance. Where effects have been found, mate choice studies on rodents and other species usually find preference for MHC-dissimilarity in potential partners. Here we critically review studies on MHC-associated mate choice in humans. These are based on three broadly different aspects: (1) odor preferences, (2) facial preferences and (3) actual mate choice surveys. As in animal studies, most odor-based studies demonstrate disassortative preferences, although there is variation in the strength and nature of the effects. In contrast, facial attractiveness research indicates a preference for MHC-similar individuals. Results concerning MHC in actual couples show a bias towards similarity in one study, dissimilarity in two studies and random distribution in several other studies. These vary greatly in sample size and heterogeneity of the sample population, both of which may significantly bias the results. This pattern of mixed results across studies may reflect context-dependent and/or life history sensitive preference expression, in addition to higher level effects arising out of population differences in genetic heterogeneity or cultural and ethnic restrictions on random mating patterns. Factors of special relevance in terms of individual preferences are reproductive status and long- vs. short-term mating context. We discuss the idea that olfactory and visual channels may work in a complementary way (i.e. odor preference for MHC-dissimilarity and visual preference for MHC-similarity) to achieve an optimal level of genetic variability, methodological issues and interesting avenues for further research. PMID:19054623

Havlicek, Jan; Roberts, S Craig

2009-05-01

126

Reinforcement shapes clines in female mate discrimination in Drosophila subquinaria.  

Science.gov (United States)

Reinforcement of species boundaries may alter mate recognition in a way that also affects patterns of mate preference among conspecific populations. In the fly Drosophila subquinaria, females sympatric with the closely related species D. recens reject mating with heterospecific males as well as with conspecific males from allopatric populations. Here, we assess geographic variation in behavioral isolation within and among populations of D. subquinaria and use cline theory to understand patterns of selection on reinforced discrimination and its consequences for sexual isolation within species. We find that selection has fixed rejection of D. recens males in sympatry, while significant genetic variation in this behavior occurs within allopatric populations. In conspecific matings sexual isolation is also asymmetric and stronger in populations that are sympatric with D. recens. The clines in behavioral discrimination within and between species are similar in shape and are maintained by strong selection in the face of gene flow, and we show that some of their genetic basis may be either shared or linked. Thus, while reinforcement can drive extremely strong phenotypic divergence, the long-term consequences for incipient speciation depend on gene flow, genetic linkage of discrimination traits, and the cost of these behaviors in allopatry. PMID:25163510

Bewick, Emily R; Dyer, Kelly A

2014-11-01

127

Mate choice decisions by searchers  

Directory of Open Access Journals (Sweden)

Full Text Available For more than two decades rudimentary versions of the fixed sample and sequential search strategies have provided the primary theoretical foundation for the study of mate choice decisions by searchers. The theory that surrounds these models has expanded markedly over this time period. In this paper, we review and extend results derived from these models, with a focus on the empirical analysis of searcher behavior. The basic models are impractical for empirical purposes because they rely on the assumption that searchers—and, for applied purposes, researchers—assess prospective mates based on their quality, the fitness consequences of mate choice decisions. Here we expound versions of the models that are more empirically useful, reformulated to reflect decisions based on male phenotypic characters. For some organisms, it may be possible to use preference functions to derive predictions from the reformulated models and thereby avoid difficulties associated with the measurement of male quality per se. But predictions derived from the two models are difficult to differentiate empirically, regardless of how the models are formulated. Here we develop ideas that illustrate how this goal might be accomplished. In addition, we clarify how the variability of male quality should be evaluated and we extend what is known about how this variability influences searcher behavior under each model. More general difficulties associated with the empirical study of mate choice decisions by searchers are also discussed [Current Zoology 59 (2: 184–199, 2013].

Daniel D. WIEGMANN, Lisa M. ANGELONI, Steven M. SEUBERT, J. Gordon WADE

2013-04-01

128

Mate Selection: A Propositional Formulation.  

Science.gov (United States)

With the intent of integrating partial theories that have developed in the area of mate selection, this paper presents propositions extracted from the research literature (1950-1976). A logical ordering of these propositions is suggested and new propositions are derived by interrelating selected propositions. These conclusions are reached: first,…

Roosa, Mark W.

129

Active phenotypic assortment in mate selection: self-descriptions and sought-for attributes of mates in dating advertisements.  

Science.gov (United States)

Assortative mating results both from social homogamy (coming for similar environments) and active phenotypic assortment (seeking a mate with desired attributes). Dating advertisements provide a means of assessing the role of active phenotypic assortment in the absence of social homogamy. The relative frequency of mention of different attributes (given limited advertising space) is informative regarding the salience of these attributes in active phenotypic assortment. Sex differences in self descriptions and in attributes desired in others in dating advertisements provide a means of evaluating sociobiological issues. Data were analyzed from 191 ads placed by females and 253 ads placed by males seeking to meet members of the opposite sex. The most frequently mentioned attributes are age, race, occupation, moral characteristics, and physical attractiveness. While close to 80 per cent of the advertisers provided information concerning their own race/ethnicity, only a minority of those providing such information limited their quest for a partner to members of their own race/ethnicity. There is substantial assortative mating for religion, family background, status, and educational attainment, yet these attributes are rarely (religion and education) or never (family background) mentioned in advertisements, suggesting that assortative mating on these dimensions may be solely a consequence of social homogamy. PMID:9446965

Sakai, D K; Johnson, R C

1997-01-01

130

Density affects mating mode and large male mating advantage in a fiddler crab.  

Science.gov (United States)

Fiddler crabs show two different mating modes: either females search and crabs mate underground in male burrows, or males search and crabs mate on the surface near female burrows. We explored the relationship between crab density, body size, the searching behavior of both sexes, and the occurrence of both mating modes in the fiddler crab Uca uruguayensis. We found that crabs change their mating mode depending on their size and crab density. Crabs mated mostly on the surface at low densities, and underground at high densities. The proportion of wandering receptive females but not courting males accounted for the variation in mating modes. This suggests that whether crabs mate underground (or on the surface) is determined by the presence (or absence) of searching females. We found that the change in the mating mode affected the level of assortative mating; males mating underground were bigger than those mating on the surface, suggesting active female choice. Given that fiddler crabs experience multiple reproductive cycles, they are prone to showing behavioral plasticity in their mating strategy whenever the payoffs of using different mating modes differ between reproductive events. Our results suggest that the incorporation of different levels of environmental variability may be important in theoretical models aimed at improving our understanding of the evolution of alternative mating tactics and strategies. PMID:20931233

Ribeiro, Pablo D; Daleo, Pedro; Iribarne, Oscar O

2010-12-01

131

Mating behavior of Diabrotica speciosa (Coleoptera: Chrysomelidae).  

Science.gov (United States)

Diabrotica speciosa (Germar) is an economically important pest of Neotropical cultures and represents a quarantine risk for Neartic and Paleartic Regions. Despite its agricultural importance, few studies have been done on mating behavior and chemical communication, which has delayed the development of behavioral techniques for population management, such as the use of pheromone traps. In this study, we determined 1) the age at first mating; 2) diel rhythm of matings; 3) number of matings over 7 d; 4) the sequence of D. speciosa activities during premating, mating, and postmating; 5) the duration of each activity; and 6) response to male and female conspecific volatiles in Y-tube olfactometer. The first mating occurred between the third and seventh day after adult emergence and the majority of pairs mated on the fourth day after emergence. Pairs of D. speciosa showed a daily rhythm of mating with greater sexual activity between the end of the photophase and the first half of the scotophase. During the 7 d of observation, most pairs mated only once, although 30% mated two, three, or four times. In a Y-tube olfactometer, males were attracted by virgin females as well as by the volatile compounds emitted by females. Neither males nor their volatiles were attractive to either sex. Our observation provide information about mating behavior of D. speciosa, which will be useful in future research in chemical communication, such as identification of the pheromone and development of management techniques for this species using pheromone traps. PMID:22732614

Nardi, C; Luvizotto, R A; Parra, J R P; Bento, J M S

2012-06-01

132

Size-assortative mating in Drosophila malerkotliana  

Science.gov (United States)

The relationships between wing size, locomotor activity, mating latency, courtship pattern and mating success (total number of pairs mated in a given time unit) were studied in pairs of Drosophila malerkotlianaMating latency was negatively correlated with wing length and with locomotor activity while wing length and locomotor activity were positively related. In trios of a female and a long-winged and a short-winged male, long-winged males mated more successfully than short-winged males. In trios of a male and a long-winged and a short-winged female, long-winged males mated with long-winged females, and short-winged males with short-winged females. In addition, in pairs of long-winged/short-winged flies, long-winged flies courted and mated more successfully than short-winged flies. PMID:9268474

Hegde; Krishna

1997-08-01

133

Polyandrous females discriminate against previous mates.  

Science.gov (United States)

In most animal species, particularly those in which females engage in polyandry, mate choice is a sequential process in which a female must choose to mate or not to mate with each male encountered. Although a number of theoretical and empirical investigations have examined the effects of sequential mate choice on the operation of sexual selection, how females respond to solicitation by previous mates has received little attention. Here, we report the results of a study carried out on the polyandrous pseudoscorpion, Cordylochernes scorpioides, that assessed the sexual receptivity of once-mated females presented after a lapse of 1.5 hr or 48 hr with either their first mate or a different male. Females exhibited a high level of receptivity to new males, irrespective of intermating interval. By contrast, time between matings exerted a strong effect on female receptivity to previous mates. After a lapse of 48 hr, females did not differ significantly in their receptivity toward previous mates and different males, whereas at 1.5 hr after first mating, females were almost invariably unreceptive to males from whom they had previously accepted sperm. This result could not be attributed to male size or mating experience or to male sexual receptivity. Indeed, males were as willing to transfer sperm to a previous mate as they were to a new female. This difference between males and females in their propensity to remate with the same individual may reflect a conflict between the sexes, with males seeking to minimize postcopulatory sexual selection and females actively keeping open the opportunity for sperm competition and female choice of sperm by discriminating against previous mates. PMID:9811869

Zeh, J A; Newcomer, S D; Zeh, D W

1998-11-10

134

Female-borne cues affecting Psyttalia concolor (Hymenoptera: Braconidae) male behavior during courtship and mating.  

Science.gov (United States)

Knowledge of the mechanisms that regulate courtship and mating behavior in Psyttalia concolor (Szépligeti)-a koinobiont endophagous solitary parasitoid of the olive fruit fly, Bactrocera oleae (Rossi), and of other fruit flies-is essential to its mass rearing and management. Augmentative releases of P. concolor for olive fruit fly control started in the Mediterranean areas in the 1950s and still continue with limited success. We determined the influence of visual and chemical cues on courtship and mating behavior of this braconid and the possible effect of the mating status of males and females in the perception of these cues. Our results suggest that integration of visual and chemical stimuli are fundamental for mate location and courtship. Indeed, the optimal response of the male was achieved when physical and chemical cues were simultaneously presented and vision and olfaction worked synergistically. PMID:23955889

Canale, Angelo; Benelli, Giovanni; Lucchi, Andrea

2013-06-01

135

Females use self-referent cues to avoid mating with previous mates.  

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Females of many species mate repeatedly throughout their lives, often with many different males (polyandry). Females can secure genetic benefits by maximizing their diversity of mating partners, and might be expected, therefore, to forego matings with previous partners in favour of novel males. Indeed, a female preference for novel mating partners has been shown in several taxa, but the mechanism by which females distinguish between novel males and previous mates remains unknown. We show that female crickets (Gryllodes sigillatus) mark males with their own unique chemical signatures during mating, enabling females to recognize prior mates in subsequent encounters and to avoid remating with them. Because self-referent chemosensory cues provide females with a simple, but reliable mechanism of identifying individuals with whom they have mated without requiring any special cognitive ability, they may be a widespread means by which females across a broad range of animal mating systems maximize the genetic benefits of polyandry. PMID:16271971

Ivy, Tracie M; Weddle, Carie B; Sakaluk, Scott K

2005-12-01

136

Individual differences in mate poaching: an examination of hormonal, dispositional, and behavioral mate-value traits.  

Science.gov (United States)

The personality and hormonal correlates of mate poaching (attempting to steal another person's partner away) and of the target of the seducer (the mate poached) were examined in a sample 154 undergraduate university students (91 females; 63 males). Thirteen variables were modeled into two regression equations to predict and profile mate poachers and the mate poached. Findings revealed that (1) male mate poachers were better looking and had higher cortisol levels, lower levels of testosterone, and reported being higher on self-esteem, cold affect, and criminal tendencies and (2) female mate poachers and targets of mate poachers reported being more physically attractive, as did male targets of mate poachers. Sex differences in the context of mate poaching attraction as well as the characteristics of those who are successful in their attempts to lure away another person's romantic partner were discussed. PMID:22695642

Sunderani, Shafik; Arnocky, Steven; Vaillancourt, Tracy

2013-05-01

137

Mate attraction, retention and expulsion.  

Science.gov (United States)

Sexual selection theory and parental investment theory have guided much of the evolutionary psychological research on human mating. Based on these theories, researchers have predicted and found sex differences in mating preferences and behaviors. Men generally prefer that their long-term partners are youthful and physically attractive. Women generally prefer that their long-term partners have existing resources or clear potential for securing resources and display a willingness to invest those resources in children the relationship might produce. Both men and women, however, desire long-term partners who are kind and intelligent. Once a partner is obtained, men and women act in sex-specific ways to ensure the continuation and exclusivity of the relationship. Men, in particular, engage in behaviors designed to prevent, correct, and anticipate their partner's sexual infidelity. Relationships dissolve for evolutionarily-relevant reasons: infidelity, childlessness, and infertility. The discussion addresses directions for future research. PMID:20100421

Miner, Emily J; Shackelford, Todd K

2010-02-01

138

2012 International MATE ROV Competition  

Science.gov (United States)

This video, created by the Marine Advanced Technology Education Center, shares highlights of the 2012 International MATE ROV competition, which was held in Orlando, Florida. 55 teams participated in the competition, which aims to get students interested in science, technology, engineering and math (STEM). Teams constructed their own ROVs and also integrated their own control systems in the competition. Running time for the video is 8:57.

2013-07-18

139

Nutritional enrichment increases courtship intensity and improves mating success in male spiders  

DEFF Research Database (Denmark)

The development of male sexual ornaments and the intensity of male courtship behavior are often used by females as criteria for mate choice and by other males to evaluate the strength of a rival. We tested the hypotheses that courtship intensity and mating success depend on the males' nutritional status (enriched or deficient) and that courtship intensity predicts mating success in males of the same nutritional status. We used wolf spiders, Pardosa prativaga, which have an elaborate display of courtship behaviors, including encircling, palp vibrations, abdomen vibrations, hopping, etc. Viability parameters indicated enhanced condition of enriched males. Mating success was higher for nutrient-enriched males in direct competition with deficient males. Enriched males had higher courtship intensity and were also larger (carapace width) but not heavier than deficient males. The statistical analysis indicated that diet effects on courtship intensity were indirect, through its effect on size. In competition tests between males of equal mass and the same diet treatment, the previously most active male (high levels of palp vibrating, abdomen vibrating, and hopping) had the highest mating success, though this result depended on male nutrient status. The widely used residual condition index (RCI) did not distinguish the treatments. It is suggested that the index is unsuitable in a situation of nutritional stress caused by nutrient imbalance. The results underscore the importance of nutrient balancing to all aspects of performance also in predatory animals.

Lomborg, Johannes Peter; Toft, SØren

2009-01-01

140

Pairomics, the omics way to mate choice.  

Science.gov (United States)

The core aspects of the biology and evolution of sexual reproduction are reviewed with a focus on the diploid, sexually reproducing, outbreeding, polymorphic, unspecialized, altricial and cultural human species. Human mate choice and pair bonding are viewed as central to individuals' lives and to the evolution of the species, and genetic assistance in reproduction is viewed as a universal human right. Pairomics is defined as an emerging branch of the omics science devoted to the study of mate choice at the genomic level and its consequences for present and future generations. In pairomics, comprehensive genetic information of individual genomes is stored in a database. Computational tools are employed to analyze the mating schemes and rules that govern mating among the members of the database. Mating models and algorithms simulate the outcomes of mating any given genome with each of a number of genomes represented in the database. The analyses and simulations may help to understand mating schemes and their outcomes, and also contribute a new cue to the multicued schemes of mate choice. The scientific, medical, evolutionary, ethical, legal and social implications of pairomics are far reaching. The use of genetic information as a search tool in mate choice may influence our health, lifestyle, behavior and culture. As knowledge on genomics, population genetics and gene-environment interactions, as well as the size of genomic databases expand, so does the ability of pairomics to investigate and predict the consequences of mate choice for the present and future generations. PMID:23945982

Dani, Sergio Ulhoa; März, Winfried; Neves, Paulo Mauricio Serrano; Walter, Gerhard Franz

2013-10-01

 
 
 
 
141

Mating duration and sperm precedence in the spider Linyphia triangularis  

DEFF Research Database (Denmark)

In many animal species, mating behaviour is highly ritualised, which may allow us to relate some of its consequences, e.g. male paternity and female receptivity, to the progression of phases in the mating sequence; at the same time, ritualisation raises the question of to what extent the partners, especially the males, are able to influence the outcome of mating for their own benefit. We studied the linyphiid spider Linyphia triangularis in which mating follows a strict sequence during which the male inducts two droplets of sperm and transfers them to the female. We performed sperm competition experiments (sterile-male technique) including four treatments, in which the copulation of the first male was interrupted at prescribed phases of the mating sequence, while the second male was allowed a complete mating. Second males spent a shorter time than first males on the behaviours prior to sperm transfer, but the amount of sperm (2 droplets) and the time spent in sperm transfer were independent of the females’ mating status. The proportion of females accepting the second male depended on the mating duration of the first male, i.e. whether the first male had transferred one or two sperm droplets. After a complete first mating, most females accepted no further males. A last-male sperm precedence was apparent if only half of the first sperm droplet had been transferred by the first male, but this switched to a first male precedence if one full sperm droplet had been transferred. Thus, even in the face of sperm competition, it is sufficient for the first male to transfer one sperm droplet. The second sperm droplet and the extended copulatory courtship associated with its transfer may serve to induce a lack of receptivity in the female, but the males seem unable to enhance their reproductive success through variable copulatory tactics.

Weldingh, Ditte L.; Toft, SØren

2011-01-01

142

Mating order-dependent female mate choice in the polygynandrous common lizard Lacerta vivipara.  

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Recent studies indicate that directional female mate choice and order-dependent female mate choice importantly contribute to non-random mating patterns. In species where females prefer larger sized males, disentangling different hypotheses leading to non-random mating patterns is especially difficult, given that male size usually correlates with behaviours that may lead to non-random mating (e.g. size-dependent emergence from hibernation, male fighting ability). Here we investigate female mate choice and order-dependent female mate choice in the polygynandrous common lizard (Lacerta vivipara). By sequentially presenting males in random order to females, we exclude non-random mating patterns potentially arising due to intra-sexual selection (e.g. male-male competition), trait-dependent encounter probabilities, trait-dependent conspicuousness, or trait-dependent emergence from hibernation. To test for order-dependent female mate choice we investigate whether the previous mating history affects female choice. We show that body size and body condition of the male with which a female mated for the first time were bigger and better, respectively, than the average body size and body condition of the rejected males. There was a negative correlation between body sizes of first and second copulating males. This indicates that female mate choice is dependent on the previous mating history and it shows that the female's choice criteria are non-static, i.e. non-directional. Our study therefore suggests that context-dependent female mate choice may not only arise due to genotype-environment interactions, but also due to other female mating strategies, i.e. order-dependent mate choice. Thus context-dependent female mate choice might be more frequent than previously thought. PMID:19779935

Fitze, Patrick S; Cote, Julien; Clobert, Jean

2010-02-01

143

Covariation and repeatability of male mating effort and mating preferences in a promiscuous fish.  

Science.gov (United States)

Although mate choice by males does occur in nature, our understanding of its importance in driving evolutionary change remains limited compared with that for female mate choice. Recent theoretical models have shown that the evolution of male mate choice is more likely when individual variation in male mating effort and mating preferences exist and positively covary within populations. However, relatively little is known about the nature of such variation and its maintenance within natural populations. Here, using the Trinidadian guppy (Poecilia reticulata) as a model study system, we report that mating effort and mating preferences in males, based on female body length (a strong correlate of fecundity), positively covary and are significantly variable among subjects. Individual males are thus consistent, but not unanimous, in their mate choice. Both individual mating effort (including courtship effort) and mating preference were significantly repeatable. These novel findings support the assumptions and predictions of recent evolutionary models of male mate choice, and are consistent with the presence of additive genetic variation for male mate choice based on female size in our study population and thus with the opportunity for selection and further evolution of large female body size through male mate choice. PMID:23919148

Godin, Jean-Guy J; Auld, Heather L

2013-07-01

144

Gender differences in mate selection preferences: a test of the parental investment model.  

Science.gov (United States)

Evolutionary-related hypotheses about gender differences in mate selection preferences were derived from Triver's parental investment model, which contends that women are more likely than men to seek a mate who possesses nonphysical characteristics that maximize the survival or reproductive prospects of their offspring, and were examined in a meta-analysis of mate selection research (questionnaire studies, analyses of personal advertisements). As predicted, women accorded more weight than men to socioeconomic status, ambitiousness, character, and intelligence, and the largest gender differences were observed for cues to resource acquisition (status, ambitiousness). Also as predicted, gender differences were not found in preferences for characteristics unrelated to progeny survival (sense of humor, "personality"). Where valid comparisons could be made, the findings were generally invariant across generations, cultures, and research paradigms. PMID:1388281

Feingold, A

1992-07-01

145

MATE: The multi-agent test environment  

Science.gov (United States)

In this report we present the Multi-Agent Test Environment, MATE. MATE is a collection of experiment management tools for assisting in the design, testing, and evaluation of distributed problem-solvers. It provides the experimenter with an automated tool for executing and monitoring experiments choosing among rule bases, number of agents, communication strategies, and inference engines. Using MATE the experimenter can run a series of distributed problem-solving experiments without human intervention.

Mason, Cindy L.

1992-01-01

146

The shape of female mating?preferences  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The “shape” of a female mating preference is the relationship between a male trait and the probability of acceptance as a mating partner. The shape of preferences is important in many models of sexual selection, mate recognition, communication, and speciation, yet it has rarely been measured precisely. Here I examine preference shape for male calling song in a bushcricket (katydid). Preferences change dramatically between races of a species, from strongly direction...

Ritchie, Michael?G

1996-01-01

147

Perspective: matching, mate choice, and speciation.  

Science.gov (United States)

Matching was developed in the 1960s to match such entities as residents and hospitals, colleges and students, or employers and employees. This approach is based on "preference lists," whereby each participant ranks potential partners according to his/her preferences and tries to match with the highest-ranking partner available. Here, we discuss the implications of matching for the study of mate choice and speciation. Matching differs from classic approaches in several respects, most notably because under this theoretical framework, the formation of mating pairs is context-dependant (i.e., it depends on the configuration of pairings in the entire population), because the stability of mating pairs is considered explicitly, and because mate choice is mutual. The use of matching to study mate choice and speciation is not merely a theoretical curiosity; its application can generate counter-intuitive predictions and lead to conclusions that differ fundamentally from classic theories about sexual selection and speciation. For example, it predicts that when mate choice is mutual and the stability of mating pairs is critical for successful reproduction, sympatric speciation is a robust evolutionary outcome. Yet the application of matching to the study of mate choice and speciation has been largely dominated by theoretical studies. We present the hamlets, a group of brightly colored Caribbean coral reef fishes in the genus Hypoplectrus (Serranidae), as a particularly apt system to test empirically specific predictions generated by the application of matching to mate choice and speciation. PMID:21624930

Puebla, O; Bermingham, E; Guichard, F

2011-09-01

148

Effect of irradiation on mating ability in the male sweetpotato weevil (Coleoptera: Curculionidae).  

Science.gov (United States)

The sterile insect technique (SIT) is widely used for suppressing or eradicating target pest insect populations. The effectiveness of SIT depends on the ability of released sterile males to mate with and inseminate wild females. Irradiation is the effective manner to sterilize mass-reared insects. The negative impacts of this procedure are not limited to damage on reproductive cells. Gamma-radiation damages the epithelial tissue of midgut, which affects the alimentation in insects. Irradiated males alter their mating behavior over time because of the depression of metabolic activity by sterilization. In this study, we evaluated the male mating performance and sexually compatibility of irradiated male Cylas formicarius elegantulus (Summers) (Coleoptera: Curculionidae) with a 200-Gy dose, as currently used in the SIT program in Okinawa Prefecture, throughout 16 d after irradiation in the laboratory. The mating ability of irradiated males did not differ from that of control males for about a week. However, the mating ability of irradiated male drastically decreased thereafter. We consider that irradiated male C. formicarius elegantulus with a 200-Gy dose had no major effect on male mating behavior approximately for a week after irradiation. PMID:18767728

Kumano, N; Haraguchi, D; Kohama, T

2008-08-01

149

Women who kill their mates.  

Science.gov (United States)

Spousal homicide perpetrators are much more likely to be men than women. Accordingly, little research has focused on delineating characteristics of women who have committed spousal homicide. A retrospective clinical review of coroners' files containing all cases of spousal homicide occurring in Quebec over a 20-year period was carried out. A total of 276 spousal homicides occurred between 1991 and 2010, with 42 homicides by female spouses and 234 homicides by male spouses. Differences between homicides committed by female offenders and male offenders are discussed, and findings on spousal homicide committed by women are compared with those of previous studies. Findings regarding offenses perpetrated by females in the context of mental illness, domestic violence, and homicide-suicide are explored. The finding that only 28% of the female offenders in the Quebec sample had previously been subjected to violence by their victim is in contrast to the popular belief and reports that indicate that most female-perpetrated spousal homicide occurs in self-defense or in reaction to long-term abuse. In fact, women rarely gave a warning before killing their mates. Most did not suffer from a mental illness, although one-fifth were acutely intoxicated at the time of the killing. In the vast majority of cases of women who killed their mates, there were very few indicators that might have signaled the risk and helped predict the violent lethal behavior. PMID:23015414

Bourget, Dominique; Gagné, Pierre

2012-01-01

150

An experimental test of condition-dependent male and female mate choice in zebra finches.  

Science.gov (United States)

In mating systems with social monogamy and obligatory bi-parental care, such as found in many songbird species, male and female fitness depends on the combined parental investment. Hence, both sexes should gain from choosing mates in high rather than low condition. However, theory also predicts that an individual's phenotypic quality can constrain choice, if low condition individuals cannot afford prolonged search efforts and/or face higher risk of rejection. In systems with mutual mate choice, the interaction between male and female condition should thus be a better predictor of choice than either factor in isolation. To address this prediction experimentally, we manipulated male and female condition and subsequently tested male and female mating preferences in zebra finches Taeniopygia guttata, a songbird species with mutual mate choice and obligatory bi-parental care. We experimentally altered phenotypic quality by manipulating the brood size in which the birds were reared. Patterns of association for high- or low-condition individuals of the opposite sex differed for male and female focal birds when tested in an 8-way choice arena. Females showed repeatable condition-assortative preferences for males matching their own rearing background. Male preferences were also repeatable, but not predicted by their own or females' rearing background. In combination with a brief review of the literature on condition-dependent mate choice in the zebra finch we discuss whether the observed sex differences and between-studies differences arise because males and females differ in context sensitivity (e.g. male-male competition suppressing male mating preferences), sampling strategies or susceptibility to rearing conditions (e.g. sex-specific effect on physiology). While a picture emerges that juvenile and current state indeed affect preferences, the development and context-dependency of mutual state-dependent mate choice warrants further study. PMID:21901147

Holveck, Marie-Jeanne; Geberzahn, Nicole; Riebel, Katharina

2011-01-01

151

Glycerol-3-phosphate dehydrogenase expression and oxygen consumption in liver mitochondria of female and male rats with chronic alteration of thyroid status.  

Science.gov (United States)

In our chronic experiments (over several months), the activity and protein amount of glycerol-3-phosphate dehydrogenase (GPDH) in mitochondria isolated from the liver of adult male and female inbred Lewis strain euthyroid (EU), hyperthyroid (TH), and hypothyroid (HY) rats were analyzed by biochemical and Western blot methods. The TH status was induced by intraperitoneal injections of 3,3',5-triiodo- L-thyronine and the HY status with 0.05% solution of methimazole in drinking water. The TH status led to a significant increase and the HY status to a significant decrease of enzyme activity and protein amount in both male and female animals. These changes were, however, more pronounced in females. The EU and TH female rats also showed a significantly higher activity and the TH female rats showed also a significantly higher enzyme amount in comparison with males, while the HY rats showed low levels in both sexes. The glycerol-3-phosphate-dependent oxygen consumption of freshly isolated rat liver mitochondria from the TH animals was higher in comparison with the EU animals and it was activated by idebenone, a synthetic analogue of coenzyme Q, in both the EU and TH rats. Measurements of serum thyroid hormone levels and analysis of anatomical parameters (relative heart and thyroid gland weights) confirmed that our procedures inducing the TH and HY states are efficient and reliable and that determination of GPDH can serve as an additional criterion for the evaluation of the thyroid hormone status. PMID:20886417

Rauchová, H; Mrácek, T; Novák, P; Vokurková, M; Soukup, T

2011-01-01

152

Molecular Mating Type Assay for Fusarium circinatum  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A rapid and reliable mating type assay for Fusarium circinatum was created by applying primers specific for the MAT1-1 and MAT1-2 mating type alleles to genomic DNA in a single PCR. A similar approach may be applied to fungi not previously shown to reproduce sexually, thus enabling studies of population structure and inheritance.

Wallace, M. Margaret; Covert, Sarah F.

2000-01-01

153

Flexible coiled spline securely joins mating cylinders  

Science.gov (United States)

Mating cylindrical members are joined by spline to form an integral structure. The spline is made of tightly coiled, high tensile-strength steel spiral wire that fits a groove between the mating members. It provides a continuous bearing surface for axial thrust between the members.

Coppernol, R. W.

1966-01-01

154

46 CFR 15.810 - Mates.  

Science.gov (United States)

...minimum number of mariners holding a license or MMC officer endorsement as mate required...over must hold an appropriate license or MMC authorizing service as mate. (d...5) of this part or hold a license or MMC authorizing service as either—...

2010-10-01

155

Molecular mating type assay for Fusarium circinatum.  

Science.gov (United States)

A rapid and reliable mating type assay for Fusarium circinatum was created by applying primers specific for the MAT1-1 and MAT1-2 mating type alleles to genomic DNA in a single PCR. A similar approach may be applied to fungi not previously shown to reproduce sexually, thus enabling studies of population structure and inheritance. PMID:11097938

Wallace, M M; Covert, S F

2000-12-01

156

Machinist's Mate J 1 and C: Aviation.  

Science.gov (United States)

The rate training manual is one of a series of training manuals prepared for enlisted personnel of the Navy and Naval Reserve studying for advancement from the Aviation Machinist's Mate ADJ2 rating to ADJ1 to ADJC. Aviation Machinist's Mates J maintain aircraft jet engines and their related systems. Chpater 1 discusses the enlisted rating…

Naval Training Publications Center, Memphis, TN.

157

Genetically Engineered Transvestites Reveal Novel Mating Genes in Budding Yeast  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Haploid budding yeast has two mating types, defined by the alleles of the MAT locus, MATa and MAT?. Two haploid cells of opposite mating types mate by signaling to each other using reciprocal pheromones and receptors, polarizing and growing towards each other, and eventually fusing to form a single diploid cell. The pheromones and receptors are necessary and sufficient to define a mating type, but other mating type-specific proteins make mating more efficient. We examined the role of these p...

Huberman, Lori Bromer; Murray, Andrew W.

2013-01-01

158

Acid phosphatase activity in mating type I and mating type II cell lines of Paramecium primaurelia.  

Science.gov (United States)

The cellular acid phosphatase content, a marker enzyme for lysosomal activity, in Paramecium primaurelia mating type I and mating type II cells was determined by optical laser scanning microscopy. The naphthol AS-TR phosphatase-hexazotized pararosaniline method was used to visualize acid phosphatase activity by the light microscopy. Cell lines of both mating types were tested during culture life, from the early log phase to the death phase. The amount of acid phosphatase was higher in mating type II than in mating type I until the onset of the stationary phase, and then the values reversed. Indeed, during the log phase of growth, mating type II cells formed a higher number of food vacuoles, so that, by taking up a higher amount of bacteria, they sooner became deprived of food. It is suggested that, by lacking nutrients, their synthesis activities and acid phosphatase content were reduced as compared with mating type I cells. PMID:7549019

Ramoino, P; Beltrame, F; Fato, M; Marcenaro, G

1995-01-01

159

The mating game: do opposites really attract?  

Science.gov (United States)

When selecting a mate, females of many species face a complicated decision: choosing a very closely related mate will lead to inbreeding, while choosing a mate who is too genetically dissimilar risks breaking up beneficial gene complexes or local genetic adaptations. To ensure the best genetic quality of their offspring, the perfect compromise lies somewhere in between: an optimally genetically dissimilar partner. Empirical evidence demonstrating female preference for genetically dissimilar mates is proof of the adage 'opposites attract'. In stark contrast, Chandler & Zamudio (2008) show in this issue of Molecular Ecology that female spotted salamanders often choose males that are genetically more similar to themselves (although not if the males are small). Along with other recent work, these field studies highlight the broad spectrum of options available to females with respect to relatedness in their choice of mate that belies this rule of thumb. PMID:18266628

Gow, Jennifer L

2008-03-01

160

The mating behavior of Iguana iguana  

Science.gov (United States)

Over a 19 month period I observed the social behaviors of individually recognized green iguanas, Iguana iguana, at three sites in the llanos of Venezuela. The behavior of iguanas outside the mating season differed from that seen during the mating season in three major ways: (1) during normal waking hours outside the breeding season, adult iguanas spent the majority of time immobile, apparently resting; (2) their interactions involved fewer high intensity displays; and (3) their day to day movements were often nomadic. During the mating season, one site was watched continuously during daylight hours (iguanas sleep throughout the night), allowing a complete count of all copulation attempts (N = 250) and territorial interactions. At all sites, dominant males controlled access to small mating territories. Within the territories there did not appear to be any resources needed by females or their offspring. Thus, females could choose mates directly on the basis of male phenotype. Females aggregated in the mating territories of the largest males and mated preferentially with them. Territorial males copulated only once per day, although on several occasions more than one resident female was receptive on the same day. A few small nonterritorial males exhibited pseudofemale behavior (i.e., they abstained from sexual competition), but most nonterritorial males stayed on the periphery of mating territories and attempted to force copulations on unguarded females (peripheral male behavior). Uncooperative females were mounted by as many as three males simultaneously. Females resisted 95% of the 200 observed mating attempts by peripheral males, but only 56% of the attempts by territorial males (N = 43). The selectivity of the females probably increased the genetic representation of the territorial males in the next generation. During the mating season females maintained a dominance hierarchy among themselves. Low ranked females tended to be excluded from preferred mating territories. In this system, both sexes may be subjected to sexual selection. I hypothesize that the ecological factors responsible for the unusual mating system are related to the lack of defendable resources, the iguana's folivory, and the high density of iguanas present in preferred mating areas.

Rodda, G.H.

1992-01-01

 
 
 
 
161

Using a whole farm model to determine the impacts of mating management on the profitability of pasture-based dairy farms.  

Science.gov (United States)

An approach to assessing likely impacts of altering reproductive performance on productivity and profitability in pasture-based dairy farms is described. The basis is the development of a whole farm model (WFM) that simulates the entire farm system and holistically links multiple physical performance factors to profitability. The WFM consists of a framework that links a mechanistic cow model, a pasture model, a crop model, management policies and climate. It simulates individual cows and paddocks, and runs on a day time-step. The WFM was upgraded to include reproductive modeling capability using reference tables and empirical equations describing published relationships between cow factors, physiology and mating management. It predicts reproductive status at any time point for individual cows within a modeled herd. The performance of six commercial pasture-based dairy farms was simulated for the period of 12 months beginning 1 June 2005 (05/06 year) to evaluate the accuracy of the model by comparison with actual outcomes. The model predicted most key performance indicators within an acceptable range of error (residual<10% of observed). The evaluated WFM was then used for the six farms to estimate the profitability of changes in farm "set-up" (farm conditions at the start of the farming year on 1 June) and mating management from 05/06 to 06/07 year. Among the six farms simulated, the 4-week calving rate emerged as an important set-up factor influencing profitability, while reproductive performance during natural bull mating was identified as an area with the greatest opportunity for improvement. The WFM presents utility to explore alternative management strategies to predict likely outcomes to proposed changes to a pasture-based farm system. PMID:20510554

Beukes, P C; Burke, C R; Levy, G; Tiddy, R M

2010-08-01

162

Podisus nigrispinus requer cópulas longas para o sucesso reprodutivo / Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae) requires long matings for successful reproduction  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A realização de múltiplas e longas cópulas parece ser importante para a reprodução de percevejos predadores como Podisus nigrispinus (Dallas), mas o comportamento governando essas características permanece desconhecido. Neste estudo foram investigados o comportamento de cópula e a reprodução de P. n [...] igrispinus em função do tamanho do macho, seu status prévio de acasalamento, risco de predação e interrupção de cópulas. A escolha da fêmea para o acasalamento foi estudada sob múltipla escolha, parcial ou sem chance de escolha por machos grandes ou pequenos. O comportamento para o início do acasalamento e tempo de cópula sob risco de predação quando na presença de Polistes versicolor Oliver foi comparado àquele de casais sem risco de predação. Machos e fêmeas de P. nigrispinus acasalaram independentemente do tamanho e status prévio de acasalamento dos machos, além de não apresentarem preferência por parceiros. A duração da cópula, escolha do parceiro e fertilidade das fêmeas não foram influenciadas pelo tamanho do macho, nem a presença do predador alterou o comportamento de acasalamento e duração de cópula. Fêmeas com cópulas interrompidas após 30, 60, 120 e 240 min apresentaram baixa viabilidade de ovos (0; 3,1; 7,7 e 34%, respectivamente), enquanto aquelas com tempo natural de cópula (338 a 671 min) obtiveram 74,2% de viabilidade. Portanto, o sucesso reprodutivo de P. nigrispinus não depende do tamanho do macho ou de seu status de acasalamento, mas requer longas cópulas para a transferência de espermatozóides. Abstract in english The occurrence of multiple and long matings seem to play an important role in the reproduction of the predatory stinkbugs such as Podisus nigrispinus (Dallas). However, the mechanisms underlying these behaviors remain unclear. In this study, the reproduction of P. nigrispinus was investigated as fun [...] ction of females' choice for their mating pair based on male body size and previous mating status, risk of predation and duration of mating. The female mating behavior was studied with female having multiple, partial or no partner choice based on male body size. Time to initiate a mating and its duration was observed after pairing males and females under risk of predation imposed by the presence of the predatory wasp Polistes versicolor Oliver. In addition, aiming to determine the reasons for long lasting matings, female had their mating interrupted at different intervals. Our data indicated that P. nigrispinus females do not select male partners as function of their body size and mating status. Duration of mating, mating partners' choice, and female fecundity and fertility were not influenced by the male size and risk of predation imposed by the predatory wasps. Mating interrupted after 30, 60, 120 and 240 min resulted in only 0, 3.1, 7.7 and 34% of egg hatching compared to 74.2% under uninterrupted mating (338 to 671 min long). Therefore, the reproductive success of P. nigrispinus females does not depend on male size and male mating status, but requires long-lasting mating as a condition for adequate spermatozoa transference to females instead.

Agna R S, Rodrigues; Jorge B, Torres; Herbert A A, Siqueira; Valéria W, Teixeira.

2009-12-01

163

Gasket Assembly for Sealing Mating Surfaces  

Science.gov (United States)

A pair of substantially opposed mating surfaces are joined to each other and sealed in place by means of an electrically-conductive member which is placed in proximity to the mating surfaces. The electrically-conductive member has at least one element secured thereto which is positioned to contact the mating surfaces, and which softens when the electrically-conductive member is heated by passing an electric current therethrough. The softened element conforms to the mating surfaces, and upon cooling of the softened element the mating surfaces are joined together in an effective seal. Of particular significance is an embodiment of the electrically-conductive member which is a gasket having an electrically-conductive gasket base and a pair of the elements secured to opposite sides of the gasket base. This embodiment is positioned between the opposed mating surfaces to be joined to each other. Also significant is an embodiment of the electrically-conductive member which is an electrically-conductive sleeve having an element secured to its inner surface. This embodiment surrounds cylindrical members the bases of which are the substantially opposed mating surfaces to be joined, and the element on the inner surface of the sleeve contacts the outer surfaces of the cylindrical members.

Bryant, Melvin A., III (Inventor)

2003-01-01

164

The effect of mate removal on dawn singing behaviour in male pied bush chats  

Directory of Open Access Journals (Sweden)

Full Text Available To determine the influence of pairing status on dawn singing behaviour in pied bush chats Saxicola caprata, we conducted mate removal experiments across eight territories. The experiment was divided into three stages: pre-removal (pairs were present on their respective territories, removal (females were experimentally removed, and returned (females were released into the focal pairs’ territories. Dawn bout length, song rate, song complexity, percentage performance time, song perch height, and distance of singing location to territory boundary were measured for each male during each experimental stage. We did not find an effect of mate removal on any dawn song characteristics of male pied bush chats suggesting that the presence or absence of a mate does not influence male dawn singing behaviour. Our findings further suggest that males use dawn chorus to mediate social relationships with neighbouring males to proclaim an established territory [Current Zoology 57 (1: 72–76, 2011].

Vinaya Kumar SETHI, Dinesh BHATT, Amit KUMAR

2011-02-01

165

Associations between body morphology, mating success and mate preferences among Slovak males and females.  

Science.gov (United States)

Human body morphology is thought to be correlated with sexual behaviour and sociosexuality (defined as an increased willingness to engage in sex without commitment) influences the perception of certain cues of physical attractiveness. Based on a sample of Slovak university students, we investigated relationships between 1) male and female mating success and reported body morphology (body mass index, BMI and waist-to-hip ratio, WHR) and 2) mate preference characteristics and mating success. Both males and females reported a similar number of long-term sexual partners and frequency of engaging in extra-pair copulation (EPC). The mating success of both sexes was positively mediated by self-perceived attractiveness. However, female BMI was inversely associated with mating success whereas increasing BMI was positively associated with male mating success (the total number of lifetime sexual partners) as well as with the likelihood of engaging in EPC. Unrestricted sociosexuality positively correlated with direct and indirect benefits from mating and negatively with the religious/political background of a potential mate and with the desire for a home/ children. These results confirm the hypothesis that human body morphology is associated with sexual behaviour and that cues of direct/indirect benefits in a potential mate positively correlate with sociosexuality. PMID:23980387

Prokop, Pavol; Fedor, Peter

2013-01-01

166

Mating experience and juvenile hormone enhance sexual signaling and mating in male Caribbean fruit flies.  

Science.gov (United States)

Young mated male Caribbean fruit flies [Anastrepha suspensa (Loew)] have greater sexual prowess than their virgin counterparts. After mating for the first time, 6- to 7-day-old males released twice as much sex pheromone and acquired another mate in less than half the time required by virgin males of the same age. Mass spectroscopic analysis of extracts of hemolymph from mated and virgin 7-day-old males resulted in identification of juvenile hormone III bisepoxide and juvenile hormone III in a ratio of 2.5:1. Extracts from mated males contained 3-fold more juvenile hormone than did extracts from virgins. Enhancement of sexual signaling, pheromone release, and mating was induced by topical application of juvenile hormone, methoprene, or fenoxycarb. Newly eclosed adult males treated with juvenoids engaged in sexual signaling, released pheromone, and mated at significantly earlier ages than control males. We conclude that juvenile hormone mediated a positive feedback system that imparted a competitive advantage, guaranteeing that males who mated at an early age would out-compete virgins of the same age for mating opportunities. Additionally, the results support the hypothesis that juvenile hormone is a pivotal hormone coordinating the development of sexual signaling and reproductive maturity in these flies. PMID:10706642

Teal, P E; Gomez-Simuta, Y; Proveaux, A T

2000-03-28

167

Methylation status of CpG islands in the promoter region of genes differentially expressed in colonic mucosa from adenoma patients and controls in response to altered vegetable intake.  

Science.gov (United States)

Vegetables may protect against colorectal cancer (CRC) via changes in gene expression involved in anticarcinogenic mechanisms. There is considerable evidence that aberrant DNA methylation plays an important role in carcinogenesis. Furthermore, DNA methylation can be affected by dietary components. Therefore, in the present study, we investigated the DNA methylation status of CpG dinucleotides within the promoter region of the four genes protein kinase C b 1, ornithine decarboxylase 1, fos proto-oncogene and 5,10-methylenetetrahydrofolate reductase in the colon of female sporadic adenoma patients and healthy controls. These genes were chosen because their expression was modulated in response to altered vegetable intake, they are functionally relevant for CRC; they have CpG islands in their promoter region, and a methylation-specific restriction enzyme is available to permit quantitative assay. No significant differences in extent of methylation in colon DNA were detected for any of the four genes in both adenoma polyp patients and healthy controls after altering vegetable intake. Interestingly, before the intervention, ornithine decarboxylase 1 promoter methylation was lower in the colonic mucosa of the adenoma polyp patients when compared with healthy control subjects, which may explain the increased ornithine decarboxylase 1 activity in CRC reported in the literature. In conclusion, we found no evidence that changes in promoter methylation were responsible for differences in expression of four genes in the human colonic mucosa in response to altered vegetable intake. The mechanism(s) responsible for this altered gene expression and, indeed, potential effects on methylation of other genes remain to be determined. PMID:19434801

van Breda, Simone G J; van Delft, Joost H M; Engels, Leopold G J B; Kleinjans, Jos C S; Mathers, John C

2009-05-01

168

Antioxidant activity of polyphenols from green and toasted mate tea.  

Science.gov (United States)

The production and distribution of toasted mate tea in Brazil has increased, which has resulted in its greater consumption. Mate tea is obtained by roasting non-fermented erva-mate in order to produce toasted erva-mate or toasted mate tea. However, although the product is much appreciated, studies of its chemical composition and the concentration of polyphenols, particularly flavonols present in toasted mate tea, are few and often controversial. This paper elucidates some misunderstandings involving the nomenclature of erva-mate and toasted mate, and mainly provides an overview of the composition of polyphenols and antioxidant capacity of toasted mate tea and its raw material, erva-mate, in comparison with other teas, the compositions of which were found in the literature. PMID:21615026

Coentrão, Patricia de Abreu Marques; Teixeira, Valéria Laneuville; Netto, Annibal Duarte Pereira

2011-05-01

169

Reinforcement and divergence under assortative mating.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Traits that cause assortative mating such as the flowering time in plants and body size in animals can produce reproductive isolation between hybridizing populations. Can selection against unfit hybrids cause two populations to diverge in their mean values for these kinds of traits? Here I present a haploid analytical model of one population that receives gene flow from another. The partial pre-zygotic isolation between the two populations is caused by assortative mating for a trait that is i...

Kirkpatrick, M.

2000-01-01

170

Advanced Mating System Development for Space Applications  

Science.gov (United States)

This slide presentation reviews the development of space flight sealing and the work required for the further development of a dynamic interface seal for the use on space mating systems to support a fully androgynous mating interface. This effort has resulted in the advocacy of developing a standard multipurpose interface for use with all modern modular space architecture. This fully androgynous design means a seal-on-seal (SOS) system.

Lewis, James L.

2004-01-01

171

Observing free-swimming copepods mating  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Planktonic copepods are small transparent animals swimming in water. To observe how a male finds its mate, special optical systems had to be designed. The animals are treated as phase objects and matched spatial filters allow three-dimensional recordings of the swimming behaviour in a 1-litre vessel. Application of the techniques described shows how a male cyclopoid copepod swims for 20 s in synchronicity with the female before mating. Results stemming from observations with this optical syst...

Strickler, J. R.

1998-01-01

172

An algorithm for efficient constrained mate selection  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Mate selection can be used as a framework to balance key technical, cost and logistical issues while implementing a breeding program at a tactical level. The resulting mating lists accommodate optimal contributions of parents to future generations, in conjunction with other factors such as progeny inbreeding, connection between herds, use of reproductive technologies, management of the genetic distribution of nominated traits, and management of allele/genotype frequencies for nominated QTL/markers. Methods This paper describes a mate selection algorithm that is widely used and presents an extension that makes it possible to apply constraints on certain matings, as dictated through a group mating permission matrix. Results This full algorithm leads to simpler applications, and to computing speed for the scenario tested, which is several hundred times faster than the previous strategy of penalising solutions that break constraints. Conclusions The much higher speed of the method presented here extends the use of mate selection and enables implementation in relatively large programs across breeding units.

Kinghorn Brian P

2011-01-01

173

In Vivo and In Vitro Anaerobic Mating in Candida albicans?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Candida albicans cells of opposite mating types are thought to conjugate during infection in mammalian hosts, but paradoxically, the mating-competent opaque state is not stable at mammalian body temperatures. We found that anaerobic conditions stabilize the opaque state at 37°C, block production of farnesol, and permit in vitro mating at 37°C at efficiencies of up to 84%. Aerobically, farnesol prevents mating because it kills the opaque cells necessary for mating, and as a corollary, farnes...

Dumitru, Raluca; Navarathna, Dhammika H. M. L. P.; Semighini, Camile P.; Elowsky, Christian G.; Dumitru, Razvan V.; Dignard, Daniel; Whiteway, Malcolm; Atkin, Audrey L.; Nickerson, Kenneth W.

2007-01-01

174

Effect of 60CO radiation processing in mate (Ilex paraguariensis)  

International Nuclear Information System (INIS)

The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from 60Co at doses 0, 3, 5, 7 and 10kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and qualitative profile of bioactive compounds. (author)

175

Effect of 60Co radiation processing in mate (Ilex paraguariensis)  

International Nuclear Information System (INIS)

The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from 60Co at doses 0, 3, 5, 7 and 10 kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10 kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10 kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and qualitative profile of bioactive compounds. (author)

176

Sampling and assessment accuracy in mate choice: A random-walk model of information processing in mating decision  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Mate choice depends on mating preferences and on the manner in which mate-quality information is acquired and used to make decisions. We present a model that describes how these two components of mating decision interact with each other during a comparative evaluation of prospective mates. The model, with its well-explored precedents in psychology and neurophysiology, assumes that decisions are made by the integration over time of noisy information until a stopping-rule cr...

2011-01-01

177

A process of pair formation leading to assortative mating: Passive age-assortative mating by habitat heterogeneity  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We present an individual-based model dealing with mating as a process of pair formation. Model simulations, based on data from a 19-year study of Spanish imperial eagles, Aquila adalberti, showed that the mating pattern of a population is not necessarily a direct consequence of the mating preferences of individuals; positive age-assortative mating, by which individuals of similar age are more likely to become paired, does not necessarily indicate homotypic mating preferences. For example, ind...

Ferrer, Miguel; Penteriani, Vincenzo

2003-01-01

178

Dietary retinoic acid alters vitamin A kinetics in both the whole body and in specific organs of rats with low vitamin A status.  

Science.gov (United States)

To study the effects of exogenous retinoic acid on vitamin A (VA) metabolism, we analyzed previously collected tracer kinetic data on VA dynamics in rats with low vitamin A (LA) status either with (LA+RA) or without (LA) retinoic acid supplementation. In spite of low VA intake ( approximately 7 nmol/d), the LA+RA rats were in a slight positive VA balance (0.325 nmol/d vs. -0.168 for LA) for 35 d after administration of [(3)H]retinol-labeled plasma. Using the Windows version of the Simulation, Analysis and Modeling software, we determined that the VA disposal rate was lower in LA+RA than in LA rats (3.98 vs. 5.00 nmol/d) as was the system fractional catabolic rate (0.0548 vs. 0.110 d(-1)). Model-predicted traced mass and residence times (the average time that a molecule of retinol spends in an organ before irreversible loss) were higher for liver (19.4 vs. 1.8 nmol; 5.0 vs. 0.36 d), kidneys (7.0 vs. 2.1 nmol; 1.4 vs. 0.42 d), small intestine (2.1 vs. 0.42 nmol; 0.43 vs. 0.084 d), and lungs (3.2 vs. 0.10 nmol; 1.6 vs. 0.021 d) in the LA+RA compared with the LA rats; there were no major differences for eyes, testes, adrenal glands, or remaining carcass. We conclude that RA supplementation of rats with low VA status affects VA metabolism at both the whole-body level and in specific organs. These organs (liver, kidneys, small intestine, and lungs) have the enzymatic capability and an appropriate cell type to store retinyl esters. PMID:15795428

Cifelli, Christopher J; Green, Joanne Balmer; Green, Michael H

2005-04-01

179

Prism adaptation does not alter configural processing of faces [v1; ref status: indexed, http://f1000r.es/1wk  

Directory of Open Access Journals (Sweden)

Full Text Available Patients with hemispatial neglect (‘neglect’ following a brain lesion show difficulty responding or orienting to objects and events on the left side of space. Substantial evidence supports the use of a sensorimotor training technique called prism adaptation as a treatment for neglect. Reaching for visual targets viewed through prismatic lenses that induce a rightward shift in the visual image results in a leftward recalibration of reaching movements that is accompanied by a reduction of symptoms in patients with neglect. The understanding of prism adaptation has also been advanced through studies of healthy participants, in whom adaptation to leftward prismatic shifts results in temporary neglect-like performance. Interestingly, prism adaptation can also alter aspects of non-lateralised spatial attention. We previously demonstrated that prism adaptation alters the extent to which neglect patients and healthy participants process local features versus global configurations of visual stimuli. Since deficits in non-lateralised spatial attention are thought to contribute to the severity of neglect symptoms, it is possible that the effect of prism adaptation on these deficits contributes to its efficacy. This study examines the pervasiveness of the effects of prism adaptation on perception by examining the effect of prism adaptation on configural face processing using a composite face task. The composite face task is a persuasive demonstration of the automatic global-level processing of faces: the top and bottom halves of two familiar faces form a seemingly new, unknown face when viewed together. Participants identified the top or bottom halves of composite faces before and after prism adaptation. Sensorimotor adaptation was confirmed by significant pointing aftereffect, however there was no significant change in the extent to which the irrelevant face half interfered with processing. The results support the proposal that the therapeutic effects of prism adaptation are limited to dorsal stream processing.

Janet H. Bultitude

2013-10-01

180

Precopulatory Mate Guarding, Mating System and Pairing Parental Care in Hyale rubra (Peracarida; Amphipoda; Gammaridae  

Directory of Open Access Journals (Sweden)

Full Text Available Mating behaviour of the gammarid amphipod, Hyale rubra, was observed. H. rubra displayedprecopulatory mate guarding: males clasped females with their gnathopods during copulation, forming a pair.Males also participated in embryo care during the incubation period. The population was small, and the sex ratiowas almost equal. Energy allocation for mating effort and parental effort in the two sexes appear to be almostequal. The mating system was sequentially polygamous (or promiscuous and there was conspicuous sexualdimorphism in the size of the gnathopod, which was used for mate guarding. However, there appears to berelatively weak sexual competition for mating opportunities despite conspicuous sexual dimorphism. H. rubra didnot display territorial competition or external fertilization. Nevertheless, the male provided paternal care. SinceH. rubra inhabit tide pools and live on algae, the polygamous mating system of the species can be explainedby the polygyny threshold model. The evolution of mate guarding and parental care may have been favored bythe species’ low population density and harsh environments, an interpretation consistent with the optimalitymodel.

Kim, Sunghan

2008-02-01

 
 
 
 
181

Impact of market value on human mate choice decisions.  

Science.gov (United States)

Mate choice strategies are a process of negotiation in which individuals make bids that are constrained by their status in the market place. Humans provide an unusual perspective on this because we can measure their explicitly expressed preferences before they are forced to make any choices. We use advertisements placed in newspaper personal columns to examine, first, the extent to which evolutionary considerations affect the level of competition (or market value) during the reproductively active period of people's lives and, second, the extent to which market value influences individual's willingness to make strong demands of prospective mates. We show that female market value is determined principally by women's fecundity (and, to a lesser extent, reproductive value), while male market value is determined by men's earning potential and the risk of future pairbond termination (the conjoint probability that the male will either die or divorce his partner during the next 20 years). We then show that these selection preferences strongly influence the levels of demands that men and women make of prospective partners (although older males tend to overestimate their market value). PMID:10081164

Paw?owski, B; Dunbar, R I

1999-02-01

182

Influences of social learning on mate-choice decisions.  

Science.gov (United States)

Evidence from both field and laboratory is consistent with the hypothesis that animals can acquire mate preferences by observing the mating behavior of others. It is difficult, however, to distinguish social learning about mates from a host of other social effects on mating that do not produce changes in preferences. Examples are drawn from laboratory studies on mate choice in female and male Japanese quail that illustrate ways in which social cues influence mating decisions. Quail of both sexes use social cues to modify their mate choices, but the sexes use the information to serve different purposes. Female quail gain preferences for males seen mating with other females, whereas males avoid females that they had observed mating with other males. This sex difference in social learning provides an example of how costs and benefits of sexual behavior can shape decision-making processes. Implications of the influence of social learning on sexual selection are briefly discussed. PMID:15161145

White, David J

2004-02-01

183

Condition-dependent mate choice: A stochastic dynamic programming approach.  

Science.gov (United States)

We study how changing female condition during the mating season and condition-dependent search costs impact female mate choice, and what strategies a female could employ in choosing mates to maximize her own fitness. We address this problem via a stochastic dynamic programming model of mate choice. In the model, a female encounters males sequentially and must choose whether to mate or continue searching. As the female searches, her own condition changes stochastically, and she incurs condition-dependent search costs. The female attempts to maximize the quality of the offspring, which is a function of the female's condition at mating and the quality of the male with whom she mates. The mating strategy that maximizes the female's net expected reward is a quality threshold. We compare the optimal policy with other well-known mate choice strategies, and we use simulations to examine how well the optimal policy fares under imperfect information. PMID:24996205

Frame, Alicia M; Mills, Alex F

2014-09-01

184

Sexual behavior across ovarian cycles in wild black howler monkeys (Alouatta pigra): male mate guarding and female mate choice.  

Science.gov (United States)

We studied two multimale-multifemale groups of black howler monkeys (Alouatta pigra) during a 14-month study (June 2006-July 2007) in Palenque National Park, Mexico to evaluate the ways in which their sexual behavior changes across ovarian cycles. We analyzed 231 fecal samples, collected every 2.2+/-1.4 days from five females. For four females, estradiol and progesterone profiles revealed an average (+/-SE) cycle length of 18.3+/-1.4 days. Copulations occurred significantly more frequently during the periovulatory period (POP), defined as the estimated day of ovulation +/-3 days (N=18). This was largely the result of cycling females soliciting sexual interactions during their POPs. Females directed their solicitations significantly more often toward "central" males of their group, who had close spatial associations with females at other times, compared with "noncentral" males, who did not associate closely with females. Central males rarely solicited sexual interactions, but instead monitored the females' reproductive status by sniffing their genitals, and maintained significantly closer proximity to females during their POPs, suggesting male mate guarding when conceptions are most likely to occur. Our findings indicate that the reproductive strategies of black howler central males and females coincide, highly skewing mating opportunities toward central males. Black howler females, however, occasionally choose to copulate with noncentral resident males or extra-group males during their POPs, undermining the ability of central males to monopolize all reproductive opportunities. PMID:19016487

Van Belle, Sarie; Estrada, Alejandro; Ziegler, Toni E; Strier, Karen B

2009-02-01

185

Fenthion, an organophosphorus pesticide, induces alterations in oxidant/antioxidant status and histopathological disorders in cerebrum and cerebellum of suckling rats.  

Science.gov (United States)

Fenthion (FEN) is an organophosphorus pesticide known for its wide toxic manifestations. In this study, the effects of FEN were evaluated on the cerebrum and cerebellum oxidant/antioxidant status and histopathological disorders in the suckling rats. Pregnant rats were divided into two groups: control group received pure water, while FEN group received daily by their drinking water 551 ppm of FEN from the 14th day of pregnancy until day 14 after delivery. Acetylcholine esterase (AChE) activity was inhibited in both the cerebrum and cerebellum of suckling rats whose mothers were treated with FEN. The cerebrum and cerebellum oxidative damage was demonstrated by a significant increase of malondialdehyde (MDA), advanced oxidation protein product and glutathione (GSH) levels and disturbance in the antioxidant enzyme activities. A significant decline of non-protein thiol and vitamin C levels was also observed. These changes were confirmed by histopathological observations which were marked by pyknotic neurons in the cerebrum and apoptotic cells in the cerebellum of FEN-treated rats. In the cerebellum of FEN-treated rats, the most conspicuous damage was the absence of external granular layer, indicating growth retardation. These data suggested that exposure of pregnant and lactating rats to FEN induced oxidative stress and histopathological disorders in the cerebrum and cerebellum of their pups. Thus, the use of FEN must be under strict control, especially for pregnant and lactating mothers. PMID:25296500

Ben Amara, Ibtissem; Sefi, Mediha; Troudi, Afef; Soudani, Nejla; Boudawara, Tahia; Zeghal, Najiba

2014-08-01

186

Exploration and mating range in African Pygmies.  

Science.gov (United States)

The distributions of exploration range and of mating range were studied among Aka Pygmies of the Central African Republic. Exploration range is defined and methods of estimation for single individuals suggested. A simple exponential distribution is found for individual Aka Pygmies, with variation of exploration range (the parameter defining mobility) with sex, age and ethnic affiliation. Distribution of distances from birthplace and place of residence are compared and show modest differences. The frequency of visits to a given place has also been studied. The average distance between birthplaces of mates is very similar to the mean exploration range. Correlations between individual exploration and mating ranges suggest that it is the male who may be choosing a marriage partner among Pygmies. A theory by Boyce, Küchemann & Harrison (1967) on the relations between "neighbourhood knowledge" and mating distance is inapplicable because of its reliance on the Pareto distribution, which does not apply in the present case, and of other unnecessary assumptions, but the general principle of a close relationship between exploratory activity and mating distance seems valid, at least in the present case. Suggestions are made for causes for the difference between the present distributions and those with other shapes observed in less primitive economies. PMID:7125597

Cavalli-Sforza, L L; Hewlett, B

1982-07-01

187

Husband's esteem predicts his mate retention tactics.  

Science.gov (United States)

Men sometimes enact mate retention tactics to thwart a partner's infidelity or prevent their defection from the relationship. These tactics include low-risk acts that render the current relationship more attractive by bestowing benefits on the woman, as well as cost-inflicting acts that render defection from the relationship risky or dangerous for her. Previous research has linked men's mate retention behavior with men's mate value (value as a current or potential partner) using women's reports. The current research addresses limitations of that research using self-reports and cross-spousal reports from 107 married couples concerning their self-esteem and their esteem for their partner. The results indicate that the level of esteem that wives have for their husbands is positively associated with their perception of their husband's use of positive inducements and negatively associated with their husband's self-reported use of cost-inflicting mate retention behaviors (i.e., Direct Guarding, Intersexual Negative Inducements, and Intrasexual Negative Inducements). The level of self-esteem reported by men was negatively associated with their self-reported direct guarding behavior. Discussion explores the possibility that esteem-both self-esteem and esteem from one's partner-functions as an internal gauge of relative mate value. PMID:25299998

Holden, Christopher J; Shackelford, Todd K; Zeigler-Hill, Virgil; Miner, Emily J; Kaighobadi, Farnaz; Starratt, Valerie G; Jeffery, Austin John; Buss, David M

2014-01-01

188

The effect of novel promoter variants in MATE1 and MATE2 on the pharmacokinetics and pharmacodynamics of metformin.  

Science.gov (United States)

Interindividual variation in response to metformin, first-line therapy for type 2 diabetes, is substantial. Given that transporters are determinants of metformin pharmacokinetics, we examined the effects of promoter variants in both multidrug and toxin extrusion protein 1 (MATE1) (g.-66T ? C, rs2252281) and MATE2 (g.-130G ? A, rs12943590) on variation in metformin disposition and response. The pharmacokinetics and glucose-lowering effects of metformin were assessed in healthy volunteers (n = 57) receiving metformin. The renal and secretory clearances of metformin were higher (22% and 26%, respectively) in carriers of variant MATE2 who were also MATE1 reference (P MATE1 and MATE2 having an enhanced (P MATE1 variant showed enhanced metformin response. These findings suggest that promoter variants of MATE1 and MATE2 are important determinants of metformin disposition and response in healthy volunteers and diabetic patients. PMID:23267855

Stocker, S L; Morrissey, K M; Yee, S W; Castro, R A; Xu, L; Dahlin, A; Ramirez, A H; Roden, D M; Wilke, R A; McCarty, C A; Davis, R L; Brett, C M; Giacomini, K M

2013-02-01

189

Post-mating Gene Expression Profiles of Female Drosophila melanogaster in Response to Time and to Four Male Accessory Gland Proteins  

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In Drosophila melanogaster, the genetic and molecular bases of post-mating changes in the female's behavior and physiology are poorly understood. However, DNA microarray studies have demonstrated that, shortly after mating, transcript abundance of >1700 genes is altered in the female's reproductive tract as well as in other tissues. Many of these changes are elicited by sperm and seminal fluid proteins (Acps) that males transfer to females. To further dissect the transcript-level changes that...

Mcgraw, Lisa A.; Clark, Andrew G.; Wolfner, Mariana F.

2008-01-01

190

Sexual behavior, cannibalism, and mating plugs as sticky traps in the orb weaver spider Leucauge argyra (Tetragnathidae)  

Science.gov (United States)

Unpublished field observations in Leucauge argyra, a tropical orb weaver spider, suggest the occurrence of conspicuous mating plugs that could reduce or prevent remating attempts. Otherwise, the sexual behavior of this species remains unknown. The aims of this study were to describe the courtship behavior and copulation in L. argyra and investigate mating plug formation in this species. Fourteen virgin females and 12 plugged females were exposed to up to three males and checked for mating plug formation. Of the 12 virgins that copulated, nine produced plugs (five immediately after copulation), and the five plugged females that copulated produced another mating plug immediately after copulation. We did not detect the transfer of any male substance during copulation but observed a whitish liquid emerging from female genital ducts. Plug formation was positively associated with male twanging during courtship. One virgin and four plugged females cannibalized males. In seven trials with virgins and in three trials with plugged females, the male's palp adhered to a substance that emerged from female genital ducts and spread on her genital plate. The male had to struggle energetically to free his glued palp; two of these males were cannibalized while trying to release their palps. Females seem to determine copulation duration by altering the timing of mating plug formation and through sexual cannibalism. This is the first case reported of a mating plug as a sticky trap for males.

Aisenberg, Anita; Barrantes, Gilbert

2011-07-01

191

Visual mate choice in poison frogs.  

Science.gov (United States)

We investigated female mate choice on the basis of visual cues in two populations of Dendrobates pumilio, the strawberry poison frog, from the Bocas del Toro Archipelago in Panama, Central America. Mate choice experiments were carried out by presenting subject females of each of two morphs of this species (orange and green) from two different island populations (Nancy Key and Pope Island) with object frogs (one of each morph) under glass at one end of a terrarium. Recorded calls were played simultaneously from behind both object frogs. The experiments were carried out under two light regimes: (i) white light, and (ii) relatively monochromatic filtered blue light. Subject females from each population displayed a significant preference for their own morph under white light, but not under blue light. These results indicate that female D. pumilio use visual cues in mate choice, and suggest that colour may be the visual cue they use. PMID:10649631

Summers, K; Symula, R; Clough, M; Cronin, T

1999-11-01

192

The Medusa Algorithm for Polynomial Matings  

CERN Document Server

The Medusa algorithm takes as input two postcritically finite quadratic polynomials and outputs the quadratic rational map which is the mating of the two polynomials (if it exists). Specifically, the output is a sequence of approximations for the parameters of the rational map, as well as an image of its Julia set. Whether these approximations converge is answered using Thurston's topological characterization of rational maps. This algorithm was designed by John Hamal Hubbard, and implemented in 1998 by Christian Henriksen and REU students David Farris, and Kuon Ju Liu. In this paper we describe the algorithm and its implementation, discuss some output from the program (including many pictures) and related questions. Specifically, we include images and a discussion for some shared matings, Lattes examples, and tuning sequences of matings.

Boyd, Suzanne Hruska

2011-01-01

193

Experience-mediated plasticity in mate preferences: mating assurance in a variable environment.  

Science.gov (United States)

An individual's prior experience of sexual signals can result in variation in mate preferences, with important consequences for the course of sexual selection. We test two hypotheses about the evolution of experience-mediated plasticity in mate preferences: mating assurance and mismating avoidance. We exposed female Enchenopa binotata treehoppers (Hemiptera: Membracidae) to treatments that varied their experience of signal frequency, the most divergent sexual signal trait in the E. binotata species complex. Treatments consisted of (1) signals matching the preferred frequency, (2-3) signals deviating either 100 Hz above or 100 Hz below the preferred frequency, and (4) no signals. Females experiencing preferred signals showed the greatest selectivity. However, experience had no effect on peak preference. These results support the hypothesis that selection has favored plasticity in mate preferences that ensures that mating takes place when preferred mates are rare or absent, while ensuring choice of preferred types when those are present. We consider how experience-mediated plasticity may influence selection on sexual advertisement signals, patterns of reproductive isolation, and the maintenance of genetic variation. We suggest that the plasticity we describe may increase the likelihood of successful colonization of a novel environment, where preferred mating types may be rare. PMID:22276541

Fowler-Finn, Kasey D; Rodríguez, Rafael L

2012-02-01

194

How universal are human mate choices? Size does not matter when Hadza foragers are choosing a mate  

Digital Repository Infrastructure Vision for European Research (DRIVER)

It has been argued that size matters on the human mate market: both stated preferences and mate choices have been found to be non-random with respect to height and weight. But how universal are these patterns? Most of the literature on human mating patterns is based on post-industrial societies. Much less is known about mating behaviour in more traditional societies. Here we investigate mate choice by analysing whether there is any evidence for non-random mating with respect to size and stren...

Sear, R.; Marlowe, F. W.

2009-01-01

195

How universal are human mate choices ? size does not matter when Hadza foragers are choosing a mate.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

It has been argued that size matters on the human mate market: both stated preferences and mate choices have been found to be non-random with respect to height and weight. But how universal are these patterns? Most of the literature on human mating patterns is based on post-industrial societies. Much less is known about mating behaviour in more traditional societies. Here we investigate mate choice by analysing whether there is any evidence for non-random mating with respect to size and stren...

2009-01-01

196

How universal are human mate choices?: size doesn’t matter when Hadza foragers are choosing a mate  

Digital Repository Infrastructure Vision for European Research (DRIVER)

It has been argued that size matters on the human mate market: both stated preferences and mate choices have been found to be non-random with respect to height and weight. But how universal are these patterns? Most of the literature on human mating patterns is based on post-industrial societies. Much less is known about mating behaviour in more traditional societies. Here we investigate mate choice by analysing whether there is any evidence for non-random mating with respect to size and stren...

Sear, Rebecca; Marlowe, Frank W.

2009-01-01

197

Overexpression of miR-146a in basal-like breast cancer cells confers enhanced tumorigenic potential in association with altered p53 status.  

Science.gov (United States)

The tumor suppressor p53 is the most frequently mutated gene in human cancers, mutated in 25-30% of breast cancers. However, mutation rates differ according to breast cancer subtype, being more prevalent in aggressive estrogen receptor-negative tumors and basal-like and HER2-amplified subtypes. This heterogeneity suggests that p53 may function differently across breast cancer subtypes. We used RNAi-mediated p53 knockdown (KD) and antagomir-mediated KD of microRNAs to study how gene expression and cellular response to p53 loss differ in luminal versus basal-like breast cancer. As expected, p53 loss caused downregulation of established p53 targets (e.g. p21 and miR-34 family) and increased proliferation in both luminal and basal-like cell lines. However, some p53-dependent changes were subtype specific, including expression of miR-134, miR-146a and miR-181b. To study the cellular response to miR-146a upregulation in p53-impaired basal-like lines, antagomir KD of miR-146a was performed. KD of miR-146a caused decreased proliferation and increased apoptosis, effectively ablating the effects of p53 loss. Furthermore, we found that miR-146a upregulation decreased NF-?B expression and downregulated the NF-?B-dependent extrinsic apoptotic pathway (including tumor necrosis factor, FADD and TRADD) and antagomir-mediated miR-146a KD restored expression of these components, suggesting a plausible mechanism for miR-146a-dependent cellular responses. These findings are relevant to human basal-like tumor progression in vivo, since miR-146a is highly expressed in p53 mutant basal-like breast cancers. These findings suggest that targeting miR-146a expression may have value for altering the aggressiveness of p53 mutant basal-like tumors. PMID:25123132

Sandhu, Rupninder; Rein, Jessica; D'Arcy, Monica; Herschkowitz, Jason I; Hoadley, Katherine A; Troester, Melissa A

2014-11-01

198

The Pressurized Mating Adapter-2 is prepared for mating to Node 1 in SSPF  

Science.gov (United States)

The Pressurized Mating Adapter (PMA)-2 for the International Space Station (ISS) awaits being mated with Node 1, the space stations structural building block, in KSCs Space Station Processing Facility. This PMA, identifiable by its bright red ring, is a cone-shaped connector to Node 1, which will have two PMAs attached once this mate is completed. The node and PMAs, which together will make up the first element of the ISS, are scheduled to be launched aboard the Space Shuttle Endeavour on STS-88.

1998-01-01

199

Bird mating optimizer: An optimization algorithm inspired by bird mating strategies  

Science.gov (United States)

Thanks to their simplicity and flexibility, evolutionary algorithms (EAs) have attracted significant attention to tackle complex optimization problems. The underlying idea behind all EAs is the same and they differ only in technical details. In this paper, we propose a novel version of EAs, bird mating optimizer (BMO), for continuous optimization problems which is inspired by mating strategies of bird species during mating season. BMO imitates the behavior of bird species metaphorically to breed broods with superior genes for designing optimum searching techniques. On a large set of unimodal and multimodal benchmark functions, BMO represents a competitive performance to other EAs.

Askarzadeh, Alireza

2014-04-01

200

Chemical profiles of two pheromone glands are differentially regulated by distinct mating factors in honey bee queens (Apis mellifera L.).  

Science.gov (United States)

Pheromones mediate social interactions among individuals in a wide variety of species, from yeast to mammals. In social insects such as honey bees, pheromone communication systems can be extraordinarily complex and serve to coordinate behaviors among many individuals. One of the primary mediators of social behavior and organization in honey bee colonies is queen pheromone, which is produced by multiple glands. The types and quantities of chemicals produced differ significantly between virgin and mated queens, and recent studies have suggested that, in newly mated queens, insemination volume or quantity can affect pheromone production. Here, we examine the long-term impact of different factors involved during queen insemination on the chemical composition of the mandibular and Dufour's glands, two of the major sources of queen pheromone. Our results demonstrate that carbon dioxide (an anesthetic used in instrumental insemination), physical manipulation of genital tract (presumably mimicking the act of copulation), insemination substance (saline vs. semen), and insemination volume (1 vs. 8 µl) all have long-term effects on mandibular gland chemical profiles. In contrast, Dufour's gland chemical profiles were changed only upon insemination and were not influenced by exposure to carbon dioxide, manipulation, insemination substance or volume. These results suggest that the chemical contents of these two glands are regulated by different neuro-physiological mechanisms. Furthermore, workers responded differently to the different mandibular gland extracts in a choice assay. Although these studies must be validated in naturally mated queens of varying mating quality, our results suggest that while the chemical composition of Dufour's gland is associated with mating status, that of the mandibular glands is associated with both mating status and insemination success. Thus, the queen appears to be signaling both status and reproductive quality to the workers, which may impact worker behavior and physiology as well as social organization and productivity of the colony. PMID:24236028

Niño, Elina L; Malka, Osnat; Hefetz, Abraham; Tarpy, David R; Grozinger, Christina M

2013-01-01

 
 
 
 
201

Polymyxin B nonapeptide inhibits mating in Saccharomyces cerevisiae.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Polymyxin B nonapeptide enhanced susceptibility of yeast cells to various hydrophobic antibiotics and to mating pheromones. At much lower concentrations, the nonapeptide severely inhibited mating. The inhibition was caused by interference with sexual agglutination.

Boguslawski, G.

1986-01-01

202

Courtship and mating in Heterometrus petersii (Thorell, 1876 (Scorpiones: Scorpionidae.  

Directory of Open Access Journals (Sweden)

Full Text Available Courtship and mating in Heterometrus petersii (Thorell, 1876 (Scorpiones: Scorpionidae was observed in the laboratory. In this paper the behavior components displayed in courtship and mating are identified, analyzed and discussed.

Jiao, Guo-Bin

2009-06-01

203

Courtship and mating in Heterometrus petersii (Thorell, 1876) (Scorpiones: Scorpionidae).  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Courtship and mating in Heterometrus petersii (Thorell, 1876) (Scorpiones: Scorpionidae) was observed in the laboratory. In this paper the behavior components displayed in courtship and mating are identified, analyzed and discussed.

Jiao, Guo-bin; Zhu, Ming-sheng

2009-01-01

204

Heterozygosity-based assortative mating in blue tits (Cyanistes caeruleus): implications for the evolution of mate choice.  

Science.gov (United States)

The general hypothesis of mate choice based on non-additive genetic traits suggests that individuals would gain important benefits by choosing genetically dissimilar mates (compatible mate hypothesis) and/or more heterozygous mates (heterozygous mate hypothesis). In this study, we test these hypotheses in a socially monogamous bird, the blue tit (Cyanistes caeruleus). We found no evidence for a relatedness-based mating pattern, but heterozygosity was positively correlated between social mates, suggesting that blue tits may base their mating preferences on partner's heterozygosity. We found evidence that the observed heterozygosity-based assortative mating could be maintained by both direct and indirect benefits. Heterozygosity reflected individual quality in both sexes: egg production and quality increased with female heterozygosity while more heterozygous males showed higher feeding rates during the brood-rearing period. Further, estimated offspring heterozygosity correlated with both paternal and maternal heterozygosity, suggesting that mating with heterozygous individuals can increase offspring genetic quality. Finally, plumage crown coloration was associated with male heterozygosity, and this could explain unanimous mate preferences for highly heterozygous and more ornamented individuals. Overall, this study suggests that non-additive genetic traits may play an important role in the evolution of mating preferences and offers empirical support to the resolution of the lek paradox from the perspective of the heterozygous mate hypothesis. PMID:19474042

García-Navas, Vicente; Ortego, Joaquín; Sanz, Juan José

2009-08-22

205

Evolution of the Bipolar Mating System of the Mushroom Coprinellus disseminatus From Its Tetrapolar Ancestors Involves Loss of Mating-Type-Specific Pheromone Receptor Function  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mating incompatibility in mushroom fungi is controlled by the mating-type loci. In tetrapolar species, two unlinked mating-type loci exist (A and B), whereas in bipolar species there is only one locus. The A and B mating-type loci encode homeodomain transcription factors and pheromones and pheromone receptors, respectively. Most mushroom species have a tetrapolar mating system, but numerous transitions to bipolar mating systems have occurred. Here we determined the genes controlling mating ty...

James, Timothy Y.; Srivilai, Prayook; Ku?es, Ursula; Vilgalys, Rytas

2006-01-01

206

Localization of the Mating Type Gene in Agaricus bisporus  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The cultivated mushroom Agaricus bisporus is secondarily homothallic. Most basidia produce two basidiospores, each of which receives two of the four postmeiotic nuclei. Usually, the two packaged nuclei carry compatible mating types. Previous studies suggested that there may be only a single mating type locus in A. bisporus. In this study, we determined whether the mating type segregated as a single Mendelian determinant in a cross marked with 64 segregating molecular markers. To score mating ...

Xu, Jianping; Kerrigan, Richard W.; Horgen, Paul A.; Anderson, James B.

1993-01-01

207

On the origin of species by means of assortative mating.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Assortative mating may split a population even in the absence of natural selection. Here, we study when this happens if mating depends on one or two quantitative traits. Not surprisingly, the modes of assortative mating that can cause sympatric speciation without selection are rather strict. However, some of them may occur in nature. Slow elimination of intermediate individuals caused by the gradual tightening of assortative mating, which evolves owing to relatively weak disruptive selection,...

Kondrashov, A. S.; Shpak, M.

1998-01-01

208

Heterologous expression of mating-type genes in filamentous fungi.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Podospora anserina and Neurospora crassa, two filamentous heterothallic ascomycetes, have a single mating-type locus with two alternate forms called mat+ and mat- and A and a, respectively. Mating type controls entry into the sexual cycle, events subsequent to fertilization, and, in N. crassa, prevents the formation of mixed mating-type heterokaryons. The mating types of these two organisms display similarity in their DNA structure and in the encoded polypeptides involved in fertilization. He...

Arnaise, S.; Zickler, D.; Glass, N. L.

1993-01-01

209

Marry Your Like: Assortative Mating and Income Inequality  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Has there been an increase in positive assortative mating? Does assortative mating contribute to household income inequality? Data from the United States Census Bureau suggests there has been a rise in assortative mating. Additionally, assortative mating affects household income inequality. In particular, if matching in 2005 between husbands and wives had been random, instead of the pattern observed in the data, then the Gini coefficient would have fallen from the observed 0.43 to 0.34, so th...

Greenwood, Jeremy; Guner, Nezih; Kocharkov, Georgi; Santos, Cezar

2014-01-01

210

Life at the margin: the mating system of Mediterranean conifers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mixed mating, where a single tree progeny results from a mixture of selfing and outcrossing, is widespread in conifers and could be an evolutionary advantage at ecological margins when mating partners become scarce. This study analyzes how the mating system responds to bioclimate and density variations. We surveyed published data on the mating system of Abies, Picea and Pinus species when information on bioclimate and stand density was ...

Restoux, G.; Silva, D. E.; Sagnard, F.; Torre, F.; Klein, E.; Fady, B.

2008-01-01

211

Mating behavior and sexual selection in a polygamous beetle  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mating behavior and sexual selection in relation to morphometric traits in a polygamous beetle, Glenea cantor (F.) (Coleoptera: Cerambycidae), were investigated. Upon encounter, a male approached a female, mounted her, grasped her terminal abdomen with his hind tarsi, and attempted to mate. Successful mating lasted about 3.5 h. Although all traits measured in females and half of traits in males were significantly correlated with mating success, the primary selection on virgin females was the ...

Wen Lu, Qiao Wang

2013-01-01

212

Estimation of mating system parameters in an evolving gynodioecous population of cultivated sunflower (Helianthus annuus L.)  

Science.gov (United States)

Cultivated plants have been molded by human-induced selection, including manipulations of the mating system in the twentieth century. How these manipulations have affected realized parameters of the mating system in freely evolving cultivated populations is of interest for optimizing the management of breeding populations, predicting the fate of escaped populations and providing material for experimental evolution studies. To produce modern varieties of sunflower (Helianthus annuus L.), self-incompatibility has been broken, recurrent generations of selfing have been performed and male sterility has been introduced. Populations deriving from hybrid-F1 varieties are gynodioecious because of the segregation of a nuclear restorer of male fertility. Using both phenotypic and genotypic data at 11 microsatellite loci, we analyzed the consanguinity status of plants of the first three generations of such a population and estimated parameters related to the mating system. We showed that the resource reallocation to seed in male-sterile individuals was not significant, that inbreeding depression on seed production averaged 15–20% and that cultivated sunflower had acquired a mixed-mating system, with ?50% of selfing among the hermaphrodites. According to theoretical models, the female advantage and the inbreeding depression at the seed production stage were too low to allow the persistence of male sterility. We discuss our methods of parameter estimation and the potential of such study system in evolutionary biology. PMID:21915147

Roumet, M; Ostrowski, M-F; David, J; Tollon, C; Muller, M-H

2012-01-01

213

Progress of the Mars Array Technology Experiment (MATE) on the 2001 Lander  

Science.gov (United States)

NASA is planning missions to Mars every two years until 2010, these missions will rely on solar power. Sunlight on the surface of Mars is altered by airborne dust and fluctuates from day to day. The MATE flight experiment was designed to evaluate solar cell performance and will fly on the Mars 2001 surveyor Lander as part of the Mars In-Situ Propellant Production Precursor (MIP) package. MATE will measure several solar cell technologies and characterize the Martian environment's solar power. This will be done by measuring full IV curvers on solar cells, direct and global insolation, temperature, and spectral content. The lander is scheduled to launch in April 2001 and arrive on Mars in January of 2002. The site location has not been identified but will be near the equator, is a powered landing, and is baselined for 90 sols. The intent of this paper is to provide a brief overview of the MATE experiment and progress to date. The MATE Development Unit (DU) hardware has been built and has completed testing, work is beginning in the Qualification Unit which will start testing later this year, Flight Hardware is to be delivered next spring.

Scheiman, David A.; Baraona, Cosmo; Wilt, Dave; Jenkins, Phil; Krasowski, Michael; Greer, Lawrence; Lekki, John; Spina, Daniel; Landis, Geoff

2005-01-01

214

Diet alters species recognition in juvenile toads.  

Science.gov (United States)

Whether environmental effects during juvenile development can alter the ontogeny of adult mating behaviour remains largely unexplored. We evaluated the effect of diet on the early expression of conspecific recognition in spadefoot toads, Spea bombifrons. We found that juvenile toads display phonotaxis behaviour six weeks post-metamorphosis. However, preference for conspecifics versus heterospecifics emerged later and was diet dependent. Thus, the environment can affect the early development of species recognition in a way that might alter adult behaviour. Evaluating such effects is important for understanding variation in hybridization between species and the nature of species boundaries. PMID:24088562

Pfennig, Karin S; Moncalvo, Verónica G Rodriguez; Burmeister, Sabrina S

2013-10-23

215

HLA and mate choice in humans.  

Science.gov (United States)

Evidence from studies in rodents suggests that mate selection is influenced by major-histocompatibility-complex haplotypes, with preferences for dissimilar partners. This study was initiated to determine whether avoidance of a mate with the same HLA haplotype as one's own might be occurring in the Hutterites, a North American reproductive isolate of European ancestry, notable for their large sibships, communal lifestyle, and limited number of five-locus HLA haplotypes (HLA-A, -B, -C, -DR, and -DQ). HLA haplotypes were known for 411 Hutterite couples. The number of couples expected to match for a haplotype was calculated in two ways: first, from population genotype frequencies, with account being taken of the nonrandom mating pattern with respect to colony lineages, and, second, from computer simulations using conservative founder assumptions and the exact genealogy of the 411 couples. We observed fewer matches for HLA haplotypes between spouses than expected (first method, P = .005; second method, P = .020-.067). Among couples who did match for a haplotype, the matched haplotype was inherited from the mother in 29 cases and from the father in 50 cases (P = .018). These results are consistent with the conclusion that Hutterite mate choice is influenced by HLA haplotypes, with an avoidance of spouses with haplotypes that are the same as one's own. PMID:9326314

Ober, C; Weitkamp, L R; Cox, N; Dytch, H; Kostyu, D; Elias, S

1997-09-01

216

Unconscious Factors in Choice of a Mate  

Science.gov (United States)

If the selection of a spouse is based on the unconscious wish to correct disturbances which previously existed in the parent child relationship, the marriage is threatened from the start. This article examines motivations derived from early developmental phases which form convictions which later become the nucleus for mate choice. (Author/CJ)

Ottenheimer, Lilly

1971-01-01

217

Female mate choice in a neotropical frog.  

Science.gov (United States)

Female Physalaemus pustulosus choose their mates and are more likely to choose larger males. There is a significant negative correlation between the size of the male and the fundamental frequency of one of the components of its advertisement call. Playback experiments demonstrate that females are capable of choosing larger males by distinguishing among differences in spectral components of the advertisement call. PMID:17831371

Ryan, M J

1980-07-25

218

AA, mating of BST magnet halves  

CERN Multimedia

The AA had 2 types of bending magnets: BLG (window-frame,long and narrow) and BST (H-type, short and wide). The BST had a steel length of 2.71 m, a "good field" width of 0.564 m, and a weight of about 75 t. Here we see the mating of two BST halves.

1980-01-01

219

Mate desertion in the snail kite  

Science.gov (United States)

Mate desertion during the breeding cycle was documented at 28 of 36 (78%) snail kite, Rostrhamus sociabilis nests in Florida between 1979 and 1983. Offspring mortality occurred at only one deserted nest, however. Parents that were deserted by their mates continued to care for their young until independence (3?5 additional weeks) and provided snails at a rate similar to that of both parents combined before desertion. Males and females deserted with nearly equal frequency, except in 1982 when more females deserted. No desertion occurred during drought years, whereas desertion occurred at nearly every nest during favourable conditions. The occurrence of mate desertion was generally related to indirect measures of snail abundance: foraging range, snail delivery rates to the young and growth rates. Small broods were deserted more frequently by females than by males and tended to be deserted earlier than large ones. After desertion, deserters had the opportunity to re-mate and nest again since breeding seasons were commonly lengthy, but whether they did so was impossible to determine conclusively in most cases. The deserted bird sometimes incurred increased energetic costs and lost breeding opportunities during periods of monoparental care.

Beissinger, S.R.; Snyder, N.F.R.

1988-01-01

220

Predator-induced changes of female mating preferences: innate and experiential effects  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background In many species males face a higher predation risk than females because males display elaborate traits that evolved under sexual selection, which may attract not only females but also predators. Females are, therefore, predicted to avoid such conspicuous males under predation risk. The present study was designed to investigate predator-induced changes of female mating preferences in Atlantic mollies (Poecilia mexicana. Males of this species show a pronounced polymorphism in body size and coloration, and females prefer large, colorful males in the absence of predators. Results In dichotomous choice tests predator-naïve (lab-reared females altered their initial preference for larger males in the presence of the cichlid Cichlasoma salvini, a natural predator of P. mexicana, and preferred small males instead. This effect was considerably weaker when females were confronted visually with the non-piscivorous cichlid Vieja bifasciata or the introduced non-piscivorous Nile tilapia (Oreochromis niloticus. In contrast, predator experienced (wild-caught females did not respond to the same extent to the presence of a predator, most likely due to a learned ability to evaluate their predators' motivation to prey. Conclusions Our study highlights that (a predatory fish can have a profound influence on the expression of mating preferences of their prey (thus potentially affecting the strength of sexual selection, and females may alter their mate choice behavior strategically to reduce their own exposure to predators. (b Prey species can evolve visual predator recognition mechanisms and alter their mate choice only when a natural predator is present. (c Finally, experiential effects can play an important role, and prey species may learn to evaluate the motivational state of their predators.

Indy Jeane

2011-07-01

 
 
 
 
221

Size and competitive mating success in the yeast Saccharomyces cerevisiae  

Science.gov (United States)

In unicellular organisms like yeast, mating with the right partner is critical to future fitness because each individual can only mate once. Because cell size is important for viability, mating with a partner of the right size could be a significant advantage. To investigate this idea, we manipulated the size of unmated yeast cells and showed that their viability depended on environmental conditions; large cells do better on rich medium and small cells do better on poor medium. We also found that the fitness of offspring is determined by the size of their parents. Finally, we demonstrated that when a focal cell of one mating type was placed with a large and a small cell of the opposite mating type, it was more likely to mate with the cell that was closer to the optimum size for growth in a given environment. This pattern was not generated by differences in passive mating efficiency of large and small cells across environments but by competitive mating behavior, mate preference, or both. We conclude that the most likely mechanism underlying this interesting behavior is that yeast cells compete for mates by producing pheromone signals advertising their viability, and cells with the opportunity to choose prefer to mate with stronger signalers because such matings produce more viable offspring. PMID:24616602

2014-01-01

222

Multiple mating and sequential mate choice in guppies: females trade up.  

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The trade-up hypothesis outlines a behavioural strategy that females could use to maximize the genetic benefits to their offspring. The hypothesis proposes that females should be more willing to accept a mate when the new male encountered is a superior genetic source to previous mates. We provide a direct test of the trade-up hypothesis using guppies (Poecilia reticulata), and evaluate both behavioural and paternity data. Virgin female guppies were presented sequentially with two males of var...

Pitcher, Trevor E.; Neff, Bryan D.; Rodd, F. Helen; Rowe, Locke

2003-01-01

223

Assortative mating and differential male mating success in an ash hybrid zone population  

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Abstract Background The structure and evolution of hybrid zones depend mainly on the relative importance of dispersal and local adaptation, and on the strength of assortative mating. Here, we study the influence of dispersal, temporal isolation, variability in phenotypic traits and parasite attacks on the male mating success of two parental species and hybrids by real-time pollen flow analysis. We focus on a hybrid zone population between the two closely related ash species <...

Frascaria-Lacoste Nathalie; Fernández-Manjarrés Juan F; Austerlitz Frédéric; Klein Etienne K; Gérard Pierre R

2006-01-01

224

Sexual signals and mating patterns in Syngnathidae.  

Science.gov (United States)

Male pregnancy in the family Syngnathidae (pipefishes, seahorses and seadragons) predisposes males to limit female reproductive success; sexual selection may then operate more strongly on females and female sexual signals may evolve (sex-role reversal). A bewildering array of female signals has evolved in Syngnathids, e.g. skin folds, large body size, colouration, markings on the body and elaborate courtship. These female sexual signals do not seem quantitatively or qualitatively different from those that evolve in males in species with conventional sex roles where males provide females or offspring with direct benefits. In several syngnathid species, males also evolve ornaments, females are choosy in addition to being competitive and males compete as well as choosing partners. Thus, sex roles form a continuum, spanning from conventional to reversed within this group of fishes. Cases are presented here suggesting that stronger sexual selection on females may be most extreme in species showing classical polyandry (one male mates with several females, such as many species where males brood their eggs on the trunk), intermediate in polygynandrous species (males and females both mate with more than one partner, as in many species where males brood their eggs on the tail) and least extreme, even exhibiting conventional sex roles, in monogamous species (one male mates solely with one female, as in many seahorses and tropical pipefishes). At the same time caution is needed before unanimously establishing this pattern: first, the connection between mating patterns, strength of sexual selection, sex roles and ornament expression is far from simple and straightforward, and second, knowledge of the actual morphology, ecology and behaviour of most syngnathid species is scanty. Basically only a few Nerophis, Syngnathus and Hippocampus species have been studied in any detail. It is known, however, that this group of fishes exhibits a remarkable variation in sex roles and ornamentation, making them an ideal group for the study of mating patterns, sexual selection and sexually selected signals. PMID:21651521

Rosenqvist, G; Berglund, A

2011-06-01

225

You can't always get what you want: size assortative mating by mutual mate choice as a resolution of sexual conflict  

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Full Text Available Abstract Background Assortative mating patterns for mate quality traits like body size are often observed in nature. However, the underlying mechanisms that cause assortative mating patterns are less well known. Sexual selection is one important explanation for assortment, suggesting that i one (usually the female or both sexes could show preferences for mates of similar size or ii mutual mate choice could resolve sexual conflict over quality traits into assortment. We tested these hypotheses experimentally in the socially monogamous cichlid fish Pelvicachromis taeniatus, in which mate choice is mutual. Results In mate choice experiments, both sexes preferred large mates irrespective of own body size suggesting mating preferences are not size-assortative. Especially males were highly selective for large females, probably because female body size signals direct fitness benefits. However, when potential mates were able to interact and assess each other mutually they showed size-assortative mating patterns, i.e. the likelihood to mate was higher in pairs with low size differences between mates. Conclusion Due to variation in body size, general preferences for large mating partners result in a sexual conflict: small, lower quality individuals who prefer themselves large partners are unacceptable for larger individuals. Relative size mismatches between mates translate into a lower likelihood to mate, suggesting that the threshold to accept mates depends on own body size. These results suggest that the underlying mechanism of assortment in P. taeniatus is mutual mate choice resolving the sexual conflict over mates, rather than preference for mates of similar size.

Thünken Timo

2009-06-01

226

Social Status, Mobility and Premarital Pregnancy: A Case of Brazil  

Science.gov (United States)

The factors found to be related significantly to premarital pregnancy were educational attainment, social status of father, social status of husband, and social mobility. The data suggest the premarital pregnancy has significance for social mobility through the process of mate selection. Premarital conception may result in middle class females…

Brock, E. Wilbur; Iutaka, Sugiyama

1970-01-01

227

Parental control over mate choice to prevent marriages with out-group members: a study among mestizos, Mixtecs, and Blacks in Mexico.  

Science.gov (United States)

The present research examined how a preference for influencing the mate choice of one's offspring is associated with opposition to out-group mating among parents from three ethnic groups in the Mexican state of Oaxaca: mestizos (people of mixed descent, n = 103), indigenous Mixtecs (n = 65), and blacks (n = 35). Nearly all of the men in this study were farmworkers or fishermen. Overall, the level of preferred parental influence on mate choice was higher than in Western populations, but lower than in Asian populations. Only among the Mixtecs were fathers more in favor of parental influence on the mate choice of children than mothers were. As predicted, opposition to out-group mating was an important predictor of preferred parental influence on mate choice, more so among fathers than among mothers, especially in the mestizo group-the group with the highest status. In addition, women, and especially mestizo women, expressed more opposition to out-group mating than men did. PMID:22875548

Buunk, Abraham P; Pollet, Thomas V; Dubbs, Shelli

2012-09-01

228

Evolution of disassortative and assortative mating preferences based on imprinting.  

Science.gov (United States)

A two-locus haploid model of sexual selection is investigated to explore evolution of disassortative and assortative mating preferences based on imprinting. In this model, individuals imprint on a genetically transmitted trait during early ontogeny and choosy females later use those parental images as a criterion of mate choice. It is assumed that the presence or absence of the female preference is determined by a genetic locus. In order to incorporate such mechanisms as inbreeding depression and heterozygous advantage into our haploid framework, we assume that same-type matings are less fertile than different-type mating. The model suggests that: if all the females have a disassortative mating preference a viability-reducing trait may be maintained even without the fertility cost of same-type matings; a disassortative mating preference can be established even if it is initially rare, when there is a fertility cost of same-type matings. Further, an assortative mating preference is less likely to evolve than a disassortative mating preference. The model may be applicable to the evolution of MHC-disassortative mating preferences documented in house mice and humans. PMID:12948680

Ihara, Yasuo; Feldman, Marcus W

2003-09-01

229

Variation in male mate choice in Drosophila melanogaster.  

Science.gov (United States)

Male mate choice has been reported in the fruit fly, Drosophila melanogaster, even though males of this species were previously thought to maximise their fitness by mating with all available females. To understand the evolution of male mate choice it is important to understand variation in male mating preferences. Two studies, using different stock populations and different methods, have reported contrasting patterns of variation in male mate choice in D. melanogaster. Two possible explanations are that there are evolved differences in each stock population or that the methods used to measure choice could have biased the results. We investigated these hypotheses here by repeating the methods used in one study in which variable male mate choice was found, using the stock population from the other study in which choice was not variable. The results showed a significant resource-independent male preference for less fecund, smaller females, which contrasts with previous observations of male mate choice. This indicates that different selection pressures between populations have resulted in evolved differences in the expression of male mate choice. It also reveals phenotypic plasticity in male mate choice in response to cues encountered in each choice environment. The results highlight the importance of variation in male mate choice, and of identifying mechanisms in order to understand the evolution of mate choice under varying ecological conditions. PMID:23405271

Edward, Dominic A; Chapman, Tracey

2013-01-01

230

Mate choice based on a key ecological performance trait.  

Science.gov (United States)

Mate preference for well-adapted individuals may strengthen divergent selection and thereby facilitate adaptive divergence. We performed mate choice experiments in which we manipulated male red crossbill (Loxia curvirostra complex) feeding rates. Using association time as a proxy for preference, we found that females preferred faster foragers, which reinforces natural selection because poorly adapted males would be less likely to obtain a mate as well as less likely to survive. Although theoretical models predict direct preference for adaptation and performance, to the best of our knowledge this experiment provides the first evidence of individuals directly assessing feeding performance in mate choice. In species where assessing the ecological adaptation of potential mates is possible, females may gain fitness benefits from choosing a well-adapted mate directly or indirectly, promoting the use of information about ecological adaptation in mate choice. PMID:19320795

Snowberg, L K; Benkman, C W

2009-04-01

231

Frequency-dependent and correlational selection pressures have conflicting consequences for assortative mating in a color-polymorphic lizard, Uta stansburiana.  

Science.gov (United States)

Genetically determined polymorphisms incorporating multiple traits can persist in nature under chronic, fluctuating, and sometimes conflicting selection pressures. Balancing selection among morphs preserves equilibrium frequencies, while correlational selection maintains favorable trait combinations within each morph. Under negative frequency-dependent selection, females should mate (often disassortatively) with rare male morphotypes to produce conditionally fit offspring. Conversely, under correlational selection, females should mate assortatively to preserve coadapted gene complexes and avoid ontogenetic conflict. Using controlled breeding designs, we evaluated consequences of assortative mating patterns in color-polymorphic side-blotched lizards (Uta stansburiana), to identify conflict between these sources of selection. Females who mated disassortatively, and to conditionally high-quality males in the context of frequency-dependent selection, experienced highest fertility rates. In contrast, assortatively mated females experienced higher fetal viability rates. The trade-off between fertility and egg viability resulted in no overall fitness benefit to either assortative or disassortative mating patterns. These results suggest that ongoing conflict between correlational and frequency dependent selection in polymorphic populations may generate a trade-off between rare-morph advantage and phenotypic integration and between assortative and disassortative mating decisions. More generally, interactions among multiple sources of diversity-promoting selection can alter adaptations and dynamics predicted to arise under any of these regimes alone. PMID:25058279

Lancaster, Lesley T; McAdam, Andrew G; Hipsley, Christy A; Sinervo, Barry R

2014-08-01

232

Mating populations of Gibberella fujikuroi (Sawada S. Ito species complex isolating from maize, sorghum and wheat in Serbia  

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Full Text Available The status of fertility and distribution of mating populations in the G. fujikuroi species complex, isolating from maize, sorghum and wheat cultivated under various agroecological conditions of Serbia, have been studied. A total of 79 field isolates of Fusarium spp. in the section Liseola, which had been reciprocally crossed to standard testers (MAT-1 and MAT-2 from each of the four mating populations of the G. fujikuroi species complex, were selected for these studies. Twenty of 79 isolates belonged to the mating population A (G. moniliformis, 22 to the population D (G. intermedia, 17 to the population E (G. subglutinans and 20 to the population F (G. thapsina. A mating type MAT-1 was dominant in the populations A (14 MATA-1 :6 MATA-2, D (13 MATA-1 :9 MATA-2 and E (10 MATA-1 :7 MATA-2, while MAT-2 prevailed in the population F (6 MATA-1 : 14 MATA-2. The obtained results indicate that the possibility of sexual reproduction of Fusarium spp., belonging to the A, D, E and F mating populations, is not so frequent phenomenon in Serbia as in other regions world-wide. Consequently, these species will be asexually reproduced under field conditions, particularly species belonging to the F population. These are the first results on the characterisation of three (A, E and F out of four populations of the G. fujikuroi species complex present in Serbia. [Projekat Ministarstva nauke Republike Srbije, br. TR-31023

Kova?evi? Tamara

2013-01-01

233

Some evidence about character and mate selection.  

Science.gov (United States)

The authors conducted four studies (total N = 292) about character and mate desirability. In Study 1, undergraduates judged stimuli for attractiveness-physically and as a casual or longterm date. The target was described as faithful, having cheated but stayed with mates, or having cheated and left. Contrary to the hypothesis, men and women were equally affected by both kinds of cheaters. Study 2 replicated Study 1 with nonstudent adults. In Study 3, undergraduates rated a stimulus on the same attractiveness variables. This target had $14 million from winning a lottery or selling a dot-com company. Women, but not men, found the dot-com creator to be more physically attractive than the lottery winner. In Study 4, undergraduates rated someone who sold a cookie-making company or profited from a lucky real estate transaction. Both men and women preferred the cookie-company seller on all three measures of attractiveness. PMID:15155037

Hanko, Karlene; Master, Sarah; Sabini, John

2004-06-01

234

Sport participation influences perceptions of mate characteristics.  

Science.gov (United States)

Sport provides a context in which mate choice can be facilitated by the display of athletic prowess. Previous work has shown that, for females, team sport athletes are more desirable as mates than individual sport athletes and non-participants. In the present study, the perceptions of males and females were examined regarding potential mates based on sport participation. It was predicted that team sport athletes would be more positively perceived than individual sport athletes and non-participants by both males and females. A questionnaire, a photograph, and manipulated descriptions were used to gauge perceptual differences with respect to team sport athletes, individual sport athletes, and extra-curricular club participants for 125 females and 119 males from a Canadian university. Both team and individual sport athletes were perceived as being less lazy, more competitive, and healthier than non-participants by both males and females. Interestingly, females perceived male athletes as more promiscuous than non-athletes, which upholds predictions based on previous research indicating (a) athletes have more sexual partners than non-athletes, and (b) females find athletes more desirable as partners than non-participants. Surprisingly, only males perceived female team sport athletes as more dependable than non-participants, and both team and individual sport athletes as more ambitious. This raises questions regarding the initial hypothesis that male team athletes would be perceived positively by females because of qualities such as the ability to cooperate, likeability, and the acceptance of responsibilities necessary for group functioning. Future studies should examine similar questions with a larger sample size that encompasses multiple contexts, taking into account the role of the social profile of sport in relation to mate choice and perception. PMID:22833850

Schulte-Hostedde, Albrecht I; Eys, Mark A; Emond, Michael; Buzdon, Michael

2012-01-01

235

Multiple benefits of multiple mating in guppies  

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The rewards of promiscuity for males are undisputed. But why should a female mate promiscuously, particularly when her partners offer no resources other than sperm and increase her chances of succumbing to predation or disease? This question has been hotly debated but at present remains largely unresolved [Jennions, M. D. & Petrie, M. (2000) Biol. Rev. 75, 21–64]. One possibility is that females exploit postcopulatory mechanisms, such as sperm competition, to increase both the quality and q...

Evans, J. P.; Magurran, A. E.

2000-01-01

236

Assortative mating and fragmentation within dog breeds  

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Full Text Available Abstract Background There are around 400 internationally recognized dog breeds in the world today, with a remarkable diversity in size, shape, color and behavior. Breeds are considered to be uniform groups with similar physical characteristics, shaped by selection rooted in human preferences. This has led to a large genetic difference between breeds and a large extent of linkage disequilibrium within breeds. These characteristics are important for association mapping of candidate genes for diseases and therefore make dogs ideal models for gene mapping of human disorders. However, genetic uniformity within breeds may not always be the case. We studied patterns of genetic diversity within 164 poodles and compared it to 133 dogs from eight other breeds. Results Our analyses revealed strong population structure within poodles, with differences among some poodle groups as pronounced as those among other well-recognized breeds. Pedigree analysis going three generations back in time confirmed that subgroups within poodles result from assortative mating imposed by breed standards as well as breeder preferences. Matings have not taken place at random or within traditionally identified size classes in poodles. Instead, a novel set of five poodle groups was identified, defined by combinations of size and color, which is not officially recognized by the kennel clubs. Patterns of genetic diversity in other breeds suggest that assortative mating leading to fragmentation may be a common feature within many dog breeds. Conclusion The genetic structure observed in poodles is the result of local mating patterns, implying that breed fragmentation may be different in different countries. Such pronounced structuring within dog breeds can increase the power of association mapping studies, but also represents a serious problem if ignored. In dog breeding, individuals are selected on the basis of morphology, behaviour, working or show purposes, as well as geographic population structure. The same processes which have historically created dog breeds are still ongoing, and create further subdivision within current dog breeds.

Hailer Frank

2008-01-01

237

Periodicity and diversity in ant mating flights.  

Science.gov (United States)

1. Flight hours and seasons are alike within species, but differ among species and among genera. 2. Laboratory studies indicate internal circadian control of the phase relation to the light-dark cycle, with field evidence for modification by temperature (or other environmental variables). 3. In at least two species there is abrupt loss of obvious rhythm after mating, suggesting some special function before loss, e.g. to facilitate cross-breeding within species or reproductive isolation between species. PMID:1359949

McCluskey, E S

1992-10-01

238

Alteration processes  

International Nuclear Information System (INIS)

This session gathers 22 articles (posters) dealing with: natural systems evidence for the alteration of clay under alkaline conditions; stress corrosion cracking of carbon steel exposed to deep geological environment; the microstructure of compacted argillite submitted to an alkaline plume; the effect of the high pH alkaline solutions on the mineralogy and leachate chemistry of the Boom clay batch experiment at 60 deg. C; the effects of grouting and shotcreting on the backfill geochemistry of a KBS-3 HLNW repository; the evaluation of geochemical scenarios for iron/argillite interactions in a deep waste disposal: a density study on reaction rates and gas partial pressures; smectite interaction with metal iron; insights into long-term alteration of bentonite-cement system based on coupled mass-transport/chemical reaction analysis; the effects of alkaline alteration on water diffusivity in montmorillonite gels: NMR study; the investigation of smectite alteration and form of iron corrosion products in compacted bentonite being in contact with carbon steel for ten years; the TEM characterization of the FEBEX bentonite after two-years contact with iron corrosion products; the concrete/FEBEX bentonite interaction: preliminary results on short-term column experiments; IPHAP: background information on Philippine bentonites, hyper-alkaline waters and potential analogue sites; the Simulation of the degradation of a concrete/clay interface: influence of temperature, unsaturated conditions and porosity variations; the integrated study of 6 years in-situ steels/ argillite interactions at Tournemire by mineralogical and modelling approaches; the study of nuclear glass / canister corrosion products / clay system by means of integral modular material tests; the influence of dissolution/precipitation kinetics on the porosity clogging effect during cement/clay interactions; the alkaline perturbation into the Tournemire argillite: Structural and mineralogical studies of a 15 years in-situ propagation; the geochemical behavior of clay material under neutral and alkaline conditions at low temperature; a migration technique applied to study alteration of compacted sand-bentonite mixture in contact with concrete; the hydrothermal alteration of Callovo- Oxfordian argillite from the Paris basin by neutral and alkaline solutions at 150 deg. C and 300 deg. C and in the presence of iron metal; and some thermodynamic considerations on the behavior of Kerogen under conditions of alkaline perturbation

239

Environmentally realistic exposure to the herbicide atrazine alters some sexually selected traits in male guppies.  

Science.gov (United States)

Male mating signals, including ornaments and courtship displays, and other sexually selected traits, like male-male aggression, are largely controlled by sex hormones. Environmental pollutants, notably endocrine disrupting compounds, can interfere with the proper functioning of hormones, thereby impacting the expression of hormonally regulated traits. Atrazine, one of the most widely used herbicides, can alter sex hormone levels in exposed animals. I tested the effects of environmentally relevant atrazine exposures on mating signals and behaviors in male guppies, a sexually dimorphic freshwater fish. Prolonged atrazine exposure reduced the expression of two honest signals: the area of orange spots (ornaments) and the number of courtship displays performed. Atrazine exposure also reduced aggression towards competing males in the context of mate competition. In the wild, exposure levels vary among individuals because of differential distribution of the pollutants across habitats; hence, differently impacted males often compete for the same mates. Disrupted mating signals can reduce reproductive success as females avoid mating with perceptibly suboptimal males. Less aggressive males are at a competitive disadvantage and lose access to females. This study highlights the effects of atrazine on ecologically relevant mating signals and behaviors in exposed wildlife. Altered reproductive traits have important implications for population dynamics, evolutionary patterns, and conservation of wildlife species. PMID:22312428

Shenoy, Kausalya

2012-01-01

240

How multiple mating by females affects sexual selection.  

Science.gov (United States)

Multiple mating by females is widely thought to encourage post-mating sexual selection and enhance female fitness. We show that whether polyandrous mating has these effects depends on two conditions. Condition 1 is the pattern of sperm utilization by females; specifically, whether, among females, male mating number, m (i.e. the number of times a male mates with one or more females) covaries with male offspring number, o. Polyandrous mating enhances sexual selection only when males who are successful at multiple mating also sire most or all of each of their mates' offspring, i.e. only when Cov(?)(m,o), is positive. Condition 2 is the pattern of female reproductive life-history; specifically, whether female mating number, m, covaries with female offspring number, o. Only semelparity does not erode sexual selection, whereas iteroparity (i.e. when Cov(?)(m,o), is positive) always increases the variance in offspring numbers among females, which always decreases the intensity of sexual selection on males. To document the covariance between mating number and offspring number for each sex, it is necessary to assign progeny to all parents, as well as identify mating and non-mating individuals. To document significant fitness gains by females through iteroparity, it is necessary to determine the relative magnitudes of male as well as female contributions to the total variance in relative fitness. We show how such data can be collected, how often they are collected, and we explain the circumstances in which selection favouring multiple mating by females can be strong or weak. PMID:23339237

Shuster, Stephen M; Briggs, William R; Dennis, Patricia A

2013-03-01

 
 
 
 
241

Spatial distribution and male mating success of Anopheles gambiae swarms  

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Full Text Available Abstract Background Anopheles gambiae mates in flight at particular mating sites over specific landmarks known as swarm markers. The swarms are composed of males; females typically approach a swarm, and leave in copula. This mating aggregation looks like a lek, but appears to lack the component of female choice. To investigate the possible mechanisms promoting the evolution of swarming in this mosquito species, we looked at the variation in mating success between swarms and discussed the factors that structure it in light of the three major lekking models, known as the female preference model, the hotspot model, and the hotshot model. Results We found substantial variation in swarm size and in mating success between swarms. A strong correlation between swarm size and mating success was observed, and consistent with the hotspot model of lek formation, the per capita mating success of individual males did not increase with swarm size. For the spatial distribution of swarms, our results revealed that some display sites were more attractive to both males and females and that females were more attracted to large swarms. While the swarm markers we recognize help us in localizing swarms, they did not account for the variation in swarm size or in the swarm mating success, suggesting that mosquitoes probably are attracted to these markers, but also perceive and respond to other aspects of the swarming site. Conclusions Characterizing the mating system of a species helps understand how this species has evolved and how selective pressures operate on male and female traits. The current study looked at male mating success of An. gambiae and discussed possible factors that account for its variation. We found that swarms of An. gambiae conform to the hotspot model of lek formation. But because swarms may lack the female choice component, we propose that the An. gambiae mating system is a lek-like system that incorporates characteristics pertaining to other mating systems such as scramble mating competition.

Huestis Diana L

2011-06-01

242

No discrimination against previous mates in a sexually cannibalistic spider  

Science.gov (United States)

In several animal species, females discriminate against previous mates in subsequent mating decisions, increasing the potential for multiple paternity. In spiders, female choice may take the form of selective sexual cannibalism, which has been shown to bias paternity in favor of particular males. If cannibalistic attacks function to restrict a male's paternity, females may have little interest to remate with males having survived such an attack. We therefore studied the possibility of female discrimination against previous mates in sexually cannibalistic Argiope bruennichi, where females almost always attack their mate at the onset of copulation. We compared mating latency and copulation duration of males having experienced a previous copulation either with the same or with a different female, but found no evidence for discrimination against previous mates. However, males copulated significantly shorter when inserting into a used, compared to a previously unused, genital pore of the female.

Fromhage, Lutz; Schneider, Jutta M.

2005-09-01

243

Mating system drives negative associations between morphological features in Schistosomatidae  

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Full Text Available Abstract Background Sexual morphological features are known to be associated with the mating systems of several animal groups. However, it has been suggested that morphological features other than sexual characteristics could also be constrained by the mating system as a consequence of negative associations. Schistosomatidae are parasitic organisms that vary in mating system and can thus be used to explore links between the mating system and negative associations with morphological features. Results A comparative analysis of Schistosomatidae morphological features revealed an association between the mating system (monogamous versus polygynandrous and morphological characteristics of reproduction, nutrition, and locomotion. Conclusions The mating system drives negative associations between somatic and sexual morphological features. In monogamous species, males display a lower investment in sexual tissues and a higher commitment of resources to tissues involved in female transport, protection, and feeding assistance. In contrast, males of polygynandrous species invest to a greater extent in sexual tissues at the cost of reduced commitment to female care.

Beltran Sophie

2010-08-01

244

Exceptionally high levels of multiple mating in an army ant  

Science.gov (United States)

Most species of social insects have singly mated queens, although there are notable exceptions. Competing hypotheses have been proposed to explain the evolution of high levels of multiple mating, but this issue is far from resolved. Here we use microsatellites to investigate mating frequency in the army ant Eciton burchellii and show that queens mate with an exceptionally large number of males, eclipsing all but one other social insect species for which data are available. In addition we present evidence that suggests that mating is serial, continuing throughout the lifetime of the queen. This is the first demonstration of serial mating among social hymenoptera. We propose that high paternity within colonies is most likely to have evolved to increase genetic diversity and to counter high pathogen and parasite loads.

Denny, A. Jay; Franks, Nigel R.; Powell, Scott; Edwards, Keith J.

245

Identifying Alterity and Altering Identity  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Negative attitudes towards foreign cultures among certain categories of people in majority Islamic countries are often the result of their representations of the Other, their conception of alterity, of their identity and the relation between them, their vision of the implications of the confrontation with/or coexistence of different cultures in the same physical space or through mediated spaces. These representations have become a culture in its own right, giving birth to a categorisation of ...

Abdelghani Nait Brahim

2011-01-01

246

Both Geography and Ecology Contribute to Mating Isolation in Guppies  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Local adaptation to different environments can promote mating isolation – either as an incidental by-product of trait divergence, or as a result of selection to avoid maladaptive mating. Numerous recent empirical examples point to the common influence of divergent natural selection on speciation based largely on evidence of strong pre-mating isolation between populations from different habitat types. Accumulating evidence for natural selection's influence on speciation is therefore no longe...

Schwartz, Amy K.; Weese, Dylan J.; Bentzen, Paul; Kinnison, Michael T.; Hendry, Andrew P.

2010-01-01

247

Multiple mating and reproductive skew in Trinidadian guppies.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Male offspring production in promiscuously mating species is typically more skewed than female offspring production. It is therefore advantageous for males to seek as many mating partners as possible. However, given the documented benefits of polyandry we expect females, as well as males, to mate multiply. We tested these ideas using Trinidadian guppies, Poecilia reticulata. Fishes were collected from the wild, housed in groups of 10 males and 10 females and allowed to reproduce freely over a...

Becher, S. A.; Magurran, A. E.

2004-01-01

248

Sexual Display and Mate Choice in an Energetically Costly Environment  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Sexual displays and mate choice often take place under the same set of environmental conditions and, as a consequence, may be exposed to the same set of environmental constraints. Surprisingly, however, very few studies consider the effects of environmental costs on sexual displays and mate choice simultaneously. We conducted an experiment, manipulating water flow in large flume tanks, to examine how an energetically costly environment might affect the sexual display and mate choice behavior ...

Head, Megan L.; Wong, Bob B. M.; Brooks, Robert

2010-01-01

249

Dynamic Studies of Scaffold-dependent Mating Pathway in Yeast  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The mating pathway in \\emph{Saccharomyces cerevisiae} is one of the best understood signal transduction pathways in eukaryotes. It transmits the mating signal from plasma membrane into the nucleus through the G-protein coupled receptor and the mitogen-activated protein kinase (MAPK) cascade. According to the current understandings of the mating pathway, we construct a system of ordinary differential equations to describe the process. Our model is consistent with a wide range...

Shao, Danying; Zheng, Wen; Qiu, Wenjun; Ouyang, Qi; Tang, Chao

2006-01-01

250

Transfer of 65Zn at mating in Heliothis virescens  

International Nuclear Information System (INIS)

Male Heliothis virescens (Lepidoptera: Noctuidae) were shown to transfer 36% of a whole body 65Zn burden to the females at the time of mating. Approximately 5% of the male's and 11% of the female's total 65Zn burdens were found in eggs oviposited during a 10-day period following mating. Transfer of zinc at mating by Heliothis males may represent the conservation of an essential trace element that must be retained throughout the life cycle

251

Genetic implications of mating structure in a Caribbean isolate.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mating patterns in the population of St. Barthélémy, French West Indies, are examined to evaluate the expected genetic consequences of consanguinity avoidance and of failure to mate due to celibacy and emigration. Nearly 60% of all individuals reaching mating age on "St. Bart" never contribute to the gene pool of succeeding generations. This greatly reduces the effective population size and, therefore, increases genetic drift or random inbreeding. The consequent loss of heterozygosity is pa...

Leslie, P. W.; Morrill, W. T.; Dyke, B.

1981-01-01

252

Intermediate inheritance of Tourette syndrome, assuming assortative mating.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Segregation analysis incorporating assortative mating was used to test for major locus inheritance of Tourette syndrome in a single large pedigree containing 182 members. The analysis provided evidence of a major locus with an intermediate inheritance pattern for which the penetrance was estimated from the data as 28% in heterozygotes and 98%-99% in homozygotes. A significant assortative mating correlation was estimated from the data as 70%-79%. In contrast, when assortative mating was not in...

Hasstedt, S. J.; Leppert, M.; Filloux, F.; Wetering, B. J.; Mcmahon, W. M.

1995-01-01

253

Familiarity adds to attractiveness in matters of siskin mate choice.  

Science.gov (United States)

There is currently considerable controversy in evolutionary ecology revolving around whether social familiarity brings attraction when a female chooses a mate. The topic of familiarity is significant because by avoiding or preferring familiar individuals as mates, the potential for local adaptation may be reduced or favoured. The topic becomes even more interesting if we simultaneously analyse preferences for familiarity and sexual ornaments, because when familiarity influences female mating preferences, this could very significantly affect the strength of sexual selection on male ornamentation. Here, we have used mate-choice experiments in siskins Carduelis spinus to analyse how familiarity and patterns of ornamentation (i.e. the size of wing patches) interact to influence mating success. Our results show that females clearly prefer familiar individuals when choosing between familiar and unfamiliar males with similar-sized wing patches. Furthermore, when females were given the choice between a highly ornamented unfamiliar male and a less ornamented familiar male, half of the females still preferred the socially familiar birds as mates. Our finding suggests that male familiarity may be as important as sexual ornaments in affecting female behaviour in mate choice. Given that the potential for local adaptation may be favoured by preferring familiar individuals as mates, social familiarity as a mate-choice criterion may become a potential area of fruitful research on sympatric speciation processes. PMID:24174112

Senar, J C; Mateos-Gonzalez, F; Uribe, F; Arroyo, L

2013-12-22

254

Mating and Parental Care in Lake Tanganyika's Cichlids.  

Science.gov (United States)

Cichlid fishes of Lake Tanganyika display a variety of mating and parental care behaviors, including polygamous and monogamous mouthbrooding and substrate breeding, cooperative breeding, as well as various alternative reproductive tactics such as sneaking and piracy. Moreover, reproductive behaviors sometimes vary within species both in space and in time. Here, I survey reports on mating and parenting behaviors of Lake Tanganyika cichlid species and address the evolution of mating and parental care patterns and sexual dimorphism. Notes on measures of sexual selection intensity and the difficulties of defining mating systems and estimating selection intensities at species level conclude the essay. PMID:21822482

Sefc, Kristina M

2011-01-01

255

Sexual Experience Enhances Drosophila melanogaster Male Mating Behavior and Success  

Science.gov (United States)

Competition for mates is a wide-spread phenomenon affecting individual reproductive success. The ability of animals to adjust their behaviors in response to changing social environment is important and well documented. Drosophila melanogaster males compete with one another for matings with females and modify their reproductive behaviors based on prior social interactions. However, it remains to be determined how male social experience that culminates in mating with a female impacts subsequent male reproductive behaviors and mating success. Here we show that sexual experience enhances future mating success. Previously mated D. melanogaster males adjust their courtship behaviors and out-compete sexually inexperienced males for copulations. Interestingly, courtship experience alone is not sufficient in providing this competitive advantage, indicating that copulation plays a role in reinforcing this social learning. We also show that females use their sense of hearing to preferentially mate with experienced males when given a choice. Our results demonstrate the ability of previously mated males to learn from their positive sexual experiences and adjust their behaviors to gain a mating advantage. These experienced-based changes in behavior reveal strategies that animals likely use to increase their fecundity in natural competitive environments. PMID:24805129

Saleem, Sehresh; Ruggles, Patrick H.; Abbott, Wiley K.; Carney, Ginger E.

2014-01-01

256

Mating behavior and sexual selection in a polygamous beetle  

Directory of Open Access Journals (Sweden)

Full Text Available Mating behavior and sexual selection in relation to morphometric traits in a polygamous beetle, Glenea cantor (F. (Coleoptera: Cerambycidae, were investigated. Upon encounter, a male approached a female, mounted her, grasped her terminal abdomen with his hind tarsi, and attempted to mate. Successful mating lasted about 3.5 h. Although all traits measured in females and half of traits in males were significantly correlated with mating success, the primary selection on virgin females was the genital trait, the bursa copulatrix length, and that on males was the body length and hind tarsal length. Longer bursa copulatrix accommodated a larger ejaculate, suggesting that this female trait benefits the male that first mates with the female in terms of increasing ejaculate size to beat subsequent males in sperm competition. Under a female-biased sex ratio, more than 20% of matings failed within 20s after the male genitalia had been inserted into hers, suggesting that males assess genital features of the female before insemination and undertake cryptic male mate choice. Larger males were more capable of grasping females and achieving mating. During the premating struggle the male almost always used his hind tarsi to lift the female terminal abdomen to the position for his genitalia to insert, and as a result, males with longer hind tarsi achieved higher mating success [Current Zoology 59 (2 : 257-264, 2013].?

Wen LU, Qiao WANG, Mingyi TIAN, Jin XU, Jian LV, Aizhi QIN

2013-04-01

257

Smectite alteration  

International Nuclear Information System (INIS)

This report contains the proceedings of a second workshop in Washington DC December 8-9, 1983 on the alteration of smectites intended for use as buffer materials in the long-term containment of nuclear wastes. It includes extended summaries of all presentations and a transcript of the detailed scientific discussion. The discussions centered on three main questions: What is the prerequisite for and what is the precise mechanism by which smectite clays may be altered to illite. What are likly sources of potassium with respect to the KBS project. Is it likely that the conversion of smectite to illite will be of importance in the 10 5 to the 10 6 year time frame. The workshop was convened to review considerations and conclusions in connection to these questions and also to broaden the discussion to consider the use of smectite clays as buffer materials for similar applications in different geographical and geological settings. SKBF/KBS technical report 83-03 contains the proceedings from the first workshop on these matters that was held at the State University of New York, Buffalo May 26-27, 1982. (Author)

258

Parenting across Racial and Class Lines: Assortative Mating Patterns of New Parents Who Are Married, Cohabiting, Dating or No Longer Romantically Involved  

Science.gov (United States)

We examine the assortative mating patterns of new parents who are married, cohabiting, romantically involved and no longer romantically involved. Using data from the Fragile Families and Child Wellbeing study, we find that relationship status at the time of a birth depends mainly on father's race rather than on whether mother and father's…

Goldstein, Joshua R.; Harknett, Kristen

2006-01-01

259

Inline Electrical Connector Mate/Demate Pliers  

Science.gov (United States)

Military and aerospace industries use Mil-Spec type electrical connections on bulkhead panels that require inline access for mate and demate operations. These connectors are usually in tight proximity to other connectors, or recessed within panels. The pliers described here have been designed to work in such tight spaces, and consist of a mirrored set of parallel handles, two cross links, two return springs, and replaceable polyurethane-coated end effectors. The polyurethane eliminates metal-to-metal contact and provides a high-friction surface between the jaw and the connector. Operationally, the user would slide the pliers over the connector shell until the molded polyurethane lip makes contact with the connector shell edge. Then, by squeezing the handles, the end effector jaws grip the connector shell, allowing the connector to be easily disconnected by rotating the pliers. Mating the connector occurs by reversing the prescribed procedure, except the connector shell is placed into the jaws by hand. The molded lip within the jaw allows the user to apply additional force for difficult-to-mate connectors. Handle design has been carefully examined to maximize comfort, limit weight, incorporate tether locations, and improve ergonomics. They have been designed with an off-axis offset for wiring harness clearance, while placing the connector axis of rotation close to the user s axis of wrist rotation. This was done to eliminate fatigue during multiple connector panel servicing. To limit handle opening width, with user ergonomics in mind, the pliers were designed using a parallel jaw mechanism. A cross-link mechanism was used to complete this task, while ensuring smooth operation.

Yutko, Brian; Dininny, Michael; Moscoso, Gerand; Dokos, Adam

2010-01-01

260

Mated Fingerprint Card Pairs 2 (MFCP2)  

Science.gov (United States)

NIST Mated Fingerprint Card Pairs 2 (MFCP2) (PC database for purchase)   NIST Special Database 14 is being distributed for use in development and testing of automated fingerprint classification and matching systems on a set of images which approximate a natural horizontal distribution of the National Crime Information Center (NCIC) fingerprint classes. A newer version of the compression/decompression software on the CDROM can be found at the website http://www.nist.gov/itl/iad/ig/nigos.cfm as part of the NBIS package.

 
 
 
 
261

Are high-quality mates always attractive?: State-dependent mate preferences in birds and humans.  

Science.gov (United States)

Sexual selection theory posits that females should choose mates in a way that maximizes their reproductive success. But what exactly is the optimal choice? Most empirical research is based on the assumption that females seek a male of the highest possible quality (in terms of the genes or resources he can provide), and hence show directional preferences for indicators of male quality. This implies that attractiveness and quality should be highly correlated. However, females frequently differ in what they find attractive. New theoretical and empirical insights provide mounting evidence that a female's own quality biases her judgement of male attractiveness, such that male quality and attractiveness do not always coincide. A recent experiment in songbirds demonstrated for the first time that manipulation of female condition can lead to divergent female preferences, with low-quality females actively preferring low-quality males over high-quality males. This result is in line with theory on state-dependent mate choice and is reminiscent of assortative mating preferences in humans. Here we discuss the implications of this work for the study of mate preferences. PMID:20714411

Riebel, Katharina; Holveck, Marie-Jeanne; Verhulst, Simon; Fawcett, Tim W

2010-05-01

262

Social discrimination of cage-mates and non-cage-mates by rats.  

Science.gov (United States)

The ability to discriminate between group-mates and non-group-mates likely underpins the occurrence of affiliative and aggressive behaviour towards 'in-group' and 'out-group' individuals. Here we present two experiments aimed at testing the ability of rats (Rattus norvegicus) to discriminate between cage-mate (CM: animals residing in the subject's home cage) and non-cage-mate (NCM) conspecifics. In experiment 1, rats were trained to discriminate between different exemplars of CM and NCM using a lever pressing task employing symmetrical reinforcement. Subjects did not reach performance criterion, but they did show some evidence of discrimination between the two types of stimuli. In experiment 2, we employed a digging task to determine if rats can discriminate between odour cues from CM and NCM presented simultaneously on two sand-filled bowls. Subjects reached performance criterion on the first pair of odours, and on three more different pairs of CM and NCM odours. The results of a reversal task, using a fifth pair of odours, indicate that the rats were using a common factor to discriminate between social cues from CM and NCM conspecifics, rather than learning each pair independently. Possible candidates include a group-specific odour cue, or the development of a CM/NCM category concept. PMID:24878518

Jones, Samantha; Burman, Oliver; Mendl, Michael

2014-07-01

263

Personality and mate preferences: five factors in mate selection and marital satisfaction.  

Science.gov (United States)

Although personality characteristics figure prominently in what people want in a mate, little is known about precisely which personality characteristics are most important, whether men and women differ in their personality preferences, whether individual women or men differ in what they want, and whether individuals actually get what they want. To explore these issues, two parallel studies were conducted, one using a sample of dating couples (N = 118) and one using a sample of married couples (N = 216). The five-factor model, operationalized in adjectival form, was used to assess personality characteristics via three data sources-self--report, partner report, and independent interviewer reports. Participants evaluated on a parallel 40-item instrument their preferences for the ideal personality characteristics of their mates. Results were consistent across both studies. Women expressed a greater preference than men for a wide array of socially desirable personality traits. Individuals differed in which characteristics they desired, preferring mates who were similar to themselves and actually obtaining mates who embodied what they desired. Finally, the personality characteristics of one's partner significantly predicted marital and sexual dissatisfaction, most notably when the partner was lower on Agreeableness, Emotional Stability, and Intellect-Openness than desired. PMID:9143146

Botwin, M D; Buss, D M; Shackelford, T K

1997-03-01

264

Mating and re-mating of medflies (Diptera: Tephritidae) in Guatemala: Individual fly marking in field cages  

International Nuclear Information System (INIS)

The sterile insect technique (SIT) depends critically upon the ability of sterilized, released males to locate and mate with wild females. The overall efficiency of the method also depends upon the relative frequencies of re-mating by wild females following first matings to laboratory or wild males. Using a newly devised technique that individually marks the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), a field cage study was undertaken in a Guatemala coffee orchard to record individual fly mating behaviors between each of several laboratory strain and coffee-reared wild flies. Five laboratory strains were tested- a genetic sexing strain examined in sex ratios between 50%-100% sterile males, two standard bisexual strains, and two Fl hybrid strains. The marking technique revealed a substantial amount of information on individual fly mating and re-mating. Wild male flies significantly out-competed each of the lab strains in the first matings with both wild and lab females. Approx. 22% and 3% of wild males and females, respectively, re-mated in the field cages during two consecutive morning observation periods, while 4-8% of lab males, and 2-8% of lab females re-mated, respectively. Male flies from each lab strain averaged significantly shorter copulation times than wild males. Female flies, either lab or wild, tended to re-mate more often if they first mated to a lab male, but the differences were not statistically significant. An index was devised to providegnificant. An index was devised to provide a measure of relative male mating quality. Wild males tended to have higher individual index values than lab strain males. Average values of the latter ranged from ca. half to roughly equal that of wild males. (author)

265

Assortative mating and differential male mating success in an ash hybrid zone population  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The structure and evolution of hybrid zones depend mainly on the relative importance of dispersal and local adaptation, and on the strength of assortative mating. Here, we study the influence of dispersal, temporal isolation, variability in phenotypic traits and parasite attacks on the male mating success of two parental species and hybrids by real-time pollen flow analysis. We focus on a hybrid zone population between the two closely related ash species Fraxinus excelsior L. (common ash and F. angustifolia Vahl (narrow-leaved ash, which is composed of individuals of the two species and several hybrid types. This population is structured by flowering time: the F. excelsior individuals flower later than the F. angustifolia individuals, and the hybrid types flower in-between. Hybrids are scattered throughout the population, suggesting favorable conditions for their local adaptation. We estimate jointly the best-fitting dispersal kernel, the differences in male fecundity due to variation in phenotypic traits and level of parasite attack, and the strength of assortative mating due to differences in flowering phenology. In addition, we assess the effect of accounting for genotyping error on these estimations. Results We detected a very high pollen immigration rate and a fat-tailed dispersal kernel, counter-balanced by slight phenological assortative mating and short-distance pollen dispersal. Early intermediate flowering hybrids, which had the highest male mating success, showed optimal sex allocation and increased selfing rates. We detected asymmetry of gene flow, with early flowering trees participating more as pollen donors than late flowering trees. Conclusion This study provides striking evidence that long-distance gene flow alone is not sufficient to counter-act the effects of assortative mating and selfing. Phenological assortative mating and short-distance dispersal can create temporal and spatial structuring that appears to maintain this hybrid population. The asymmetry of gene flow, with higher fertility and increased selfing, can potentially confer a selective advantage to early flowering hybrids in the zone. In the event of climate change, hybridization may provide a means for F. angustifolia to further extend its range at the expense of F. excelsior.

Frascaria-Lacoste Nathalie

2006-11-01

266

Male Mating Strategies through Manipulation of Female-perceived Predation Risk: A Minireview and a Hypothesis  

Directory of Open Access Journals (Sweden)

Full Text Available In this minireview we focus on how males may exploit female’s sensitivity to predation risk in thecontext of mating. It has been shown in studies on guppies and jumping spiders that in response to alteredfemale behaviors, which are adaptations to the unfavorable environment and a consequence of females’ highersensitivity to predator’s presence as well as females’ higher predation risk, males can adopt condition-dependentmating tactics. It appears that in such cases males do not modify their reproductive behavior directly in responseto their own perception of predation risk, but indirectly in response to changes in female behavior induced bypredator presence. It has also been recently shown in crabs that males can exploit female behavior by creatingsafer habitat spots, which increases the male mating success. Hence all the evidence suggests that males notonly respond to female sensitivity to the natural variation in predation risk, but that males can also exploit femalebehavior by altering the environment. As a logical extension of these findings, we present a hypothesis that incertain conditions males can manipulate the environment in order to increase the predation risk and to inducefemale behaviors that enhance the male’s mating success with the increased predation risk. We propose thatsuch a manipulation to increase predation risk is expected to evolve in males of species with a strong sexualconflict and female-biased predation risk. Although empirical evidence has not been yet shown, initialobservations in a water strider species in Korea, Gerris gracilicornis, seem to support this hypothesis.

Han, Chang S

2008-02-01

267

Mating success and potential male-worker conflict in a male-dimorphic ant  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Males of many species adjust their reproductive tactics with regard to their condition and status. For example, large males may develop weapons and fight for access to females, whereas small or undernourished males do not express costly weapons or ornaments and sneak copulations. Different condition-dependent reproductive tactics may be associated with unequal average fitness, but the tactic chosen by a given male under given circumstances is thought to result in the highest possible fitness return. The ant species Cardiocondyla obscurior exhibits an environment-controlled polymorphism of docile, winged males and aggressive "ergatoid" males. Ergatoid males, which can replenish their sperm supply throughout their lives, engage in lethal fighting, and attempt to monopolize all female sexuals available in their nests, were previously assumed to gain higher lifetime reproductive success than the peaceful, winged males, which disperse to mate away from the nest and whose spermatogenesis is limited to the first days of adult life. However, precise data on male mating success have as yet not been available. Here, we compare the average mating success of the two male morphs, taking the high mortality rate of immature ergatoid males into account. Because individuals in insect societies may have opposing interests about their own development, we also investigate whether the interests of male larvae coincide with those of the workers and the rest of the society. Results When the survival probability of males is taken into account, winged males are more likely to mate multiply and in consequence have a higher estimated average mating success than ergatoid males. Therefore, male larvae are expected to prefer developing into winged instead of ergatoid adults. Conclusion Though male larvae can expect a higher average mating success when developing into winged males, most colonies produce only ergatoid males under standard conditions. This might point at a novel type of potential kin conflict within the social insect colony. Because workers in insect societies usually control male larval development, ergatoid male production under normal conditions probably reflects the optimal allocation strategy of workers to maximise their inclusive fitness.

Darrouzet Eric

2007-07-01

268

On classical and quantum error-correction in ciliate mate selection.  

Science.gov (United States)

Ciliated protozoa sensing pheromones secreted from nonself mating types engage in preconjugal "courtship" dances and contacts. Using simulated "social" trials, I recently showed the heterotrich ciliate, Spirostomum ambiguum, can learn to advertise degrees of mating fitness to "suitors" and "rivals" when serially contracting or (ciliary) reversing at variable rates. Conspicuous consumers signal higher quality reproductive status by playing "harder-to-get" via metabolically wasteful avoidance displays that hinder the exchange of preconjugal touches between "courting" couples. Conversely, prudent savers conserve energy pending situations more favorable for conjugating a partner. These ciliates reply with lower avoidance frequencies, guaranteeing nearby conspecifics of being "easier-to-get". By deciding to switch from behavioral strategies signaling conspicuous consumption to those signaling prudent savings, fitter ciliates learn to altruistically sacrifice net payoffs and persuade suitors to participate in paired reproduction. Less fit ciliates, unable to sustain long periods of high response rates, switch their behavioral strategies of prudent savings to briefly emit conspicuous consumption and thus learn to opportunistically cheat superior rivals. Mating competency depends, in part, on the efficiency of heuristics formed from recursive strategy searches and use. Heuristics represent stored patterns of action which evolve into ordered computational networks supporting entire courting repertoires. As ciliates expand signaling skills over many trials, the connectivity between strategies strengthens from Hebbian-like learning, leading to faster decisions about the appropriateness of courting messages and replies. The best experts master signaling decisions at efficiencies comparable to finding target solutions from superposed states with Grover's quantum search algorithm. I here append these findings with a critique on the feasibility of serial behavioral strategies to perfect ciliate mate selection via classical repetition and quantum bit-flip error-correction codes that safeguard transmitted social information from noise and might be exploited for signal encryption. PMID:20798831

Clark, Kevin B

2010-07-01

269

The malleability of mate selection in speed-dating events.  

Science.gov (United States)

This study examined to what extent individual mate selectivity could be explained by characteristics of the mating market. Specifically, we hypothesized that females' selectivity would be more malleable, or context-dependent, than males' mate selectivity (cf. Baumeister, 2000; Gangestad & Simpson, 2000). In a series of 22 speed-dating events in which 546 adults aged 22-42 years participated, we investigated whether the proportion of available potential mates (i.e., male-female ratio), which sex rotated during the speed-date event (i.e., approached the other sex), and mate qualities of same-sex competitors affected individuals' selectivity, as indexed by the proportion of no's given during the speed-dating events. Results from multilevel analyses demonstrated that, as hypothesized, event characteristics explained mate selectivity only for females. Specifically, women with a lower facial attractiveness and more deviant body mass index (BMI) values were overall less selective, but this trend was only present in speed-dating events characterized by higher intrasex competition--when females rotated or when other females in the event were more attractive or had healthier BMI. The findings partially support the idea of "erotic plasticity" in females, demonstrating that females' mate selectivity is more malleable and dependent on context than males' mate selectivity. PMID:23358858

Overbeek, Geertjan; Nelemans, Stefanie A; Karremans, Johan; Engels, Rutger C M E

2013-10-01

270

Human mate selection and addiction: a conceptual critique.  

Science.gov (United States)

The authors review past work on modeling human mate selection, and suggest, using illustrations from existing literature on the impact of alcoholism on relationship formation and dissolution and reproduction, that the challenges of adequately characterizing human mate selection have not yet been overcome. Some paths forwards are suggested. PMID:25138372

Heath, Andrew C; Waldron, Mary C; Martin, Nicholas G; Nelson, Elliot C; Bucholz, Kathleen K; Madden, Pamela A F

2014-09-01

271

I Want What She's Having : Evidence of Human Mate Copying.  

Science.gov (United States)

A variety of non-human females do not select male partners independently. Instead they favor males having previous associations with other females, a phenomenon known as mate copying. This paper investigates whether humans also exhibit mate copying and whether consistent positive information about a man's mate value, and a woman's age and self-perceived mate value (SPMV), influence her tendency to copy the mate choices of others. Female university students (N?=?123) rated the desirability of photographed men pictured alone or with one, two, or five women represented by silhouettes. In accordance with the visual arrays, men were described as currently in a romantic relationship; having previously been in one, two, or five relationships; or not having had a romantic relationship in the past 4 years. Women generally rated men pictured with one or two previous partners as more desirable than those with none. Men depicted with five previous partners, however, were found to be less desirable. Younger, presumably less experienced women had a greater tendency to mate copy compared with older women, but high SPMV did not predict greater levels of mate copying. The findings reaffirmed and expanded those suggesting that women do not make mate choices independently. PMID:24907050

Anderson, Ryan C; Surbey, Michele K

2014-09-01

272

Mating flights select for symmetry in honeybee drones ( Apis mellifera)  

Science.gov (United States)

Males of the honeybee ( Apis mellifera) fly to specific drone congregation areas (DCAs), which virgin queens visit in order to mate. From the thousands of drones that are reared in a single colony, only very few succeed in copulating with a queen, and therefore, a strong selection is expected to act on adult drones during their mating flights. In consequence, the gathering of drones at DCAs may serve as an indirect mate selection mechanism, assuring that queens only mate with those individuals having a better flight ability and a higher responsiveness to the queen’s visual and chemical cues. Here, we tested this idea relying on wing fluctuating asymmetry (FA) as a measure of phenotypic quality. By recapturing marked drones at a natural DCA and comparing their size and FA with a control sample of drones collected at their maternal hives, we were able to detect any selection on wing size and wing FA occurring during the mating flights. Although we found no solid evidence for selection on wing size, wing FA was found to be significantly lower in the drones collected at the DCA than in those collected at the hives. Our results demonstrate the action of selection during drone mating flights for the first time, showing that developmental stability can influence the mating ability of honeybee drones. We therefore conclude that selection during honeybee drone mating flights may confer some fitness advantages to the queens.

Jaffé, Rodolfo; Moritz, Robin F. A.

2010-03-01

273

The evolution of multiple mating in army ants.  

Science.gov (United States)

The evolution of mating systems in eusocial Hymenoptera is constrained because females mate only during a brief period early in life, whereas inseminated queens and their stored sperm may live for decades. Considerable research effort during recent years has firmly established that obligate multiple mating has evolved only a few times: in Apis honeybees, Vespula wasps, Pogonomyrmex harvester ants, Atta and Acromyrmex leaf-cutting ants, the ant Cataglyphis cursor, and in at least some army ants. Here we provide estimates of queen-mating frequency for New World Neivamyrmex and Old World Aenictus species, which, compared to other army ants, have relatively small colonies and little size polymorphism among workers. To provide the first overall comparative analysis of the evolution of army ant mating systems, we combine these new results with previous estimates for African Dorylus and New World Eciton army ants, which have very large colonies and considerable worker polymorphism. We show that queens of Neivamyrmex and Aenictus mate with the same high numbers of males (usually ca. 10-20) as do queens of army ant species with very large colony sizes. We infer that multiple queen mating is ancestral in army ants and has evolved over 100 million years ago as part of the army ant adaptive syndrome. A comparison of army ants and honeybees suggests that mating systems in these two distantly related groups may have been convergently shaped by strikingly similar selective pressures. PMID:17348950

Kronauer, Daniel J C; Johnson, Robert A; Boomsma, Jacobus J

2007-02-01

274

Mating does not influence reproductive investment, in a viviparous lizard.  

Science.gov (United States)

Mating is crucial for females that reproduce exclusively sexually and should influence their investment into reproduction. Although reproductive adjustments in response to mate quality have been tested in a wide range of species, the effect of exposure to males and mating per se has seldom been studied. Compensatory mechanisms against the absence of mating may evolve more frequently in viviparous females, which pay higher direct costs of reproduction, due to gestation, than oviparous females. To test the existence of such mechanisms in a viviparous species, we experimentally manipulated the mating opportunity of viviparous female lizard, Lacerta (Zootoca) vivipara. We assessed the effect of mating on ovulation, postpartum body condition and parturition date, as well as on changes in locomotor performances and body temperatures during the breeding cycle. Female lizards ovulated spontaneously and mating had no influence on litter size, locomotor impairment or on selected body temperature. However, offspring production induced a more pronounced locomotor impairment and physical burden than the production of undeveloped eggs. Postpartum body condition and parturition dates were not different among females. This result suggests that gestation length is not determined by an embryonic signal. In the common lizard, viviparity is not associated with facultative ovulation and a control of litter size after ovulation, in response to the absence of mating. PMID:21732546

Bleu, Josefa; Le Galliard, Jean-François; Meylan, Sandrine; Massot, Manuel; Fitze, Patrick S

2011-10-01

275

Formal Mate Selection Networks in the United States.  

Science.gov (United States)

Mate selection barriers beyond individuals' control are presented as reasons for development of formal mate selection networks. Network processes are described and classified according to the degree of third-party involvement and the degree to which anonymity of participants is protected. (Author)

Jedlicka, Davor

1980-01-01

276

Female Campus Values in Mate Selection: A Replication and Expansion.  

Science.gov (United States)

With the advent of the feminist movement it is probable that attitudes of women regarding mate selection have undergone significant changes in the 1970's. A replication of a study first conducted in 1939 which concentrated on the values and attitudes of females toward mate selection was updated using 935 single college females from 31 different…

Jones, Mary Evelyn; And Others

277

Sex Inequality, Aging, and Innovation in Preferential Mate Selection  

Science.gov (United States)

Shows that older women are likely to seek mates through the less conventional modes of mate selection and that regardless of the mode of selection, women are consistently disadvantaged. This inequality is attributed to persistence of age preferences in favor of men. (Author)

Jedlicka, Davor

1978-01-01

278

A novel case of canine disseminated aspergillosis following mating.  

Science.gov (United States)

An intact bitch with a history of mating was presented with severe lameness and a vulvar discharge. A mixed lytic, proliferative tibial lesion and open pyometra were diagnosed. Bone biopsy and uterine culture revealed disseminated aspergillosis. This is the first report of Aspergillus pyometra with dissemination following mating in the dog. PMID:22851783

Walker, Jackson T; Frazho, Jean K; Randell, Susan C

2012-02-01

279

Biased learning affects mate choice in a butterfly.  

Science.gov (United States)

Early acquisition of mate preferences or mate-preference learning is associated with signal diversity and speciation in a wide variety of animal species. However, the diversity of mechanisms of mate-preference learning across taxa remains poorly understood. Using the butterfly Bicyclus anynana we uncover a mechanism that can lead to directional sexual selection via mate-preference learning: a bias in learning enhanced ornamentation, which is independent of preexisting mating biases. Naïve females mated preferentially with wild-type males over males with enhanced wing ornamentation, but females briefly exposed to enhanced males mated significantly more often with enhanced males. In contrast, females exposed to males with reduced wing ornamentation did not learn to prefer drab males. Thus, we observe both a learned change of a preexisting mating bias, and a bias in ability to learn enhanced male ornaments over reduced ornaments. Our findings demonstrate that females are able to change their preferences in response to a single social event, and suggest a role for biased learning in the evolution of visual sexual ornamentation. PMID:22689980

Westerman, Erica L; Hodgins-Davis, Andrea; Dinwiddie, April; Monteiro, Antónia

2012-07-01

280

Lifetime Number of Mates Interacts with Female Age to Determine Reproductive Success in Female Guppies  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In many species, mating with multiple males confers benefits to females, but these benefits may be offset by the direct and indirect costs associated with elevated mating frequency. Although mating frequency (number of mating events) is often positively associated with the degree of multiple mating (actual number of males mated), most studies have experimentally separated these effects when exploring their implications for female fitness. In this paper I describe an alternative approach using...

Evans, Jonathan P.

2012-01-01

 
 
 
 
281

Conditioned place preference for mating is preserved in rats with pelvic nerve transection  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Female rats exhibit a conditioned place preference (CPP) for a context paired with mating. The present experiment tested the hypothesis that the activation of the pelvic nerve mediates the reinforcing effects of mating for female rats. Rats underwent bilateral pelvic nerve or sham transection and then received paced mating, nonpaced mating or the control treatment during a CPP procedure. Pelvic nerve transection did not affect the CPP for paced or nonpaced mating. In tests of paced mating beh...

Meerts, Sarah H.; Clark, Ann S.

2009-01-01

282

Mating behaviour and mate choice experiments in some tropical millipedes (Diplopoda: Spirostreptidae  

Directory of Open Access Journals (Sweden)

Full Text Available species of spirostreptid millipede collected from five separate localities in Zimbabwe. Mating behaviour and copulation duration were recorded. In three of the species between-population comparisons were made. The most common copulatory behaviour was highly physical with the male coiled tightly around the female. In one species (Calostreptus sp. the sexes copulated in parallel with no overt physical manoeuvring by the male. This species also had the shortest copulation duration. In single choice experiments random mating was assumed when mating frequency was independent of male body mass. This occurred in both populations of Calostreptus sp., Spinotarsus sp. 1 and one of the populations of AlIoporus uncinatus. In four cases there was a significant positive relationship between mating frequency and body mass. Only three populations mated randomly in the multiple choice experiments. In two populations mating was random in single choice and non-random in multiple choice experiments and the reverse occurred in one population of Odontopyge sp. 3. The implications of these results are discussed in relation to processes of male-male competition and female choice. *********** AFRIKAANSE OPSOMMING: Enkelvoudige en meervoudige voorkeurparing-eksperimente is uitgevoer deur die gebruik van individue van ses spesies van spirostreptide millipede wat uit vyf verskillende streke in Zimbabwe versamel is. Paringsgedrag en die tydsduur van kopulasie is aangeteken. Tussen-populasie-vergelykings is in drie van die spesies uitgevoer. Die algemeenste paringsgedrag was hoogs fisies met die mannetjie styf om die wyfie gedraai. In een van die spesies (Calostreptus sp. het die geslagte parallel aan mekaar gekopuleer met geen duidelike fisiese beweging deur die mannetjie nie. Hierdie spesie het ook die kortste kopulasieduur van al die spesies. In die enkelvoudige voorkeur-eksperimente is toevallige paring aangeneem mits die paringsfrekwensie onafhanklik was van die mannetjies se liggaamsmassa. Dit het voorgekom in beide populasies van Calostreptus sp., in Spinotarsus sp. 1 en in een van die populasies van AlIoporus uncinatus. In vier van die gevalle was daar 'n betekenisvolle positiewe verhouding tussen paringsfrekwensie en liggaamsmassa. Net drie populasies het toevallige paringsgedrag getoon in die meervoudige voorkeur-eksperimente. In twee van die populasies was paring toevallig in enkelvoudige voorkeur- en nie-toevallig in meervoudige voorkeur-eksperimente. Die teenoorgestelde het voorgekom in een populasie van Odontopyge sp. 3. Die implikasies van die resultate word bespreek in die lig van prosesse van mannetjie-mannetjie kompetisie en wyfie voorkeur.

J.M. Dangerfield

2012-01-01

283

Costs influence male mate choice in a freshwater fish.  

Science.gov (United States)

It is well known that female mate choice decisions depend on the direct costs of choosing (either because of search costs or male-imposed costs). Far less is known about how direct fitness costs affect male mate choice. We conducted an experiment to investigate male mate choice in a fish, the Pacific blue-eye (Pseudomugil signifer). Preferred females were larger, probably because larger females are also more fecund. Males, however, were consistent in their choice of female only when the costs of associating with prospective mates were equal. By contrast, males were far less consistent in their choice when made to swim against a current to remain with their initially preferred mate. Our results suggest that males may also respond adaptively to changes in the costs of choosing. PMID:12952630

Wong, Bob B M; Jennions, Michael D

2003-08-01

284

Female copying increases the variance in male mating success.  

Science.gov (United States)

Theoretical models of sexual selection assume that females choose males independently of the actions and choice of other individual females. Variance in male mating success in promiscuous species is thus interpreted as a result of phenotypic differences among males which females perceive and to which they respond. Here we show that, if some females copy the behavior of other females in choosing mates, the variance in male mating success and therefore the opportunity for sexual selection is greatly increased. Copying behavior is most likely in non-resource-based harem and lek mating systems but may occur in polygynous, territorial systems as well. It can be shown that copying behavior by females is an adaptive alternative to random choice whenever there is a cost to mate choice. We develop a statistical means of estimating the degree of female copying in natural populations where it occurs. PMID:2377613

Wade, M J; Pruett-Jones, S G

1990-08-01

285

Sexual strategies theory: an evolutionary perspective on human mating.  

Science.gov (United States)

This article proposes a contextual-evolutionary theory of human mating strategies. Both men and women are hypothesized to have evolved distinct psychological mechanisms that underlie short-term and long-term strategies. Men and women confront different adaptive problems in short-term as opposed to long-term mating contexts. Consequently, different mate preferences become activated from their strategic repertoires. Nine key hypotheses and 22 predictions from Sexual Strategies Theory are outlined and tested empirically. Adaptive problems sensitive to context include sexual accessibility, fertility assessment, commitment seeking and avoidance, immediate and enduring resource procurement, paternity certainty, assessment of mate value, and parental investment. Discussion summarizes 6 additional sources of behavioral data, outlines adaptive problems common to both sexes, and suggests additional contexts likely to cause shifts in mating strategy. PMID:8483982

Buss, D M; Schmitt, D P

1993-04-01

286

Site fidelity, mate fidelity, and breeding dispersal in American kestrels  

Science.gov (United States)

We assessed mate fidelity, nest-box fidelity, and breeding dispersal distances of American Kestrels (falco sparverius) nesting in boxes in southwestern Idaho from 1990 through 2006. Seventy-seven percent of boxes had different males and 87% had different females where nest-box occupants were identified in consecutive years. High turnover rates were partly a result of box-switching. Forty-eight percent of males and 58% of females that nested within the study area in successive years used different boxes. The probability of changing boxes was unrelated to gender, nesting success in the prior year, or years of nesting experience. Breeding dispersal distances for birds that moved to different boxes averaged 2.2 km for males (max = 22 km) and 3.2 km for females (max = 32 km). Approximately 70% of birds that nested in consecutive years on the study area had a different mate in the second year. Mate fidelity was related to box fidelity but not to prior nesting success or years of nesting experience. Mate changes occurred 32% of the time when the previous mate was known to be alive and nesting in the area. Kestrels that switched mates and boxes did not improve or decrease their subsequent nesting success. Kestrels usually switched to mates with less experience and lower lifetime productivity than their previous mates. The costs of switching boxes and mates were low, and there were no obvious benefits to fidelity. The cost of "waiting" for a previous mate that might have died could be high in species with high annual mortality.

Steenhof, K.; Peterson, B.E.

2009-01-01

287

Reduced mating success of female tortricid moths following intense pheromone auto-exposure varies with sophistication of mating system.  

Science.gov (United States)

Mating disruption is a valuable tool for the management of pest lepidopteran species in many agricultural crops. Many studies have addressed the effect of female pheromone on the ability of males to find calling females but, so far, fewer have addressed the effect of pheromone on the mating behavior of females. We hypothesized that mating of female moth species may be adversely affected following sex pheromone auto-exposure, due to abnormal behavioral activity and/or antennal sensitivity. Our results indicate that, for Grapholita molesta and Pandemis pyrusana females, copulation, but not calling, was reduced following pre-exposure to sex pheromone. In contrast, for Cydia pomonella and Choristoneura rosaceana, sex pheromone pre-exposure did not affect either calling or copulation propensity. Adaptation of female moth antennae to their own sex pheromone, following sex pheromone auto-exposure, as measured by electroantennograms, occurred in a species for which identical exposure reduced mating success (G. molesta) and in a species for which such exposure did not affect mating success (C. rosaceana). These results suggest that pre-exposure of female moths of certain species to sex pheromone may further contribute to the success of pheromone-based mating disruption. Therefore, we conclude that, in some species, mating disruption may include a secondary mechanism that affects the mating behavior of female moths, in addition to that of males. PMID:22350561

Kuhns, Emily H; Pelz-Stelinski, Kirsten; Stelinski, Lukasz L

2012-02-01

288

How universal are human mate choices? Size does not matter when Hadza foragers are choosing a mate.  

Science.gov (United States)

It has been argued that size matters on the human mate market: both stated preferences and mate choices have been found to be non-random with respect to height and weight. But how universal are these patterns? Most of the literature on human mating patterns is based on post-industrial societies. Much less is known about mating behaviour in more traditional societies. Here we investigate mate choice by analysing whether there is any evidence for non-random mating with respect to size and strength in a forager community, the Hadza of Tanzania. We test whether couples assort for height, weight, body mass index (BMI), per cent fat and grip strength. We test whether there is a male-taller norm. Finally, we test for an association between anthropometric variables and number of marriages. Our results show no evidence for assortative mating for height, weight, BMI or per cent fat; no evidence for a male-taller norm and no evidence that number of marriages is associated with our size variables. Hadza couples may assort positively for grip strength, but grip strength does not affect the number of marriages. Overall we conclude that, in contrast to post-industrial societies, mating appears to be random with respect to size in the Hadza. PMID:19570778

Sear, Rebecca; Marlowe, Frank W

2009-10-23

289

Effect of {sup 60}Co radiation processing in mate (Ilex paraguariensis); Efeito do processamento por radiacao de {sup 60}Co na erva-mate (llex paraguariensis)  

Energy Technology Data Exchange (ETDEWEB)

The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from {sup 60}Co at doses 0, 3, 5, 7 and 10 kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10 kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10 kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and qualitative profile of bioactive compounds. (author)

Furgeri, Camilo

2009-07-01

290

Effect of {sup 60}CO radiation processing in mate (Ilex paraguariensis); Efeito do processamento por radiacao de {sup 60}CO na erva-mate (Ilex paraguariensis)  

Energy Technology Data Exchange (ETDEWEB)

The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from {sup 60}Co at doses 0, 3, 5, 7 and 10kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and qualitative profile of bioactive compounds. (author)

Furgeri, Camilo

2009-07-01

291

Mating ecology explains patterns of genome elimination.  

Science.gov (United States)

Genome elimination - whereby an individual discards chromosomes inherited from one parent, and transmits only those inherited from the other parent - is found across thousands of animal species. It is more common in association with inbreeding, under male heterogamety, in males, and in the form of paternal genome elimination. However, the reasons for this broad pattern remain unclear. We develop a mathematical model to determine how degree of inbreeding, sex determination, genomic location, pattern of gene expression and parental origin of the eliminated genome interact to determine the fate of genome-elimination alleles. We find that: inbreeding promotes paternal genome elimination in the heterogametic sex; this may incur population extinction under female heterogamety, owing to eradication of males; and extinction is averted under male heterogamety, owing to countervailing sex-ratio selection. Thus, we explain the observed pattern of genome elimination. Our results highlight the interaction between mating system, sex-ratio selection and intragenomic conflict. PMID:25328085

Gardner, Andy; Ross, Laura

2014-12-01

292

Mating Instabilities Lead to Sympatric Speciation  

CERN Document Server

One of the most challenging issues of evolutionary biology concerns speciation, the emergence of new species from an initial one. The huge amount of species found in nature demands a simple and robust mechanism. Yet, no consensus has been reached concerning a reasonable disruptive selection mechanism that prevents mixing genes among the emerging species, especially when they live in sympatry. Usually it is assumed that females select males according to their displaying traits, but males perform no selection on female traits. However, recent experimental evidence accumulates towards the existence of male choice. Here we propose a robust mechanism for sympatric speciation, based on the assumption that sexual selection operates in two directions: selection of males by females and of females by males. Complex mating instabilities emerge, creating differential fitness depending on the individuals displaying traits and preferences. When a secondary sexual trait is introduced in a population, due to mutations, the a...

Almeida, C R; Almeida, Catarina R.; Abreu, Fern\\~ao Vistulo de

2002-01-01

293

Optimal mate choice patterns in pelagic copepods.  

Science.gov (United States)

The importance of sexual selection for the evolution, dynamics and adaptation of organisms is well known for many species. However, the topic is rarely studied in marine plankton, the basis of the marine food web. Copepods show behaviors that suggest the existence of sexually selected traits, and recent laboratory experiments identified some selected morphological traits. Here, we use a 'life history-based' model of sex roles to determine the optimal choosiness behavior of male and female copepods for important copepod traits. Copepod females are predicted to be choosy at population densities typically occurring during the main breeding season, whereas males are not. The main drivers of this pattern are population density and the difference in non-receptive periods between males and females. This suggests that male reproductive traits have evolved mainly due to mate competition. The model can easily be parameterized for other planktonic organisms, and be used to plan experiments about sexual selection. PMID:23180421

Heuschele, Jan; Eliassen, Sigrunn; Kiørboe, Thomas

2013-06-01

294

Stochasticity in the yeast mating pathway  

International Nuclear Information System (INIS)

We report stochastic simulations of the yeast mating signal transduction pathway. The effects of intrinsic and external noise, the influence of cell-to-cell difference in the pathway capacity, and noise propagation in the pathway have been examined. The stochastic temporal behaviour of the pathway is found to be robust to the influence of inherent fluctuations, and intrinsic noise propagates in the pathway in a uniform pattern when the yeasts are treated with pheromones of different stimulus strengths and of varied fluctuations. In agreement with recent experimental findings, extrinsic noise is found to play a more prominent role than intrinsic noise in the variability of proteins. The occurrence frequency for the reactions in the pathway are also examined and a more compact network is obtained by dropping most of the reactions of least occurrence

295

Optimal mate choice patterns in pelagic copepods  

DEFF Research Database (Denmark)

The importance of sexual selection for the evolution, dynamics and adaptation of organisms is well known for many species. However, the topic is rarely studied in marine plankton, the basis of the marine food web. Copepods show behaviors that suggest the existence of sexually selected traits, and recent laboratory experiments identified some selected morphological traits. Here, we use a ‘life history-based’ model of sex roles to determine the optimal choosiness behavior of male and female copepods for important copepod traits. Copepod females are predicted to be choosy at population densities typically occurring during the main breeding season, whereas males are not. The main drivers of this pattern are population density and the difference in non-receptive periods between males and females. This suggests that male reproductive traits have evolved mainly due to mate competition. The model can easily be parameterized for other planktonic organisms, and be used to plan experiments about sexual selection

Heuschele, Jan; KiØrboe, Thomas

2013-01-01

296

Desenvolvimento de gelatina funcional de erva-mate / Development of functional yerba-mate jelly  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O objetivo deste estudo foi desenvolver formulações para gelatina funcional com extrato de erva-mate verde e fibras solúveis como inulina (INU), frutooligossacarídeos (FOS) e a polidextrose (PD), avaliando o efeito desses ingredientes na gelatina funcional por meio da análise física da textura (firm [...] eza, consistência e coesividade), análise sensorial (sabor e preferência de compra) e composição química. As formulações INU, PD e composição INU/PD/FOS apresentaram textura desejável para uma sobremesa de gelatina, não diferindo (P>0,05) do padrão com sacarose. Pela análise sensorial, a gelatina funcional com INU obteve o maior índice hedônico para sabor e preferência de compra acima de 70%, superior ao padrão. Considerando os resultados obtidos neste estudo, a aplicação tecnológica do extrato de erva-mate verde e das fibras solúveis apresenta evidente potencial para o desenvolvimento de alimentos saudáveis e funcionais. Abstract in english The objective of this study was to develop formulations for functional jelly with extract of green yerba-mate and soluble fibers as inulin (INU), fructooligosaccharides (FOS) and polidextrose (PD), evaluating the effect of those ingredients in the functional jelly through texture physical analysis ( [...] firmness, consistence, cohesiveness), sensorial analysis (flavor and purchase preference) and chemical composition. The formulations INU, PD and composition INU/PD/FOS presented desirable texture for jelly dessert and not differing (P>0.05) of the reference standard with sucrose. For the sensorial analysis the functional jelly with INU obtained the largest index hedonic for flavor and purchase preference above 70%, higher than the reference standard. Considering the results obtained in this study, the technological application of green yerba-mate extract and of soluble fibers, presents evident potential for the development of healthy and functional foods.

Kleber Alves Santos, Berté; Dayane Rosalyn, Izidoro; Fabiana Lemos Goularte, Dutra; Rosemary, Hoffmann-Ribani.

297

Desenvolvimento de gelatina funcional de erva-mate Development of functional yerba-mate jelly  

Directory of Open Access Journals (Sweden)

Full Text Available O objetivo deste estudo foi desenvolver formulações para gelatina funcional com extrato de erva-mate verde e fibras solúveis como inulina (INU, frutooligossacarídeos (FOS e a polidextrose (PD, avaliando o efeito desses ingredientes na gelatina funcional por meio da análise física da textura (firmeza, consistência e coesividade, análise sensorial (sabor e preferência de compra e composição química. As formulações INU, PD e composição INU/PD/FOS apresentaram textura desejável para uma sobremesa de gelatina, não diferindo (P>0,05 do padrão com sacarose. Pela análise sensorial, a gelatina funcional com INU obteve o maior índice hedônico para sabor e preferência de compra acima de 70%, superior ao padrão. Considerando os resultados obtidos neste estudo, a aplicação tecnológica do extrato de erva-mate verde e das fibras solúveis apresenta evidente potencial para o desenvolvimento de alimentos saudáveis e funcionais.The objective of this study was to develop formulations for functional jelly with extract of green yerba-mate and soluble fibers as inulin (INU, fructooligosaccharides (FOS and polidextrose (PD, evaluating the effect of those ingredients in the functional jelly through texture physical analysis (firmness, consistence, cohesiveness, sensorial analysis (flavor and purchase preference and chemical composition. The formulations INU, PD and composition INU/PD/FOS presented desirable texture for jelly dessert and not differing (P>0.05 of the reference standard with sucrose. For the sensorial analysis the functional jelly with INU obtained the largest index hedonic for flavor and purchase preference above 70%, higher than the reference standard. Considering the results obtained in this study, the technological application of green yerba-mate extract and of soluble fibers, presents evident potential for the development of healthy and functional foods.

Kleber Alves Santos Berté

2011-02-01

298

Desenvolvimento de gelatina funcional de erva-mate / Development of functional yerba-mate jelly  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O objetivo deste estudo foi desenvolver formulações para gelatina funcional com extrato de erva-mate verde e fibras solúveis como inulina (INU), frutooligossacarídeos (FOS) e a polidextrose (PD), avaliando o efeito desses ingredientes na gelatina funcional por meio da análise física da textura (firm [...] eza, consistência e coesividade), análise sensorial (sabor e preferência de compra) e composição química. As formulações INU, PD e composição INU/PD/FOS apresentaram textura desejável para uma sobremesa de gelatina, não diferindo (P>0,05) do padrão com sacarose. Pela análise sensorial, a gelatina funcional com INU obteve o maior índice hedônico para sabor e preferência de compra acima de 70%, superior ao padrão. Considerando os resultados obtidos neste estudo, a aplicação tecnológica do extrato de erva-mate verde e das fibras solúveis apresenta evidente potencial para o desenvolvimento de alimentos saudáveis e funcionais. Abstract in english The objective of this study was to develop formulations for functional jelly with extract of green yerba-mate and soluble fibers as inulin (INU), fructooligosaccharides (FOS) and polidextrose (PD), evaluating the effect of those ingredients in the functional jelly through texture physical analysis ( [...] firmness, consistence, cohesiveness), sensorial analysis (flavor and purchase preference) and chemical composition. The formulations INU, PD and composition INU/PD/FOS presented desirable texture for jelly dessert and not differing (P>0.05) of the reference standard with sucrose. For the sensorial analysis the functional jelly with INU obtained the largest index hedonic for flavor and purchase preference above 70%, higher than the reference standard. Considering the results obtained in this study, the technological application of green yerba-mate extract and of soluble fibers, presents evident potential for the development of healthy and functional foods.

Kleber Alves Santos, Berté; Dayane Rosalyn, Izidoro; Fabiana Lemos Goularte, Dutra; Rosemary, Hoffmann-Ribani.

2011-02-01

299

Polygyny, mate-guarding, and posthumous fertilization as alternative male mating strategies.  

Science.gov (United States)

Alternative male mating strategies within populations are thought to be evolutionarily stable because different behaviors allow each male type to successfully gain access to females. Although alternative male strategies are widespread among animals, quantitative evidence for the success of discrete male strategies is available for only a few systems. We use nuclear microsatellites to estimate the paternity rates of three male lizard strategies previously modeled as a rock-paper-scissors game. Each strategy has strengths that allow it to outcompete one morph, and weaknesses that leave it vulnerable to the strategy of another. Blue-throated males mate-guard their females and avoid cuckoldry by yellow-throated "sneaker" males, but mate-guarding is ineffective against aggressive orange-throated neighbors. The ultradominant orange-throated males are highly polygynous and maintain large territories; they overpower blue-throated neighbors and cosire offspring with their females, but are often cuckolded by yellow-throated males. Finally, yellow-throated sneaker males sire offspring via secretive copulations and often share paternity of offspring within a female's clutch. Sneaker males sire more offspring posthumously, indicating that sperm competition may be an important component of their strategy. PMID:11106369

Zamudio, K R; Sinervo, B

2000-12-19

300

Lifetime number of mates interacts with female age to determine reproductive success in female guppies.  

Science.gov (United States)

In many species, mating with multiple males confers benefits to females, but these benefits may be offset by the direct and indirect costs associated with elevated mating frequency. Although mating frequency (number of mating events) is often positively associated with the degree of multiple mating (actual number of males mated), most studies have experimentally separated these effects when exploring their implications for female fitness. In this paper I describe an alternative approach using the guppy Poecilia reticulata, a livebearing freshwater fish in which females benefit directly and indirectly from mating with multiple males via consensual matings but incur direct and indirect costs of mating as a consequence of male sexual harassment. In the present study, females were experimentally assigned different numbers of mates throughout their lives in order to explore how elevated mating frequency and multiple mating combine to influence lifetime reproductive success (LRS) and survival (i.e. direct components of female fitness). Under this mating design, survival and LRS were not significantly affected by mating treatment, but there was a significant interaction between brood size and reproductive cycle (a correlate of female age) because females assigned to the high mating treatment produced significantly fewer offspring later in life compared to their low-mating counterparts. This negative effect of mating treatment later in life may be important in these relatively long-lived fishes, and this effect may be further exacerbated by the known cross-generational fitness costs of sexual harassment in guppies. PMID:23071816

Evans, Jonathan P

2012-01-01

 
 
 
 
301

Reversible frequency-dependent switches in male mate choice.  

Science.gov (United States)

Current sexual-selection theories predict that mating should occur preferentially with the highest-quality partner, and assume that for distinguishing among potential mates the choosy sex applies an internal representation of the characteristics of the desired mate, i.e. a template. Binary choice experiments were performed to test male mate choice between two different female colour morphs in the damselfly Ischnura elegans. Choice experiments were conducted before and after an habituation period, during which males were exposed to only one female colour morph. Given the choice between the two female morphs, males did exhibit a choice for the most recently experienced female morph. This is the first evidence for a reversible switch in mate choice in a frequency-dependent way. In contrast with previous studies on mate choice, template formation in male I. elegans seems not to be based on quality. Switching mate choice in a frequency-dependent manner, choosing the most common morph, probably allows males to minimize their search efforts and to maximize fitness. PMID:12123302

van Gossum, H; Stoks, R; De Bruyn, L

2001-01-01

302

Mate Preference of Female Blue Tits Varies with Experimental Photoperiod  

Science.gov (United States)

Organisms use environmental cues to time their life-cycles and among these cues, photoperiod is the main trigger of reproductive behaviours such as territory defence or song activity. Whether photoperiod is also important for another behaviour closely associated with reproduction, mate choice, is unknown. In many bird species, mate choice occurs at two different times during the annual cycle that strongly differ in daylength: in late winter when photoperiod is short and social mates are chosen, and again around egg-laying when photoperiod is longer and extra-pair mates are chosen. This duality makes the role that photoperiod plays on mate choice behaviours intriguing. We investigated the effect of photoperiod on mate choice using three experimental photoperiodic treatments (9 L:15 D, 14 L:10 D, 18 L:6 D), using blue tits (Cyanistes caeruleus) as a biological model. We show that female choice was stronger under long photoperiods. In addition, female blue tits spent significantly more time near males with long tarsi and long wings. This latter preference was only expressed under long photoperiods, suggesting that some indices of male quality only become significant to females when they are strongly photostimulated, and therefore that females could select their social and extra-pair mates based on different phenotypic traits. These results shed light on the roles that photoperiod may play in stimulating pair-bonding and in refining female selectivity for male traits. PMID:24671133

Reparaz, Laura B.; van Oers, Kees; Naguib, Marc; Doutrelant, Claire; Visser, Marcel E.; Caro, Samuel P.

2014-01-01

303

Anomalous diffusion and multifractality enhance mating encounters in the ocean.  

Science.gov (United States)

For millimeter-scale aquatic crustaceans such as copepods, ensuring reproductive success is a challenge as potential mates are often separated by hundreds of body lengths in a 3D environment. At the evolutionary scale, this led to the development of remote sensing abilities and behavioral strategies to locate, to track, and to capture a mate. Chemoreception plays a crucial role in increasing mate encounter rates through pheromone clouds and pheromone trails that can be followed over many body lengths. Empirical evidence of trail following behavior is, however, limited to laboratory experiments conducted in still water. An important open question concerns what happens in the turbulent waters of the surface ocean. We propose that copepods experience, and hence react to, a bulk-phase water pheromone concentration. Here we investigate the mating behavior of two key copepod species, Temora longicornis and Eurytemora affinis, to assess the role of background pheromone concentration and the relative roles played by males and females in mating encounters. We find that both males and females react to background pheromone concentration and exhibit both innate and acquired components in their mating strategies. The emerging swimming behaviors have stochastic properties that depend on pheromone concentration, sex, and species, are related to the level of reproductive experience of the individual tested, and significantly diverge from both the Lévy and Brownian models identified in predators searching for low- and high-density prey. Our results are consistent with an adaptation to increase mate encounter rates and hence to optimize reproductive fitness and success. PMID:24469823

Seuront, Laurent; Stanley, H Eugene

2014-02-11

304

Status epilepticus.  

Science.gov (United States)

Status epilepticus is a condition in which multiple epileptic seizures occur without complete recovery from the physiological effects of one seizure before another seizure occurs. There are as many types of SE as there are kinds of epileptic seizures. Generalized convulsive status epilepticus initially presents with repeated generalized convulsions without full recovery of consciousness between seizures. If untreated or undertreated, the convulsive activity becomes progressively subtle and is accompanied by a predictable series of progressive EEG changes. Non-convulsive SE refers to complex partial SE or absence SE, both of which exhibit an epileptic twilight state of altered contact with the environment. In simple partial SE there is no impairment of consciousness, and the behavioural changes reflect focal ictal discharges confined to one area of the cortex. There are between 65,000 and 150,000 cases of the SE in the US each year. Both acute and remote cerebral insults can cause SE, as can severe systemic disease that causes SE secondary to a toxic-metabolic encephalopathy. Mortality is high, but is largely a reflection of underlying aetiology when SE is treated appropriately and aggressively. Treatment is focused on terminating ongoing seizure activity as quickly as possible, both because the longer SE persists the more likely permanent neuronal damage will ensure and also because of strong evidence that the longer SE persists the more refractory to treatment it will be. Currently the most commonly accepted treatment protocol involves rapid initiation of therapy with intravenous lorazepam (0.1 mg/kg), followed, if necessary, by 20 mg/kg of phenytoin, followed, if necessary, by 20 mg/kg of phenobarbital. However, some neurologists still use intravenous diazepam (because of its more rapid antistatus effect) followed by phenytoin. New experimental data in the rat suggest that phenytoin followed by diazepam may be more effective, but this order of administration still has to tested in properly designed clinical trials. PMID:9068883

Treiman, D M

1996-12-01

305

Effects of irradiation on mating ability of Anoplophora glabripennis  

International Nuclear Information System (INIS)

Sperm of long horned beetles (LHBs), A. glabripennis, developed into mature form and became active in testes 10-14 days after emergency. A eupyrene sperm and an apyrene sperm combined together forming a normal mature sperm, and the function of apyrene sperm was helping eupyrene sperm to swim. Irradiation had no influences on sperm transfer, but had some negative influences on sperm activity. Under the cage condition, mating frequencies of different mating types were approximately accorded with the value calculated by probability. Released irradiated LHBs effectively suppressed the reproduction of normal LHBs in releasing cage. Irradiation had no evident influences on mating competitive ability of released LHBs under field-cage condition

306

Mated Fingerprint Card Pairs (Volumes 1-5)  

Science.gov (United States)

NIST Mated Fingerprint Card Pairs (Volumes 1-5) (PC database for purchase)   The NIST database of mated fingerprint card pairs (Special Database 9) consists of multiple volumes. Currently five volumes have been released. Each volume will be a 3-disk set with each CD-ROM containing 90 mated card pairs of segmented 8-bit gray scale fingerprint images (900 fingerprint image pairs per CD-ROM). A newer version of the compression/decompression software on the CDROM can be found at the website http://www.nist.gov/itl/iad/ig/nigos.cfm as part of the NBIS package.

307

Size-assortative mating and sexual size dimorphism are predictable from simple mechanics of mate-grasping behavior  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background A major challenge in evolutionary biology is to understand the typically complex interactions between diverse counter-balancing factors of Darwinian selection for size assortative mating and sexual size dimorphism. It appears that rarely a simple mechanism could provide a major explanation of these phenomena. Mechanics of behaviors can predict animal morphology, such like adaptations to locomotion in animals from various of taxa, but its potential to predict size-assortative mating and its evolutionary consequences has been less explored. Mate-grasping by males, using specialized adaptive morphologies of their forelegs, midlegs or even antennae wrapped around female body at specific locations, is a general mating strategy of many animals, but the contribution of the mechanics of this wide-spread behavior to the evolution of mating behavior and sexual size dimorphism has been largely ignored. Results Here, we explore the consequences of a simple, and previously ignored, fact that in a grasping posture the position of the male's grasping appendages relative to the female's body is often a function of body size difference between the sexes. Using an approach taken from robot mechanics we model coercive grasping of females by water strider Gerris gracilicornis males during mating initiation struggles. We determine that the male optimal size (relative to the female size, which gives the males the highest grasping force, properly predicts the experimentally measured highest mating success. Through field sampling and simulation modeling of a natural population we determine that the simple mechanical model, which ignores most of the other hypothetical counter-balancing selection pressures on body size, is sufficient to account for size-assortative mating pattern as well as species-specific sexual dimorphism in body size of G. gracilicornis. Conclusion The results indicate how a simple and previously overlooked physical mechanism common in many taxa is sufficient to account for, or importantly contribute to, size-assortative mating and its consequences for the evolution of sexual size dimorphism.

Jablonski Piotr G

2010-11-01

308

Frequency-dependent population dynamics: Effect of sex ratio and mating system on the elasticity of population growth rate.  

Science.gov (United States)

When vital rates depend on population structure (e.g., relative frequencies of males or females), an important question is how the long-term population growth rate ? responds to changes in rates. For instance, availability of mates may depend on the sex ratio of the population and hence reproductive rates could be frequency-dependent. In such cases change in any vital rate alters the structure, which in turn, affect frequency-dependent rates. We show that the elasticity of ? to a rate is the sum of (i) the effect of the linear change in the rate and (ii) the effect of nonlinear changes in frequency-dependent rates. The first component is always positive and is the classical elasticity in density-independent models obtained directly from the population projection matrix. The second component can be positive or negative and is absent in density-independent models. We explicitly express each component of the elasticity as a function of vital rates, eigenvalues and eigenvectors of the population projection matrix. We apply this result to a two-sex model, where male and female fertilities depend on adult sex ratio ? (ratio of females to males) and the mating system (e.g., polygyny) through a harmonic mating function. We show that the nonlinear component of elasticity to a survival rate is negligible only when the average number of mates (per male) is close to ?. In a strictly monogamous species, elasticity to female survival is larger than elasticity to male survival when ?<1 (less females). In a polygynous species, elasticity to female survival can be larger than that of male survival even when sex ratio is female biased. Our results show how demography and mating system together determine the response to selection on sex-specific vital rates. PMID:25174884

Haridas, C V; Eager, Eric Alan; Rebarber, Richard; Tenhumberg, Brigitte

2014-11-01

309

Sexual selection and physical attractiveness : Implications for mating dynamics.  

Science.gov (United States)

Sexual selection processes have received much attention in recent years, attention reflected in interest in human mate preferences. Among these mate preferences are preferences for physical attractiveness. Preferences in and of themselves, however, do not fully explain the nature of the relationships that individuals attain. A tacit negotiation process underlies relationship formation and maintenance. The notion that preferences for physical attractiveness evolved under parasite-driven "good genes" sexual selection leads to predictions about the nature of trade-offs that individuals make between mates' physical attractiveness and investment potential. These predictions and relevant data are explored, with a primary emphasis on women's preferences for men's qualities. In addition, further implications of trade-offs are examined, most notably (a) the impact of environmental variations on the nature of mating and (b) some effects of trade-offs on infidelity and male attempts to control women. PMID:24214365

Gangestad, S W

1993-09-01

310

Sexual overperception: power, mating motives, and biases in social judgment.  

Science.gov (United States)

Results from 4 experiments suggest that power motivates heightened perceptions and expectations of sexual interest from subordinates. Having power over a member of the opposite sex activated sexual concepts that persisted across a temporal delay, indicating the activation of a mating goal (Study 1). Having power increased participants' expectations of sexual interest from a subordinate (Study 2) but only when a mating goal was attainable (i.e., when the subordinate was romantically available; Study 3). In a face-to-face interaction between 2 participants, power heightened perceptions of sexual interest and sexualized behavior among participants with chronically active mating goals (i.e., sexually unrestricted individuals; Study 4). Tests of mediation demonstrated that sexual overperception mediated power's effect on sexually tinged behavior. Through its capacity to induce goal pursuit, power can activate mating goals that sexualize interactions between men and women. This research demonstrates one route through which power might lead to sexual harassment. PMID:21142379

Kunstman, Jonathan W; Maner, Jon K

2011-02-01

311

Do as we wish: Parental tactics of mate choice manipulation.  

Science.gov (United States)

The mate choices of children do not always meet with the approval of their parents. As a consequence, the latter employ a battery of tactics that they use to manipulate the mating behavior of the former. This paper offers the first taxonomy of parental tactics of mate choice manipulation. In particular, in Study 1, 57 semi-structured interviews revealed 72 acts that parents employ to influence their children, and 27 that they employ to influence their children's partners. In Study 2, 405 parents rated how likely they were to use these acts to influence their daughters' and sons' mate choices. Factor analysis of participants' responses revealed 12 manipulation tactics that parents use on their children, and four manipulation tactics that they use on their children's partners. PMID:23906764

Apostolou, Menelaos

2013-01-01

312

Parent-Offspring Conflict over Short-Term Mating Strategies  

Directory of Open Access Journals (Sweden)

Full Text Available Individuals engage in short-term mating strategies that enable them to obtain fitness benefits from casual relationships. These benefits, however, count for less and cost more to their parents. On this basis three hypotheses are tested. First, parents and offspring are likely to disagree over short-term mating strategies, with the former considering these as less acceptable than the latter. Second, parents are more likely to disapprove of the short-term mating strategies of their daughters than of their sons. Finally, mothers and fathers are expected to agree on how much they disagree over the short-term mating strategies of their children. Evidence from a sample of 148 Greek-Cypriot families (140 mothers, 105 fathers, 119 daughters, 77 sons provides support for the first two hypotheses and partial support for the third hypothesis. The implications of these findings for understanding family dynamics are further discussed.

Spyroulla Georgiou

2011-12-01

313

Constructing rational maps with cluster points using the mating operation  

CERN Document Server

In this article, we show that all admissible rational maps with fixed or period two cluster cycles can be constructed by the mating of polynomials. We also investigate the polynomials which make up the matings that construct these rational maps. In the one cluster case, one of the polynomials must be an $n$-rabbit and in the two cluster case, one of the maps must be either $f$, a "double rabbit", or $g$, a secondary map which lies in the wake of the double rabbit $f$. There is also a very simple combinatorial way of classifiying the maps which must partner the aforementioned polynomials to create rational maps with cluster cycles. Finally, we also investigate the multiplicities of the shared matings arising from the matings in the paper.

Sharland, Thomas

2011-01-01

314

Mate Selection and Marriage: A Psychodynamic Family-Oriented Course.  

Science.gov (United States)

A seminar for training psychologists and related professionals in the area of premarital education, via counseling testing, is described. Focus is specifically on mate selection factors operating at the unconscious level. (Author/RM)

Kemp, Hendrika Vande

1985-01-01

315

The role of chemical communication in mate choice.  

Science.gov (United States)

Chemical signals are omnipresent in sexual communication in the vast majority of living organisms. The traditional paradigm was that their main purpose in sexual behaviour was to coordinate mate and species recognition and thus pheromones were conserved in structure and function. In recent years, this view has been challenged by theoretical analyses on the evolution of pheromones and empirical reports of mate choice based on chemical signals. The ability to measure precisely the quantity and quality of chemicals emitted by single individuals has also revealed considerable individual variation in chemical composition and release rates, and there is mounting evidence that prospecting mates respond to this variation. Here, we review the evidence for pheromones as indicators of mate quality and examine the extent of their use in individual mate assessment. We begin by briefly defining the levels of mate choice--species recognition, mate recognition and mate assessment. We then explore the degree to which pheromones satisfy the key criteria necessary for their evolution and maintenance as cues in mate assessment; that is, they should exhibit variation across individuals within a sex and species; they should honestly reflect an individual's quality and thus be costly to produce and/or maintain; they should display relatively high levels of heritability. There is now substantial empirical evidence that pheromones can satisfy all these criteria and, while measurements of the actual metabolic cost of pheromone production remain to some degree lacking, trade-offs between pheromone production and various fitness-related characters such as growth rate, immunocompetence and longevity have been reported for a range of species. In the penultimate section, we outline the growing number of studies where the consequences of chemical-based mate assessment have been investigated, specifically focussing on the reported direct and genetic benefits accrued by the receiver. Finally, we highlight potential areas for future research and in particular emphasise the need for interdisciplinary research that combines exploration of chemical, physiological and behavioural processes to further our understanding of the role of chemical cues in mate assessment. PMID:17437561

Johansson, Björn G; Jones, Therésa M

2007-05-01

316

Same-sex gaze attraction influences mate-choice copying in humans.  

Science.gov (United States)

Mate-choice copying occurs when animals rely on the mating choices of others to inform their own mating decisions. The proximate mechanisms underlying mate-choice copying remain unknown. To address this question, we tracked the gaze of men and women as they viewed a series of photographs in which a potential mate was pictured beside an opposite-sex partner; the participants then indicated their willingness to engage in a long-term relationship with each potential mate. We found that both men and women expressed more interest in engaging in a relationship with a potential mate if that mate was paired with an attractive partner. Men and women's attention to partners varied with partner attractiveness and this gaze attraction influenced their subsequent mate choices. These results highlight the prevalence of non-independent mate choice in humans and implicate social attention and reward circuitry in these decisions. PMID:20161739

Yorzinski, Jessica L; Platt, Michael L

2010-01-01

317

Virgin ant queens mate with their own sons to avoid failure at colony foundation  

Science.gov (United States)

Mother-son mating (oedipal mating) is practically non-existent in social Hymenoptera, as queens typically avoid inbreeding, mate only early in life and do not mate again after having begun to lay eggs. In the ant genus Cardiocondyla mating occurs among sib in the natal nests. Sex ratios are extremely female-biased and young queens face the risk of remaining without mating partners. Here, we show that virgin queens of Cardiocondyla argyrotricha produce sons from their own unfertilized eggs and later mate with them to produce female offspring from fertilized eggs. Oedipal mating may allow C. argyrotricha queens to found new colonies when no mating partners are available and thus maintains their unusual life history combining monogyny, mating in the nest, and low male production. Our result indicates that a trait that sporadically occurs in solitary haplodiploid animals may evolve also in social Hymenoptera under appropriate ecological and social conditions.

Schmidt, Christine Vanessa; Frohschammer, Sabine; Schrempf, Alexandra; Heinze, Jürgen

2014-01-01

318

Stress responsiveness predicts individual variation in mate selectivity.  

Science.gov (United States)

Steroid hormones, including glucocorticoids, mediate a variety of behavioral and physiological processes. Circulating hormone concentrations vary substantially within populations, and although hormone titers predict reproductive success in several species, little is known about how individual variation in circulating hormone concentrations is linked with most reproductive behaviors in free-living organisms. Mate choice is an important and often costly component of reproduction that also varies substantially within populations. We examined whether energetically costly mate selection behavior in female Galápagos marine iguanas (Amblyrhynchus cristatus) was associated with individual variation in the concentrations of hormones previously shown to differ between reproductive and non-reproductive females during the breeding season (corticosterone and testosterone). Stress-induced corticosterone levels - which are suppressed in female marine iguanas during reproduction - were individually repeatable throughout the seven-week breeding period. Mate selectivity was strongly predicted by individual variation in stress-induced corticosterone: reproductive females that secreted less corticosterone in response to a standardized stressor assessed more displaying males. Neither baseline corticosterone nor testosterone predicted variation in mate selectivity. Scaled body mass was not significantly associated with mate selectivity, but females that began the breeding period in lower body condition showed a trend towards being less selective about potential mates. These results provide the first evidence that individual variation in the corticosterone stress response is associated with how selective females are in their choice of a mate, an important contributor to fitness in many species. Future research is needed to determine the functional basis of this association, and whether transient acute increases in circulating corticosterone directly mediate mate choice behaviors. PMID:23524274

Vitousek, Maren N; Romero, L Michael

2013-06-15

319

Mating with the wrong species can be right.  

Science.gov (United States)

The evolutionary importance of interspecific hybridisation has been a controversial issue for quite some time. Some view mating between different species as a maladaptive process; others stress the adaptive value of choosing heterospecific mates under ecological conditions that favour hybrids. A recent paper by Pfennig is the first study to make a priori predictions of how adaptive choice between con- and heterospecific partners should vary with ecological conditions, and then testing these predictions experimentally. PMID:18440091

Reyer, Heinz-Ulrich

2008-06-01

320

Blackmailing: the keystone in the human mating system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background The human mating system is characterized by bi-parental care and faithful monogamy is highly valued in most cultures. Marriage has evolved as a social institution and punishment for extra pair mating (EPM) or adultery is common. However, similar to other species with bi-parental care, both males and females frequently indulge in EPM in secrecy since it confers certain gender specific genetic benefits. Stability of faithful monogamy is therefore a conundrum...

Watve Milind G; Damle Anuja; Ganguly Bratati; Kale Anagha; Dahanukar Neelesh

2011-01-01

 
 
 
 
321

Radical loss of an extreme extra-pair mating system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Mating outside the pair-bond is surprisingly common in socially monogamous birds, but rates of extra-pair paternity (EPP) vary widely between species. Although differences in life-history and contemporary ecological factors may explain some interspecific variation, evolutionary forces driving extra-pair (EP) mating remain largely obscure. Also, since there is a large phylogenetic component to the frequency of EPP, evolutionary inertia may contribute substa...

Segelbacher Gernot; Hall Michelle L; Kingma Sjouke A; Peters Anne

2009-01-01

322

Positively Verifying Mating of Previously Unverifiable Flight Connectors  

Science.gov (United States)

Current practice is to uniquely key the connectors, which, when mated, could not be verified by ground tests such as those used in explosive or non-explosive initiators and pyro valves. However, this practice does not assure 100-percent correct mating. This problem could be overcome by the following approach. Errors in mating of interchangeable connectors can result in degraded or failed space mission. Mating of all flight connectors considered not verifiable via ground tests can be verified electrically by the following approach. It requires two additional wires going through the connector of interest, a few resistors, and a voltage source. The test-point voltage V(sub tp) when the connector is not mated will be the same as the input voltage, which gets attenuated by the resistor R(sub 1) when the female (F) and male (M) connectors are mated correctly and properly. The voltage at the test point will be a function of R(sub 1) and R(sub 2). Monitoring of the test point could be done on ground support equipment (GSE) only, or it can be a telemetry point. For implementation on multiple connector pairs, a different value for R(sub 1) or R(sub 2) or both can be selected for each pair of connectors that would result in a unique test point voltage for each connector pair. Each test point voltage is unique, and correct test point voltage is read only when the correct pair is mated correctly together. Thus, this design approach can be used to verify positively the correct mating of the connector pairs. This design approach can be applied to any number of connectors on the flight vehicle.

Pandipati R. K. Chetty

2011-01-01

323

Male Mating Signaling in Social Dilemma Games  

DEFF Research Database (Denmark)

According to sexual selection theory and costly signaling theory, men benefit from signaling costly mate qualities to attractive women. To date, several studies have investigated whether men use conspicuous altruism to attract women, but the findings are mixed. This study investigated whether men being observed by an attractive woman engage in competitive economic altruism in three social dilemma games—the Dictator Game, Trust Game (2nd mover), and Public Goods Game—in comparison to men being observed by a non-attractive woman. Results showed that altruistic contributions in the games were not significantly larger in the attractive observer group than in the non-attractive observer group. Exploratory analyses did reveal, however, that amongst participants with an attractive observer only, dispositional generosity had a strongly positive effect on altruism while dispositional dominance had a negative effect on altruism. Moderating effects of key individual differences suggest that the mixed findings within theempirical literature may be attributed to the existence of multiple male courtship signaling strategies. As such, the findings suggest a promising way for future studies to identify different signaling strategies, but until the findings can be replicated with specific hypothesis-driven studies they should be considered with caution.

Jensen, Niels Holm

2013-01-01

324

Gore Selects Senator Lieberman As Running Mate  

Science.gov (United States)

Yesterday, Democratic Presidential candidate Al Gore announced his selection of Connecticut Senator Joseph Lieberman as his running mate. The choice is widely seen as an attempt to separate Gore from the President's ethical controversies and to appeal to independent and Republican voters. Lieberman, the first orthodox Jew to be named to a major party's presidential ticket, was also the first Democrat to publicly criticize Clinton for his conduct in the Lewinsky affair and is known for his traditional stands on moral issues. Politically, Lieberman tends to be a centrist, even taking some typically Republican positions, such as his support of school vouchers and the privatization of Social Security. However, Republicans have already sought to paint him as a tax-loving liberal with deep ties to big business interests in health insurance and pharmaceuticals. While the choice clearly represents Gore's desire to position himself away from Clinton and in the center, some Democrats have worried that the moderate Lieberman will do little to appeal to the base of the Democratic party, namely labor, minorities, the left, and women. Unlike Bush, Gore has not yet solidified his support among these traditional Democratic constituencies. Some have also wondered aloud if Lieberman's religious affiliation will have an impact on the political race.

Charbonneau, David D.

325

Gender difference in mate preference among law students: divergence and convergence of criteria.  

Science.gov (United States)

We examined six hypotheses derived from evolutionary theory regarding sex differences in mate-selection criteria. The subjects were 160 law students who viewed color photographs of live models that were paired with different status cues such as costume variation and descriptions of income and occupation. A multivariate analysis of variance and regression analyses revealed highly significant sex differences in the following responses: reported willingness to engage in unqualified sexual relations; reported willingness to have sexual relations with stimulus persons as compared with the willingness to engage in higher investment relationships such as dating and marriage; the effects of stimulus persons' status and physical attractiveness in determining thresholds of initial acceptability; and tradeoffs, that is the ability of high physical attractiveness to compensate for low status, and of high status to compensate for low physical attractiveness. Law students also responded to nine statements concerning prospective spouses' relative income, occupational prestige, and physical attractiveness. These responses exhibited sex differences consistent with those found in the experimental manipulation. PMID:8271229

Townsend, J M; Roberts, L W

1993-09-01

326

What’s in a kiss? The effect of romantic kissing on mate desirability  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Past research suggests that various courtship rituals, such as romantic kissing, may convey useful mate quality information. Two studies were carried out to examine how purported romantic kissing abilities, as a potential cue to some form of mate information, affect appraisals of potential mating partners. In Experiment 1, 724 participants were presented with vignette descriptions of potential mating partners and were asked to rate partner desirability for various mating-related situations. T...

Wlodarski, R.; Dunbar, Rim

2014-01-01

327

Genes Controlling Mating-Type Specificity in PARAMECIUM CAUDATUM: Three Loci Revealed by Intersyngenic Crosses  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In mating interactions in Paramecium caudatum, initial mating agglutination is strictly mating-type specific, but subsequent conjugating pair formation is not mating-type specific. Using this nonspecificity of pair formation, intersyngenic (intersibling species) pairs were induced by mixing four mating types of two different syngens. To distinguish intersyngenic pairs from intrasyngenic ones, the behavioral marker CNR (Takahashi 1979) was mainly used. Clones of intersyngenic hybrids showed hi...

Tsukii, Yuuji; Hiwatashi, Koichi

1983-01-01

328

Specific and common epitopes in mating pheromones of Euplotes raikovi revealed by monoclonal antibodies  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Polypeptide mating pheromones Er-1 and Er-2, purified from the supernatant of Euplotes raikovi cultures of mating type I and mating type II, respectively, were used to immunize mice and obtain monoclonal antibodies. Five hybridoma clones producing antibodies specific to the mating pheromones were selected. They were analyzed for immunospecificity by immunoperoxidase assay, immunoblotting, and for their efficacy in inhibition of mating pheromone activity. Monoclonal antibodies from two hybrido...

Fiori, Pier Luigi; Miceli, Cristina; Raffioni, Simona; Vallesi, Adriana

1990-01-01

329

Determinants of Natural Mating Success in the Cannibalistic Orb-Web Spider Argiope bruennichi  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Monogynous mating systems (low male mating rates) occur in various taxa and have evolved several times independently in spiders. Monogyny is associated with remarkable male mating strategies and predicted to evolve under a male-biased sex ratio. While male reproductive strategies are well documented and male mating rates are easy to quantify, especially in sexually cannibalistic species, female reproductive strategies, the optimal female mating rate, and the factors that affect the evolution ...

Zimmer, Stefanie M.; Welke, Klaas W.; Schneider, Jutta M.

2012-01-01

330

Genetic evidence confirms polygamous mating system in a crustacean parasite with multiple hosts.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mating systems are diverse in animals, notably in crustaceans, but can be inferred from a limited set of parameters. Baeza and Thiel (2007) proposed a model predicting mating systems of symbiotic crustaceans with three host characteristics and the risk of predation. These authors proposed five mating systems, ranging from monogamy to polygynandry (where multiple mating occurs for both genders). Using microsatellite loci, we tested the putatively mating system of the ectoparasite crab Dissodac...

Jossart, Quentin; Wattier, Re?mi A.; Kastally, Cheldy; Aron, Serge; David, B.; Ridder, Chantal; Rigaud, Thierry

2014-01-01

331

Effect of the Sterilizing dose of Gamma Irradiation on Mating Performance and Female re-mating of Mediterranean Fruit Fly, Ceratitis capitata (Wied)  

International Nuclear Information System (INIS)

The population suppression success of Mediterranean fruit fly, Ceratitis capitata (Wied.) using sterile insect technique (SIT) depends mainly upon the ability of sterilized males to locate and mate with wild females. The efficiency of the SIT also depends upon the relative frequencies of re-mating by wild females following first mating with sterilized or wild males. A semi field cage test was conducted to study the effect of three different sterilizing doses of gamma irradiation on the male mating performance. No significant differences were found in the ability of mating, the mating duration and mating site between the un-irradiated males and irradiated ones with the doses (80, 90 and 100 Gy) The irradiated males with the dose 80 Gy revealed mating ability higher than the irradiated males with the other doses (90 and 100 Gy) although un-irradiated males had a general higher ability than irradiated ones.

332

Non-Random Mating, Parent-of-Origin, and Maternal-Fetal Incompatibility Effects in Schizophrenia  

Science.gov (United States)

Although the association of common genetic variation in the extended MHC region with schizophrenia is the most significant yet discovered, the MHC region is one of the more complex regions of the human genome, with unusually high gene density and long-range linkage disequilibrium. The statistical test on which the MHC association is based is a relatively simple, additive model which uses logistic regression of SNP genotypes to predict case-control status. However, it is plausible that more complex models underlie this association. Using a well-characterized sample of trios, we evaluated more complex models by looking for evidence for: (a) non-random mating for HLA alleles, schizophrenia risk profiles, and ancestry; (b) parent-of-origin effects for HLA alleles; and (c) maternal-fetal genotype incompatibility in the HLA. We found no evidence for non-random mating in the parents of individuals with schizophrenia in terms of MHC genotypes or schizophrenia risk profile scores. However, there was evidence of non-random mating that appeared mostly to be driven by ancestry. We did not detect over-transmission of HLA alleles to affected offspring via the general TDT test (without regard to parent of origin) or preferential transmission via paternal or maternal inheritance. We evaluated the hypothesis that maternal-fetal HLA incompatibility may increase risk for schizophrenia using eight classical HLA loci. The most significant alleles were in HLA-B, HLA-C, HLA-DQB1, and HLA-DRB1 but none was significant after accounting for multiple comparisons. We did not find evidence to support more complex models of gene action, but statistical power may have been limiting. PMID:23177929

Kim, Yunjung; Ripke, Stephan; Kirov, George; Sklar, Pamela; Purcell, Shaun; Owen, Michael; O'Donovan, Michael C.; Sullivan, Patrick F.

2014-01-01

333

Interspecific actions of alpha mating pheromones on the a mating-type cells of three Saccharomyces yeasts.  

Science.gov (United States)

The alpha mating pheromones synthesized in three Saccharomyces yeasts (S. cerevisiae, S. kluyveri, and S. exiguus) displayed interspecific actions on the a cells of all three species despite the fact that the amino acid sequences of all three alpha pheromones are different. Mating between species, however, did not occur. The interspecific alpha pheromone--a cell reaction was not necessarily more effective than the interspecific one. PMID:3282694

Hisatomi, T; Yanagishima, N; Sakurai, A; Kobayashi, H

1988-01-01

334

Reproductive consequences of mate quantity versus mate diversity in a wind-pollinated plant  

Science.gov (United States)

Since most pollen travels limited distances in wind-pollinated plants, both the local quantity and diversity of mates may limit female reproductive success. Yet little evidence exists on their relative contribution, despite the importance of viable seed production to population dynamics. To study how variation in female reproductive success is affected by the quantity versus the diversity of surrounding mates contributing pollen, we integrated pollination experiments, data on natural seed set and seed viability, and AFLP genetic marker data in the wind-pollinated dioecious clonal forest herb Mercurialis perennis. Pollination experiments indicated weak quantitative pollen limitation effects on seed set. Among-population crosses showed reduced seed viability, suggesting outbreeding depression due to genetic divergence. Pollination with pollen from a single source did not negatively affect reproductive success. These findings were consistent with results of the survey of natural female reproductive success. Seed set decreased with the distance to males in a female plants' local neighborhood, suggesting a shortage of pollen in isolated female plants, and increased with the degree of local genetic diversity. Spatial isolation to other populations and population size did not affect seed set. None of these variables were related to seed viability. We conclude that pollen movement in M. perennis is likely very limited. Both male proximity and the local degree of genetic diversity influenced female reproductive success.

Vandepitte, K.; Roldán-Ruiz, I.; Honnay, O.

2009-07-01

335

[Calling and mating behaviors of bamboo shoot borer Kumasia kumaso].  

Science.gov (United States)

The calling and mating behaviors of Kumasia kumaso were studied in laboratory at (25 1) degrees C and (60 +/- 10) % RH under a cycle 14 L:10 D photo period, and the EAG response of male K. kumaso to female K. kumaso sex gland extracts was also tested. The calling and mating behaviors of K. kumaso could only be observed in scotophase. The females began calling at the first scotophase following emergence, and the peak of calling occurred during the second scotophase and decreased thereafter. The calling of the females commenced 0-4 h after dark, reached the maximum between the 5th and the 7th hour of the scotophase, and terminated during the last 1-2.5 h of the scotophase. Moth age had significant effects on the calling patterns. With increasing moth age, the onset time of calling advanced gradually, and the mean number of calling bouts as well as the calling length per bout had a gradual increase from calling day 1 to day 4 but decreased on day 5. The peak time and terminated time of calling advanced with increasing moth age. The mating of K. kumaso adults initiated during the first scotophase and terminated till the 5th scotophase following emergence, and the peak of mating was observed during the second scotophase. The peak of mating was observed 5.5-7.0 h after dark, and advanced with increasing moth age. Moth age affected the mean onset time of mating and the copulation duration significantly. With increasing moth age, the mean onset time of mating advanced, and the copulation duration decreased. Sex ratio had significant effects on the mating behavior as well. Treatment 2 female:1 male showed a significantly higher mating percentage, but an earlier onset time of mating and shorter copulation duration, as compared with treatment 1 female:1 male. The results of EAG test indicated that the male adults showed a significant EAG response to the sex gland extracts of 2-day-old virgin females. PMID:23479886

Shu, Jin-Ping; Teng, Ying; Zhang, Ai-Liang; Zhang, Ya-Bo; Deng, Shun; Wang, Hao-Jie

2012-12-01

336

Male rock sparrows adjust their breeding strategy according to female ornamentation: parental or mating investment?  

DEFF Research Database (Denmark)

We investigated the relations between female quality and ornamentation and between male breeding investment and female ornamentation in the rock sparrow, Petronia petronia, a passerine in which both sexes have a yellow breast patch. Breast patch size in females was positively correlated with body mass and breeding status; double-brooding and primary females of polygynous males had a larger patch, and patch size could therefore be an indicator of female phenotypic quality. We conducted a field experiment to test whether males allocate their parental effort in relation to female quality, as predicted by the differential allocation hypothesis. We increased and reduced the ornament sizes of paired females and compared the behaviour of their males before and after manipulation. Frequency of brood feeding by the male was not affected by female ornament manipulation; there was a nonsignificant trend for females with enlarged ornaments, contrary to predictions, to increase their feeding rate. Reducing female ornaments resulted in a decrease in male nest attendance, a measure of passive brood defence, whereas enlarging the ornament had no effect. Males concurrently reduced their territorial (song output) and sexual activity (courtship and copulation). The reduction in sexual activity suggests that males may have changed their nest attendance in response to their mate's renesting probability. Whatever the interpretation, these results provide some of the first evidence that not only female, but also male, birds change breeding strategy according to their mate's phenotype in the wild.

Pilastro, Andrea; Griggio, Matteo

2003-01-01

337

The use of twins in the analysis of assortative mating.  

Science.gov (United States)

The simulations illustrated show that a plausible model for mate selection can generate data on the similarity of twins and their spouses which are remarkably consistent with a transitive model for the effects of mate selection. This is, biological considerations impose constraints upon the relative values of correlations which are not foreseen, for example, by the some advocates of conventional path models although they might be predicted by common sense. In particular, the correlation between the spouses of twins is expected to be non-zero under a model of phenotypic assortment and turns out to be approximately equal to the product of the twin correlation and the square of the marital correlation. The relative magnitudes of the correlations derived from an empirical study of such relationships should enable models of phenotypic assortment to be tested more rigorously. Including both identical and non-identical twins in the sample studied should permit the inherited and cultural components of the mating system to be identified with more conviction. In the event of one sex playing a more significant role in mate selection for particular traits, such studies should reveal diagnostic patterns of familial correlations as long as male and female twins and their spouses are analysed separately. If the analysis is restricted to phenotypic correlations of the parents, the qualitative findings do not appear to be greatly affected by selection due to assortative mating although a reduction in variance is to be expected if a large proportion of individuals is unable to mate. In such cases twins will also be significantly concordant for mating. The consequences of such varied regimes of assortation for the population structure and the relationship between traits in subsequent generations remain the object of future inquiry. PMID:575719

Eaves, L

1979-12-01

338

Radical loss of an extreme extra-pair mating system  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Mating outside the pair-bond is surprisingly common in socially monogamous birds, but rates of extra-pair paternity (EPP vary widely between species. Although differences in life-history and contemporary ecological factors may explain some interspecific variation, evolutionary forces driving extra-pair (EP mating remain largely obscure. Also, since there is a large phylogenetic component to the frequency of EPP, evolutionary inertia may contribute substantially to observed EP mating patterns. However, the relative importance of plasticity and phylogenetic constraints on the incidence of EP mating remains largely unknown. Results We here demonstrate very low levels of EPP (4.4% of offspring in the purple-crowned fairy-wren Malurus coronatus, a member of the genus with the highest known levels of EPP in birds. In addition, we show absence of the suite of distinctive behavioral and morphological adaptations associated with EP mating that characterize other fairy-wrens. Phylogenetic parsimony implies that these characteristics were lost in one speciation event. Nonetheless, many life-history and breeding parameters that are hypothesized to drive interspecific variation in EPP are not different in the purple-crowned fairy-wren compared to its promiscuous congeners. Conclusion Such radical loss of an extreme EP mating system with all associated adaptations from a lineage of biologically very similar species indicates that evolutionary inertia does not necessarily constrain interspecific variation in EPP. Moreover, if apparently minor interspecific differences regularly cause large differences in EPP, this may be one reason why the evolution of EP mating is still poorly understood.

Segelbacher Gernot

2009-05-01

339

Human mate selection under competitive pressure  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Stable, cross-cultural, gender-based preferences in relationship choices have been identified by evolutionary psychologists (Buss 1987, Symons and Ellis 1989). This study furthered such research by collecting data from 20 participants (10 male, 10 female) using a mixed design. Participants completed three questionnaires on sexual orientation and relationship status, their attitudes towards aspects of relationships, and a trait-rating scale (a replication of Buss 1989). Participants then answe...

Hope, David

2006-01-01

340

Long-term alteration of cementitious materials  

International Nuclear Information System (INIS)

Long-term alteration of cementitious materials in the geological condition has been discussed for the safety assessment of radioactive waste disposal. This paper describes the status of understanding long-term chemical alteration of cement, by reviewing some of our investigations on this issue in which we developed a thermodynamic incongruent C-S-H dissolution/precipitation model and a reactive transport calculation code. Alteration of C-S-H gel in a saline groundwater and the change of chemical barrier performance of cementitious materials due to the alteration are also discussed. Some key issues to be discussed further are given and suggested for the future studies on the long-term alteration of cementitious materials in the repository environment. (author)

 
 
 
 
341

Code Status  

Science.gov (United States)

... Home Clinical Critical Care Information for Patients | | More Code Status Information for Patients Introduction General Information Common ... Approaches in Critical Care Commonly Asked Questions Credits "Code status" are the words used by hospital staff ...

342

What do women's advertised mate preferences reveal? An analysis of video dating profiles.  

Science.gov (United States)

This study examined women's video dating profiles to determine what their advertised mate preferences revealed about their mate value and relationship interests. Women created a one-minute long video dating profile for a hypothetical dating website. The videos were content analyzed into four categories of stated mate preferences: 1) "good genes" indicators 2) good resource investment potential indicators 3) good parenting indicators and 4) good partner indicators. Long-term mating interest was positively correlated with describing good partner indicators and self-perceived mate value was positively correlated with describing good genes indicators. Short-term mating interest was negatively correlated with describing any mate preferences while attractiveness was positively correlated with doing so. Results suggest that women's advertised mate preferences provide clues to their underlying relationship interests and mate value. PMID:23718946

Goetz, Cari D

2013-01-01

343

Factors affecting female re-mating frequency in the Mediterranean fruit fly (Diptera: Tephritidae)  

International Nuclear Information System (INIS)

Mating and re-mating of two laboratory strains (Petapa and Guate), one wild population (Antigua) of Ceratitis capitata (Wiedemann) and one of the hybrids between them were studied under laboratory conditions. No evidence of sexual isolation at first mating was found among them. Re-mating frequency was higher under crowded conditions for the two laboratory strains. The probability of Pe tap a females re-mating depended more on the origin of the male and was negatively associated with the duration of the first mating, but these variables had no effect on re-mating tendency of Guate females. Matings by Petapa males were significantly less prolonged than those of Guate or hybrid males. With respect to re-mating, Petapa non-virgin females preferred Petapa to Guate males. (author)

344

Chemical characterization of candy made of Erva-Mate (Ilex paraguariensis A. St. Hil.) residue.  

Science.gov (United States)

The aim of this work was to evaluate the chemical properties of the residues from erva-mate processing and also to determine the candy-making performance with addition of residues from erva-mate on consumers' acceptance and purchase intent of this new product. The candies containing different amounts of mate powder were evaluated through overall acceptability test and purchase intent. Mate powder showed high contents of dietary fiber, total ash, and total polyphenols. The total dietary fiber content of the mate candies ranged from 5.7 to 6.29% on a dry matter basis. Supplementation with mate powder caused significant increases in polyphenol and mineral contents of mate candies. The incorporation of mate powder increased the hardness of the candies and produced desirable results in their nutritional characteristics. The sensory tests indicated that mate candies were acceptable and approved in relation to purchase intent. PMID:18500809

Vieira, Manoela A; Rovaris, Angela A; Maraschin, Marcelo; De Simas, Karina N; Pagliosa, Cristiane M; Podestá, Rossana; Amboni, Renata D M C; Barreto, Pedro L M; Amante, Edna R

2008-06-25

345

Does mating interfere in the biological characteristics of a population of Trichogramma pretiosum?  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Trichogramma spp. são parasitoides utilizados na regulação de populações de insetos que podem causar danos econômicos. Para que esses tenham bom desempenho é essencial o conhecimento de algumas de suas características biológicas. O objetivo deste trabalho foi avaliar se o acasalamento interfere nas [...] características biológicas de uma população de Trichogramma pretiosum coletada em campo. Em todos os experimentos, grupos de fêmeas acasaladas e não acasaladas foram utilizados. Além disso, foi verificada a interferência do acasalamento nas características biológicas dos descendentes. Foi constatado que o acasalamento é capaz de alterar o parasitismo e a longevidade das fêmeas genitoras, além de alterar a longevidade entre os descendentes, porém, uma vez parasitados, os ovos se desenvolvem normalmente, apresentando viabilidade e número de descendentes similares aos das fêmeas não acasaladas. Verificamos ainda, que a população de T. pretiosum coletada em campo apresentou indivíduos com características reprodutivas telítocas e arrenótocas. Esse fato ressalta a importância de investigações cuidadosas sobre o modo de reprodução das populações coletadas em campo, evitando assim problemas de eficiência no manejo de populações de insetos. Abstract in english Trichogramma spp. are parasitoids used in the regulation of insect populations that can cause economic damage. In order to ensure good performance, understanding some of their biological characteristics is essential. The objective of this study is to evaluate whether mating interferes with the biol [...] ogical characteristics of a population of Trichogramma pretiosum collected in the field. In all experiments, groups of mated and unmated females were used. We also verified any interference from mating on the biological characteristics of the offspring. We found that mating can alter the parasitism and longevity of genitor females, in addition to changing longevity among the descendants, but once parasitized, the eggs develop normally, showing similar emergence percentage and number of offspring as those from unmated females. In addition, we verified that the population of T. pretiosum collected in the field presented individuals with reproductive thelytokous and arrhenotokous characteristics. This fact highlights the importance of careful investigation on the reproduction mode of populations collected in the field, thus avoiding problems in the effective management of insect populations.

DIRCEU, PRATISSOLI; THIAGO G., KLOSS; FERNANDO D., ZINGER; JOSÉ R. DE, CARVALHO; ULYSSES R., VIANNA; JOÃO P.P., PAES.

2014-03-01

346

Does mating interfere in the biological characteristics of a population of Trichogramma pretiosum?  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Trichogramma spp. são parasitoides utilizados na regulação de populações de insetos que podem causar danos econômicos. Para que esses tenham bom desempenho é essencial o conhecimento de algumas de suas características biológicas. O objetivo deste trabalho foi avaliar se o acasalamento interfere nas [...] características biológicas de uma população de Trichogramma pretiosum coletada em campo. Em todos os experimentos, grupos de fêmeas acasaladas e não acasaladas foram utilizados. Além disso, foi verificada a interferência do acasalamento nas características biológicas dos descendentes. Foi constatado que o acasalamento é capaz de alterar o parasitismo e a longevidade das fêmeas genitoras, além de alterar a longevidade entre os descendentes, porém, uma vez parasitados, os ovos se desenvolvem normalmente, apresentando viabilidade e número de descendentes similares aos das fêmeas não acasaladas. Verificamos ainda, que a população de T. pretiosum coletada em campo apresentou indivíduos com características reprodutivas telítocas e arrenótocas. Esse fato ressalta a importância de investigações cuidadosas sobre o modo de reprodução das populações coletadas em campo, evitando assim problemas de eficiência no manejo de populações de insetos. Abstract in english Trichogramma spp. are parasitoids used in the regulation of insect populations that can cause economic damage. In order to ensure good performance, understanding some of their biological characteristics is essential. The objective of this study is to evaluate whether mating interferes with the biol [...] ogical characteristics of a population of Trichogramma pretiosum collected in the field. In all experiments, groups of mated and unmated females were used. We also verified any interference from mating on the biological characteristics of the offspring. We found that mating can alter the parasitism and longevity of genitor females, in addition to changing longevity among the descendants, but once parasitized, the eggs develop normally, showing similar emergence percentage and number of offspring as those from unmated females. In addition, we verified that the population of T. pretiosum collected in the field presented individuals with reproductive thelytokous and arrhenotokous characteristics. This fact highlights the importance of careful investigation on the reproduction mode of populations collected in the field, thus avoiding problems in the effective management of insect populations.

DIRCEU, PRATISSOLI; THIAGO G., KLOSS; FERNANDO D., ZINGER; JOSÉ R. DE, CARVALHO; ULYSSES R., VIANNA; JOÃO P.P., PAES.

347

Comparative evaluation and its implications for mate choice.  

Science.gov (United States)

Experiments on decision making by humans show that the choices that we make can be very labile. The magnitude of our preferences, and even our rank ordering of options, can vary according to the number and type of alternatives available for comparison. This apparent irrationality has been argued to result from our use of decision heuristics that have evolved to enable us to choose quickly and efficiently between options differing in multiple attributes. Here, we argue that, because there is also selective pressure for animals to make mating decisions quickly, and because potential mates also differ in multiple attributes, similar decision heuristics might have evolved for mate choice. Following this reasoning, the attractiveness of a given mate will depend on the others with whom he or she is being compared, rather than being an absolute function of his or her underlying quality. We describe some of the ramifications of such comparative evaluation, and argue that it could offer new insights into some of the biggest outstanding problems in mate choice and sexual selection. PMID:16701454

Bateson, Melissa; Healy, Susan D

2005-12-01

348

Genetic variation in social influence on mate preferences.  

Science.gov (United States)

Patterns of phenotypic variation arise in part from plasticity owing to social interactions, and these patterns contribute, in turn, to the form of selection that shapes the variation we observe in natural populations. This proximate-ultimate dynamic brings genetic variation in social environments to the forefront of evolutionary theory. However, the extent of this variation remains largely unknown. Here, we use a member of the Enchenopa binotata species complex of treehoppers (Hemiptera: Membracidae) to assess how mate preferences are influenced by genetic variation in the social environment. We used full-sibling split-families as 'treatment' social environments, and reared focal females alongside each treatment family, describing the mate preferences of the focal females. With this method, we detected substantial genetic variation in social influence on mate preferences. The mate preferences of focal females varied according to the treatment families along with which they grew up. We discuss the evolutionary implications of the presence of such genetic variation in social influence on mate preferences, including potential contributions to the maintenance of genetic variation, the promotion of divergence, and the adaptive evolution of social effects on fitness-related traits. PMID:23698010

Rebar, Darren; Rodríguez, Rafael L

2013-07-22

349

Genetic Analysis of Mate Discrimination in Drosophila simulans  

Science.gov (United States)

Courtship is an elaborate behavior that conveys information about the identity of animal species and suitability of individual males as mates. In Drosophila, there is extensive evidence that females are capable of evaluating and comparing male courtships, and accepting or rejecting males as mates. These relatively simple responses minimize random sexual encounters involving subpar conspecific males and heterospecific males, and over generations can potentially select novel physical and behavioral traits. Despite its evolutionary and behavioral significance, little is still known about the genes involved in mating choice and how choices for novel males and females arise during evolution. D. simulans and D. sechellia are two recently diverged species of Drosophila in which females have a preference for conspecific males. Here we analyzed a total of 1,748 F2 hybrid females between these two species and found a small number of dominant genes controlling the preference for D. simulans males. We also mapped two redundant X-linked loci of mating choice, Macho-XA and Macho-XB, and show that neither one is required for female attractiveness. Together, our results reveal part of the genetic architecture that allows D. simulans females to recognize, mate and successfully generate progenies with D. simulans males. PMID:23888855

Chu, Y.; Yang, E.; Schinaman, J.M.; Chahda, J.S.; Sousa-Neves, R.

2013-01-01

350

Do assortative preferences contribute to assortative mating for adiposity?  

Science.gov (United States)

Assortative mating for adiposity, whereby levels of adiposity in romantic partners tend to be positively correlated, has implications for population health due to the combined effects of partners' levels of adiposity on fertility and/or offspring health. Although assortative preferences for cues of adiposity, whereby leaner people are inherently more attracted to leaner individuals, have been proposed as a factor in assortative mating for adiposity, there have been no direct tests of this issue. Because of this, and because of recent work suggesting that facial cues of adiposity convey information about others' health that may be particularly important for mate preferences, we tested the contribution of assortative preferences for facial cues of adiposity to assortative mating for adiposity (assessed from body mass index, BMI) in a sample of romantic couples. Romantic partners' BMIs were positively correlated and this correlation was not due to the effects of age or relationship duration. However, although men and women with leaner partners showed stronger preferences for cues of low levels of adiposity, controlling for these preferences did not weaken the correlation between partners' BMIs. Indeed, own BMI and preferences were uncorrelated. These results suggest that assortative preferences for facial cues of adiposity contribute little (if at all) to assortative mating for adiposity. PMID:24168811

Fisher, Claire I; Fincher, Corey L; Hahn, Amanda C; Little, Anthony C; DeBruine, Lisa M; Jones, Benedict C

2014-11-01

351

On sex, mate selection and the red queen.  

Science.gov (United States)

The widespread occurrence of sexual reproduction despite the two-fold disadvantage of producing males, is still an unsolved mystery in evolutionary biology. One explanatory theory, called the "Red Queen" hypothesis, states that sex is an adaptation to escape from parasites. A more recent hypothesis, the mate selection hypothesis, assumes that non-random mating, possible only with sex, accelerates the evolution of beneficial traits. This paper tests these two hypotheses, using an agent-based or "micro-analytic" evolutionary algorithm where host-parasite interaction is simulated adhering to biological reality. While previous simpler models testing the "Red Queen" hypothesis considered mainly haploid hosts, stable population density, random mating and simplified expression of fitness, our more realistic model allows diploidy, mate selection, live history constraints and variable population densities. Results suggest that the Red Queen hypothesis is not valid for more realistic evolutionary scenarios and that each of the two hypotheses tested seem to explain partially but not exhaustively the adaptive value of sex. Based on the results we suggest that sexual populations in nature should avoid both, maximizing outbreeding or maximizing inbreeding and should acquire mate selection strategies which favour optimal ranges of genetic mixing in accordance with environmental challenges. PMID:10419756

Ochoa, G; Jaffé, K

1999-07-01

352

Human nonindependent mate choice: is model female attractiveness everything?  

Science.gov (United States)

Following two decades of research on non-human animals, there has recently been increased interest in human nonindependent mate choice, namely the ways in which choosing women incorporate information about a man's past or present romantic partners ('model females') into their own assessment of the male. Experimental studies using static facial images have generally found that men receive higher desirability ratings from female raters when presented with attractive (compared to unattractive) model females. This phenomenon has a straightforward evolutionary explanation: the fact that female mate value is more dependent on physical attractiveness compared to male mate value. Furthermore, due to assortative mating for attractiveness, men who are paired with attractive women are more likely to be of high mate value themselves. Here, we also examine the possible relevance of model female cues other than attractiveness (personality and behavioral traits) by presenting video recordings of model females to a set of female raters. The results confirm that the model female's attractiveness is the primary cue. Contrary to some earlier findings in the human and nonhuman literature, we found no evidence that female raters prefer partners of slightly older model females. We conclude by suggesting some promising variations on the present experimental design. PMID:22947636

Vakirtzis, Antonios; Roberts, S Craig

2012-01-01

353

The evolution of phenotypes and genetic parameters under preferential mating.  

Science.gov (United States)

This article extends and adds more realism to Lande's analytical model for evolution under mate choice by using individual-based simulations in which females sample a finite number of males and the genetic architecture of the preference and preferred trait evolves. The simulations show that the equilibrium heritabilities of the preference and preferred trait and the genetic correlation between them (r G), depend critically on aspects of the mating system (the preference function, mode of mate choice, choosiness, and number of potential mates sampled), the presence or absence of natural selection on the preferred trait, and the initial genetic parameters. Under some parameter combinations, preferential mating increased the heritability of the preferred trait, providing a possible resolution for the lek paradox. The Kirkpatrick-Barton approximation for r G proved to be biased downward, but the realized genetic correlations were also low, generally selection in the simulations, except where preferences were relative and the preferred trait was subject to natural selection. In these cases, runaways were over- or underestimated, depending on the number of males sampled. We conclude that rapid coevolution of preferences and preferred traits is unlikely in natural populations, but that the parameter combinations most conducive to it are most likely to occur in lekking species. PMID:25077025

Roff, Derek A; Fairbairn, Daphne J

2014-07-01

354

Aggregation and mating success of Capnodis tenebrionis (Coleoptera: Buprestidae).  

Science.gov (United States)

An understanding of the relative importance of extrinsic and intrinsic factors in determining the potential distribution and mating success of individuals is critical for the successful monitoring and management of pest species. Using a combination of field observations and a caged field experiment, we explored the roles of environmental and individual variation on the formation of mating aggregations and mating success in the buprestid beetle Capnodis tenebrionis (Linnaeus, 1767), a pest species of stone fruit trees. Our field observations revealed that the formation of aggregations is influenced by a range of environmental factors including temperature, photoperiod, and population density. However, aggregations were not at random and were more likely to occur on the section of the plant with highest incidence of solar radiation and thus higher temperatures. Data from our experiment with caged beetles in the field further indicate that the reproductive behavior of this species varies with temperature. The probability of a successful mating occurring was also positively related to both male and female size. Females of C. tenebrionis mate several times over a 4-h period, but generally not with the same male. Information obtained from these studies is useful to define the most appropriate time for pest control, especially adopting strategies that interfere with reproduction. PMID:23955847

Bonsignore, Carmelo Peter; Jones, Therésa Melanie

2014-04-01

355

Behavioural determinants of gene flow in malaria vector populations: Anopheles gambiae males select large females as mates  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Plasmodium-refractory mosquitoes are being rapidly developed for malaria control but will only succeed if they can successfully compete for mates when released into the wild. Pre-copulatory behavioural traits maintain genetic population structure in wild mosquito populations and mating barriers have foiled previous attempts to control malaria vectors through sterile male release. Methods Varying numbers of virgin male and female Anopheles gambiae Giles, from two strains of different innate sizes, were allowed to mate under standardized conditions in laboratory cages, following which, the insemination status, oviposition success and egg batch size of each female was assessed. The influence of male and female numbers, strain combination and female size were determined using logistic regression, correlation analysis and a simple mechanistic model of male competition for females. Results Male An. gambiae select females on the basis of size because of much greater fecundity among large females. Even under conditions where large numbers of males must compete for a smaller number of females, the largest females are more likely to become inseminated, to successfully oviposit and to produce large egg batches. Conclusions Sexual selection, on the basis of size, could either promote or limit the spread of malaria-refractory genes into wild populations and needs to be considered in the continued development and eventual release of transgenic vectors. Fundamental studies of behavioural ecology in malaria vectors such as An. gambiae can have important implications for malaria control and should be prioritised for more extensive investigation in the future.

Yan G

2002-08-01

356

Evaluation of phenolic compounds in mate (Ilex paraguariensis) processed by gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

The radiation food processing has been demonstrating great effectiveness in the attack of pathogenic agents, while little compromising nutritional value and sensorial properties of foods. The mate (Ilex paraguariensis), widely consumed product in South America, generally in the form of infusions with hot or cold water, calls of chimarrao or terere, it is cited in literature as one of the best sources phenolic compounds. The antioxidants action of these constituent has been related to the protection of the organism against the free radicals, generated in alive, currently responsible for the sprouting of some degenerative illness as cancer, arteriosclerosis, rheumatic arthritis and cardiovascular clutters among others. The objective of that work was to evaluate the action of the processing for gamma radiation in phenolic compounds of terere beverage in the doses of 0, 3, 5, 7 and 10 kGy. The observed results do not demonstrate significant alterations in phenolic compounds of terere beverage processed by gamma radiation.

Furgeri, C.; Nunes, T.C.F.; Fanaro, G.B. [Instituto de Pesquisas Energeticas Nucleares, IPEN-CNEN/SP, Centro de Tecnologia das Radiacoes-Laboratory de Deteccao de Alimentos Irradiados, Av. Professor Lineu Prestes, 2242, Cidade Universitaria, CEP: 05508-900 Sao Paulo (Brazil); Souza, M.F.F.; Bastos, D.H.M. [Faculdade de Saude Publica, FSP/USP, Departamento de Nutricao-Av. Dr. Arnaldo, 715, CEP: 01246-904 Sao Paulo (Brazil); Villavicencio, A.L.C.H. [Instituto de Pesquisas Energeticas Nucleares, IPEN-CNEN/SP, Centro de Tecnologia das Radiacoes-Laboratory de Deteccao de Alimentos Irradiados, Av. Professor Lineu Prestes, 2242, Cidade Universitaria, CEP: 05508-900 Sao Paulo (Brazil)], E-mail: villavic@ipen.br

2009-07-15

357

Love makes smell blind: mating suppresses pheromone attraction in Drosophila females via Or65a olfactory neurons.  

Science.gov (United States)

In Drosophila, the male sex pheromone cis-vaccenyl acetate (cVA) elicits aggregation and courtship, through the odorant receptor Or67d. Long-lasting exposure to cVA suppresses male courtship, via a second channel, Or65a. In females, the role of Or65a has not been studied. We show that, shortly after mating, Drosophila females are no longer attracted to cVA and that activation of olfactory sensory neurons (OSNs) expressing Or65a generates this behavioral switch: when silencing Or65a, mated females remain responsive to cVA. Neurons expressing Or67d converge into the DA1 glomerulus in the antennal lobe, where they synapse onto projection neurons (PNs), that connect to higher neural circuits generating the attraction response to cVA. Functional imaging of these PNs shows that the DA1 glomerulus is inhibited by simultaneous activation of Or65a OSNs, which leads to a suppression of the attraction response to cVA. The behavioral role of postmating cVA exposure is substantiated by the observation that matings with starved males, which produce less cVA, do not alter the female response. Moreover, exposure to synthetic cVA abolishes attraction and decreases sexual receptivity in unmated females. Taken together, Or65a mediates an aversive effect of cVA and may accordingly regulate remating, through concurrent behavioral modulation in males and females. PMID:25406576

Lebreton, Sébastien; Grabe, Veit; Omondi, Aman B; Ignell, Rickard; Becher, Paul G; Hansson, Bill S; Sachse, Silke; Witzgall, Peter

2014-01-01

358

Body size, mating success and advantage of large flies in Drosophila bipectinata species complex.  

Science.gov (United States)

Mating success of large and small flies of Drosophila malerkotliana and D. bipectinata was studied using multiple, male and female choice methods. In multiple choice method the large male mated with large female and small male paired with small female. In female choice method, large male was successful in mating with female irrespective of its size while in male choice method, preferential mating occurred between large male and large female as well as small male and small female. The consequence of such non-random mating in the presence of male rivarly and preferential mating has been discussed. PMID:9567772

Krishna, M S; Hegde, S N

1997-12-01

359

The study and analysis of the mating behavior and sound production of male cicada Psalmocharias alhageos (Kol.) (Homoptera:Cicadidae) to make disruption in mating.  

Science.gov (United States)

Psalmocharias alhageos is an important pest of vine in most parts of Iran, Afghanistan, Pakistan, southern areas of Russia, Turkey and Iraq. This cicada is spread in most provinces in Iran such as Esfahan, Hamedan, Qazvin, Markazi, Lorestan, Qom, Kerman, Tehran and Kordestan. In addition to vine, this insect damages some other fruit trees, such as apple, sour cherry, quince, peach, pomegranate and pear trees and some non-fruit trees, namely white poplar, ash, elm, eglantine, silk and black poplar trees. The nymphs of cicada damage the trees by feeding on root, adult insects on young bud and by oviposition under branch barks. Nourishing root by nymph leads to the weakness of the tree and hinder its growth. The high density oviposition of adult insects inside young barks causes withering of branches. The resulted damage on vine products is 40% which is one of the most important factors in product reduction in vineyard. This research was conducted in Takestan in Qazvin. It was conducted for the first time to study the behaviors of the mates of this vine cicada in order to manage it. Two systems were used to record the sound of male cicada called analog voice-recorder and digital voice recorder. To analyze the recorded sound of the male cicada we used of spectrum analyzer, digital storage oscilloscope and protens 7 computer softwares. We could call the attention of natural enemies an disturb the male insect's attracting sound by producing natural and artificial sound in the range of 1-6 kHz in two different ripeness status of the fruits and could prevent mating and oviposition of female cicadas. PMID:19266919

Zamanian, H; Mehdipour, M; Ghaemi, N

2008-09-01

360

The Study and Analysis of the Mating Behavior and Sound Production of Male Cicada Psalmocharias alhageos (Kol. (Homoptera:Cicadidae to Make Disruption in Mating  

Directory of Open Access Journals (Sweden)

Full Text Available Psalmocharias alhageos is an important pest of vine in most parts of Iran, Afghanistan, Pakistan, southern areas of Russia, Turkey and Iraq. This cicada is spread in most provinces in Iran such as Esfahan, Hamedan, Qazvin, Markazi, Lorestan, Qom, Kerman, Tehran and Kordestan. In addition to vine, this insect damages some other fruit trees, such as apple, sour cherry, quince, peach, pomegranate and pear trees and some non-fruit trees, namely white poplar, ash, elm, eglantine, silk and black poplar trees. The nymphs of cicada damage the trees by feeding on root, adult insects on young bud and by oviposition under branch barks. Nourishing root by nymph leads to the weakness of the tree and hinder its growth. The high density oviposition of adult insects inside young barks causes withering of branches. The resulted damage on vine products is 40% which is one of the most important factors in product reduction in vineyard. This research was conducted in Takestan in Qazvin. It was conducted for the first time to study the behaviors of the mates of this vine cicada in order to manage it. Two systems were used to record the sound of male cicada called analog voice-recorder and digital voice recorder. To analyze the recorded sound of the male cicada we used of spectrum analyzer, digital storage oscilloscope and protens 7 computer softwares. We could call the attention of natural enemies an disturb the male insect`s attracting sound by producing natural and artificial sound in the range of 1-6 kHz in two different ripeness status of the fruits and could prevent mating and oviposition of female cicadas.

H. Zamanian

2008-01-01

 
 
 
 
361

Alterações agudas dos níveis de neurotransmissores em corpo estriado de ratos jovens após estado epiléptico induzido por pilocarpina Acute alterations of neurotransmitters levels in striatum of young rat after pilocarpine-induced status epilepticus  

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Full Text Available Altas doses de agonista colinérgico muscarínico, pilocarpina, produzem alterações comportamentais, convulsões e estado epiléptico em ratos. O objetivo desse estudo foi verificar as alterações nas concentrações dos neurotransmissores em corpo estriado de ratos em desenvolvimento após estado epiléptico induzido pela pilocarpina. Ratas Wistar foram tratadas com uma única dose de pilocarpina (400mg/Kg; s.c.. Controles receberam salina. A concentração dos neurotransmissores foi determinada através do HPLC, no corpo estriado de ratos que no período de observação de 1 e 24h desencadearam estado epiléptico e não sobreviveram à fase aguda do quadro convulsivo. Foi observada redução nos níveis de dopamina, serotonina, ácido dihidroxifenilacético, ácido 5-hidroxiindolacético, e aumento no ácido 4-hidroxi-3-metoxi-fenilacético. Os resultados mostraram que a ativação do sistema colinérgico pode interagir com os sistemas dopaminérgico e serotonérgico nos mecanismos referentes à fase aguda do processo convulsivo.High doses of the muscarinic cholinergic agonist, pilocarpine, result in behavioural changes, seizures and status epilepticus in rats. The purpose of the present work is to invetigate the striatal neurotransmissors level in young rats after status epilepticus induced by pilocarpine. Wistar rats were treated with a single dose of pilocarpine (400mg/Kg; s.c.. Controls received saline. Young animals were closed observed for behavioural changes during 1 and 24h. In these periods, the animals that developed status epilepticus and didn't survive this acute phase of seizures had the brains removed and striatal neurotransmissors level determined by HPLC. The concentration of dopamine, serotonine, dihydroxyphenylacetic acid, 5-hydroxyindolacetic acid was reduced and an increase in 4-hydroxy-3-methoxy-phenylacetic acid was observed. These results suggest that cholinergic activation can interage with dopaminergic and serotonergic systems in acute phase of the convulsive process in immature striatum.

Rivelilson Mendes de Freitas

2003-06-01

362

Alterações agudas dos níveis de neurotransmissores em corpo estriado de ratos jovens após estado epiléptico induzido por pilocarpina / Acute alterations of neurotransmitters levels in striatum of young rat after pilocarpine-induced status epilepticus  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Altas doses de agonista colinérgico muscarínico, pilocarpina, produzem alterações comportamentais, convulsões e estado epiléptico em ratos. O objetivo desse estudo foi verificar as alterações nas concentrações dos neurotransmissores em corpo estriado de ratos em desenvolvimento após estado epiléptic [...] o induzido pela pilocarpina. Ratas Wistar foram tratadas com uma única dose de pilocarpina (400mg/Kg; s.c.). Controles receberam salina. A concentração dos neurotransmissores foi determinada através do HPLC, no corpo estriado de ratos que no período de observação de 1 e 24h desencadearam estado epiléptico e não sobreviveram à fase aguda do quadro convulsivo. Foi observada redução nos níveis de dopamina, serotonina, ácido dihidroxifenilacético, ácido 5-hidroxiindolacético, e aumento no ácido 4-hidroxi-3-metoxi-fenilacético. Os resultados mostraram que a ativação do sistema colinérgico pode interagir com os sistemas dopaminérgico e serotonérgico nos mecanismos referentes à fase aguda do processo convulsivo. Abstract in english High doses of the muscarinic cholinergic agonist, pilocarpine, result in behavioural changes, seizures and status epilepticus in rats. The purpose of the present work is to invetigate the striatal neurotransmissors level in young rats after status epilepticus induced by pilocarpine. Wistar rats were [...] treated with a single dose of pilocarpine (400mg/Kg; s.c.). Controls received saline. Young animals were closed observed for behavioural changes during 1 and 24h. In these periods, the animals that developed status epilepticus and didn't survive this acute phase of seizures had the brains removed and striatal neurotransmissors level determined by HPLC. The concentration of dopamine, serotonine, dihydroxyphenylacetic acid, 5-hydroxyindolacetic acid was reduced and an increase in 4-hydroxy-3-methoxy-phenylacetic acid was observed. These results suggest that cholinergic activation can interage with dopaminergic and serotonergic systems in acute phase of the convulsive process in immature striatum.

Rivelilson Mendes de, Freitas; Francisca Cléa Florenço de, Sousa; Silvânia Maria Mendes, Vasconcelos; Glauce Socorro Barros, Viana; Marta Maria de França, Fonteles.

363

Irradiation detection of coffee mate by electron spin resonance (ESR)  

Energy Technology Data Exchange (ETDEWEB)

Un-irradiated coffee mate samples do not exhibit any ESR signal. However, the samples exposed to UV and gamma radiation exhibit an ESR singlet and a large unresolved ESR signal, respectively. The dose-response curves of the samples exposed to UV and gamma radiations were found to be described well by an exponential and linear functions, respectively. Variable temperature and fading studies at room temperature showed that the radiation-induced radicals in coffee mate sample are very sensitive to temperature. The discrimination between un-irradiated and irradiated coffee mate samples can be done just comparing their ESR spectra. However, determination of the radiation dose received by the sample cannot be possible because of the fast decay of signal intensity at room temperature.

Ozsayin, Fulya [Physics Engineering Department, Hacettepe University, 06800 Ankara (Turkey); Polat, Mustafa, E-mail: polat@hacettepe.edu.t [Physics Engineering Department, Hacettepe University, 06800 Ankara (Turkey)

2011-06-15

364

Irradiation detection of coffee mate by electron spin resonance (ESR)  

International Nuclear Information System (INIS)

Un-irradiated coffee mate samples do not exhibit any ESR signal. However, the samples exposed to UV and gamma radiation exhibit an ESR singlet and a large unresolved ESR signal, respectively. The dose-response curves of the samples exposed to UV and gamma radiations were found to be described well by an exponential and linear functions, respectively. Variable temperature and fading studies at room temperature showed that the radiation-induced radicals in coffee mate sample are very sensitive to temperature. The discrimination between un-irradiated and irradiated coffee mate samples can be done just comparing their ESR spectra. However, determination of the radiation dose received by the sample cannot be possible because of the fast decay of signal intensity at room temperature.

365

Diffusion approximation of a multilocus model with assortative mating  

CERN Document Server

To understand the effect of non-random mating on the genetic evolution of a population, we consider a finite population in which each individual is defined by a sequence of n diallelic loci. We assume that the population evolves according to a Moran model with assortative mating, recombination and mutation. Under weak assortative mating, loose linkage and low mutation rates, we obtain a class of diffusion approximations for allelic frequencies. We present some features of the limiting diffusions (in particular their boundary behaviour and conditions under which the allelic frequencies at different loci evolve independently). If mutation rates are strictly positive then the limiting diffusions are reversible and, under some assumptions, the critical points of the stationary density can be characterised.

Etheridge, Alison M

2011-01-01

366

Mating activity of gamma irradiated codling moth, Laspeyresia pomonella (L.)  

International Nuclear Information System (INIS)

Mating of 30-krad treated codling moths, Laspeyresia pomonella, under field cage conditions occurred mainly at temperatures ranging from 14 to 200C. Irradiation applied to diet-reared moths produced neither an apparent shift in the time (hours) of copulation nor a decrease of the mating activity. However, a significant reduction in the mating ability was induced by Calco Oil Red added to the larval diet, and also by handling and transporting the moths about 140 km to the irradiation facilities. The morning time was found to be the best time to release irradiated moths in the field. Males reared on thinning apples were two times more active sexually than ones reared on an artificial medium. (author)

367

Social exclusion and female mating behavior: rejected women show strategic enhancement of short-term mating interest.  

Science.gov (United States)

Because cost asymmetries in sexual reproduction have historically enabled women to exchange sexual access for other resources, including social resources, we tested the possibility that social exclusion would lead women to display an elevated preference for short-term mating strategies in the service of reaffiliation. In Study 1, women were given false feedback to manipulate social inclusion or exclusion prior to indicating their endorsement of short and long-term mating behaviors. Socially excluded women indicated greater interest in short-term mating and reduced interest in long-term mating. In Study 2, women wrote about a social inclusion, social exclusion, or control experience and then indicated their preference for different male body types. Women in the social exclusion condition preferred more muscular male partners--a pattern of preference typical of short-term mating--than women in the other conditions. Collectively, these results are consistent with a social exchange theory of women's sexual behavior following social exclusion. PMID:22947679

Sacco, Donald F; Young, Steven G; Brown, Christina M; Bernstein, Michael J; Hugenberg, Kurt

2012-01-01

368

Genetic basis for MHC-dependent mate choice.  

Science.gov (United States)

Genes in the major histocompatibility complex (MHC), best known for their role in immune recognition and transplantation success, are also involved in modulating mate choice in mice. Early studies with inbred, congenic mouse lines showed that mate choice tended to favor nonself MHC types. A similar phenomenon was demonstrated with semi-wild mice as well. Subsequent studies showed that, rather than nonself choices, it was more accurate to say that mice chose nonparental MHC types for mates since preferences for nonself could be reversed if mice were fostered from birth on parents with nonself MHC types. Other studies have demonstrated that parent-offspring recognition is also regulated by MHC-determined signals suggesting that this system is one of general importance for mouse behavior. Many studies have now demonstrated that volatile mouse body odors are regulated by MHC genes and it is presumably these odor differences that underlie mate choice and familial recognition. Recent studies have shown that many odorants are controlled by the MHC but the mechanism by which MHC genes exert their influence has not been identified. Surprisingly, not only are volatile body odors influenced by MHC genes but so too are nonvolatile signals. Peptides bound to the MHC protein may also function in individual recognition. The extent to which this system is involved in mate choice of other species is unclear although there are some suggestive studies. Indeed, there is tentative evidence that MHC differences, presumably acting via odor changes, may influence human partner selection. Further studies should clarify both the mechanism underlying MHC influence on body odors as well as the generality of their importance in mate selection. PMID:17888797

Yamazaki, Kunio; Beauchamp, Gary K

2007-01-01

369

Blackmailing: the keystone in the human mating system  

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Full Text Available Abstract Background The human mating system is characterized by bi-parental care and faithful monogamy is highly valued in most cultures. Marriage has evolved as a social institution and punishment for extra pair mating (EPM or adultery is common. However, similar to other species with bi-parental care, both males and females frequently indulge in EPM in secrecy since it confers certain gender specific genetic benefits. Stability of faithful monogamy is therefore a conundrum. We model human mating system using game theory framework to study the effects of factors that can stabilize or destabilize faithful committed monogamy. Results Although mate guarding can partly protect the genetic interests, we show that it does not ensure monogamy. Social policing enabled by gossiping is another line of defense against adultery unique to humans. However, social policing has a small but positive cost to an individual and therefore is prone to free riding. We suggest that since exposure of adultery can invite severe punishment, the policing individuals can blackmail opportunistically whenever the circumstances permit. If the maximum probabilistic benefit of blackmailing is greater than the cost of policing, policing becomes a non-altruistic act and stabilizes in the society. We show that this dynamics leads to the coexistence of different strategies in oscillations, with obligate monogamy maintained at a high level. Deletion of blackmailing benefit from the model leads to the complete disappearance of obligate monogamy. Conclusions Obligate monogamy can be maintained in the population in spite of the advantages of EPM. Blackmailing, which makes policing a non-altruistic act, is crucial for the maintenance of faithful monogamy. Although biparental care, EPM, mate guarding and punishment are shared by many species, gossiping and blackmailing make the human mating system unique.

Watve Milind G

2011-11-01

370

Emergence of Polymorphic Mating Strategies in Robot Colonies  

Science.gov (United States)

Polymorphism has fascinated evolutionary biologists since the time of Darwin. Biologists have observed discrete alternative mating strategies in many different species. In this study, we demonstrate that polymorphic mating strategies can emerge in a colony of hermaphrodite robots. We used a survival and reproduction task where the robots maintained their energy levels by capturing energy sources and physically exchanged genotypes for the reproduction of offspring. The reproductive success was dependent on the individuals' energy levels, which created a natural trade-off between the time invested in maintaining a high energy level and the time invested in attracting mating partners. We performed experiments in environments with different density of energy sources and observed a variety in the mating behavior when a robot could see both an energy source and a potential mating partner. The individuals could be classified into two phenotypes: 1) forager, who always chooses to capture energy sources, and 2) tracker, who keeps track of potential mating partners if its energy level is above a threshold. In four out of the seven highest fitness populations in different environments, we found subpopulations with distinct differences in genotype and in behavioral phenotype. We analyzed the fitnesses of the foragers and the trackers by sampling them from each subpopulation and mixing with different ratios in a population. The fitness curves for the two subpopulations crossed at about 25% of foragers in the population, showing the evolutionary stability of the polymorphism. In one of those polymorphic populations, the trackers were further split into two subpopulations: (strong trackers) and (weak trackers). Our analyses show that the population consisting of three phenotypes also constituted several stable polymorphic evolutionarily stable states. To our knowledge, our study is the first to demonstrate the emergence of polymorphic evolutionarily stable strategies within a robot evolution framework. PMID:24717898

Elfwing, Stefan; Doya, Kenji

2014-01-01

371

Genetic determinants of mate recognition in Brachionus manjavacas (Rotifera  

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Full Text Available Abstract Background Mate choice is of central importance to most animals, influencing population structure, speciation, and ultimately the survival of a species. Mating behavior of male brachionid rotifers is triggered by the product of a chemosensory gene, a glycoprotein on the body surface of females called the mate recognition pheromone. The mate recognition pheromone has been biochemically characterized, but little was known about the gene(s. We describe the isolation and characterization of the mate recognition pheromone gene through protein purification, N-terminal amino acid sequence determination, identification of the mate recognition pheromone gene from a cDNA library, sequencing, and RNAi knockdown to confirm the functional role of the mate recognition pheromone gene in rotifer mating. Results A 29 kD protein capable of eliciting rotifer male circling was isolated by high-performance liquid chromatography. Two transcript types containing the N-terminal sequence were identified in a cDNA library; further characterization by screening a genomic library and by polymerase chain reaction revealed two genes belonging to each type. Each gene begins with a signal peptide region followed by nearly perfect repeats of an 87 to 92 codon motif with no codons between repeats and the final motif prematurely terminated by the stop codon. The two Type A genes contain four and seven repeats and the two Type B genes contain three and five repeats, respectively. Only the Type B gene with three repeats encodes a peptide with a molecular weight of 29 kD. Each repeat of the Type B gene products contains three asparagines as potential sites for N-glycosylation; there are no asparagines in the Type A genes. RNAi with Type A double-stranded RNA did not result in less circling than in the phosphate-buffered saline control, but transfection with Type B double-stranded RNA significantly reduced male circling by 17%. The very low divergence between repeat units, even at synonymous positions, suggests that the repeats are kept nearly identical through a process of concerted evolution. Information-rich molecules like surface glycoproteins are well adapted for chemical communication and aquatic animals may have evolved signaling systems based on these compounds, whereas insects use cuticular hydrocarbons. Conclusion Owing to its critical role in mating, the mate recognition pheromone gene will be a useful molecular marker for exploring the mechanisms and rates of selection and the evolution of reproductive isolation and speciation using rotifers as a model system. The phylogenetic variation in the mate recognition pheromone gene can now be studied in conjunction with the large amount of ecological and population genetic data being gathered for the Brachionus plicatilis species complex to understand better the evolutionary drivers of cryptic speciation.

Kubanek Julia

2009-09-01

372

Mating system and size advantage of male mating in the protogynous swamp eel Monopterus albus with paternal care.  

Science.gov (United States)

In fish with paternal care, protogynous sex change (female to male) is rare and has only been reported from species with haremic polygyny. The swamp eel, Monopterus albus, is a protogynous fish with paternal care, but little is known about its mating system. To understand protogyny in this species, we examined the mating system and male size advantage in mating in M. albus under semi-natural condition. Females swam over wide ranges and visited multiple male nests. Males defended a narrow territory around nests against other males that approached nests; at these nests, males courted and accepted visiting females. After spawning inside nests, caring males continued to perform courtship activities, and multiple breeding was observed. These observations suggest that the M. albus mating system is male-territory-visiting (MTV)-polygamy. Larger males had nests, and mated more frequently compared with small males. Because small initial males of this species are not found in nature, and because M. albus does not engage in sneaking tactics, larger nesting males do not suffer from reproductive parasitism. Thus, protogyny in this fish is likely consistent with the predictions of the size-advantage model. Biting attacks by territorial males of this predatory fish seriously wounded intruding males, occasionally resulting in the death of the intruder. We discuss the possibility that sexual differences in mortality rates in small fish may facilitate the evolution of protogyny in this species. Protogyny of the swamp eel is, to our knowledge, the first example of an MTV-polygamous mating system in a fish with paternal care. PMID:21557660

Matsumoto, Seiji; Takeyama, Tomohiro; Ohnishi, Nobuhiro; Kohda, Masanori

2011-05-01

373

46 CFR 11.462 - Endorsements for master or mate of uninspected fishing industry vessels.  

Science.gov (United States)

...master or mate of uninspected fishing industry vessels. 11.462 Section...master or mate of uninspected fishing industry vessels. (a) This section...documented to engage in the fishing industry, with the exception of:...

2010-10-01

374

Light wavelength dependency of mating activity in the drosophila melanogaster species subgroup  

International Nuclear Information System (INIS)

The action spectra of mating activity among the six species of the Drosophila melanogaster species subgroup were compared to understand how light wavelength affects mating activity. The species fell into three groups with respect to the action spectrum of mating activity. We chose one representative species from each of the three types for detailed study: D. melanogaster, D. sechellia and D. yakuba. The mating activities were investigated under three different light intensities of three monochromatic lights stimulus. Each species showed a unique spectral and intensity response. To know the evolutionary meaning of the light wavelength dependency of mating activity, we superimposed the type of action spectrum of mating activity in these six species on a cladogram. Mating inhibition under UV was conserved in evolution among these species. Furthermore we clarified that D. melanogaster showed low mating activity under UV because males courted less under UV. (author)

375

Occurrence of polycyclic aromatic hydrocarbons throughout the processing stages of erva-mate (Ilex paraguariensis).  

Science.gov (United States)

The presence of polycyclic aromatic hydrocarbons (PAHs) in mate (Ilex paraguariensis) is believed to be due to the degradation of mate compounds and the burning of wood during the "sapeco" (rapid drying process) and the final drying steps, which are the most important processing stages in mate production. Due to the high toxicity of these compounds, studies on their presence in mate are extremely important. The aim of this study was to evaluate PAH levels in mate throughout the processing stages of its production. The PAHs were measured in samples collected at different stages of mate processing. Total PAHs content ranged widely (443-9001 microg/kg) in the samples, with the highest PAHs levels recorded during the mate drying step. The results indicate that the processing method currently used in mate production may lead to an increase in PAHs levels in the final product. PMID:20349373

Vieira, Manoela Alano; Maraschin, Marcelo; Rovaris, Angela Angeloni; Amboni, Renata Dias de Mello Castanho; Pagliosa, Cristiane Manfé; Xavier, José Júnior Mendonca; Amante, Edna Regina

2010-06-01

376

Instrumental and Expressive Values in Mate Selection of Black and White College Students  

Science.gov (United States)

This study investigated differences between black and white college students' values concerning mate selection. The relative importance of 12 desired traits in a potential mate, divided equally into instrumental and expressive traits, is examined. Results are discussed. (Author)

Melton, Willie; Thomas, Darwin L.

1976-01-01

377

Using Dissortative Mating Genetic Algorithms to Track the Extrema of Dynamic Deceptive Functions  

CERN Document Server

Traditional Genetic Algorithms (GAs) mating schemes select individuals for crossover independently of their genotypic or phenotypic similarities. In Nature, this behaviour is known as random mating. However, non-random schemes - in which individuals mate according to their kinship or likeness - are more common in natural systems. Previous studies indicate that, when applied to GAs, negative assortative mating (a specific type of non-random mating, also known as dissortative mating) may improve their performance (on both speed and reliability) in a wide range of problems. Dissortative mating maintains the genetic diversity at a higher level during the run, and that fact is frequently observed as an explanation for dissortative GAs ability to escape local optima traps. Dynamic problems, due to their specificities, demand special care when tuning a GA, because diversity plays an even more crucial role than it does when tackling static ones. This paper investigates the behaviour of dissortative mating GAs, namely...

Fernandes, C M; Rosa, A C

2009-01-01

378

Mating-type genes and sexual potential in the ascomycete genera Aspergillus and Penicillium  

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Mating-type and other ‘sex-related’ genes in the filamentous ascomcyete genera Aspergillus and Penicillium, were examined to investigate the potential sexual capacity of supposedly asexual species and also the possible evolutionary route and ancestry of mating strategy and mating-type genes. Two heterothallic and one homothallic sexual species were screened to determine the presence and genomic organisation of mating-type genes. An additional gene has previously been detected in Neosa...

Eagle, C.

2009-01-01