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Sample records for chordates evolutionary perspectives

  1. The synapsin gene family in basal chordates: evolutionary perspectives in metazoans

    OpenAIRE

    De Bernardi Fiorenza; Pennati Roberta; Moronti Luca; Candiani Simona; Benfenati Fabio; Pestarino Mario

    2010-01-01

    Abstract Background Synapsins are neuronal phosphoproteins involved in several functions correlated with both neurotransmitter release and synaptogenesis. The comprehension of the basal role of the synapsin family is hampered in vertebrates by the existence of multiple synapsin genes. Therefore, studying homologous genes in basal chordates, devoid of genome duplication, could help to achieve a better understanding of the complex functions of these proteins. Results In this study we report the...

  2. The synapsin gene family in basal chordates: evolutionary perspectives in metazoans

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    De Bernardi Fiorenza

    2010-01-01

    Full Text Available Abstract Background Synapsins are neuronal phosphoproteins involved in several functions correlated with both neurotransmitter release and synaptogenesis. The comprehension of the basal role of the synapsin family is hampered in vertebrates by the existence of multiple synapsin genes. Therefore, studying homologous genes in basal chordates, devoid of genome duplication, could help to achieve a better understanding of the complex functions of these proteins. Results In this study we report the cloning and characterization of the Ciona intestinalis and amphioxus Branchiostoma floridae synapsin transcripts and the definition of their gene structure using available C. intestinalis and B. floridae genomic sequences. We demonstrate the occurrence, in both model organisms, of a single member of the synapsin gene family. Full-length synapsin genes were identified in the recently sequenced genomes of phylogenetically diverse metazoans. Comparative genome analysis reveals extensive conservation of the SYN locus in several metazoans. Moreover, developmental expression studies underline that synapsin is a neuronal-specific marker in basal chordates and is expressed in several cell types of PNS and in many, if not all, CNS neurons. Conclusion Our study demonstrates that synapsin genes are metazoan genes present in a single copy per genome, except for vertebrates. Moreover, we hypothesize that, during the evolution of synapsin proteins, new domains are added at different stages probably to cope up with the increased complexity in the nervous system organization. Finally, we demonstrate that protochordate synapsin is restricted to the post-mitotic phase of CNS development and thereby is a good marker of postmitotic neurons.

  3. Evolutionary Patterns of RNA-Based Duplication in Non-Mammalian Chordates

    OpenAIRE

    Ming Chen; Ming Zou; Beide Fu; Xin Li; Vibranovski, Maria D.; Xiaoni Gan; Dengqiang Wang; Wen Wang; Manyuan Long; Shunping He

    2011-01-01

    The role of RNA-based duplication, or retroposition, in the evolution of new gene functions in mammals, plants, and Drosophila has been widely reported. However, little is known about RNA-based duplication in non-mammalian chordates. In this study, we screened ten non-mammalian chordate genomes for retrocopies and investigated their evolutionary patterns. We identified numerous retrocopies in these species. Examination of the age distribution of these retrocopies revealed no burst of young re...

  4. Evolutionary patterns of RNA-based duplication in non-mammalian chordates.

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    Ming Chen

    Full Text Available The role of RNA-based duplication, or retroposition, in the evolution of new gene functions in mammals, plants, and Drosophila has been widely reported. However, little is known about RNA-based duplication in non-mammalian chordates. In this study, we screened ten non-mammalian chordate genomes for retrocopies and investigated their evolutionary patterns. We identified numerous retrocopies in these species. Examination of the age distribution of these retrocopies revealed no burst of young retrocopies in ancient chordate species. Upon comparing these non-mammalian chordate species to the mammalian species, we observed that a larger fraction of the non-mammalian retrocopies was under strong evolutionary constraints than mammalian retrocopies are, as evidenced by signals of purifying selection and expression profiles. For the Western clawed frog, Medaka, and Sea squirt, many retrogenes have evolved gonad and brain expression patterns, similar to what was observed in human. Testing of retrogene movement in the Medaka genome, where the nascent sex chrosomes have been well assembled, did not reveal any significant gene movement. Taken together, our analyses demonstrate that RNA-based duplication generates many functional genes and can make a significant contribution to the evolution of non-mammalian genomes.

  5. Evolutionary history of chordate PAX genes: dynamics of change in a complex gene family.

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    Vanessa Rodrigues Paixão-Côrtes

    Full Text Available Paired box (PAX genes are transcription factors that play important roles in embryonic development. Although the PAX gene family occurs in animals only, it is widely distributed. Among the vertebrates, its 9 genes appear to be the product of complete duplication of an original set of 4 genes, followed by an additional partial duplication. Although some studies of PAX genes have been conducted, no comprehensive survey of these genes across the entire taxonomic unit has yet been attempted. In this study, we conducted a detailed comparison of PAX sequences from 188 chordates, which revealed restricted variation. The absence of PAX4 and PAX8 among some species of reptiles and birds was notable; however, all 9 genes were present in all 74 mammalian genomes investigated. A search for signatures of selection indicated that all genes are subject to purifying selection, with a possible constraint relaxation in PAX4, PAX7, and PAX8. This result indicates asymmetric evolution of PAX family genes, which can be associated with the emergence of adaptive novelties in the chordate evolutionary trajectory.

  6. Revaluation of deuterostome phylogeny and evolutionary relationships among chordate subphyla using mitogenome data.

    Science.gov (United States)

    Zhong, Jing; Zhang, Juyong; Mukwaya, Emmanuel; Wang, Yiquan

    2009-03-01

    The traditional knowledge in textbooks indicated that cephalochordates were the closest relatives to vertebrates among all extant organisms. However, this opinion was challenged by several recent phylogenetic studies using hundreds of nuclear genes. The researchers suggested that urochordates, but not cephalochordates, should be the closest living relatives to vertebrates. In the present study, by using data generated from hundreds of mtDNA sequences, we revalue the deuterostome phylogeny in terms of whole mitochondrial genomes (mitogenomes). Our results firmly demonstrate that each of extant deuterostome phyla and chordate subphyla is monophyletic. But the results present several alternative phylogenetic trees depending on different sequence datasets used in the analysis. Although no clear phylogenetic relationships are obtained, those trees indicate that the ancient common ancestor diversified rapidly soon after their appearance in the early Cambrian and generated all major deuterostome lineages during a short historical period, which is consistent with "Cambrian explosion" revealed by paleontologists. It was the 520-million-year's evolution that obscured the phylogenetic relationships of extant deuterostomes. Thus, we conclude that an integrative analysis approach rather than simply using more DNA sequences should be employed to address the distant evolutionary relationship. PMID:19302971

  7. Evolutionary origin of GnIH and NPFF in chordates: insights from novel amphioxus RFamide peptides.

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    Tomohiro Osugi

    Full Text Available Gonadotropin-inhibitory hormone (GnIH is a newly identified hypothalamic neuropeptide that inhibits pituitary hormone secretion in vertebrates. GnIH has an LPXRFamide (X = L or Q motif at the C-terminal in representative species of gnathostomes. On the other hand, neuropeptide FF (NPFF, a neuropeptide characterized as a pain-modulatory neuropeptide, in vertebrates has a PQRFamide motif similar to the C-terminal of GnIH, suggesting that GnIH and NPFF have diverged from a common ancestor. Because GnIH and NPFF belong to the RFamide peptide family in vertebrates, protochordate RFamide peptides may provide important insights into the evolutionary origin of GnIH and NPFF. In this study, we identified a novel gene encoding RFamide peptides and two genes of their putative receptors in the amphioxus Branchiostoma japonicum. Molecular phylogenetic analysis and synteny analysis indicated that these genes are closely related to the genes of GnIH and NPFF and their receptors of vertebrates. We further identified mature RFamide peptides and their receptors in protochordates. The identified amphioxus RFamide peptides inhibited forskolin induced cAMP signaling in the COS-7 cells with one of the identified amphioxus RFamide peptide receptors expressed. These results indicate that the identified protochordate RFamide peptide gene is a common ancestral form of GnIH and NPFF genes, suggesting that the origin of GnIH and NPFF may date back to the time of the emergence of early chordates. GnIH gene and NPFF gene may have diverged by whole-genome duplication in the course of vertebrate evolution.

  8. Evolutionary dynamics of olfactory receptor genes in chordates: interaction between environments and genomic contents

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    Niimura Yoshihito

    2009-12-01

    Full Text Available Abstract Olfaction is essential for the survival of animals. Versatile odour molecules in the environment are received by olfactory receptors (ORs, which form the largest multigene family in vertebrates. Identification of the entire repertories of OR genes using bioinformatics methods from the whole-genome sequences of diverse organisms revealed that the numbers of OR genes vary enormously, ranging from ~1,200 in rats and ~400 in humans to ~150 in zebrafish and ~15 in pufferfish. Most species have a considerable fraction of pseudogenes. Extensive phylogenetic analyses have suggested that the numbers of gene gains and losses are extremely large in the OR gene family, which is a striking example of the birth-and-death evolution. It appears that OR gene repertoires change dynamically, depending on each organism's living environment. For example, higher primates equipped with a well-developed vision system have lost a large number of OR genes. Moreover, two groups of OR genes for detecting airborne odorants greatly expanded after the time of terrestrial adaption in the tetrapod lineage, whereas fishes retain diverse repertoires of genes that were present in aquatic ancestral species. The origin of vertebrate OR genes can be traced back to the common ancestor of all chordate species, but insects, nematodes and echinoderms utilise distinctive families of chemoreceptors, suggesting that chemoreceptor genes have evolved many times independently in animal evolution.

  9. Evolutionary perspective in child growth.

    Science.gov (United States)

    Hochberg, Ze'ev

    2011-07-01

    Hereditary, environmental, and stochastic factors determine a child's growth in his unique environment, but their relative contribution to the phenotypic outcome and the extent of stochastic programming that is required to alter human phenotypes is not known because few data are available. This is an attempt to use evolutionary life-history theory in understanding child growth in a broad evolutionary perspective, using the data and theory of evolutionary predictive adaptive growth-related strategies. Transitions from one life-history phase to the next have inherent adaptive plasticity in their timing. Humans evolved to withstand energy crises by decreasing their body size, and evolutionary short-term adaptations to energy crises utilize a plasticity that modifies the timing of transition from infancy into childhood, culminating in short stature in times of energy crisis. Transition to juvenility is part of a strategy of conversion from a period of total dependence on the family and tribe for provision and security to self-supply, and a degree of adaptive plasticity is provided and determines body composition. Transition to adolescence entails plasticity in adapting to energy resources, other environmental cues, and the social needs of the maturing adolescent to determine life-span and the period of fecundity and fertility. Fundamental questions are raised by a life-history approach to the unique growth pattern of each child in his given genetic background and current environment.

  10. Evolutionary Perspective in Child Growth

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    Ze’ev Hochberg

    2011-07-01

    Full Text Available Hereditary, environmental, and stochastic factors determine a child’s growth in his unique environment, but their relative contribution to the phenotypic outcome and the extent of stochastic programming that is required to alter human phenotypes is not known because few data are available. This is an attempt to use evolutionary life-history theory in understanding child growth in a broad evolutionary perspective, using the data and theory of evolutionary predictive adaptive growth-related strategies. Transitions from one life-history phase to the next have inherent adaptive plasticity in their timing. Humans evolved to withstand energy crises by decreasing their body size, and evolutionary short-term adaptations to energy crises utilize a plasticity that modifies the timing of transition from infancy into childhood, culminating in short stature in times of energy crisis. Transition to juvenility is part of a strategy of conversion from a period of total dependence on the family and tribe for provision and security to self-supply, and a degree of adaptive plasticity is provided and determines body composition. Transition to adolescence entails plasticity in adapting to energy resources, other environmental cues, and the social needs of the maturing adolescent to determine life-span and the period of fecundity and fertility. Fundamental questions are raised by a life-history approach to the unique growth pattern of each child in his given genetic background and current environment.

  11. Hemichordates and the origin of chordates

    Science.gov (United States)

    Gerhart, John; Lowe, Christopher; Kirschner, Marc

    2005-01-01

    Hemichordates, the phylum of bilateral animals most closely related to chordates, could reveal the evolutionary origins of chordate traits such as the nerve cord, notochord, gill slits and tail. The anteroposterior maps of gene expression domains for 38 genes of chordate neural patterning are highly similar for hemichordates and chordates, even though hemichordates have a diffuse nerve-net. About 40% of the domains are not present in protostome maps. We propose that this map, the gill slits and the tail date to the deuterostome ancestor. The map of dorsoventral expression domains, centered on a Bmp-Chordin axis, differs between the two groups; hemichordates resemble protostomes more than they do chordates. The dorsoventral axis might have undergone extensive modification in the chordate line, including centralization of the nervous system, segregation of epidermis, derivation of the notochord, and an inversion of organization.

  12. Evolutionary conservation of the presumptive neural plate markers AmphiSox1/2/3 and AmphiNeurogenin in the invertebrate chordate amphioxus

    Science.gov (United States)

    Holland, L. Z.; Schubert, M.; Holland, N. D.; Neuman, T.

    2000-01-01

    Amphioxus, as the closest living invertebrate relative of the vertebrates, can give insights into the evolutionary origin of the vertebrate body plan. Therefore, to investigate the evolution of genetic mechanisms for establishing and patterning the neuroectoderm, we cloned and determined the embryonic expression of two amphioxus transcription factors, AmphiSox1/2/3 and AmphiNeurogenin. These genes are the earliest known markers for presumptive neuroectoderm in amphioxus. By the early neurula stage, AmphiNeurogenin expression becomes restricted to two bilateral columns of segmentally arranged neural plate cells, which probably include precursors of motor neurons. This is the earliest indication of segmentation in the amphioxus nerve cord. Later, expression extends to dorsal cells in the nerve cord, which may include precursors of sensory neurons. By the midneurula, AmphiSox1/2/3 expression becomes limited to the dorsal part of the forming neural tube. These patterns resemble those of their vertebrate and Drosophila homologs. Taken together with the evolutionarily conserved expression of the dorsoventral patterning genes, BMP2/4 and chordin, in nonneural and neural ectoderm, respectively, of chordates and Drosophila, our results are consistent with the evolution of the chordate dorsal nerve cord and the insect ventral nerve cord from a longitudinal nerve cord in a common bilaterian ancestor. However, AmphiSox1/2/3 differs from its vertebrate homologs in not being expressed outside the CNS, suggesting that additional roles for this gene have evolved in connection with gene duplication in the vertebrate lineage. In contrast, expression in the midgut of AmphiNeurogenin together with the gene encoding the insulin-like peptide suggests that amphioxus may have homologs of vertebrate pancreatic islet cells, which express neurogenin3. In addition, AmphiNeurogenin, like its vertebrate and Drosophila homologs, is expressed in apparent precursors of epidermal chemosensory and

  13. Why are neurotransmitters neurotoxic? An evolutionary perspective

    OpenAIRE

    Keith D. Harris; Meital Weiss; Amotz Zahavi

    2014-01-01

    In the CNS, minor changes in the concentration of neurotransmitters such as glutamate or dopamine can lead to neurodegenerative diseases. We present an evolutionary perspective on the function of neurotransmitter toxicity in the CNS. We hypothesize that neurotransmitters are selected because of their toxicity, which serves as a test of neuron quality and facilitates the selection of neuronal pathways. This perspective may offer additional explanations for the reduction of neurotransmitter con...

  14. Phylostratigraphic profiles in zebrafish uncover chordate origins of the vertebrate brain.

    Science.gov (United States)

    Šestak, Martin Sebastijan; Domazet-Lošo, Tomislav

    2015-02-01

    An elaborated tripartite brain is considered one of the important innovations of vertebrates. Other extant chordate groups have a more basic brain organization. For instance, cephalochordates possess a relatively simple brain possibly homologous to the vertebrate forebrain and hindbrain, whereas tunicates display the tripartite organization, but without the specialized brain centers. The difference in anatomical complexity is even more pronounced if one compares chordates with other deuterostomes that have only a diffuse nerve net or alternatively a rather simple central nervous system. To gain a new perspective on the evolutionary roots of the complex vertebrate brain, we made here a phylostratigraphic analysis of gene expression patterns in the developing zebrafish (Danio rerio). The recovered adaptive landscape revealed three important periods in the evolutionary history of the zebrafish brain. The oldest period corresponds to preadaptive events in the first metazoans and the emergence of the nervous system at the metazoan-eumetazoan transition. The origin of chordates marks the next phase, where we found the overall strongest adaptive imprint in almost all analyzed brain regions. This finding supports the idea that the vertebrate brain evolved independently of the brains within the protostome lineage. Finally, at the origin of vertebrates we detected a pronounced signal coming from the dorsal telencephalon, in agreement with classical theories that consider this part of the cerebrum a genuine vertebrate innovation. Taken together, these results reveal a stepwise adaptive history of the vertebrate brain where most of its extant organization was already present in the chordate ancestor. PMID:25415965

  15. Indoor Thermal Comfort, an Evolutionary Biology Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Stoops, John L.

    2006-04-15

    As is becoming increasingly clear, the human species evolvedin the East African savannah. Details of the precise evolutionary chainremain unresolved however it appears that the process lasted severalmillion years, culminating with the emergence of modern Homo sapiensroughly 200,000 years ago. Following that final evolutionary developmentmodern Homo sapiens relatively quickly populated the entire world.Clearly modern Homo sapiens is a successful, resourceful and adaptablespecies. In the developed societies, modern humans live an existence farremoved from our evolutionary ancestors. As we have learned over the lastcentury, this "new" lifestyle can often result in unintendedconsequences. Clearly, our modern access to food, shelter, transportationand healthcare has resulted in greatly expanded expected lifespan butthis new lifestyle can also result in the emergence of different kinds ofdiseases and health problems. The environment in modern buildings haslittle resemblance to the environment of the savannah. We strive tocreate environments with little temperature, air movement and lightvariation. Building occupants often express great dissatisfaction withthese modern created environments and a significant fraction even developsomething akin to allergies to specific buildings (sick buildingsyndrome). Are the indoor environments we are creating fundamentallyunhealthy -- when examined from an evolutionary perspective?

  16. Evolutionary perspectives into placental biology and disease

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    Edward B. Chuong

    2013-12-01

    Full Text Available In all mammals including humans, development takes place within the protective environment of the maternal womb. Throughout gestation, nutrients and waste products are continuously exchanged between mother and fetus through the placenta. Despite the clear importance of the placenta to successful pregnancy and the health of both mother and offspring, relatively little is understood about the biology of the placenta and its role in pregnancy-related diseases. Given that pre- and peri-natal diseases involving the placenta affect millions of women and their newborns worldwide, there is an urgent need to understand placenta biology and development. Here, we suggest that the placenta is an organ under unique selective pressures that have driven its rapid diversification throughout mammalian evolution. The high divergence of the placenta complicates the use of non-human animal models and necessitates an evolutionary perspective when studying its biology and role in disease. We suggest that diversifying evolution of the placenta is primarily driven by intraspecies evolutionary conflict between mother and fetus, and that many pregnancy diseases are a consequence of this evolutionary force. Understanding how maternal–fetal conflict shapes both basic placental and reproductive biology – in all species – will provide key insights into diseases of pregnancy.

  17. Evolutionary perspectives on human height variation.

    Science.gov (United States)

    Stulp, Gert; Barrett, Louise

    2016-02-01

    Human height is a highly variable trait, both within and between populations, has a high heritability, and influences the manner in which people behave and are treated in society. Although we know much about human height, this information has rarely been brought together in a comprehensive, systematic fashion. Here, we present a synthetic review of the literature on human height from an explicit evolutionary perspective, addressing its phylogenetic history, development, and environmental and genetic influences on growth and stature. In addition to presenting evidence to suggest the past action of natural selection on human height, we also assess the evidence that natural and sexual selection continues to act on height in contemporary populations. Although there is clear evidence to suggest that selection acts on height, mainly through life-history processes but perhaps also directly, it is also apparent that methodological factors reduce the confidence with which such inferences can be drawn, and there remain surprising gaps in our knowledge. The inability to draw firm conclusions about the adaptiveness of such a highly visible and easily measured trait suggests we should show an appropriate degree of caution when dealing with other human traits in evolutionary perspective. PMID:25530478

  18. Unique Development in Hemichordates Suggest Some Unique Features of Chordates

    OpenAIRE

    Lowe, Christopher J.; Mark Terasaki; Michael Wu; Freeman, Robert M.; Linda Runft; Kristen Kwan; Saori Haigo; Jochanan Aronowicz; Eric Lander; Chris Gruber; Mark Smith; Marc Kirschner; John Gerhart

    2006-01-01

    We have compared the dorsoventral development of hemichordates and chordates to deduce the organization of their common ancestor, and hence to identify the evolutionary modifications of the chordate body axis after the lineages split. In the hemichordate embryo, genes encoding bone morphogenetic proteins (Bmp) 2/4 and 5/8, as well as several genes for modulators of Bmp activity, are expressed in a thin stripe of ectoderm on one midline, historically called "dorsal." On the opposite midline, t...

  19. An Evolutionary Perspective on the Crabtree Effect

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    Thomas ePfeiffer

    2014-10-01

    Full Text Available The capability to ferment sugars into ethanol is a key metabolic trait of yeasts. Crabtree-positive yeasts use fermentation even in the presence of oxygen, where they could, in principle, rely on the respiration pathway. This is surprising because fermentation has a much lower ATP yield than respiration (2 ATP vs. approximately 18 ATP per glucose. While genetic events in the evolution of the Crabtree effect have been identified, the selective advantages provided by this trait remain controversial. In this review we analyse explanations for the emergence of the Crabtree effect from an evolutionary and game-theoretical perspective. We argue that an increased rate of ATP production is likely the most important factor behind the emergence of the Crabtree effect.

  20. Human growth: evolutionary and life history perspectives.

    Science.gov (United States)

    Gluckman, Peter D; Beedle, Alan S; Hanson, Mark A; Low, Felicia M

    2013-01-01

    Evolutionary and life history perspectives allow a fuller understanding of both patterns of growth and development and variations in disease risk. Evolutionary processes act to ensure successful reproduction and not the preservation of health and longevity, and this entails trade-offs both between traits and across the life course. Developmental plasticity adjusts the developmental trajectory so that the phenotype in childhood and through peak reproduction will suit predicted environmental conditions - a capacity that may become maladaptive should early-life predictions be inaccurate. Bipedalism and consequent pelvic narrowing in humans have led to the evolution of secondary altricialism. Shorter inter-birth intervals enabled by appropriate social support structures have allowed increased fecundity/fitness. The age at puberty has fallen over the past two centuries, perhaps resulting from changes in maternal and infant health and nutrition. The timing of puberty is also advanced by conditions of high extrinsic mortality in hunter-gatherers and is reflected in developed countries where a poor or disadvantaged start to life may also accelerate maturation. The postpubertal individual is physically and psychosexually mature, but neural executive function only reaches full maturity in the third decade of life; this mismatch may account for increased adolescent morbidity and mortality in those with earlier pubertal onset. PMID:23502143

  1. Evolutionary Perspective on Collective Decision Making

    Science.gov (United States)

    Farrell, Dene; Sayama, Hiroki; Dionne, Shelley D.; Yammarino, Francis J.; Wilson, David Sloan

    Team decision making dynamics are investigated from a novel perspective by shifting agency from decision makers to representations of potential solutions. We provide a new way to navigate social dynamics of collective decision making by interpreting decision makers as constituents of an evolutionary environment of an ecology of evolving solutions. We demonstrate distinct patterns of evolution with respect to three forms of variation: (1) Results with random variations in utility functions of individuals indicate that groups demonstrating minimal internal variation produce higher true utility values of group solutions and display better convergence; (2) analysis of variations in behavioral patterns within a group shows that a proper balance between selective and creative evolutionary forces is crucial to producing adaptive solutions; and (3) biased variations of the utility functions diminish the range of variation for potential solution utility, leaving only the differential of convergence performance static. We generally find that group cohesion (low random variation within a group) and composition (appropriate variation of behavioral patterns within a group) are necessary for a successful navigation of the solution space, but performance in both cases is susceptible to group level biases.

  2. rRNA genes from the lower chordate Herdmania momus: structural similarity with higher eukaryotes.

    OpenAIRE

    Degnan, B M; Yan, J.; Hawkins, C J; Lavin, M F

    1990-01-01

    Ascidians, primitive chordates that have retained features of the likely progenitors to all vertebrates, are a useful model to study the evolutionary relationship of chordates to other animals. We have selected the well characterized ribosomal RNA (rRNA) genes to investigate this relationship, and we describe here the cloning and characterization of an entire ribosomal DNA (rDNA) tandem repeat unit from a lower chordate, the ascidian Herdmania momus. rDNA copy number and considerable sequence...

  3. The Middle Cambrian fossil Pikaia and the evolution of chordate swimming

    OpenAIRE

    Lacalli Thurston

    2012-01-01

    Abstract Conway Morris and Caron (2012) have recently published an account of virtually all the available information on Pikaia gracilens, a well-known Cambrian fossil and supposed basal chordate, and propose on this basis some new ideas about Pikaia’s anatomy and evolutionary significance. Chief among its chordate-like features are the putative myomeres, a regular series of vertical bands that extends the length of the body. These differ from the myomeres of living chordates in that boundari...

  4. Tunicate mitogenomics and phylogenetics: peculiarities of the Herdmania momus mitochondrial genome and support for the new chordate phylogeny.

    OpenAIRE

    Loya Yossi; Shenkar Noa; Blanquart Samuel; Delsuc Frédéric; Tsagkogeorga Georgia; Singh Tiratha; Douzery Emmanuel JP; Huchon Dorothée

    2009-01-01

    Abstract Background Tunicates represent a key metazoan group as the sister-group of vertebrates within chordates. The six complete mitochondrial genomes available so far for tunicates have revealed distinctive features. Extensive gene rearrangements and particularly high evolutionary rates have been evidenced with regard to other chordates. This peculiar evolutionary dynamics has hampered the reconstruction of tunicate phylogenetic relationships within chordates based on mitogenomic data. Res...

  5. Temporal knowledge and autobiographical memory: an evolutionary perspective

    OpenAIRE

    Skowronski, John J.; Sedikides, Constantine

    2007-01-01

    Section I: Philosophical issues 1. Evolutionary pyschology in the round , Robin Dunbar & Louise Barrett 2. The power of culture , Henry Plotkin 3. Evolution and psychology in philosophical perspective , Matteo Mameli 4. Niche construction, human behavioural ecology and evolutionary psychology , Kevin N Laland 5. Group level evolutionary processes , David Sloan Wilson Section II: The comparative Approach 6. Homologizing the mind , Drew Rendall, Hugh Nottman & John R Vokey ...

  6. Regional systems of innovation: an evolutionary perspective

    OpenAIRE

    Cooke, P.; M G Uranga; G Etxebarria

    1998-01-01

    The authors develop the concept of regional systems of innovation and relate it to preexisting research on national systems of innovation. They argue that work conducted in the 'new regional science' field is complementary to systems of innovation approaches. They seek to link new regional work to evolutionary economics, and argue for the development of evolutionary regional science. Common elements of interest to evolutionary innovation research and new regional science are important in unde...

  7. Developmental genetics in primitive chordates.

    OpenAIRE

    P. SORDINO; L. Belluzzi; De Santis, R; Smith, W.C.

    2001-01-01

    Recent advances in the study of the genetics and genomics of urochordates testify to a renewed interest in this chordate subphylum, believed to be the most primitive extant chordate relatives of the vertebrates. In addition to their primitive nature, many features of their reproduction and early development make the urochordates ideal model chordates for developmental genetics. Many urochordates spawn large numbers of transparent and externally developing embryos on a daily basis. Additionall...

  8. The Carbon Crisis: An Evolutionary Perspective

    Science.gov (United States)

    Peacock, K.

    2013-12-01

    By the 'carbon crisis' I mean the coupled crises of the depletion of the highest-EROI sources of fossil fuels and the global warming caused by our use of those fossil fuels. (EROI means 'energy return on energy investment'; Hall 2011.) While global warming is arguably more urgent, either of these factors would sooner or later be sufficient by itself to call a halt to our global-scale, energy-intensive, high technology economy. In lethal combination, they threaten to drastically reduce the capacity of the planet to support 7+ billion talking hominids. I will pull the camera back for a very long view and characterize the carbon crisis and our possible responses to it from an evolutionary and ecological perspective. It remains unclear why sapiens emerged rather suddenly as the most successful member of the family Homo about 50 to 60 kya; some argue that this neurological explosion could be due to our ancestors having survived the rigors of the Toba population bottleneck, which presumably would have favoured high adaptability (Ambrose 1998). Whatever the cause, Paleolithic humans deployed an unprecedented combination of technological and social ingenuity (the capacity for adaptive social organization; Homer-Dixon 2001). Aided by the relatively benign climate of the Holocene and ultimately by our increasing ability to tap into the resources of the 'found' ecology, especially the vast stores of hydrocarbons bequeathed by the Paleozoic and Mesozoic eras, our population has grown exponentially to its present unsteady pinnacle of (possibly) temporary reproductive success. The question now is what happens next. It was human ingenuity that got us through the ice age, put footprints on the Moon, and brought us to this crisis point; now, only human ingenuity (both social and technical) can get us past it. Our species will finally achieve a sustainable mode of existence on this planet when (in E. Odum's words; 1973) 'the present-day concept of ';unlimited exploitation of

  9. Retinoic acid signaling and the evolution of chordates

    Directory of Open Access Journals (Sweden)

    2006-04-01

    Full Text Available In chordates, which comprise urochordates, cephalochordates and vertebrates, the vitamin A-derived morphogen retinoic acid (RA has a pivotal role during development. Altering levels of endogenous RA signaling during early embryology leads to severe malformations, mainly due to incorrect positional codes specifying the embryonic anteroposterior body axis. In this review, we present our current understanding of the RA signaling pathway and its roles during chordate development. In particular, we focus on the conserved roles of RA and its downstream mediators, the Hox genes, in conveying positional patterning information to different embryonic tissues, such as the endoderm and the central nervous system. We find that some of the control mechanisms governing RA-mediated patterning are well conserved between vertebrates and invertebrate chordates, such as the cephalochordate amphioxus. In contrast, outside the chordates, evidence for roles of RA signaling is scarce and the evolutionary origin of the RA pathway itself thus remains elusive. In sum, to fully understand the evolutionary history of the RA pathway, future research should focus on identification and study of components of the RA signaling cascade in non-chordate deuterostomes (such as hemichordates and echinoderms and other invertebrates, such as insects, mollusks and cnidarians.

  10. (Flat)fish stocks in an ecosystem and evolutionary perspective

    OpenAIRE

    Volckaert, Filip

    2013-01-01

    The delineation of natural populations has many faces. While a stock relates to a management unit of organisms, the biological concept of a population may relate to a demographic/ecological perspective on interacting organisms or an evolving group of organisms. In addition, it has become increasingly clear that the time and spatial scales of the ecological and evolutionary population have much in common. Evolutionary population models, which are the focus of this paper, harbor independent inf...

  11. An Evolutionary Perspective on War Heroism

    NARCIS (Netherlands)

    Rusch, Hannes; Störmer, C.

    2015-01-01

    Humans are one of the most cooperative and altruistic species on the planet. At the same time, humans have a long history of violent and deadly intergroup conflicts or wars. Recently, contemporary evolutionary theorists have revived Charles Darwin’s idea that human in-group altruism and out-group ho

  12. The evolutionary differentiation of two histone H2A.Z variants in chordates (H2A.Z-1 and H2A.Z-2 is mediated by a stepwise mutation process that affects three amino acid residues

    Directory of Open Access Journals (Sweden)

    Ausió Juan

    2009-02-01

    Full Text Available Abstract Background The histone H2A family encompasses the greatest number of core histone variants of which the replacement variant H2A.Z is currently one of the most heavily studied. No clear mechanism for the functional variability that H2A.Z imparts to chromatin has yet been proposed. While most of the past studies have referred to H2A.Z generically as a single protein, in vertebrates it is a mixture of two protein forms H2A.Z-1 (previously H2A.Z and H2A.Z-2 (previously H2A.F/Z or H2A.V that differ by three amino acids. Results We have performed an extensive study on the long-term evolution of H2A.Z across metazoans with special emphasis on the possible selective mechanisms responsible for the differentiation between H2A.Z-1 and H2A.Z-2. Our results reveal a common origin of both forms early in chordate evolution. The evolutionary process responsible for the differentiation involves refined stepwise mutation change within the codons of the three differential residues. This eventually led to differences in the intensity of the selective constraints acting upon the different H2A.Z forms in vertebrates. Conclusion The results presented in this work definitively reveal that the existence of H2A.Z-1 and H2A.Z-2 is not a whim of random genetic drift. Our analyses demonstrate that H2A.Z-2 is not only subject to a strong purifying selection but it is significantly more evolutionarily constrained than H2A.Z-1. Whether or not the evolutionary drift between H2A.Z-1 and H2A.Z-2 has resulted in a functional diversification of these proteins awaits further research. Nevertheless, the present work suggests that in the process of their differently constrained evolutionary pathways, these two forms may have acquired new or complementary functions.

  13. A Study of Learning Strategic Alliances from an Evolutionary Perspective

    Institute of Scientific and Technical Information of China (English)

    CAO Yong-hui

    2008-01-01

    We present an exploratory framework based on an amalgamation of organizational learning and strategic alliance literatures. It highlights the importance of understanding learning in alliance partnerships from an evolutionary perspective. The research proposes that as alliances progress from awareness through commitment phases, learning priorities change.

  14. Attachment in Middle Childhood: An Evolutionary-Developmental Perspective

    Science.gov (United States)

    Del Giudice, Marco

    2015-01-01

    Middle childhood is a key transitional stage in the development of attachment processes and representations. Here I discuss the middle childhood transition from an evolutionary-developmental perspective and show how this approach offers fresh insight into the function and organization of attachment in this life stage. I begin by presenting an…

  15. An Evolutionary Perspective on Parental and Grandparental Investment

    NARCIS (Netherlands)

    Heijkoop, M.

    2010-01-01

    Although great effort has been spent on studying the effects of parenting on child development, much less research has focused on factors that predict individual differences in parental investment. In this dissertation, an evolutionary psychological perspective was used to identify characteristics i

  16. Human Phenotypic Diversity: An Evolutionary Perspective.

    Science.gov (United States)

    Balaresque, P; King, T E

    2016-01-01

    As humans migrated across the world, they encountered new environments requiring them to adapt to new challenges that presented themselves. The distribution of human phenotypes observed today is the result of this continuous adaptation, via biological/physiological and cultural means, and also by the modification of cultural practices, which leads to biological changes. In this chapter, we examine a number of adaptive traits and the roles played by their genetic and environmental determinants. We have selected a few traits used for human identification purposes (externally visible characteristics), associated with human metabolism and linked to a shift in subsistence method and food consumption. We discuss the evolutionary processes that have affected the temporal and spatial distribution of these traits, including natural, sexual, and cultural selection. PMID:27282030

  17. Dorsoventral patterning in hemichordates: insights into early chordate evolution.

    Directory of Open Access Journals (Sweden)

    Christopher J Lowe

    2006-09-01

    Full Text Available We have compared the dorsoventral development of hemichordates and chordates to deduce the organization of their common ancestor, and hence to identify the evolutionary modifications of the chordate body axis after the lineages split. In the hemichordate embryo, genes encoding bone morphogenetic proteins (Bmp 2/4 and 5/8, as well as several genes for modulators of Bmp activity, are expressed in a thin stripe of ectoderm on one midline, historically called "dorsal." On the opposite midline, the genes encoding Chordin and Anti-dorsalizing morphogenetic protein (Admp are expressed. Thus, we find a Bmp-Chordin developmental axis preceding and underlying the anatomical dorsoventral axis of hemichordates, adding to the evidence from Drosophila and chordates that this axis may be at least as ancient as the first bilateral animals. Numerous genes encoding transcription factors and signaling ligands are expressed in the three germ layers of hemichordate embryos in distinct dorsoventral domains, such as pox neuro, pituitary homeobox, distalless, and tbx2/3 on the Bmp side and netrin, mnx, mox, and single-minded on the Chordin-Admp side. When we expose the embryo to excess Bmp protein, or when we deplete endogenous Bmp by small interfering RNA injections, these expression domains expand or contract, reflecting their activation or repression by Bmp, and the embryos develop as dorsalized or ventralized limit forms. Dorsoventral patterning is independent of anterior/posterior patterning, as in Drosophila but not chordates. Unlike both chordates and Drosophila, neural gene expression in hemichordates is not repressed by high Bmp levels, consistent with their development of a diffuse rather than centralized nervous system. We suggest that the common ancestor of hemichordates and chordates did not use its Bmp-Chordin axis to segregate epidermal and neural ectoderm but to pattern many other dorsoventral aspects of the germ layers, including neural cell fates

  18. How much does the amphioxus genome represent the ancestor of chordates?

    OpenAIRE

    Louis A.; Roest Crollius H.; Robinson-Rechavi M.

    2012-01-01

    One of the main motivations to study amphioxus is its potential for understanding the last common ancestor of chordates, which notably gave rise to the vertebrates. An important feature in this respect is the slow evolutionary rate that seems to have characterized the cephalochordate lineage, making amphioxus an interesting proxy for the chordate ancestor, as well as a key lineage to include in comparative studies. Whereas slow evolution was first noticed at the phenotypic level, it has also ...

  19. Neurohormetic phytochemicals: An evolutionary-bioenergetic perspective.

    Science.gov (United States)

    Murugaiyah, Vikneswaran; Mattson, Mark P

    2015-10-01

    The impact of dietary factors on brain health and vulnerability to disease is increasingly appreciated. The results of epidemiological studies, and intervention trials in animal models suggest that diets rich in phytochemicals can enhance neuroplasticity and resistance to neurodegeneration. Here we describe how interactions of plants and animals during their co-evolution, and resulting reciprocal adaptations, have shaped the remarkable characteristics of phytochemicals and their effects on the physiology of animal cells in general, and neurons in particular. Survival advantages were conferred upon plants capable of producing noxious bitter-tasting chemicals, and on animals able to tolerate the phytochemicals and consume the plants as an energy source. The remarkably diverse array of phytochemicals present in modern fruits, vegetables spices, tea and coffee may have arisen, in part, from the acquisition of adaptive cellular stress responses and detoxification enzymes in animals that enabled them to consume plants containing potentially toxic chemicals. Interestingly, some of the same adaptive stress response mechanisms that protect neurons against noxious phytochemicals are also activated by dietary energy restriction and vigorous physical exertion, two environmental challenges that shaped brain evolution. In this perspective article, we describe some of the signaling pathways relevant to cellular energy metabolism that are modulated by 'neurohormetic phytochemicals' (potentially toxic chemicals produced by plants that have beneficial effects on animals when consumed in moderate amounts). We highlight the cellular bioenergetics-related sirtuin, adenosine monophosphate activated protein kinase (AMPK), mammalian target of rapamycin (mTOR) and insulin-like growth factor 1 (IGF-1) pathways. The inclusion of dietary neurohormetic phytochemicals in an overall program for brain health that also includes exercise and energy restriction may find applications in the

  20. Evidence Combination From an Evolutionary Game Theory Perspective.

    Science.gov (United States)

    Deng, Xinyang; Han, Deqiang; Dezert, Jean; Deng, Yong; Shyr, Yu

    2016-09-01

    Dempster-Shafer evidence theory is a primary methodology for multisource information fusion because it is good at dealing with uncertain information. This theory provides a Dempster's rule of combination to synthesize multiple evidences from various information sources. However, in some cases, counter-intuitive results may be obtained based on that combination rule. Numerous new or improved methods have been proposed to suppress these counter-intuitive results based on perspectives, such as minimizing the information loss or deviation. Inspired by evolutionary game theory, this paper considers a biological and evolutionary perspective to study the combination of evidences. An evolutionary combination rule (ECR) is proposed to help find the most biologically supported proposition in a multievidence system. Within the proposed ECR, we develop a Jaccard matrix game to formalize the interaction between propositions in evidences, and utilize the replicator dynamics to mimick the evolution of propositions. Experimental results show that the proposed ECR can effectively suppress the counter-intuitive behaviors appeared in typical paradoxes of evidence theory, compared with many existing methods. Properties of the ECR, such as solution's stability and convergence, have been mathematically proved as well.

  1. Evidence Combination From an Evolutionary Game Theory Perspective.

    Science.gov (United States)

    Deng, Xinyang; Han, Deqiang; Dezert, Jean; Deng, Yong; Shyr, Yu

    2016-09-01

    Dempster-Shafer evidence theory is a primary methodology for multisource information fusion because it is good at dealing with uncertain information. This theory provides a Dempster's rule of combination to synthesize multiple evidences from various information sources. However, in some cases, counter-intuitive results may be obtained based on that combination rule. Numerous new or improved methods have been proposed to suppress these counter-intuitive results based on perspectives, such as minimizing the information loss or deviation. Inspired by evolutionary game theory, this paper considers a biological and evolutionary perspective to study the combination of evidences. An evolutionary combination rule (ECR) is proposed to help find the most biologically supported proposition in a multievidence system. Within the proposed ECR, we develop a Jaccard matrix game to formalize the interaction between propositions in evidences, and utilize the replicator dynamics to mimick the evolution of propositions. Experimental results show that the proposed ECR can effectively suppress the counter-intuitive behaviors appeared in typical paradoxes of evidence theory, compared with many existing methods. Properties of the ECR, such as solution's stability and convergence, have been mathematically proved as well. PMID:26285231

  2. The Exercise–Affect–Adherence Pathway: An Evolutionary Perspective

    Science.gov (United States)

    Lee, Harold H.; Emerson, Jessica A.; Williams, David M.

    2016-01-01

    The low rates of regular exercise and overall physical activity (PA) in the general population represent a significant public health challenge. Previous research suggests that, for many people, exercise leads to a negative affective response and, in turn, reduced likelihood of future exercise. The purpose of this paper is to examine this exercise–affect–adherence relationship from an evolutionary perspective. Specifically, we argue that low rates of physical exercise in the general population are a function of the evolved human tendency to avoid unnecessary physical exertion. This innate tendency evolved because it allowed our evolutionary ancestors to conserve energy for physical activities that had immediate adaptive utility such as pursuing prey, escaping predators, and engaging in social and reproductive behaviors. The commonly observed negative affective response to exercise is an evolved proximate psychological mechanism through which humans avoid unnecessary energy expenditure. The fact that the human tendencies toward negative affective response to and avoidance of unnecessary physical activities are innate does not mean that they are unchangeable. Indeed, it is only because of human-engineered changes in our environmental conditions (i.e., it is no longer necessary for us to work for our food) that our predisposition to avoid unnecessary physical exertion has become a liability. Thus, it is well within our capabilities to reengineer our environments to once again make PA necessary or, at least, to serve an immediate functional purpose. We propose a two-pronged approach to PA promotion based on this evolutionary functional perspective: first, to promote exercise and other physical activities that are perceived to have an immediate purpose, and second, to instill greater perceived purpose for a wider range of physical activities. We posit that these strategies are more likely to result in more positive (or less negative) affective responses to exercise

  3. Seeing chordate evolution through the Ciona genome sequence

    OpenAIRE

    Cañestro, Cristian; Bassham, Susan; Postlethwait, John H.

    2003-01-01

    A draft sequence of the compact genome of the sea squirt Ciona intestinalis, a non-vertebrate chordate that diverged very early from other chordates, including vertebrates, illuminates how chordates originated and how vertebrate developmental innovations evolved.

  4. An evolutionary perspective on epistasis and the missing heritability.

    Directory of Open Access Journals (Sweden)

    Gibran Hemani

    2013-02-01

    Full Text Available The relative importance between additive and non-additive genetic variance has been widely argued in quantitative genetics. By approaching this question from an evolutionary perspective we show that, while additive variance can be maintained under selection at a low level for some patterns of epistasis, the majority of the genetic variance that will persist is actually non-additive. We propose that one reason that the problem of the "missing heritability" arises is because the additive genetic variation that is estimated to be contributing to the variance of a trait will most likely be an artefact of the non-additive variance that can be maintained over evolutionary time. In addition, it can be shown that even a small reduction in linkage disequilibrium between causal variants and observed SNPs rapidly erodes estimates of epistatic variance, leading to an inflation in the perceived importance of additive effects. We demonstrate that the perception of independent additive effects comprising the majority of the genetic architecture of complex traits is biased upwards and that the search for causal variants in complex traits under selection is potentially underpowered by parameterising for additive effects alone. Given dense SNP panels the detection of causal variants through genome-wide association studies may be improved by searching for epistatic effects explicitly.

  5. Molecular evolution of a chordate specific family of G protein-coupled receptors

    Directory of Open Access Journals (Sweden)

    Leese Florian

    2011-08-01

    Full Text Available Abstract Background Chordate evolution is a history of innovations that is marked by physical and behavioral specializations, which led to the development of a variety of forms from a single ancestral group. Among other important characteristics, vertebrates obtained a well developed brain, anterior sensory structures, a closed circulatory system and gills or lungs as blood oxygenation systems. The duplication of pre-existing genes had profound evolutionary implications for the developmental complexity in vertebrates, since mutations modifying the function of a duplicated protein can lead to novel functions, improving the evolutionary success. Results We analyzed here the evolution of the GPRC5 family of G protein-coupled receptors by comprehensive similarity searches and found that the receptors are only present in chordates and that the size of the receptor family expanded, likely due to genome duplication events in the early history of vertebrate evolution. We propose that a single GPRC5 receptor coding gene originated in a stem chordate ancestor and gave rise by duplication events to a gene family comprising three receptor types (GPRC5A-C in vertebrates, and a fourth homologue present only in mammals (GPRC5D. Additional duplications of GPRC5B and GPRC5C sequences occurred in teleost fishes. The finding that the expression patterns of the receptors are evolutionarily conserved indicates an important biological function of these receptors. Moreover, we found that expression of GPRC5B is regulated by vitamin A in vivo, confirming previous findings that linked receptor expression to retinoic acid levels in tumor cell lines and strengthening the link between the receptor expression and the development of a complex nervous system in chordates, known to be dependent on retinoic acid signaling. Conclusions GPRC5 receptors, a class of G protein-coupled receptors with unique sequence characteristics, may represent a molecular novelty that helped non-chordates

  6. The Evolution of Dopamine Systems in Chordates

    OpenAIRE

    Philippe Vernier

    2011-01-01

    Dopamine (DA) neurotransmission in the central nervous system (CNS) is found throughout chordates, and its emergence predates the divergence of chordates. Many of the molecular components of DA systems, such as biosynthetic enzymes, transporters, and receptors, are shared with those of other monoamine systems, suggesting the common origin of these systems. In the mammalian CNS, the DA neurotransmitter systems are diversified and serve for visual and olfactory perception, sensory–motor program...

  7. Sex in an Evolutionary Perspective: Just Another Reaction Norm

    OpenAIRE

    Ah-King, Malin; Nylin, Sören

    2010-01-01

    It is common to refer to all sorts of clear-cut differences between the sexes as something that is biologically almost inevitable. Although this does not reflect the status of evolutionary theory on sex determination and sexual dimorphism, it is probably a common view among evolutionary biologists as well, because of the impact of sexual selection theory. To get away from thinking about biological sex and traits associated with a particular sex as something static, it should be recognized tha...

  8. Behavioral genetics and evolutionary psychology: unified perspective on personality research.

    Science.gov (United States)

    Segal, N L; MacDonald, K B

    1998-04-01

    Behavioral geneticists and evolutionary psychologists have generally pursued human behavioral analyses with little theoretical or methodological exchange. However, significant benefits might accrue from increased communication between these disciplines. The primary goals of this article are (1) to identify meaningful junctures between behavioral genetics and evolutionary psychology, (2) to describe behavioral genetic research designs and their applications to evolutionary analyses, and (3) to reassess current personality research in light of behavioral genetic and evolutionary concepts and techniques. The five-factor model of personality is conceptualized as subsuming variation in normative species-typical systems with adaptive functions in the human environment of evolutionary adaptation. Considered as universal evolved mechanisms, personality systems are often seen in dynamic conflict within individuals and as highly compartmentalized in their functioning between settings. However, genetically influenced individual differences in personality may also be understood within an evolutionary framework. Studies of the heritability of personality traits indicate broad-sense heritabilities in the 0.40-0.50 range with evidence of substantial nonadditive genetic variation and nonshared environmental influences. Evidence indicates that evolutionary theory (e.g., inclusive fitness theory) predicts patterns of social interaction (e.g., cooperation and bereavement) in relatives. Furthermore, variation in personality may constitute a range of viable strategies matching the opportunities available in the complex niche environment of human societies. Within this wide range of viable strategies, personality variation functions as a resource environment for individuals in the sense that personality variation is evaluated according to the interests of the evaluator (e.g., friendships, coalitions, or mate choice).

  9. Jealousy as a function of rival characteristics : An evolutionary perspective

    NARCIS (Netherlands)

    Dijkstra, P; Buunk, BP

    1998-01-01

    Following from om evolutionary psychology, men and women differ in the characteristics they value in a partner. Men value physical attractiveness in women because a woman's physical attractiveness is related to her fertility, whereas women value dominance in men since dominance is related to a man's

  10. Cooperation and conflict in cancer: An evolutionary perspective

    Directory of Open Access Journals (Sweden)

    Jonathan Featherston

    2012-09-01

    Full Text Available Evolutionary approaches to carcinogenesis have gained prominence in the literature and enhanced our understanding of cancer. However, an appreciation of neoplasia in the context of evolutionary transitions, particularly the transition from independent genes to a fullyintegrated genome, is largely absent. In the gene–genome evolutionary transition, mobile genetic elements (MGEs can be studied as the extant exemplars of selfish autonomous lowerlevel units that cooperated to form a higher-level, functionally integrated genome. Here,we discuss levels of selection in cancer cells. In particular, we examine the tension between gene and genome units of selection by examining the expression profiles of MGE domains in an array of human cancers. Overall, across diverse cancers, there is an aberrant expression of several families of mobile elements, including the most common MGE in the human genome, retrotransposon LINE 1. These results indicate an alternative life-history strategy for MGEs in the cancers studied. Whether the aberrant expression is the cause or effect oftumourigenesis is unknown, although some evidence suggests that dysregulation of MGEs can play a role in cancer origin and progression. These data are interpreted in combination with phylostratigraphic reports correlating the origin of cancer genes with multicellularity and other potential increases in complexity in cancer cell populations. Cooperation and conflict between individuals at the gene, genome and cell level provide an evolutionary medicineperspective of cancer that enhances our understanding of disease pathogenesis and treatment.

  11. Molecular evolution of a chordate specific family of G protein-coupled receptors

    OpenAIRE

    Leese Florian; Hatt Hanns; Pelz Thomas; Mayer Christoph; Kurtenbach Stefan; Neuhaus Eva M

    2011-01-01

    Abstract Background Chordate evolution is a history of innovations that is marked by physical and behavioral specializations, which led to the development of a variety of forms from a single ancestral group. Among other important characteristics, vertebrates obtained a well developed brain, anterior sensory structures, a closed circulatory system and gills or lungs as blood oxygenation systems. The duplication of pre-existing genes had profound evolutionary implications for the developmental ...

  12. Sex differences in self-regulation: an evolutionary perspective

    OpenAIRE

    Hosseini-Kamkar, Niki; Morton, J. Bruce

    2014-01-01

    Bjorklund and Kipp (1996) provide an evolutionary framework predicting that there is a female advantage in inhibition and self-regulation due to differing selection pressures placed on males and females. The majority of the present review will summarize sex differences in self-regulation at the behavioral level. The neural and hormonal underpinnings of this potential sexual dimorphism will also be investigated and the results of the experiments summarized will be related to the hypothesis adv...

  13. Why Shops Close Again : An Evolutionary Perspective on the Deregulation of Shopping Hours

    NARCIS (Netherlands)

    Kosfeld, M.

    1999-01-01

    This paper introduces a new perspective on the deregulation of shopping hours based on ideas from evolutionary game theory. We study a retail economy where shopping hours have been deregulated recently. It is argued that first, the deregulation leads to a coordination problem between store owners an

  14. The Nestor Effect: Extending Evolutionary Developmental Psychology to a Lifespan Perspective

    Science.gov (United States)

    Greve, Werner; Bjorklund, David F.

    2009-01-01

    We extend an evolutionary perspective of development to the lifespan, proposing that human longevity may be related to the experience, knowledge, and wisdom provided by older members of human groups. In addition to the assistance in childcare provided by grandmothers to their daughters, the experience of wise elders could have served to benefit…

  15. The future orientation of constructive memory: an evolutionary perspective on therapeutic hypnosis and brief psychotherapy.

    Science.gov (United States)

    Rossi, Ernest; Erickson-Klein, Roxanna; Rossi, Kathryn

    2008-04-01

    We explore a new distinction between the future, prospective memory system being investigated in current neuroscience and the past, retrospective memory system, which was the original theoretical foundation of therapeutic hypnosis, classical psychoanalysis, and psychotherapy. We then generalize a current evolutionary theory of sleep and dreaming, which focuses on the future, prospective memory system, to conceptualize a new evolutionary perspective on therapeutic hypnosis and brief psychotherapy. The implication of current neuroscience research is that activity-dependent gene expression and brain plasticity are the psychobiological basis of adaptive behavior, consciousness, and creativity in everyday life as well as psychotherapy. We summarize a case illustrating how this evolutionary perspective can be used to quickly resolve problems with past obstructive procrastination in school to facilitate current and future academic success. PMID:18524301

  16. Rethinking Oedipus: an evolutionary perspective of incest avoidance.

    Science.gov (United States)

    Erickson, M T

    1993-03-01

    The author presents a biological hypothesis of incest avoidance. Pertinent literature from evolutionary biology, ethology, anthropology, and clinical research is reviewed. Secure early bonding to immediate kin predicts later adaptive kin-directed behaviors, including preferential altruism (kin selection) and incest avoidance. Impaired bonding predicts aberrant kin-directed behavior, including diminished altruism, neglect, and an increased incidence of incest. Failed bonding predicts the highest frequency of incest. Secure bonding to kin may function to establish adaptive kin-directed behaviors, including incest avoidance. Bonding is conceived of as the developmental foundation of a form of social attraction, here called "familial attraction," which is evolutionarily distinct from sexual attraction.

  17. Perspective: Evolutionary design of granular media and block copolymer patterns

    Science.gov (United States)

    Jaeger, Heinrich M.; de Pablo, Juan J.

    2016-05-01

    The creation of new materials "by design" is a process that starts from desired materials properties and proceeds to identify requirements for the constituent components. Such process is challenging because it inverts the typical modeling approach, which starts from given micro-level components to predict macro-level properties. We describe how to tackle this inverse problem using concepts from evolutionary computation. These concepts have widespread applicability and open up new opportunities for design as well as discovery. Here we apply them to design tasks involving two very different classes of soft materials, shape-optimized granular media and nanopatterned block copolymer thin films.

  18. An evolutionary perspective on zinc uptake by human fungal pathogens†

    Science.gov (United States)

    Wilson, Duncan

    2015-01-01

    The mammalian immune system has evolved sophisticated mechanisms to withhold essential micronutrients from invading pathogens. These processes, collectively known as nutritional immunity serve to limit microbial proliferation and bolster killing of the invader. Successful pathogens, therefore, have developed strategies to counteract nutritional immunity and acquire essential micronutrients in the restrictive environment of the infected host. Here I take advantage of the now large number of sequenced fungal genomes to explore the zinc acquisition strategies of human fungal pathogens and reflect on the evolutionary context of these uptake pathways. PMID:25652414

  19. Sex differences in self-regulation: An evolutionary perspective

    Directory of Open Access Journals (Sweden)

    Niki eHosseini-Kamkar

    2014-08-01

    Full Text Available Bjorklund and Kipp (1996 provide an evolutionary framework predicting that there is a female advantage in inhibition and self-regulation due to differing selection pressures placed on males and females. The majority of the present review will summarize sex differences in self-regulation at the behavioral level. The neural and hormonal underpinnings of this potential sexual dimorphism will also be investigated and the results of the experiments summarized will be related to the hypothesis advanced by Bjorklund and Kipp (1996. Paradoxically, sex differences in self-regulation are more consistently reported in children prior to the onset of puberty. In adult cohorts, the results of studies examining sex differences in self-regulation are mixed. A few recent experiments suggesting that females are less impulsive than males only during fertile stages of the menstrual cycle will be reviewed. A brief discussion of an evolutionary framework proposing that it is adaptive for females to employ a self-regulatory behavioral strategy when fertile will follow.

  20. Bioinformatics education dissemination with an evolutionary problem solving perspective.

    Science.gov (United States)

    Jungck, John R; Donovan, Samuel S; Weisstein, Anton E; Khiripet, Noppadon; Everse, Stephen J

    2010-11-01

    Bioinformatics is central to biology education in the 21st century. With the generation of terabytes of data per day, the application of computer-based tools to stored and distributed data is fundamentally changing research and its application to problems in medicine, agriculture, conservation and forensics. In light of this 'information revolution,' undergraduate biology curricula must be redesigned to prepare the next generation of informed citizens as well as those who will pursue careers in the life sciences. The BEDROCK initiative (Bioinformatics Education Dissemination: Reaching Out, Connecting and Knitting together) has fostered an international community of bioinformatics educators. The initiative's goals are to: (i) Identify and support faculty who can take leadership roles in bioinformatics education; (ii) Highlight and distribute innovative approaches to incorporating evolutionary bioinformatics data and techniques throughout undergraduate education; (iii) Establish mechanisms for the broad dissemination of bioinformatics resource materials and teaching models; (iv) Emphasize phylogenetic thinking and problem solving; and (v) Develop and publish new software tools to help students develop and test evolutionary hypotheses. Since 2002, BEDROCK has offered more than 50 faculty workshops around the world, published many resources and supported an environment for developing and sharing bioinformatics education approaches. The BEDROCK initiative builds on the established pedagogical philosophy and academic community of the BioQUEST Curriculum Consortium to assemble the diverse intellectual and human resources required to sustain an international reform effort in undergraduate bioinformatics education. PMID:21036947

  1. Evolutionary perspectives of telomerase RNA structure and function.

    Science.gov (United States)

    Podlevsky, Joshua D; Chen, Julian J-L

    2016-08-01

    Telomerase is the eukaryotic solution to the 'end-replication problem' of linear chromosomes by synthesising the highly repetitive DNA constituent of telomeres, the nucleoprotein cap that protects chromosome termini. Functioning as a ribonucleoprotein (RNP) enzyme, telomerase is minimally composed of the highly conserved catalytic telomerase reverse transcriptase (TERT) and essential telomerase RNA (TR) component. Beyond merely providing the template for telomeric DNA synthesis, TR is an innate telomerase component and directly facilitates enzymatic function. TR accomplishes this by having evolved structural elements for stable assembly with the TERT protein and the regulation of the telomerase catalytic cycle. Despite its prominence and prevalence, TR has profoundly diverged in length, sequence, and biogenesis pathway among distinct evolutionary lineages. This diversity has generated numerous structural and mechanistic solutions for ensuring proper RNP formation and high fidelity telomeric DNA synthesis. Telomerase provides unique insights into RNA and protein coevolution within RNP enzymes. PMID:27359343

  2. Design principles of the human brain: an evolutionary perspective.

    Science.gov (United States)

    Hofman, Michel A

    2012-01-01

    The evolution of the brain in mammals has been accompanied by a reorganization of the brain as a result of differential growth of certain brain regions. Consequently, the geometry of the brain, and especially the size and shape of the cerebral cortex, has changed notably during evolution. Comparative studies of the cerebral cortex suggest that there are general architectural principles governing its growth and evolutionary development and that the primate neocortex is uniformly organized and composed of neural processing units. We are beginning to understand the geometric, biophysical, and energy constraints that have governed the evolution of these neuronal networks. In this review, some of the design principles and operational modes will be explored that underlie the information processing capacity of the cerebral cortex in primates, and it will be argued that with the evolution of the human brain we have nearly reached the limits of biological intelligence.

  3. Parasites and marine invasions: Ecological and evolutionary perspectives

    Science.gov (United States)

    Goedknegt, M. Anouk; Feis, Marieke E.; Wegner, K. Mathias; Luttikhuizen, Pieternella C.; Buschbaum, Christian; Camphuysen, Kees (C. J.); van der Meer, Jaap; Thieltges, David W.

    2016-07-01

    Worldwide, marine and coastal ecosystems are heavily invaded by introduced species and the potential role of parasites in the success and impact of marine invasions has been increasingly recognized. In this review, we link recent theoretical developments in invasion ecology with empirical studies from marine ecosystems in order to provide a conceptual framework for studying the role of parasites and their hosts in marine invasions. Based on an extensive literature search, we identified six mechanisms in which invaders directly or indirectly affect parasite and host populations and communities: I) invaders can lose some or all of their parasites during the invasion process (parasite release or reduction), often causing a competitive advantage over native species; II) invaders can also act as a host for native parasites, which may indirectly amplify the parasite load of native hosts (parasite spillback); III) invaders can also be parasites themselves and be introduced without needing co-introduction of the host (introduction of free-living infective stages); IV) alternatively, parasites may be introduced together with their hosts (parasite co-introduction with host); V) consequently, these co-introduced parasites can sometimes also infect native hosts (parasite spillover); and VI) invasive species may be neither a host nor a parasite, but nevertheless affect native parasite host interactions by interfering with parasite transmission (transmission interference). We discuss the ecological and evolutionary implications of each of these mechanisms and generally note several substantial effects on natural communities and ecosystems via i) mass mortalities of native populations creating strong selection gradients, ii) indirect changes in species interactions within communities and iii) trophic cascading and knock-on effects in food webs that may affect ecosystem function and services. Our review demonstrates a wide range of ecological and evolutionary implications of

  4. Evolutionary history of anglerfishes (Teleostei: Lophiiformes: a mitogenomic perspective

    Directory of Open Access Journals (Sweden)

    Shimazaki Mitsuomi

    2010-02-01

    Full Text Available Abstract Background The teleost order Lophiiformes, commonly known as the anglerfishes, contains a diverse array of marine fishes, ranging from benthic shallow-water dwellers to highly modified deep-sea midwater species. They comprise 321 living species placed in 68 genera, 18 families and 5 suborders, but approximately half of the species diversity is occupied by deep-sea ceratioids distributed among 11 families. The evolutionary origins of such remarkable habitat and species diversity, however, remain elusive because of the lack of fresh material for a majority of the deep-sea ceratioids and incompleteness of the fossil record across all of the Lophiiformes. To obtain a comprehensive picture of the phylogeny and evolutionary history of the anglerfishes, we assembled whole mitochondrial genome (mitogenome sequences from 39 lophiiforms (33 newly determined during this study representing all five suborders and 17 of the 18 families. Sequences of 77 higher teleosts including the 39 lophiiform sequences were unambiguously aligned and subjected to phylogenetic analysis and divergence time estimation. Results Partitioned maximum likelihood analysis confidently recovered monophyly for all of the higher taxa (including the order itself with the exception of the Thaumatichthyidae (Lasiognathus was deeply nested within the Oneirodidae. The mitogenomic trees strongly support the most basal and an apical position of the Lophioidei and a clade comprising Chaunacoidei + Ceratioidei, respectively, although alternative phylogenetic positions of the remaining two suborders (Antennarioidei and Ogcocephaloidei with respect to the above two lineages are statistically indistinguishable. While morphology-based intra-subordinal relationships for relatively shallow, benthic dwellers (Lophioidei, Antennarioidei, Ogcocephaloidei, Chaunacoidei are either congruent with or statistically indistinguishable from the present mitogenomic tree, those of the principally deep

  5. Hemichordates and the Origin of Chordates

    Science.gov (United States)

    Gerhart, John; Kirschner, Marc; Lowe, Chris

    2002-01-01

    At the start of the period of the NASA grant three years ago, we had no information on the organization and development of the body axis of the hemichordate, Saccoglossus kowalevskii. Now we have substantial findings about the anteroposterior axis and dorsoventral axis, and based on this information, we have new insights about the origin of chordates from ancestral deuterostomes. We found ways to obtain and preserve large numbers of embryos and hatched juveniles. We can now collect about 40,000 embryos in the month of September, the time of S. kowalevskii spawning at Woods Hole. Excellent cDNA libraries were prepared from three developmental stages. From these libraries, we directly isolated about 30 gene ortholog sequences by screening and pcr techniques, all of these sequences of interest in the inquiry about the animal's organization and development. We also performed a mid-sized EST project (60,000 randomly picked clones, many of these arrayed). About half of these have been analyzed so far by blastx and are suitable for direct use of clones. We have obtained about 50 interesting sequences from this set. The rest still await analysis. Thus, at this time we have isolated orthologs of 80 genes that are known to be expressed in chordates in conserved domains and known to have interesting roles in chordate organization and development. The orthology of the S. kowalevskii sequences has been verified by neighbor joining and parsimony methods, with bootstrap estimates of validity. The S. kowalevskii sequences cluster with other deuterostome sequences, namely, other hemichordates, echinoderms, ascidians, amphioxus, or vertebrates, depending on what sequences are available in the database for comparison. We have used these sequences to do high quality in situ hybridization on S. kowalevskii embryos, and the results can be divided into three sections-those concerning the anteroposterior axis of S. kowalevskii in comparison to the same axis of chordates, those concerning

  6. MARKETING OBJECTIVES OF RETAILERS WITH DIFFERENTIATED GOODS: AN EVOLUTIONARY PERSPECTIVE

    Institute of Scientific and Technical Information of China (English)

    Tiaojun XIAO; Gang YU

    2006-01-01

    In the real world, revenue maximization behavior may prevail in various markets. To understand this phenomenon, we develop a two-population model with two-vertically integrated channels. Every channel consists of one manufacturer and many (a sufficiently large number of) retailers that sell products in different markets by adopting pure marketing objective strategies: profit maximization and revenue maximization. We study the marketing objective behaviors in the quantity-setting duopoly and the price-setting duopoly situations respectively from an indirect evolutionary point of view. In the quantity-setting duopoly situation, we find that whether the equilibrium is an evolutionarily stable strategy depends on the type of strategic interaction (substitutes or complements), relative unit cost, market scale, etc. We extend it to the case with continuous preferences. We argue that revenue maximization may be an evolutionarily stable strategy and profit maximization strategy may be unstable. Under proper conditions, revenue maximization behavior can coexist with profit maximization behavior. In the price-setting duopoly situation with linear demand functions, we find that profit maximization is always an evolutionarily stable strategy and revenue maximization behavior will gradually become extinct. The extended model has a similar result but the retailers may compromise the two pure strategies.

  7. Lysosomal enzymes and their receptors in invertebrates: an evolutionary perspective.

    Science.gov (United States)

    Kumar, Nadimpalli Siva; Bhamidimarri, Poorna M

    2015-01-01

    Lysosomal biogenesis is an important process in eukaryotic cells to maintain cellular homeostasis. The key components that are involved in the biogenesis such as the lysosomal enzymes, their modifications and the mannose 6-phosphate receptors have been well studied and their evolutionary conservation across mammalian and non-mammalian vertebrates is clearly established. Invertebrate lysosomal biogenesis pathway on the other hand is not well studied. Although, details on mannose 6-phosphate receptors and enzymes involved in lysosomal enzyme modifications were reported earlier, a clear cut pathway has not been established. Recent research on the invertebrate species involving biogenesis of lysosomal enzymes suggests a possible conserved pathway in invertebrates. This review presents certain observations based on these processes that include biochemical, immunological and functional studies. Major conclusions include conservation of MPR-dependent pathway in higher invertebrates and recent evidence suggests that MPR-independent pathway might have been more prominent among lower invertebrates. The possible components of MPR-independent pathway that may play a role in lysosomal enzyme targeting are also discussed here.

  8. The ecology of cancer from an evolutionary game theory perspective.

    Science.gov (United States)

    Pacheco, Jorge M; Santos, Francisco C; Dingli, David

    2014-08-01

    The accumulation of somatic mutations, to which the cellular genome is permanently exposed, often leads to cancer. Analysis of any tumour shows that, besides the malignant cells, one finds other 'supporting' cells such as fibroblasts, immune cells of various types and even blood vessels. Together, these cells generate the microenvironment that enables the malignant cell population to grow and ultimately lead to disease. Therefore, understanding the dynamics of tumour growth and response to therapy is incomplete unless the interactions between the malignant cells and normal cells are investigated in the environment in which they take place. The complex interactions between cells in such an ecosystem result from the exchange of information in the form of cytokines- and adhesion-dependent interactions. Such processes impose costs and benefits to the participating cells that may be conveniently recast in the form of a game pay-off matrix. As a result, tumour progression and dynamics can be described in terms of evolutionary game theory (EGT), which provides a convenient framework in which to capture the frequency-dependent nature of ecosystem dynamics. Here, we provide a tutorial review of the central aspects of EGT, establishing a relation with the problem of cancer. Along the way, we also digress on fitness and of ways to compute it. Subsequently, we show how EGT can be applied to the study of the various manifestations and dynamics of multiple myeloma bone disease and its preceding condition known as monoclonal gammopathy of undetermined significance. We translate the complex biochemical signals into costs and benefits of different cell types, thus defining a game pay-off matrix. Then we use the well-known properties of the EGT equations to reduce the number of core parameters that characterize disease evolution. Finally, we provide an interpretation of these core parameters in terms of what their function is in the ecosystem we are describing and generate

  9. An evolutionary perspective on Internet adoption by retailers in the Netherlands

    OpenAIRE

    Ron A. Boschma; Jesse W J Weltevreden

    2006-01-01

    The paper analyses from an evolutionary perspective how retailers respond and adapt to b2c e-commerce. As such, the paper explores the diversity of behavior of retailers with respect to the adoption of e-commerce. More in particular, it examines empirically the extent to which the adoption of Internet strategies is affected by firm-specific features (e.g., habits of the entrepreneur, routines of firms), network relationships, and geographical proximity. Logistic regression analyses of 643 ind...

  10. New Early Cambrian Chordates from Haikou, Kunming

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Two new chordates, Cathaymyrus haikouensis Luo et Hu sp. nov. andZhongxiniscus intermedius Luo et Hu gen. et sp. nov. are studied in this paper. Both display numerous S-shaped myomeres on their trunk. C. haikouensis shows a long and slim body similar to that of Cathaymyrus diadexus Shu et al., Zhongxiniscus approaches to Myllokunmingia and Haikouichthvs in the dorsal fin, but differs in the myomeres. Zhongxiniscus may be the intermediate form between Ca thaymyrus and Myllokunmingia and Haikouichthys.

  11. Introduction to the special issue : Globalisation, knowledge and institutional change: Towards an evolutionary perspective to economic development

    NARCIS (Netherlands)

    Morrison, Andrea; Cusmano, Lucia

    2015-01-01

    This special issue aims at advancing the debate about the interpretative power of evolutionary perspectives on economic development and institutional change. In the introduction, we argue that the interpretative power of the current evolutionary approach can be improved by elaborating an 'augmented'

  12. Is evolutionary psychology a metatheory for psychology? A discussion of four major issues in psychology from an evolutionary developmental perspective

    NARCIS (Netherlands)

    A. Ploeger; H.L.J. van der Maas; M.E.J. Raijmakers

    2008-01-01

    Evolutionary psychology has been proposed as a metatheoretical framework for psychology. We argue that evolutionary psychology should be expanded if it is to offer new insights regarding the major issues in psychology. Evolutionary developmental biology can provide valuable new insights into issues

  13. The Middle Cambrian fossil Pikaia and the evolution of chordate swimming

    Directory of Open Access Journals (Sweden)

    Lacalli Thurston

    2012-07-01

    Full Text Available Abstract Conway Morris and Caron (2012 have recently published an account of virtually all the available information on Pikaia gracilens, a well-known Cambrian fossil and supposed basal chordate, and propose on this basis some new ideas about Pikaia’s anatomy and evolutionary significance. Chief among its chordate-like features are the putative myomeres, a regular series of vertical bands that extends the length of the body. These differ from the myomeres of living chordates in that boundaries between them (the myosepta are gently curved, with minimal overlap, whereas amphioxus and vertebrates have strongly overlapping V- and W-shaped myomeres. The implication, on biomechanical grounds, is that myomeres in Pikaia exerted much less tension on the myosepta, so the animal would have been incapable of swimming as rapidly as living chordates operating in the fast-twitch mode used for escape and attack. Pikaia either lacked the fast-twitch fibers necessary for such speeds, having instead only slow-twitch fibers, or it had an ancestral fiber type with functional capabilities more like modern slow fibers than fast ones. The first option is supported by the sequence of development in zebrafish, where both myoseptum formation and fast fiber deployment show a dependence on slow fibers, which develop first. For Pikaia, the absence of fast fibers has both behavioral and anatomical implications, which are discussed. Among the latter is the possibility that a notochord may not have been needed as a primary stiffening device if other structures (for example, the dorsal organ could perform that role.

  14. Classical and novel psychoactive substances: rethinking drug misuse from an evolutionary psychiatric perspective.

    Science.gov (United States)

    St John-Smith, Paul; McQueen, Daniel; Edwards, Lindsey; Schifano, Fabrizio

    2013-07-01

    In this article, ontogenetic and phylogenetic causes of drug abuse and links to human emotional development are considered. Some evolutionary perspectives (e.g. that under certain conditions, consumption of otherwise toxic alkaloids may confer both physical and cultural advantages) are reviewed. As described in the 'mismatch theory', the capacity of the human genome to evolve defences against toxins has been outstripped by the pace of cultural change and technological development, such as purposeful fermentation of alcohol and more recently distillation of alcohol; purification and chemical manipulation of plant alkaloids; and the engineering of entirely novel psychoactive substances (NPS). The functions of the neurobiological substrates that mediate substance misuse and dependence are reviewed. Reasons are given why NPSs present greater cause for concern than plant-derived substances of abuse. We argue that evolutionary biology provides an important orientation for the research agenda in substance misuse. PMID:23881888

  15. Into the Green Economy – Evolutionary Perspectives on Green Economic Change

    DEFF Research Database (Denmark)

    Andersen, Maj Munch

    cooperation. Firms, it is argued, do make each other go green as part of the economic process, entailing major in-stitutional and organizational changes which form important parts of the green economic evolution. The greening of the economy reflects important features of modern complex economic systems......The recent ‘greening’ of the economy represents possible one of the most profound examples of economic change. While the environment used to be considered a burden to business this perspec-tive has changed making ‘eco-innovation’ increasingly recognized as a driver of economic devel......-opment. Evolutionary economic research into the greening of industry and the economy is, howev-er, limited, so explanations of this dramatic change are lacking. This paper seeks to remedy this gap and forward evolutionary explanations and historical cases on the dynamics and scope of green economic change. The theme...

  16. The evolution of dopamine systems in chordates

    Directory of Open Access Journals (Sweden)

    Kei eYamamoto

    2011-03-01

    Full Text Available Dopamine (DA neurotransmission in the central nervous system (CNS is found throughout chordates, and its emergence predates the divergence of chordates. Many of the molecular components of DA systems, such as biosynthetic enzymes, transporters and receptors, are shared with those of other monoamine systems, suggesting the common origin of these systems. In the mammalian CNS, the DA neurotransmitter systems are diversified and serve for visual and olfactory perception, sensory-motor programming, motivation, memory, emotion, and endocrine regulations. Some of the functions are conserved among different vertebrate groups, while others are not, and this is reflected in the anatomical aspects of DA systems in the forebrain and midbrain. Recent findings concerning a second tyrosine hydroxylase gene (TH2 revealed new populations of DA synthesizing cells, as evidenced in the periventricular hypothalamic zones of teleost fish. It is likely that the ancestor of vertebrates possessed TH2 DA-synthesizing cells, and the TH2 gene has been lost secondarily in placental mammals. All the vertebrates possess DA cells in the olfactory bulb, retina and in the diencephalon. Midbrain DA cells are abundant in amniotes while absent in some groups, e.g. teleosts. Studies of protochordate DA cells suggest that the diencephalic DA cells were present before the divergence of the chordate lineage. In contrast, the midbrain cell populations have probably emerged in the vertebrate lineage following the development of the midbrain-hindbrain boundary. The functional flexibility of the DA systems, and the evolvability provided by duplication of the corresponding genes permitted a large diversification of these systems. These features were instrumental in the adaptation of brain functions to the very variable way of life of vertebrates.

  17. A Survey from the Perspective of Evolutionary Process in the Internet of Things

    OpenAIRE

    Feng Wang; Liang Hu; Jin Zhou; Kuo Zhao

    2015-01-01

    The title of this paper may suggest such topics as routing, networking, and data mining, but we focus on new research angles regarding the Internet of Things (IoT) as the theme of this paper. These research angles come from other disciplines and are in the process of being adopted by the IoT. Our paper serves a key purpose: from the perspective of correlative technologies based on time, to review the evolutionary process of the IoT and depict the relations between the correlation techniques w...

  18. An Evolutionary Perspective on the Importance of Community Relations for Quality of Life

    Directory of Open Access Journals (Sweden)

    Bjørn Grinde

    2009-01-01

    Full Text Available The evolutionary perspective is relevant for the study of quality of life in that the brain, including its capacity for positive and negative states of mind, has been shaped by the forces of evolution. The present text uses this perspective to discuss three questions related to the observation that human interactions are a particular important factor for well-being: (1 What is known about the inherent nature of our social propensities? (2 Is the present situation responsible for a suboptimal quality of life? (3 Are there alternatives to the organization of mainstream Western society? Based on this discussion, the question is raised as to whether it is possible to suggest improvements. Briefly, it seems possible to create conditions that enhance social relations and to the extent that happiness is considered an important objective, this is a relevant endeavor.

  19. Investigating evolutionary perspective of carcinogenesis with single-cell transcriptome analysis

    Institute of Scientific and Technical Information of China (English)

    Xi Zhang; Cheng Zhang; Zhongjun Li; Jiangjian Zhong; Leslie P. Weiner; Jiang F. Zhong

    2013-01-01

    We developed phase-switch microfluidic devices for molecular profiling of a large number of single cells. Whole genome microarrays and RNA-sequencing are commonly used to determine the expression levels of genes in cell lysates (a physical mix of millions of cells) for inferring gene functions. However, cellular heterogeneity becomes an inherent noise in the measurement of gene expression. The unique molecular characteristics of individual cells, as well as the temporal and quantitative information of gene expression in cells, are lost when averaged among all cells in cell lysates. Our single-cell technology overcomes this limitation and enables us to obtain a large number of single-cell transcriptomes from a population of cells. A collection of single-cell molecular profiles allows us to study carcinogenesis from an evolutionary perspective by treating cancer as a diverse population of cells with abnormal molecular characteristics. Because a cancer cellpopulation contains cells at various stages of development toward drug resistance, clustering similar single-cell molecular profiles could reveal how drug-resistant sub-clones evolve during cancer treatment. Here, we discuss how single-celltranscriptome analysis technology could enable the study of carcinogenesis from an evolutionary perspective and the development of drug-resistance in leukemia. The single-cell transcriptome analysis reported here could have a direct and significant impact on current cancer treatments and future personalized cancer therapies.

  20. The amphioxus genome and the evolution of the chordate karyotype

    Energy Technology Data Exchange (ETDEWEB)

    Putnam, Nicholas H.; Butts, Thomas; Ferrier, David E.K.; Furlong, Rebecca F.; Hellsten, Uffe; Kawashima, Takeshi; Robinson-Rechavi, Marc; Shoguchi, Eiichi; Terry, Astrid; Yu, Jr-Kai; Benito-Gutierrez, Elia; Dubchak, Inna; Garcia-Fernandez, Jordi; Gibson-Brown, Jeremy J.; Grigoriev, Igor V.; Horton, Amy C.; de Jong, Pieter J.; Jurka, Jerzy; Kapitonov, Vladimir; Kohara, Yuji; Kuroki, Yoko; Lindquist, Erika; Lucas, Susan; Osoegawa, Kazutoyo; Pennacchio, Len A.; Salamov, Asaf A.; Satou, Yutaka; Sauka-Spengler, Tatjana; Schmutz[, Jeremy; Shin-I, Tadasu; Toyoda, Atsushi; Bronner-Fraser, Marianne; Fujiyama, Asao; Holland, Linda Z.; Holland, Peter W. H.; Satoh, Nori; Rokhsar, Daniel S.

    2008-04-01

    Lancelets ('amphioxus') are the modern survivors of an ancient chordate lineage with a fossil record dating back to the Cambrian. We describe the structure and gene content of the highly polymorphic {approx}520 million base pair genome of the Florida lancelet Branchiostoma floridae, and analyze it in the context of chordate evolution. Whole genome comparisons illuminate the murky relationships among the three chordate groups (tunicates, lancelets, and vertebrates), and allow reconstruction of not only the gene complement of the last common chordate ancestor, but also a partial reconstruction of its genomic organization, as well as a description of two genome-wide duplications and subsequent reorganizations in the vertebrate lineage. These genome-scale events shaped the vertebrate genome and provided additional genetic variation for exploitation during vertebrate evolution.

  1. Retinoic acid signaling and the evolution of chordates

    OpenAIRE

    Marlétaz, Ferdinand; Holland, Linda Z; Laudet, Vincent; Schubert, Michael

    2006-01-01

    In chordates, which comprise urochordates, cephalochordates and vertebrates, the vitamin A-derived morphogen retinoic acid (RA) has a pivotal role during development. Altering levels of endogenous RA signaling during early embryology leads to severe malformations, mainly due to incorrect positional codes specifying the embryonic anteroposterior body axis. In this review, we present our current understanding of the RA signaling pathway and its roles during chordate development. In particular, ...

  2. Inversion of the chordate body axis: are there alternatives?

    Science.gov (United States)

    Gerhart, J.

    2000-01-01

    One major morphological difference between chordates and annelids or arthropods is the opposite orientation of the nerve cord and heart. A long-standing proposal is that the chordate axis evolved by inverting the body of an ancestor with the annelid/arthropod orientation. However, the data can also be explained by a common ancestor with diffuse dorsoventral organization, followed by oppositely directed condensation of the nerve cord and relocation of the heart in the two lines.

  3. Ascidians and the plasticity of the chordate developmental program

    OpenAIRE

    Lemaire, Patrick; Smith, William C.; Nishida, Hiroki

    2008-01-01

    Little is known about the ancient chordates that gave rise to the first vertebrates, but the descendants of other invertebrate chordates extant at the time still flourish in the ocean. These invertebrates include the cephalochordates and tunicates, whose larvae share with vertebrate embryos a common body plan with a central notochord and a dorsal nerve cord. Tunicates are now thought to be the sister group of vertebrates. However, research based on several species of ascidians, a diverse and ...

  4. Inversion of the chordate body axis: Are there alternatives?

    OpenAIRE

    Gerhart, J.

    2000-01-01

    One major morphological difference between chordates and annelids or arthropods is the opposite orientation of the nerve cord and heart. A long-standing proposal is that the chordate axis evolved by inverting the body of an ancestor with the annelid/arthropod orientation. However, the data can also be explained by a common ancestor with diffuse dorsoventral organization, followed by oppositely directed condensation of the nerve cord and relocation of the heart in the t...

  5. Chordate evolution and the three-phylum system

    OpenAIRE

    Satoh, Noriyuki; Rokhsar, Daniel; Nishikawa, Teruaki

    2014-01-01

    Traditional metazoan phylogeny classifies the Vertebrata as a subphylum of the phylum Chordata, together with two other subphyla, the Urochordata (Tunicata) and the Cephalochordata. The Chordata, together with the phyla Echinodermata and Hemichordata, comprise a major group, the Deuterostomia. Chordates invariably possess a notochord and a dorsal neural tube. Although the origin and evolution of chordates has been studied for more than a century, few authors have intimately discussed taxonomi...

  6. Questioning the bacterial overgrowth hypothesis of irritable bowel syndrome: an epidemiologic and evolutionary perspective.

    Science.gov (United States)

    Spiegel, Brennan M R

    2011-06-01

    Although studies indicate that small intestinal bacterial overgrowth (SIBO) is prevalent in irritable bowel syndrome (IBS), it remains unclear whether SIBO causes IBS. This review presents an epidemiologic and evolutionary inquiry that questions the bacterial overgrowth hypothesis of IBS, as follows. (1) Although the hypothesis may be biologically plausible, there is also a strong rationale for competing hypotheses; it is unlikely that SIBO is the predominant cause of IBS in all comers, because competing explanations are sensible and defensible. Moreover, data indicate that the test used to promulgate the SIBO hypothesis - the lactulose hydrogen breath test - may not have measured SIBO in the first place. (2) We do not have evidence of SIBO being absent before IBS symptoms, and present after IBS emerges. (3) There is not a dose-response relationship between small intestinal microbiota and IBS symptoms. (4) The relationship between SIBO and IBS is highly inconsistent among studies. (5) Many effective IBS therapies do not address SIBO at all, yet have a more favorable "number needed to treat" than antibiotics. (6) IBS does not behave like a traditional infectious disease, suggesting that microbes may not principally cause the syndrome. (7) Other factors may confound the relationship between SIBO and IBS, including proton pump inhibitors. (8) Whereas the brain-gut hypothesis is evolutionary sensible, the bacterial hypothesis is harder to defend from an evolutionary perspective. The article concludes that bacteria may contribute to some IBS symptoms, but that bacteria cannot be the only explanation, and a causal link between SIBO and IBS is not secure. PMID:21397724

  7. Evolutionary and neuropsychological perspectives on addictive behaviors and addictive substances: relevance to the "food addiction" construct

    Directory of Open Access Journals (Sweden)

    Davis C

    2014-12-01

    Full Text Available Caroline Davis School of Kinesiology and Health Science, York University, Toronto, ON, Canada Abstract: It has been argued that food cannot be "addictive", unlike conventional drugs of abuse, because it is an essential part of life. In this paper, evidence is reviewed, largely from an evolutionary psychobiological perspective, that plant-based psychoactive drugs (such as those derived from the opium poppy and the coca leaf and gambling-related behaviors were once adaptive for human health and survival in a similar manner as energy-based foods were for nourishment. "Evolutionary mismatch" viewpoints contend that certain behaviors were enhanced during the hunter-gatherer lifestyle – from which our genetic endowment had its origins – because they bestowed both survival and reproductive advantages to the species. However, in the context of advanced technology and other rapid environmental changes, these same behaviors have tended to become maladaptive and greatly overexpressed. Similar to the manufactured purification of psychotropic plant-based substances, the reward impact of processed and hyperpalatable foods, with their high levels of sugar, fat, and salt, is much increased from foods produced in nature. It is concluded therefore that what was once beneficial and necessary for our survival has been altered and ultraprocessed into edible products that may be disadvantageous and potentially addictive. Keywords: food addiction, evolution, drugs, gambling

  8. A CO-EVOLUTIONARY PERSPECTIVE AND ITS APPLICATION TO THE THEORY OF ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    Flavia Luciane Scherer

    2012-11-01

    Full Text Available This article pointed out the reasons and possibilities of co-evolutionary studies, requirements and problems to develop such studies, as well as discuss some of the central theoretical frameworks to the theory of organizations, from the perspective of coevolution (lewin and volberda , 1999. From this, we identify the possible links that can be established between different lenses of study, when integrated into a co-evolutionary study. Such links are drawn by taking the analysis of institutional theory (dimaggio and powell, 1991; meyer and rowan, 1991; scott, 1995, the transaction costs theory (williamson, 1981 and the theory of social relations in economic action (granovetter, 1992. Thus, it is expected to contribute to the discussion about the possibilities for greater integration in organizational studies, when calling attention to the importance of moving toward a more inclusive, taking into account the macro economic and social dynamics and their impact on the level the firm (in terms of effect size, identity, culture and learning processes and its inverse relationships - from the firm to the macro environment.

  9. LRRCE: a leucine-rich repeat cysteine capping motif unique to the chordate lineage

    Directory of Open Access Journals (Sweden)

    Bishop Paul N

    2008-12-01

    early chordate evolutionary origin for the LRRCE capping motif.

  10. A conserved non-reproductive GnRH system in chordates.

    Directory of Open Access Journals (Sweden)

    Takehiro G Kusakabe

    Full Text Available Gonadotropin-releasing hormone (GnRH is a neuroendocrine peptide that plays a central role in the vertebrate hypothalamo-pituitary axis. The roles of GnRH in the control of vertebrate reproductive functions have been established, while its non-reproductive function has been suggested but less well understood. Here we show that the tunicate Ciona intestinalis has in its non-reproductive larval stage a prominent GnRH system spanning the entire length of the nervous system. Tunicate GnRH receptors are phylogenetically closest to vertebrate GnRH receptors, yet functional analysis of the receptors revealed that these simple chordates have evolved a unique GnRH system with multiple ligands and receptor heterodimerization enabling complex regulation. One of the gnrh genes is conspicuously expressed in the motor ganglion and nerve cord, which are homologous structures to the hindbrain and spinal cord of vertebrates. Correspondingly, GnRH receptor genes were found to be expressed in the tail muscle and notochord of embryos, both of which are phylotypic axial structures along the nerve cord. Our findings suggest a novel non-reproductive role of GnRH in tunicates. Furthermore, we present evidence that GnRH-producing cells are present in the hindbrain and spinal cord of the medaka, Oryzias latipes, thereby suggesting the deep evolutionary origin of a non-reproductive GnRH system in chordates.

  11. Ion channel clustering at the axon initial segment and node of Ranvier evolved sequentially in early chordates.

    Directory of Open Access Journals (Sweden)

    Alexis S Hill

    2008-12-01

    Full Text Available In many mammalian neurons, dense clusters of ion channels at the axonal initial segment and nodes of Ranvier underlie action potential generation and rapid conduction. Axonal clustering of mammalian voltage-gated sodium and KCNQ (Kv7 potassium channels is based on linkage to the actin-spectrin cytoskeleton, which is mediated by the adaptor protein ankyrin-G. We identified key steps in the evolution of this axonal channel clustering. The anchor motif for sodium channel clustering evolved early in the chordate lineage before the divergence of the wormlike cephalochordate, amphioxus. Axons of the lamprey, a very primitive vertebrate, exhibited some invertebrate features (lack of myelin, use of giant diameter to hasten conduction, but possessed narrow initial segments bearing sodium channel clusters like in more recently evolved vertebrates. The KCNQ potassium channel anchor motif evolved after the divergence of lampreys from other vertebrates, in a common ancestor of shark and humans. Thus, clustering of voltage-gated sodium channels was a pivotal early innovation of the chordates. Sodium channel clusters at the axon initial segment serving the generation of action potentials evolved long before the node of Ranvier. KCNQ channels acquired anchors allowing their integration into pre-existing sodium channel complexes at about the same time that ancient vertebrates acquired myelin, saltatory conduction, and hinged jaws. The early chordate refinements in action potential mechanisms we have elucidated appear essential to the complex neural signaling, active behavior, and evolutionary success of vertebrates.

  12. Maternal capital and the metabolic ghetto: An evolutionary perspective on the transgenerational basis of health inequalities.

    Science.gov (United States)

    Wells, Jonathan C K

    2010-01-01

    There is particular interest in understanding socioeconomic and ethnic variability in health status. The developmental origins of disease hypothesis emphasize the importance of growth patterns across the life-course in relation to noncommunicable disease risk. The physiological components of cardiovascular risk, collectively termed the metabolic syndrome, derive in part from a disparity between the homeostatic "metabolic capacity" of vital organs and the "metabolic load" induced by large tissue masses, a rich diet and sedentary behavior. From an evolutionary perspective, the risk of such disparity is decreased by maternal physiology regulating offspring growth trajectory during gestation and lactation. Maternal capital, defined as phenotypic resources enabling investment in the offspring, allows effective buffering of the offspring from nutritional perturbations and represents the environmental niche initially occupied by the offspring. Offspring growth patterns are sensitive to the magnitude of maternal capital during early windows of plasticity. Offspring life-history strategy can then respond adaptively to further factors across the life-course, but only within the context of this initial maternal influence on growth. Maternal somatic capital is primarily gained or lost across generations, through variable rates of fetal and infant growth. I argue that the poor nutritional experience of populations subjected to colonialism resulted in a systematic loss of maternal capital, reflected in downward secular trends in stature. Accelerating the recovery of somatic capital within generations overloads metabolic capacity and exacerbates cardiovascular risk, reflected in increased disease rates in urbanizing and emigrant populations. Public health policies need to benefit metabolic capacity without exacerbating metabolic load.

  13. An Evolutionary Perspective of Nutrition and Inflammation as Mechanisms of Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    María Esther Rubio-Ruiz

    2015-01-01

    Full Text Available When cardiovascular diseases are viewed from an evolutionary biology perspective, a heightened thrifty and an inflammatory design could be their mechanisms. Human ancestors confronted a greater infectious load and were subjected to the selection for proinflammatory genes and a strong inflammatory function. Ancestors also faced starvation periods that pressed for a thrifty genotype which caused fat accumulation. The pressure of sustaining gluconeogenesis during periods of poor nourishment selected individuals with insulin resistance. Obesity induces a proinflammatory state due to the secretion of adipokines which underlie cardiometabolic diseases. Our actual lifestyle needs no more of such proinflammatory and thrifty genotypes and these ancestral genes might increase predisposition to diseases. Risk factors for atherosclerosis and diabetes are based on inflammatory and genetic foundations that can be accounted for by excess fat. Longevity has also increased in recent times and is related to a proinflammatory response with cardiovascular consequences. If human ancestral lifestyle could be recovered by increasing exercise and adapting a calorie restriction diet, obesity would decrease and the effects on chronic low-grade inflammation would be limited. Thereby, the rates of both atherosclerosis and diabetes could be reduced.

  14. Neurodevelopmental Plasticity in Pre- and Postnatal Environmental Interactions: Implications for Psychiatric Disorders from an Evolutionary Perspective

    Directory of Open Access Journals (Sweden)

    Young-A Lee

    2015-01-01

    Full Text Available Psychiatric disorders are disadvantageous behavioral phenotypes in humans. Accordingly, a recent epidemiological study has reported decreased fecundity in patients with psychiatric disorders, such as schizophrenia and autism spectrum disorders. Moreover, the fecundity of the relatives of these patients is not exceedingly higher compared to the fecundity of the relatives of normal subjects. Collectively, the prevalence of psychiatric disorders among humans is expected to decrease over generations. Nevertheless, in reality, the prevalence rates of psychiatric disorders in humans either have been constant over a long period of time or have even increased more recently. Several attempts to explain this fact have been made using biological mechanisms, such as de novo gene mutations or variants, although none of these explanations is fully comprehensive. Here, we propose a hypothesis towards understanding the biological mechanisms of psychiatric disorders from evolutionary perspectives. This hypothesis considers that behavioral phenotypes associated with psychiatric disorders might have emerged in the evolution of organisms as a neurodevelopmental adaptation against adverse environmental conditions associated with stress.

  15. Critical thinking: concept analysis from the perspective of Rodger's evolutionary method of concept analysis

    Science.gov (United States)

    Carbogim, Fábio da Costa; de Oliveira, Larissa Bertacchini; Püschel, Vilanice Alves de Araújo

    2016-01-01

    ABSTRACT Objective: to analyze the concept of critical thinking (CT) in Rodger's evolutionary perspective. Method: documentary research undertaken in the Cinahl, Lilacs, Bdenf and Dedalus databases, using the keywords of 'critical thinking' and 'Nursing', without limitation based on year of publication. The data were analyzed in accordance with the stages of Rodger's conceptual model. The following were included: books and articles in full, published in Portuguese, English or Spanish, which addressed CT in the teaching and practice of Nursing; articles which did not address aspects related to the concept of CT were excluded. Results: the sample was made up of 42 works. As a substitute term, emphasis is placed on 'analytical thinking', and, as a related factor, decision-making. In order, the most frequent preceding and consequent attributes were: ability to analyze, training of the student nurse, and clinical decision-making. As the implications of CT, emphasis is placed on achieving effective results in care for the patient, family and community. Conclusion: CT is a cognitive skill which involves analysis, logical reasoning and clinical judgment, geared towards the resolution of problems, and standing out in the training and practice of the nurse with a view to accurate clinical decision-making and the achieving of effective results. PMID:27598376

  16. What can other animals tell us about human social cognition? An evolutionary perspective on reflective and reflexive processing

    OpenAIRE

    Hecht, E. E.; Patterson, R.; Barbey, A. K.

    2012-01-01

    Human neuroscience has seen a recent boom in studies on reflective, controlled, explicit social cognitive functions like imitation, perspective-taking, and empathy. The relationship of these higher-level functions to lower-level, reflexive, automatic, implicit functions is an area of current research. As the field continues to address this relationship, we suggest that an evolutionary, comparative approach will be useful, even essential. There is a large body of research on reflexive, automat...

  17. Evolution of the organizer and the chordate body plan

    Science.gov (United States)

    Gerhart, J.

    2001-01-01

    The discovery of the organizer by Spemann and Mangold in 1924 raised two kinds of questions: those about the means of patterning the chordate body axis and those about the mechanisms of cell determination by induction. Some researchers, stressing the second, have suggested over the years that the organizer is poorly named and doesn't really organize because inducers act permissively, because they are not unique to the organizer, and because multipotent responsive cells develop complex local differentiations under artificial conditions. Furthermore, with the discovery of meso-endoderm induction in 1969, the possibility arose that this earlier induction generates as much organization as, or more than, does the organizer itself. Evidence is summarized in this article that the organizer does fulfill its title with regard to pattern formation: it adds greatly to embryonic organization by providing information about time, place, scale, and orientation for development by nearby members of the large multipotent competence groups surrounding the organizer. Embryos having smaller or larger organizers due to experimental intervention develop defective axial organization. Without an organizer the embryo develops no body axis and none of the four chordate characters: the notochord, gill slits, dorsal hollow nerve chord, and post-anal tail. For normal axis formation, the organizer's tripartite organization is needed. Each part differs in inducers, morphogenesis, and self-differentiation. The organizer is a trait of development of all members of the chordate phylum. In comparison to hemichordates, which constitute a phylum with some similarities to chordates, the chordamesoderm part is unique to the chordate organizer (the trunk-tail organizer). Its convergent extension displaces the gastrula posterior pole from alignment with the animal-vegetal axis and generates a new anteroposterior axis orthogonal to this old one. Once it has extended to full length, its signaling modifies

  18. Is capitalism in our genes? Competition, cooperation and the idea of homo oeconomicus from an evolutionary perspective

    Directory of Open Access Journals (Sweden)

    Portera Mariagrazia

    2016-01-01

    Full Text Available In the last few years a growing number of academic disciplines in the Humanities and Social Sciences have turned to the evolutionary approach: Evolutionary Economics, among these disciplines, is a thriving subfield of Economics, which adopts Darwin’s evolutionary ideas and concepts for the understanding of economic system and modes of production. Evolutionary hypotheses such as the „selfish gene“ idea, the ideas of „inclusive fitness“, „struggle for life“ and „survival of the fittest“ may suggest - and have indeed suggested - that humans are rational self-interest individuals, doing what they can to increase their own reproductive chances or at least the chances of their close relatives („inclusive fitness“. To put it differently, evolutionary theory seems to suggest that capitalism (in a broad sense is a system that has co-evolved with humans and best fits our evolved psychology. Is this the whole story? Is capitalism „in our genes“? In this paper I argue that conclusions such as „we are born to be rational self-interested agents“ or „capitalism is encoded in our genome“ are the result of a misleading application of Darwin’s evolutionary theory to human socio-economic processes, mainly to justify a (Western society based on selfish principles, but which is not naturally selfish in itself. Evolution seems to be the result of cooperative, not only (or not mainly competitive processes, and the model of Homo oeconomicus, that is the idea that humans are rational self-interested agents always trying to maximize profit, is, also from an bio-evolutionary perspective, nothing more than a fictional exercise.

  19. Evolutionary mitogenomics of Chordata: the strange case of ascidians and vertebrates

    OpenAIRE

    C Gissi; F. Griggio; F Iannelli

    2009-01-01

    The availability of almost one thousand complete mitochondrial genome (mtDNA) sequences of chordates provides an almost unique opportunity to analyse the evolution of this genome in the phylum Chordata, and to identify possible divergent evolutionary trends followed by the three chordate subphyla: Vertebrata, Cephalochordata and Tunicata.Here, we review some genome-level features of mtDNA, such as genetic code, gene content, genome architecture and gene strand asymmetry, mostly focusing on di...

  20. Evolutionary perspectives on human personality. Comment on "Personality from a cognitive-biological perspective" by Y. Neuman

    Science.gov (United States)

    Southard, Ashton C.; Zeigler-Hill, Virgil; Shackelford, Todd K.

    2014-12-01

    Yair Neuman [6] presents many provocative ideas in his interdisciplinary approach to human personality. In this commentary, we focus on his ideas regarding (1) the evolutionary basis of personality and (2) human sperm competition.

  1. Role of Body Fat and Body Shape on Judgment of Female Health and Attractiveness: An Evolutionary Perspective

    OpenAIRE

    Devendra Singh; Dorian Singh

    2006-01-01

    The main aim of this paper is to present an evolutionary perspective for why women’s attractiveness is assigned a great importance in practically all human societies. We present the data that the woman’s body shape, or hourglass figure as defined by the size of waist-to-hip-ratio (WHR), reliably conveys information about a woman’s age, fertility, and health and that systematic variation in women’s WHR invokes systematic changes in attractiveness judgment by participants both in Western and no...

  2. A Co-evolutionary perspective on the Drivers of International Sourcing of Pharmaceutical R&D to India

    DEFF Research Database (Denmark)

    Haakonsson, Stine Jessen; Ørberg Jensen, Peter D.; M. Mudambi, Susan

    2013-01-01

    The attractiveness of the Indian pharmaceutical industry as a destination for R&D sourcing by multinational corporations (MNCs) has evolved over the past decades. This evolution has coincided with changes in MNC strategies regarding sourcing location and governance modes. We propose a co......-evolutionary theory perspective embracing both firm-internal and firm-environmental factors for location attractiveness, along with institutional and industry changes. The framework integrates constructs from past research in economic geography, international business, and R&D internationalization. The Indian case...... illustrates how host-country institutional evolution, notably regarding intellectual property rights and education, plays a significant role for international sourcing of pharmaceutical R&D....

  3. Conservation and diversification of an ancestral chordate gene regulatory network for dorsoventral patterning.

    Directory of Open Access Journals (Sweden)

    Iryna Kozmikova

    Full Text Available Formation of a dorsoventral axis is a key event in the early development of most animal embryos. It is well established that bone morphogenetic proteins (Bmps and Wnts are key mediators of dorsoventral patterning in vertebrates. In the cephalochordate amphioxus, genes encoding Bmps and transcription factors downstream of Bmp signaling such as Vent are expressed in patterns reminiscent of those of their vertebrate orthologues. However, the key question is whether the conservation of expression patterns of network constituents implies conservation of functional network interactions, and if so, how an increased functional complexity can evolve. Using heterologous systems, namely by reporter gene assays in mammalian cell lines and by transgenesis in medaka fish, we have compared the gene regulatory network implicated in dorsoventral patterning of the basal chordate amphioxus and vertebrates. We found that Bmp but not canonical Wnt signaling regulates promoters of genes encoding homeodomain proteins AmphiVent1 and AmphiVent2. Furthermore, AmphiVent1 and AmphiVent2 promoters appear to be correctly regulated in the context of a vertebrate embryo. Finally, we show that AmphiVent1 is able to directly repress promoters of AmphiGoosecoid and AmphiChordin genes. Repression of genes encoding dorsal-specific signaling molecule Chordin and transcription factor Goosecoid by Xenopus and zebrafish Vent genes represents a key regulatory interaction during vertebrate axis formation. Our data indicate high evolutionary conservation of a core Bmp-triggered gene regulatory network for dorsoventral patterning in chordates and suggest that co-option of the canonical Wnt signaling pathway for dorsoventral patterning in vertebrates represents one of the innovations through which an increased morphological complexity of vertebrate embryo is achieved.

  4. Anteroposterior patterning in hemichordates and the origins of the chordate nervous system

    Science.gov (United States)

    Lowe, Christopher J.; Wu, Mike; Salic, Adrian; Evans, Louise; Lander, Eric; Stange-Thomann, Nicole; Gruber, Christian E.; Gerhart, John; Kirschner, Marc

    2003-01-01

    The chordate central nervous system has been hypothesized to originate from either a dorsal centralized, or a ventral centralized, or a noncentralized nervous system of a deuterostome ancestor. In an effort to resolve these issues, we examined the hemichordate Saccoglossus kowalevskii and studied the expression of orthologs of genes that are involved in patterning the chordate central nervous system. All 22 orthologs studied are expressed in the ectoderm in an anteroposterior arrangement nearly identical to that found in chordates. Domain topography is conserved between hemichordates and chordates despite the fact that hemichordates have a diffuse nerve net, whereas chordates have a centralized system. We propose that the deuterostome ancestor may have had a diffuse nervous system, which was later centralized during the evolution of the chordate lineage.

  5. Amphioxus: a peaceful anchovy fillet to illuminate Chordate Evolution (II

    Directory of Open Access Journals (Sweden)

    Jordi Garcia-Fernàndez

    2006-01-01

    Full Text Available The genome of the amphioxus is on the horizon. With Linda Holland and Jeremy Gibson-Brown at the forefront, with all the amphioxus community behind, and with the Joint Genome Institute, the amphioxus genome will see the light this year, 2006. Hope that it will reflect the “prototypical” preduplicative genome of vertebrates. It may answer definitively what the human genome did not: Are we vertebrates octaploid? Will it shed light on the novelties that helped non-chordates to be chordates? And more, will amphioxus, with a simpler genome, be developed to a senior “experimental model system”, allowing the testing of molecular functions in a non-duplicated genome background and allowing genetic modification to “recapitulate” evolution? Thanks to an outstanding collaboration between labs, the laboratory culture of amphioxus is underway after years of hard work in the field. 2007 looks promising for amphioxus research.

  6. Genetic and Genomic Toolbox of the Chordate Ciona intestinalis

    OpenAIRE

    Stolfi, Alberto; Christiaen, Lionel

    2012-01-01

    The experimental malleability and unique phylogenetic position of the sea squirt Ciona intestinalis as part of the sister group to the vertebrates have helped establish these marine chordates as model organisms for the study of developmental genetics and evolution. Here we summarize the tools, techniques, and resources available to the Ciona geneticist, citing examples of studies that employed such strategies in the elucidation of gene function in Ciona. Genetic screens, germline transgenesis...

  7. Vertebrate-like regeneration in the invertebrate chordate amphioxus

    OpenAIRE

    Somorjai, Ildikó M. L.; Rajmund L. Somorjai; Garcia-Fernàndez, Jordi; Escrivà, Hector

    2011-01-01

    An important question in biology is why some animals are able to regenerate, whereas others are not. The basal chordate amphioxus is uniquely positioned to address the evolution of regeneration. We report here the high regeneration potential of the European amphioxus Branchiostoma lanceolatum. Adults regenerate both anterior and posterior structures, including neural tube, notochord, fin, and muscle. Development of a classifier based on tail regeneration profiles predicts the assignment of yo...

  8. Conservation of Notochord Gene Expression Across Chordates: Insights From the Leprecan Gene Family

    OpenAIRE

    Capellini, Terence D.; Dunn, Matthew P.; Yale J Passamaneck; Selleri, Licia; Di Gregorio, Anna

    2008-01-01

    The notochord is a defining character of the chordates, and the T-box transcription factor Brachyury has been shown to be required for notochord development in all chordates examined. In the ascidian Ciona intestinalis, at least 44 notochord genes have been identified as bona fide transcriptional targets of Brachyury. We examined the embryonic expression of a subset of murine orthologs of Ciona Brachyury target genes in the notochord to assess its conservation throughout chordate evolution. W...

  9. Some assembly required: evolutionary and systems perspectives on the mammalian reproductive system.

    Science.gov (United States)

    Mordhorst, Bethany R; Wilson, Miranda L; Conant, Gavin C

    2016-01-01

    In this review, we discuss the way that insights from evolutionary theory and systems biology shed light on form and function in mammalian reproductive systems. In the first part of the review, we contrast the rapid evolution seen in some reproductive genes with the generally conservative nature of development. We discuss directional selection and coevolution as potential drivers of rapid evolution in sperm and egg proteins. Such rapid change is very different from the highly conservative nature of later embryo development. However, it is not unique, as some regions of the sex chromosomes also show elevated rates of evolutionary change. To explain these contradictory trends, we argue that it is not reproductive functions per se that induce rapid evolution. Rather, it is the fact that biotic interactions, such as speciation events and sexual conflict, have no evolutionary endpoint and hence can drive continuous evolutionary changes. Returning to the question of sex chromosome evolution, we discuss the way that recent advances in evolutionary genomics and systems biology and, in particular, the development of a theory of gene balance provide a better understanding of the evolutionary patterns seen on these chromosomes. We end the review with a discussion of a surprising and incompletely understood phenomenon observed in early embryos: namely the Warburg effect, whereby glucose is fermented to lactate and alanine rather than respired to carbon dioxide. We argue that evolutionary insights, from both yeasts and tumor cells, help to explain the Warburg effect, and that new metabolic modeling approaches are useful in assessing the potential sources of the effect.

  10. Acquisition of the dorsal structures in chordate amphioxus

    Science.gov (United States)

    Morov, Arseniy R.; Ukizintambara, Tharcisse; Sabirov, Rushan M.

    2016-01-01

    Acquisition of dorsal structures, such as notochord and hollow nerve cord, is likely to have had a profound influence upon vertebrate evolution. Dorsal formation in chordate development thus has been intensively studied in vertebrates and ascidians. However, the present understanding does not explain how chordates acquired dorsal structures. Here we show that amphioxus retains a key clue to answer this question. In amphioxus embryos, maternal nodal mRNA distributes asymmetrically in accordance with the remodelling of the cortical cytoskeleton in the fertilized egg, and subsequently lefty is first expressed in a patch of blastomeres across the equator where wnt8 is expressed circularly and which will become the margin of the blastopore. The lefty domain co-expresses zygotic nodal by the initial gastrula stage on the one side of the blastopore margin and induces the expression of goosecoid, not-like, chordin and brachyury1 genes in this region, as in the oral ectoderm of sea urchin embryos, which provides a basis for the formation of the dorsal structures. The striking similarity in the gene regulations and their respective expression domains when comparing dorsal formation in amphioxus and the determination of the oral ectoderm in sea urchin embryos suggests that chordates derived from an ambulacrarian-type blastula with dorsoventral inversion. PMID:27307516

  11. Acquisition of the dorsal structures in chordate amphioxus.

    Science.gov (United States)

    Morov, Arseniy R; Ukizintambara, Tharcisse; Sabirov, Rushan M; Yasui, Kinya

    2016-06-01

    Acquisition of dorsal structures, such as notochord and hollow nerve cord, is likely to have had a profound influence upon vertebrate evolution. Dorsal formation in chordate development thus has been intensively studied in vertebrates and ascidians. However, the present understanding does not explain how chordates acquired dorsal structures. Here we show that amphioxus retains a key clue to answer this question. In amphioxus embryos, maternal nodal mRNA distributes asymmetrically in accordance with the remodelling of the cortical cytoskeleton in the fertilized egg, and subsequently lefty is first expressed in a patch of blastomeres across the equator where wnt8 is expressed circularly and which will become the margin of the blastopore. The lefty domain co-expresses zygotic nodal by the initial gastrula stage on the one side of the blastopore margin and induces the expression of goosecoid, not-like, chordin and brachyury1 genes in this region, as in the oral ectoderm of sea urchin embryos, which provides a basis for the formation of the dorsal structures. The striking similarity in the gene regulations and their respective expression domains when comparing dorsal formation in amphioxus and the determination of the oral ectoderm in sea urchin embryos suggests that chordates derived from an ambulacrarian-type blastula with dorsoventral inversion. PMID:27307516

  12. Evolution of the reproductive endocrine system in chordates.

    Science.gov (United States)

    Kubokawa, Kaoru; Tando, Yukiko; Roy, Sonali

    2010-07-01

    The cephalochordate, amphioxus, is phylogenetically placed at the most primitive position in the chordate clade. Despite many studies on the endocrine system of amphioxus, definitive evidence has not been reported for the presence an endocrine system comparable to the pituitary-gonadal axis, which is important in the regulation of reproduction in vertebrates. Recent genome analyses in the amphioxus, Branchiostoma floridae, showed that it does not have any pituitary hormone genes except the thyrostimulin gene. Thyrostimulin is a heterodimeric glycoprotein hormone consisting of α and β subunits, and is present in various organs of vertebrates. Analyses of a phylogenetic tree and a synteny suggest that amphioxus' thyrostimulin is an ancestral type of the glycoprotein hormones in chordates. In addition, genes for sex steroidogenic enzymes belonging to the CYP family were found in the genome sequences. The conversion pathway of sex steroids from cholesterol to estrogen, androgen, and major sex steroids was also identified in the gonads of amphioxus in vitro. Furthermore, we demonstrated the expression of genes encoding thyrostimulin and sex steroidogenic enzymes by an in situ hybridization technique. Here, we discuss the evolution of hormones and reproductive functions in the neuroendocrine control system of chordates.

  13. The Role of Affordances in the Evolutionary Process Reconsidered A Niche Construction Perspective

    NARCIS (Netherlands)

    Withagen, Rob; van Wermeskerken, Margot

    2010-01-01

    Gibson asserted that affordances are the primary objects of perception. Although this assertion is especially attractive when considered in the context of evolutionary theory, the role that affordances play in the evolution of animals' perceptual and action systems is still unclear. Trying to combin

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

    NARCIS (Netherlands)

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

    2005-01-01

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

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

    NARCIS (Netherlands)

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

    2005-01-01

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

  16. War, Trauma and Children's Development: Observations from a Modern Evolutionary Perspective

    Science.gov (United States)

    Belsky, Jay

    2008-01-01

    Lethal intergroup conflict has been part of the human experience ever since our species emerged on the African savannah. Modern evolutionary thinking suggests that children's development could have evolved a variety of responses to it, some of which are highlighted upon considering, from the field of behavioural ecology, life-history theory and,…

  17. Judgments about Cooperators and Freeriders on a Shuar Work Team: An Evolutionary Psychological Perspective

    Science.gov (United States)

    Price, Michael E.

    2006-01-01

    Evolutionary biological theories of group cooperation predict that (1) group members will tend to judge cooperative co-members favorably, and freeriding co-members negatively and (2) members who themselves cooperate more frequently will be especially likely to make these social judgments. An experiment tested these predictions among Shuar…

  18. Roles of retinoic acid and Tbx1/10 in pharyngeal segmentation: amphioxus and the ancestral chordate condition

    OpenAIRE

    Koop, Demian; Chen, Jie; Theodosiou, Maria; Carvalho, João E; Alvarez, Susana; de Lera, Angel R.; Holland, Linda Z.; Schubert, Michael

    2014-01-01

    Background Although chordates descend from a segmented ancestor, the evolution of head segmentation has been very controversial for over 150 years. Chordates generally possess a segmented pharynx, but even though anatomical evidence and gene expression analyses suggest homologies between the pharyngeal apparatus of invertebrate chordates, such as the cephalochordate amphioxus, and vertebrates, these homologies remain contested. We, therefore, decided to study the evolution of the chordate hea...

  19. Getting to global: An evolutionary perspective of brand expansion in international markets

    OpenAIRE

    Janell D Townsend; Sengun Yeniyurt; Mehmet Berk Talay

    2009-01-01

    The globalization of brands is an evolutionary process that is determined by environmental and firm-level factors, including a brand's position in the firm's global brand architecture. A framework is developed incorporating aspects of environmental uncertainty, mimetic behavior, and experiential learning as they relate to the globalization of brands. Global brand architecture is introduced as an important strategic consideration of a brand's position and stage of internationalization. The hyp...

  20. Evolutionary origin and phylogeny of the modern holocephalans (Chondrichthyes: Chimaeriformes): a mitogenomic perspective.

    Science.gov (United States)

    Inoue, Jun G; Miya, Masaki; Lam, Kevin; Tay, Boon-Hui; Danks, Janine A; Bell, Justin; Walker, Terrence I; Venkatesh, Byrappa

    2010-11-01

    With our increasing ability for generating whole-genome sequences, comparative analysis of whole genomes has become a powerful tool for understanding the structure, function, and evolutionary history of human and other vertebrate genomes. By virtue of their position basal to bony vertebrates, cartilaginous fishes (class Chondrichthyes) are a valuable outgroup in comparative studies of vertebrates. Recently, a holocephalan cartilaginous fish, the elephant shark, Callorhinchus milii (Subclass Holocephali: Order Chimaeriformes), has been proposed as a model genome, and low-coverage sequence of its genome has been generated. Despite such an increasing interest, the evolutionary history of the modern holocephalans-a previously successful and diverse group but represented by only 39 extant species-and their relationship with elasmobranchs and other jawed vertebrates has been poorly documented largely owing to a lack of well-preserved fossil materials after the end-Permian about 250 Ma. In this study, we assembled the whole mitogenome sequences for eight representatives from all the three families of the modern holocephalans and investigated their phylogenetic relationships and evolutionary history. Unambiguously aligned sequences from these holocephalans together with 17 other vertebrates (9,409 nt positions excluding entire third codon positions) were subjected to partitioned maximum likelihood analysis. The resulting tree strongly supported a single origin of the modern holocephalans and their sister-group relationship with elasmobranchs. The mitogenomic tree recovered the most basal callorhinchids within the chimaeriforms, which is sister to a clade comprising the remaining two families (rhinochimaerids and chimaerids). The timetree derived from a relaxed molecular clock Bayesian method suggests that the holocephalans originated in the Silurian about 420 Ma, having survived from the end-Permian (250 Ma) mass extinction and undergoing familial diversifications during

  1. The social evolution of genocide across time and geographic space: Perspectives from evolutionary game theory

    OpenAIRE

    Anderton, Charles H.

    2015-01-01

    A standard evolutionary game theory model is used to reveal the interpersonal and geographic characteristics of a population that make it vulnerable to accepting the genocidal aims of political leaders. Under conditions identified in the space-less version of the model, genocide architects can engineer the social metamorphosis of a peaceful people-group into one that supports, or does not resist, the architects’ atrocity goals. The model reveals policy interventions that prevent the social ev...

  2. EU competition policy, vertical restraints, and innovation: an analysis from an evolutionary perspective

    OpenAIRE

    Kerber, Wolfgang; Vezzoso, Simonetta

    2004-01-01

    The EU competition policy in regard to vertical restraints is mainly based upon neoclassical efficiency-oriented reasonings, leading to a neglect of the innovation dimension. This paper analyses to what extent evolutionary theories of competition and innovation economics can be used to derive additional, new criteria for the assessment of vertical restraints. It is shown that Neo- Schumpeterian and Hayekian approaches to competition and innovation economics as well as knowledge-based theories...

  3. Role of Body Fat and Body Shape on Judgment of Female Health and Attractiveness: An Evolutionary Perspective

    Directory of Open Access Journals (Sweden)

    Devendra Singh

    2006-12-01

    Full Text Available The main aim of this paper is to present an evolutionary perspective for why women’s attractiveness is assigned a great importance in practically all human societies. We present the data that the woman’s body shape, or hourglass figure as defined by the size of waist-to-hip-ratio (WHR, reliably conveys information about a woman’s age, fertility, and health and that systematic variation in women’s WHR invokes systematic changes in attractiveness judgment by participants both in Western and non-Western societies. We also present evidence that attractiveness judgments based on the size of WHR are not artifact of body weight reduction. Then we present cross-cultural and historical data which attest to the universal appeal of WHR. We conclude that the current trend of describing attractiveness solely on the basis of body weight presents an incomplete, and perhaps inaccurate, picture of women’s attractiveness.

  4. Why do we all want to be young and beautiful (and women especially)? From the evolutionary psychological perspective.

    Science.gov (United States)

    Tadinac, Meri

    2010-12-01

    Within social sciences, the standards of beauty were for a long time considered to be culturally determined, meaning that different people with different life experiences in different cultures acquire different standards of beauty, as captured in the famous sentence "Beauty is in the eye of the beholder". However, two groups of findings have challenged this common assumption: first, people in different cultures generally agree on which faces are attractive; second, preferences emerge early in life, before cultural standards of beauty are likely to be assimilated. Evolutionary psychology explores the psychological adaptations (evolved psychological mechanisms constructed by natural selection) that constitute human nature. From the perspective of evolutionary psychology, beauty is not a cultural construct and appreciating beauty is not learned but is rather a biological adaptation, a part of universal human nature: the preferences for some physical characteristics reflect adaptations for mate choice because they signal aspects of mate quality. Theory of natural selection explains the adaptations, which help organisms in their tasks of survival. However, an organism can be adapted and survive for many years without passing its qualities to future generations--to pass them it must reproduce. The theory of sexual selection explains the adaptations that have arisen as a consequence of successful mating. In order to gain reproductive success, women and men adopt certain mate selection strategies--integrated sets of adaptations, not necessarily conscious, which organize and guide the individual's reproductive efforts. PMID:21830463

  5. Evolution of anterior Hox regulatory elements among chordates

    Directory of Open Access Journals (Sweden)

    Natale Alfonso

    2011-11-01

    Full Text Available Abstract Background The Hox family of transcription factors has a fundamental role in segmentation pathways and axial patterning of embryonic development and their clustered organization is linked with the regulatory mechanisms governing their coordinated expression along embryonic axes. Among chordates, of particular interest are the Hox paralogous genes in groups 1-4 since their expression is coupled to the control of regional identity in the anterior nervous system, where the highest structural diversity is observed. Results To investigate the degree of conservation in cis-regulatory components that form the basis of Hox expression in the anterior nervous system, we have used assays for transcriptional activity in ascidians and vertebrates to compare and contrast regulatory potential. We identified four regulatory sequences located near the CiHox1, CiHox2 and CiHox4 genes of the ascidian Ciona intestinalis which direct neural specific domains of expression. Using functional assays in Ciona and vertebrate embryos in combination with sequence analyses of enhancer fragments located in similar positions adjacent to Hox paralogy group genes, we compared the activity of these four Ciona cis-elements with a series of neural specific enhancers from the amphioxus Hox1-3 genes and from mouse Hox paralogous groups 1-4. Conclusions This analysis revealed that Kreisler and Krox20 dependent enhancers critical in segmental regulation of the hindbrain appear to be specific for the vertebrate lineage. In contrast, neural enhancers that function as Hox response elements through the action of Hox/Pbx binding motifs have been conserved during chordate evolution. The functional assays reveal that these Hox response cis-elements are recognized by the regulatory components of different and extant species. Together, our results indicate that during chordate evolution, cis-elements dependent upon Hox/Pbx regulatory complexes, are responsible for key aspects of

  6. Ciona as a Simple Chordate Model for Heart Development and Regeneration

    Directory of Open Access Journals (Sweden)

    Heather Evans Anderson

    2016-08-01

    Full Text Available Cardiac cell specification and the genetic determinants that govern this process are highly conserved among Chordates. Recent studies have established the importance of evolutionarily-conserved mechanisms in the study of congenital heart defects and disease, as well as cardiac regeneration. As a basal Chordate, the Ciona model system presents a simple scaffold that recapitulates the basic blueprint of cardiac development in Chordates. Here we will focus on the development and cellular structure of the heart of the ascidian Ciona as compared to other Chordates, principally vertebrates. Comparison of the Ciona model system to heart development in other Chordates presents great potential for dissecting the genetic mechanisms that underlie congenital heart defects and disease at the cellular level and might provide additional insight into potential pathways for therapeutic cardiac regeneration.

  7. Facts and fancies about early fossil chordates and vertebrates.

    Science.gov (United States)

    Janvier, Philippe

    2015-04-23

    The interrelationships between major living vertebrate, and even chordate, groups are now reasonably well resolved thanks to a large amount of generally congruent data derived from molecular sequences, anatomy and physiology. But fossils provide unexpected combinations of characters that help us to understand how the anatomy of modern groups was progressively shaped over millions of years. The dawn of vertebrates is documented by fossils that are preserved as either soft-tissue imprints, or minute skeletal fragments, and it is sometimes difficult for palaeontologists to tell which of them are reliable vertebrate remains and which merely reflect our idea of an ancestral vertebrate.

  8. Amphioxus: a peaceful anchovy fillet to illuminate Chordate Evolution (II)

    OpenAIRE

    Jordi Garcia-Fernàndez

    2006-01-01

    The genome of the amphioxus is on the horizon. With Linda Holland and Jeremy Gibson-Brown at the forefront, with all the amphioxus community behind, and with the Joint Genome Institute, the amphioxus genome will see the light this year, 2006. Hope that it will reflect the “prototypical” preduplicative genome of vertebrates. It may answer definitively what the human genome did not: Are we vertebrates octaploid? Will it shed light on the novelties that helped non-chordates to be cho...

  9. Fisherian and Wrightian perspectives in evolutionary genetics and model-mediated imposition of theoretical assumptions.

    Science.gov (United States)

    Winther, Rasmus Grønfeldt

    2006-05-21

    I investigate how theoretical assumptions, pertinent to different perspectives and operative during the modeling process, are central in determining how nature is actually taken to be. I explore two different models by Michael Turelli and Steve Frank of the evolution of parasite-mediated cytoplasmic incompatility, guided, respectively, by Fisherian and Wrightian perspectives. Since the two models can be shown to be commensurable both with respect to mathematics and data, I argue that the differences between them in the (1) mathematical presentation of the models, (2) explanations, and (3) objectified ontologies stem neither from differences in mathematical method nor the employed data, but from differences in the theoretical assumptions, especially regarding ontology, already present in the respective perspectives. I use my "set up, mathematically manipulate, explain, and objectify" (SMEO) account of the modeling process to track the model-mediated imposition of theoretical assumptions. I conclude with a discussion of the general implications of my analysis of these models for the controversy between Fisherian and Wrightian perspectives. PMID:16263132

  10. The Ontogenesis of Social Dominance: A Strategy-Based Evolutionary Perspective.

    Science.gov (United States)

    Hawley, Patricia H.

    1999-01-01

    Reintroduces the ethological concept of social dominance, and interprets it from a strategy-based perspective. Maintains that, by adopting this approach to social dominance and explicitly incorporating developmental processes and uniquely human capacities, human social-dominance patterns appear to be more similar to primate patterns than commonly…

  11. An evolutionary perspective of AMPK-TOR signaling in the three domains of life.

    Science.gov (United States)

    Roustan, Valentin; Jain, Arpit; Teige, Markus; Ebersberger, Ingo; Weckwerth, Wolfram

    2016-06-01

    AMPK and TOR protein kinases are the major control points of energy signaling in eukaryotic cells and organisms. They form the core of a complex regulatory network to co-ordinate metabolic activities in the cytosol with those in the mitochondria and plastids. Despite its relevance, it is still unclear when and how this regulatory pathway was formed during evolution, and to what extent its representations in the major eukaryotic lineages resemble each other. Here we have traced 153 essential proteins forming the human AMPK-TOR pathways across 412 species representing all three domains of life-prokaryotes (bacteria, archaea) and eukaryotes-and reconstructed their evolutionary history. The resulting phylogenetic profiles indicate the presence of primordial core pathways including seven proto-kinases in the last eukaryotic common ancestor. The evolutionary origins of the oldest components of the AMPK pathway, however, extend into the pre-eukaryotic era, and descendants of these ancient proteins can still be found in contemporary prokaryotes. The TOR complex in turn appears as a eukaryotic invention, possibly to aid in retrograde signaling between the mitochondria and the remainder of the cell. Within the eukaryotes, AMPK/TOR showed both a highly conserved core structure and a considerable plasticity. Most notably, KING1, a protein originally assigned as the γ subunit of AMPK in plants, is more closely related to the yeast SDS23 gene family than to the γ subunits in animals or fungi. This suggests its functional difference from a canonical AMPK γ subunit. PMID:27270999

  12. An evolutionary perspective of AMPK-TOR signaling in the three domains of life.

    Science.gov (United States)

    Roustan, Valentin; Jain, Arpit; Teige, Markus; Ebersberger, Ingo; Weckwerth, Wolfram

    2016-06-01

    AMPK and TOR protein kinases are the major control points of energy signaling in eukaryotic cells and organisms. They form the core of a complex regulatory network to co-ordinate metabolic activities in the cytosol with those in the mitochondria and plastids. Despite its relevance, it is still unclear when and how this regulatory pathway was formed during evolution, and to what extent its representations in the major eukaryotic lineages resemble each other. Here we have traced 153 essential proteins forming the human AMPK-TOR pathways across 412 species representing all three domains of life-prokaryotes (bacteria, archaea) and eukaryotes-and reconstructed their evolutionary history. The resulting phylogenetic profiles indicate the presence of primordial core pathways including seven proto-kinases in the last eukaryotic common ancestor. The evolutionary origins of the oldest components of the AMPK pathway, however, extend into the pre-eukaryotic era, and descendants of these ancient proteins can still be found in contemporary prokaryotes. The TOR complex in turn appears as a eukaryotic invention, possibly to aid in retrograde signaling between the mitochondria and the remainder of the cell. Within the eukaryotes, AMPK/TOR showed both a highly conserved core structure and a considerable plasticity. Most notably, KING1, a protein originally assigned as the γ subunit of AMPK in plants, is more closely related to the yeast SDS23 gene family than to the γ subunits in animals or fungi. This suggests its functional difference from a canonical AMPK γ subunit.

  13. Metaphylogeny of 82 gene families sheds a new light on chordate evolution

    Directory of Open Access Journals (Sweden)

    2006-04-01

    Full Text Available Achieving a better comprehension of the evolution of species has always been an important matter for evolutionary biologists. The deuterostome phylogeny has been described for many years, and three phyla are distinguishable: Echinodermata (including sea stars, sea urchins, etc…, Hemichordata (including acorn worms and pterobranchs, and Chordata (including urochordates, cephalochordates and extant vertebrates. Inside the Chordata phylum, the position of vertebrate species is quite unanimously accepted. Nonetheless, the position of urochordates in regard with vertebrates is still the subject of debate, and has even been suggested by some authors to be a separate phylum from cephalochordates and vertebrates. It was also the case for agnathans species –myxines and hagfish– for which phylogenetic evidence was recently given for a controversial monophyly. This raises the following question: which one of the cephalochordata or urochordata is the sister group of vertebrates and what are their relationships? In the present work, we analyzed 82 protein families presenting homologs between urochordata and other deuterostomes and focused on two points: 1 testing accurately the position of urochordata and cephalochordata phyla in regard with vertebrates as well as chordates monophyly, 2 performing an estimation of the rate of gene loss in the Ciona intestinalis genome. We showed that the urochordate phyla is the vertebrate sister group and that gene loss played a major role in structuring the urochordate genome.

  14. A tree of geese: A phylogenomic perspective on the evolutionary history of True Geese.

    Science.gov (United States)

    Ottenburghs, Jente; Megens, Hendrik-Jan; Kraus, Robert H S; Madsen, Ole; van Hooft, Pim; van Wieren, Sipke E; Crooijmans, Richard P M A; Ydenberg, Ronald C; Groenen, Martien A M; Prins, Herbert H T

    2016-08-01

    Phylogenetic incongruence can be caused by analytical shortcomings or can be the result of biological processes, such as hybridization, incomplete lineage sorting and gene duplication. Differentiation between these causes of incongruence is essential to unravel complex speciation and diversification events. The phylogeny of the True Geese (tribe Anserini, Anatidae, Anseriformes) was, until now, contentious, i.e., the phylogenetic relationships and the timing of divergence between the different goose species could not be fully resolved. We sequenced nineteen goose genomes (representing seventeen species of which three subspecies of the Brent Goose, Branta bernicla) and used an exon-based phylogenomic approach (41,736 exons, representing 5887 genes) to unravel the evolutionary history of this bird group. We thereby provide general guidance on the combination of whole genome evolutionary analyses and analytical tools for such cases where previous attempts to resolve the phylogenetic history of several taxa could not be unravelled. Identical topologies were obtained using either a concatenation (based upon an alignment of 6,630,626 base pairs) or a coalescent-based consensus method. Two major lineages, corresponding to the genera Anser and Branta, were strongly supported. Within the Branta lineage, the White-cheeked Geese form a well-supported sub-lineage that is sister to the Red-breasted Goose (Branta ruficollis). In addition, two main clades of Anser species could be identified, the White Geese and the Grey Geese. The results from the consensus method suggest that the diversification of the genus Anser is heavily influenced by rapid speciation and by hybridization, which may explain the failure of previous studies to resolve the phylogenetic relationships within this genus. The majority of speciation events took place in the late Pliocene and early Pleistocene (between 4 and 2millionyears ago), conceivably driven by a global cooling trend that led to the

  15. Structural Perspectives on the Evolutionary Expansion of Unique Protein-Protein Binding Sites.

    Science.gov (United States)

    Goncearenco, Alexander; Shaytan, Alexey K; Shoemaker, Benjamin A; Panchenko, Anna R

    2015-09-15

    Structures of protein complexes provide atomistic insights into protein interactions. Human proteins represent a quarter of all structures in the Protein Data Bank; however, available protein complexes cover less than 10% of the human proteome. Although it is theoretically possible to infer interactions in human proteins based on structures of homologous protein complexes, it is still unclear to what extent protein interactions and binding sites are conserved, and whether protein complexes from remotely related species can be used to infer interactions and binding sites. We considered biological units of protein complexes and clustered protein-protein binding sites into similarity groups based on their structure and sequence, which allowed us to identify unique binding sites. We showed that the growth rate of the number of unique binding sites in the Protein Data Bank was much slower than the growth rate of the number of structural complexes. Next, we investigated the evolutionary roots of unique binding sites and identified the major phyletic branches with the largest expansion in the number of novel binding sites. We found that many binding sites could be traced to the universal common ancestor of all cellular organisms, whereas relatively few binding sites emerged at the major evolutionary branching points. We analyzed the physicochemical properties of unique binding sites and found that the most ancient sites were the largest in size, involved many salt bridges, and were the most compact and least planar. In contrast, binding sites that appeared more recently in the evolution of eukaryotes were characterized by a larger fraction of polar and aromatic residues, and were less compact and more planar, possibly due to their more transient nature and roles in signaling processes.

  16. An evolutionary perspective on reproductive individual heterogeneity in a marine vertebrate.

    Science.gov (United States)

    Chambert, Thierry; Rotella, Jay J; Garrott, Robert A

    2014-09-01

    Although the quantification of individual heterogeneity in wild populations' vital rates has recently attracted growing interest among ecologists, the investigation of its evolutionary consequences remains limited, mainly because of the difficulties in assessing fitness and heritability from field studies on free-ranging animals. In the presence of individual variability, evaluation of fitness consequences can notably be complicated by the existence of trade-offs among different vital rates. In this study, to further assess the evolutionary significance of previously quantified levels of individual heterogeneity in female Weddell seal (Leptonychotes weddellii Lesson) reproductive rates (Chambert et al. ), we investigated how several life-history characteristics of female offspring were related to their mother's reproductive rate, as well as to other maternal traits (age and experience) and environmental conditions at birth. The probability and age of first reproduction (recruitment) of female offspring was not related to their mother's reproductive rate, suggesting the absence of a maternal trade-off between the number and quality of offspring a female produces. Evidence of a positive, but relatively weak, relationship between the reproductive rates of a mother and her female offspring was found, suggesting some degree of heritability in this trait. Using a simulation approach based on these statistical findings, we showed that substantial differences in the number of grandchildren, produced through female progeny, can be expected among females with different reproductive rates. Despite the presence of substantial stochastic variability, due to environmental fluctuations and other unidentified mechanisms, and in the light of the fact that the metrics obtained do not provide a full measure of real fitness, our results do suggest that the individual reproductive variability found in female Weddell seals could potentially have important fitness consequences.

  17. Altruism, egoism, or neither: A cognitive-efficiency-based evolutionary biological perspective on helping behavior.

    Science.gov (United States)

    Schulz, Armin W

    2016-04-01

    I argue for differences in the cognitive efficiency of different psychologies underlying helping behavior, and present an account of the adaptive pressures that result from these differences. Specifically, I argue that organisms often face pressure to move away from only being egoistically motivated to help: non-egoistic organisms are often able to determine how to help other organisms more quickly and with less recourse to costly cognitive resources like concentration and attention. Furthermore, I also argue that, while these pressures away from pure egoism can lead to the evolution of altruists, they can also lead to the evolution of reciprocation-focused behaviorist helpers or even of reflex-driven helpers (who are neither altruists nor egoists). In this way, I seek to broaden the set of considerations typically taken into account when assessing the evolution of the psychology of helping behavior-which tend to be restricted to matters of reliability-and also try to make clearer the role of evolutionary biological considerations in the discussion of this apparently straightforwardly psychological phenomenon.

  18. Stem cells and lineages of the intestine: a developmental and evolutionary perspective.

    Science.gov (United States)

    Takashima, Shigeo; Gold, David; Hartenstein, Volker

    2013-03-01

    The intestine consists of epithelial cells that secrete digestive enzymes and mucus (gland cells), absorb food particles (enterocytes), and produce hormones (endocrine cells). Intestinal cells are rapidly turned over and need to be replaced. In cnidarians, mitosis of differentiated intestinal cells accounts for much of the replacement; in addition, migratory, multipotent stem cells (interstitial cells) contribute to the production of intestinal cells. In other phyla, intestinal cell replacement is solely the function of stem cells entering the gut from the outside (such as in case of the neoblasts of platyhelminths) or intestinal stem cells located within the midgut epithelium (as in both vertebrates or arthropods). We will attempt in the following to review important aspects of midgut stem cells in different animal groups: where are they located, what types of lineages do they produce, and how do they develop. We will start out with a comparative survey of midgut cell types found across the animal kingdom; then briefly look at the specification of these cells during embryonic development; and finally focus on the stem cells that regenerate midgut cells during adult life. In a number of model systems, including mouse, zebrafish and Drosophila, the molecular pathways controlling intestinal stem cells proliferation and the specification of intestinal cell types are under intensive investigation. We will highlight findings of the recent literature, focusing on aspects that are shared between the different models and that point at evolutionary ancient mechanisms of intestinal cell formation. PMID:23179635

  19. Structure and scale of the mechanics of mammalian dental enamel viewed from an evolutionary perspective.

    Science.gov (United States)

    Lucas, Peter W; Philip, Swapna M; Al-Qeoud, Dareen; Al-Draihim, Nuha; Saji, Sreeja; van Casteren, Adam

    2016-01-01

    Mammalian enamel, the contact dental tissue, is something of an enigma. It is almost entirely made of hydroxyapatite, yet exhibits very different mechanical behavior to a homogeneous block of the same mineral. Recent approaches suggest that its hierarchical composite form, similar to other biological hard tissues, leads to a mechanical performance that depends very much on the scale of measurement. The stiffness of the material is predicted to be highest at the nanoscale, being sacrificed to produce a high toughness at the largest scale, that is, at the level of the tooth crown itself. Yet because virtually all this research has been conducted only on human (or sometimes "bovine") enamel, there has been little regard for structural variation of the tissue considered as evolutionary adaptation to diet. What is mammalian enamel optimized for? We suggest that there are competing selective pressures. We suggest that the structural characteristics that optimize enamel to resist large-scale fractures, such as crown failures, are very different to those that resist wear (small-scale fracture). While enamel is always designed for damage tolerance, this may be suboptimal in the enamel of some species, including modern humans (which have been the target of most investigations), in order to counteract wear. The experimental part of this study introduces novel techniques that help to assess resistance at the nanoscale.

  20. Incorporating an ontogenetic perspective into evolutionary theory of sexual size dimorphism.

    Science.gov (United States)

    Chou, Chun-Chia; Iwasa, Yoh; Nakazawa, Takefumi

    2016-02-01

    Sexual size dimorphism (SSD) describes divergent body sizes of adult males and females. While SSD has traditionally been explained by sexual and fecundity selection, recent advances in physiology and developmental biology emphasize that SSD would occur proximately because of sexual differences in ontogenetic growth trajectories (i.e., growth rate and duration). Notably, these ontogenetic traits are subject to energetic or time constraints and thus traded off with fitness components (e.g., survival and reproduction). To elucidate the importance of such ontogenetic trade-offs in the evolution of SSD, we developed a new theoretical framework by extending quantitative genetic models for the evolution of sexual dimorphism in which we reinterpret the trait as body size and reformulate sex-specific fitness in size-dependent manners. More specifically, we assume that higher growth rate or longer growth duration leads to larger body size and higher reproductive success but incurs the cost of lower survivorship or shorter reproduction period. We illustrate how two sexes would optimize ontogenetic growth trajectories in sex-specific ways and exhibit divergent body sizes. The present framework provides new insights into the evolutionary theory of SSD and predictions for empirical testing. PMID:26768067

  1. What can other animals tell us about human social cognition? An evolutionary perspective on reflective and reflexive processing.

    Science.gov (United States)

    Hecht, E E; Patterson, R; Barbey, A K

    2012-01-01

    Human neuroscience has seen a recent boom in studies on reflective, controlled, explicit social cognitive functions like imitation, perspective-taking, and empathy. The relationship of these higher-level functions to lower-level, reflexive, automatic, implicit functions is an area of current research. As the field continues to address this relationship, we suggest that an evolutionary, comparative approach will be useful, even essential. There is a large body of research on reflexive, automatic, implicit processes in animals. A growing perspective sees social cognitive processes as phylogenically continuous, making findings in other species relevant for understanding our own. One of these phylogenically continuous processes appears to be self-other matching or simulation. Mice are more sensitive to pain after watching other mice experience pain; geese experience heart rate increases when seeing their mate in conflict; and infant macaques, chimpanzees, and humans automatically mimic adult facial expressions. In this article, we review findings in different species that illustrate how such reflexive processes are related to ("higher order") reflexive processes, such as cognitive empathy, theory of mind, and learning by imitation. We do so in the context of self-other matching in three different domains-in the motor domain (somatomotor movements), in the perceptual domain (eye movements and cognition about visual perception), and in the autonomic/emotional domain. We also review research on the developmental origin of these processes and their neural bases across species. We highlight gaps in existing knowledge and point out some questions for future research. We conclude that our understanding of the psychological and neural mechanisms of self-other mapping and other functions in our own species can be informed by considering the layered complexity these functions in other species. PMID:22866032

  2. Evolutionary and functional perspectives on signaling from neuronal surface to nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, Samuel M.; Li, Boxing; Tsien, Richard W., E-mail: richard.tsien@nyumc.org; Ma, Huan, E-mail: mahuan@gmail.com

    2015-04-24

    Reliance on Ca{sup 2+} signaling has been well-preserved through the course of evolution. While the complexity of Ca{sup 2+} signaling pathways has increased, activation of transcription factors including CREB by Ca{sup 2+}/CaM-dependent kinases (CaMKs) has remained critical for long-term plasticity. In C. elegans, the CaMK family is made up of only three members, and CREB phosphorylation is mediated by CMK-1, the homologue of CaMKI. CMK-1 nuclear translocation directly regulates adaptation of thermotaxis behavior in response to changes in the environment. In mammals, the CaMK family has been expanded from three to ten members, enabling specialization of individual elements of a signal transduction pathway and increased reliance on the CaMKII subfamily. This increased complexity enables private line communication between Ca{sup 2+} sources at the cell surface and specific cellular targets. Using both new and previously published data, we review the mechanism of a γCaMKII-CaM nuclear translocation. This intricate pathway depends on a specific role for multiple Ca{sup 2+}/CaM-dependent kinases and phosphatases: α/βCaMKII phosphorylates γCaMKII to trap CaM; CaN dephosphorylates γCaMKII to dispatch it to the nucleus; and PP2A induces CaM release from γCaMKII so that CaMKK and CaMKIV can trigger CREB phosphorylation. Thus, while certain basic elements have been conserved from C. elegans, evolutionary modifications offer opportunities for targeted communication, regulation of key nodes and checkpoints, and greater specificity and flexibility in signaling.

  3. Brain mechanisms of acoustic communication in humans and nonhuman primates: an evolutionary perspective.

    Science.gov (United States)

    Ackermann, Hermann; Hage, Steffen R; Ziegler, Wolfram

    2014-12-01

    Any account of "what is special about the human brain" (Passingham 2008) must specify the neural basis of our unique ability to produce speech and delineate how these remarkable motor capabilities could have emerged in our hominin ancestors. Clinical data suggest that the basal ganglia provide a platform for the integration of primate-general mechanisms of acoustic communication with the faculty of articulate speech in humans. Furthermore, neurobiological and paleoanthropological data point at a two-stage model of the phylogenetic evolution of this crucial prerequisite of spoken language: (i) monosynaptic refinement of the projections of motor cortex to the brainstem nuclei that steer laryngeal muscles, presumably, as part of a "phylogenetic trend" associated with increasing brain size during hominin evolution; (ii) subsequent vocal-laryngeal elaboration of cortico-basal ganglia circuitries, driven by human-specific FOXP2 mutations.;>This concept implies vocal continuity of spoken language evolution at the motor level, elucidating the deep entrenchment of articulate speech into a "nonverbal matrix" (Ingold 1994), which is not accounted for by gestural-origin theories. Moreover, it provides a solution to the question for the adaptive value of the "first word" (Bickerton 2009) since even the earliest and most simple verbal utterances must have increased the versatility of vocal displays afforded by the preceding elaboration of monosynaptic corticobulbar tracts, giving rise to enhanced social cooperation and prestige. At the ontogenetic level, the proposed model assumes age-dependent interactions between the basal ganglia and their cortical targets, similar to vocal learning in some songbirds. In this view, the emergence of articulate speech builds on the "renaissance" of an ancient organizational principle and, hence, may represent an example of "evolutionary tinkering" (Jacob 1977). PMID:24827156

  4. The effect of stochasticity on the lac operon: an evolutionary perspective.

    Directory of Open Access Journals (Sweden)

    Milan van Hoek

    2007-06-01

    Full Text Available The role of stochasticity on gene expression is widely discussed. Both potential advantages and disadvantages have been revealed. In some systems, noise in gene expression has been quantified, in among others the lac operon of Escherichia coli. Whether stochastic gene expression in this system is detrimental or beneficial for the cells is, however, still unclear. We are interested in the effects of stochasticity from an evolutionary point of view. We study this question in the lac operon, taking a computational approach: using a detailed, quantitative, spatial model, we evolve through a mutation-selection process the shape of the promoter function and therewith the effective amount of stochasticity. We find that noise values for lactose, the natural inducer, are much lower than for artificial, nonmetabolizable inducers, because these artificial inducers experience a stronger positive feedback. In the evolved promoter functions, noise due to stochasticity in gene expression, when induced by lactose, only plays a very minor role in short-term physiological adaptation, because other sources of population heterogeneity dominate. Finally, promoter functions evolved in the stochastic model evolve to higher repressed transcription rates than those evolved in a deterministic version of the model. This causes these promoter functions to experience less stochasticity in gene expression. We show that a high repression rate and hence high stochasticity increases the delay in lactose uptake in a variable environment. We conclude that the lac operon evolved such that the impact of stochastic gene expression is minor in its natural environment, but happens to respond with much stronger stochasticity when confronted with artificial inducers. In this particular system, we have shown that stochasticity is detrimental. Moreover, we demonstrate that in silico evolution in a quantitative model, by mutating the parameters of interest, is a promising way to unravel

  5. Origins of anteroposterior patterning and Hox gene regulation during chordate evolution.

    OpenAIRE

    Schilling, T. F.; Knight, R D

    2001-01-01

    All chordates share a basic body plan and many common features of early development. Anteroposterior (AP) regions of the vertebrate neural tube are specified by a combinatorial pattern of Hox gene expression that is conserved in urochordates and cephalochordates. Another primitive feature of Hox gene regulation in all chordates is a sensitivity to retinoic acid during embryogenesis, and recent developmental genetic studies have demonstrated the essential role for retinoid signalling in verteb...

  6. Characterization of an individual neural crest-like cell lineage in the invertebrate chordate Ciona intestinalis

    OpenAIRE

    Cone, Angela C.

    2008-01-01

    During embryogenesis, all chordate embryos undergo neurulation to form a dorsal, hollow nerve cord. Neural crest cells (NCC), considered a vertebrate innovation, arise during neurulation and later differentiate into a multitude of tissues that account for much of the structural complexity that distinguishes craniates from invertebrate chordates [1, 2]. NCCs are induced and specified at the border of the neural and non-neural ectoderm by a complex network of inductive signals and transcription...

  7. How the unique configuration of the human head may enhance flavor perception capabilities: an evolutionary perspective

    Directory of Open Access Journals (Sweden)

    Daniel E Lieberman

    2014-07-01

    configuration of the human pharynx (Figure 1. Unlike other mammals, humans have a relatively short and retracted face, which results in a short oral cavity with a rounded tongue whose inferior margin lies well below the margin of the mandible. Because the hyoid and larynx are suspended from the base of the tongue, the human larynx becomes separated early in postnatal life relative to the oral cavity, causing humans to be the only species with a non-intranarial epiglottis in which the epiglottis does not contact the soft palate [3]. As a result, humans have no separation between the airway and foodway in the oropharynx. The non-intranarial epiglottis makes humans more likely to choke on food than other mammals, but helps humans produce more perceptible speech by setting up a two-tube vocal tract whose horizontal and vertical portions are equal in length and whose cross sectional areas can be modified independently by approximately 10-fold by the tongue [5]. Although this configuration almost certainly evolved for speech, it likely has beneficial consequences for retronasal olfaction. Whereas all other mammals, including chimpanzees, store a bolus of food prior to swallowing anterior to the epiglottis and thus removed from the airway, humans must store the bolus superior to the epiglottis in the pathway of expired air. Thus as humans breathe while chewing between swallows, expired air may be more likely to pick up volatile compounds from foods, which are then transported retronasally to the olfactory epithelium. The hypothesis that derived features of the human head and neck enhance retronasal olfaction needs to be tested. Comparative data are especially needed on retronasal airflow in a variety of mammals including other primates. In addition, more data are needed on retronasal olfactory perception in great apes such as chimpanzees. However, if true, then it is possible that humans may have uniquely enhanced abilities to detect flavor from food, raising several evolutionary

  8. Evolutionary mitogenomics of Chordata: the strange case of ascidians and vertebrates

    Directory of Open Access Journals (Sweden)

    C Gissi

    2009-03-01

    Full Text Available The availability of almost one thousand complete mitochondrial genome (mtDNA sequences of chordates provides an almost unique opportunity to analyse the evolution of this genome in the phylum Chordata, and to identify possible divergent evolutionary trends followed by the three chordate subphyla: Vertebrata, Cephalochordata and Tunicata.Here, we review some genome-level features of mtDNA, such as genetic code, gene content, genome architecture and gene strand asymmetry, mostly focusing on differences existing between tunicates and remaining chordates. Indeed, tunicate mtDNAs show a surprisingly high variability in several genome-level features, even though the current tunicate taxon sampling is absolutely insufficient and is focused mainly on the class Ascidiacea. On the contrary, a stabilization of the mtDNA structural and evolutionary features is observed in both cephalochordates and vertebrates, where genome-level features are almost invariant. Thus, different evolutionary dynamics, probably related to divergent functional constraints, have modelled the overall mtDNA structure and organization of the three chordate subphyla.

  9. The genome sequence of the colonial chordate, Botryllus schlosseri

    Science.gov (United States)

    Voskoboynik, Ayelet; Neff, Norma F; Sahoo, Debashis; Newman, Aaron M; Pushkarev, Dmitry; Koh, Winston; Passarelli, Benedetto; Fan, H Christina; Mantalas, Gary L; Palmeri, Karla J; Ishizuka, Katherine J; Gissi, Carmela; Griggio, Francesca; Ben-Shlomo, Rachel; Corey, Daniel M; Penland, Lolita; White, Richard A; Weissman, Irving L; Quake, Stephen R

    2013-01-01

    Botryllus schlosseri is a colonial urochordate that follows the chordate plan of development following sexual reproduction, but invokes a stem cell-mediated budding program during subsequent rounds of asexual reproduction. As urochordates are considered to be the closest living invertebrate relatives of vertebrates, they are ideal subjects for whole genome sequence analyses. Using a novel method for high-throughput sequencing of eukaryotic genomes, we sequenced and assembled 580 Mbp of the B. schlosseri genome. The genome assembly is comprised of nearly 14,000 intron-containing predicted genes, and 13,500 intron-less predicted genes, 40% of which could be confidently parceled into 13 (of 16 haploid) chromosomes. A comparison of homologous genes between B. schlosseri and other diverse taxonomic groups revealed genomic events underlying the evolution of vertebrates and lymphoid-mediated immunity. The B. schlosseri genome is a community resource for studying alternative modes of reproduction, natural transplantation reactions, and stem cell-mediated regeneration. DOI: http://dx.doi.org/10.7554/eLife.00569.001 PMID:23840927

  10. Evolutionary Origin of GnIH and NPFF in Chordates: Insights from Novel Amphioxus RFamide Peptides

    OpenAIRE

    Tomohiro Osugi; Tomoki Okamura; You Lee Son; Makoto Ohkubo; Takayoshi Ubuka; Yasuhisa Henmi; Kazuyoshi Tsutsui

    2014-01-01

    Gonadotropin-inhibitory hormone (GnIH) is a newly identified hypothalamic neuropeptide that inhibits pituitary hormone secretion in vertebrates. GnIH has an LPXRFamide (X = L or Q) motif at the C-terminal in representative species of gnathostomes. On the other hand, neuropeptide FF (NPFF), a neuropeptide characterized as a pain-modulatory neuropeptide, in vertebrates has a PQRFamide motif similar to the C-terminal of GnIH, suggesting that GnIH and NPFF have diverged from a common ancestor. Be...

  11. Evolutionary functional elaboration of the Elovl2/5 gene family in chordates

    OpenAIRE

    Óscar Monroig; Mónica Lopes-Marques; Navarro, Juan C.; Francisco Hontoria; Raquel Ruivo; Miguel M. Santos; Byrappa Venkatesh; Tocher, Douglas R.; L Filipe C Castro

    2016-01-01

    The biosynthesis of long-chain polyunsaturated fatty acids (LC-PUFA) provides an intriguing example on how multi-enzymatic cascades evolve. Essential LC-PUFA, such as arachidonic, eicosapentaenoic, and docosahexaenoic acids (DHA), can be acquired from the diet but are also endogenously retailored from C18 precursors through consecutive elongations and desaturations catalyzed, respectively, by fatty acyl elongase and desaturase enzymes. The molecular wiring of this enzymatic pathway defines th...

  12. Evolutionary dynamics of olfactory receptor genes in chordates: interaction between environments and genomic contents

    OpenAIRE

    Niimura Yoshihito

    2009-01-01

    Abstract Olfaction is essential for the survival of animals. Versatile odour molecules in the environment are received by olfactory receptors (ORs), which form the largest multigene family in vertebrates. Identification of the entire repertories of OR genes using bioinformatics methods from the whole-genome sequences of diverse organisms revealed that the numbers of OR genes vary enormously, ranging from ~1,200 in rats and ~400 in humans to ~150 in zebrafish and ~15 in pufferfish. Most specie...

  13. Characterization of bbtTICAM from amphioxus suggests the emergence of a MyD88-independent pathway in basal chordates

    Institute of Scientific and Technical Information of China (English)

    ManyiYang; ShaochunYuan; Shengfeng Huang; Jun Li; Liqun Xu; Huiqing Huang; Xin Tao; Jian peng; Anlong Xu

    2011-01-01

    The MyD88-independent pathway,one of the two crucial TLR signaling routes,Is thought to be a vertebrate innovation.However,a novel Toll/interleukin-1 receptor (TIR) adaptor,designated bbtTICAM,which was identified in the basal chordate amphioxus,links this pathway to invertebrates.The protein architecture of bbtTICAM is similar to that of vertebrate TICAM1 (TIR-containing adaptor molecule-1,also known as TRIF),while phylogenetic analysis based on the TIR domain indicated that bbtTICAM is the oldest ortholog of vertebrate TICAMI and TICAM2(TIR-containing adaptor molecule-2,also known as TRAM).Similar to human TICAM1,bbtTICAM activates NF-κB in a MyD88-independent manner by interacting with receptor interacting protein (RIP) via its RHIM motif.Such activation requires bbtTICAM to form homodimers in endosomes,and it may be negatively regulated by amphioxus SARM (sterile a and armadillo motif-containing protein) and TRAF2.However,bbtTICAM did not induce the production of type I interferon.Thus,our study not only presents the ancestral features of vertebrate TICAM I and TICAM2,but also reveals the evolutionary origin of the MyD88-independent pathway from basal chordates,which will aid in understanding the development of the vertebrate TLR network.

  14. Prions: an evolutionary perspective.

    Science.gov (United States)

    Ogayar, A; Sánchez-Pérez, M

    1998-09-01

    Studies in both prion-due diseases in mammals and some non-Mendelian hereditary processes in yeasts have demonstrated that certain proteins are able to transmit structural information and self-replication. This induces the corresponding conformational changes in other proteins with identical or similar sequences. This ability of proteins may have been very useful during prebiotic chemical evolution, prior to the establishment of the genetic code. During this stage, proteins (proteinoids) must have molded and selected their structural folding units through direct interaction with the environment. The proteinoids that acquired the ability to propagate their conformations (which we refer to as conformons) would have acted as reservoirs and transmitters of a given structural information and hence could have acted as selectors for conformational changes. Despite the great advantage that arose from the establishment of the genetic code, the ability to propagate conformational changes did not necessarily disappear. Depending on the degree of involvement of this capacity in biological evolution, we propose two not mutually exclusive hypotheses: (i) extant prions could be an atavism of ancestral conformons, which would have co-evolved with cells, and (ii) the evolution of conformons would have produced cellular proteins, able to transmit structural information, and, in some cases, participating in certain processes of regulation and epigenesis. Therefore, prions could also be seen as conformons of a conventional infectious agent (or one that co-evolved with it independently) that, after a longer or shorter adaptive period, would have interacted with conformons from the host cells. PMID:10943358

  15. Marriage: an evolutionary perspective.

    Science.gov (United States)

    Weisfeld, Glenn E; Weisfeld, Carol C

    2002-12-01

    Marriage is universal, and pair bonding is found in other species too with highly dependent young. So marriage functions as a reproductive social arrangement that traditionally involved the extended family. The sexes are not identical in their biological contributions to children's survival, so they seek somewhat different attributes in a mate. Men seek a young, attractive, sexually faithful bride. Women seek a man who is older, taller, and (as in many other species) socially dominant. Both sexes prefer a kind, healthy, attractive, similar mate who is emotionally attached to them. A spouse who fails to maintain sufficiently high mate value is vulnerable to divorce. Infertility and sexual dissatisfaction predict divorce, as does death of a child, but the more children, the stabler the marriage. Cross-cultural data suggest that cruel or subdominant men (e.g., poor providers) and unfaithful women are prone to divorce. Marriages in which the wife dominates the husband in economic contributions, nonverbal behavior, and decision making tend to be less satisfying. In societies in which wives are economically independent of husbands, divorce rates are high. As women's economic power has risen with industrialization, divorce rates have climbed. Economic and fitness considerations also help explain cultural differences in polygyny, age at marriage, arranged marriage, concern with the bride's sexual chastity, and marriage ceremonies. Other factors also affect marital dynamics, such as state subsidies to families, the sex ratio, and influence of the couple's parents.

  16. Exercise and cognitive function: a hypothesis for the association of type II diabetes mellitus and Alzheimer's disease from an evolutionary perspective

    Directory of Open Access Journals (Sweden)

    Brito Gilberto NO

    2009-09-01

    Full Text Available Abstract The association of type II diabetes mellitus (DM2 with Alzheimer's disease (AD has received considerable attention in recent years. In the present paper, a hypothesis for this association from an evolutionary perspective, with emphasis on the close interplay between exercise and cognitive function, will be advanced in order to provide a biological rationale for the notion that the fundamental metabolic features of DM2 act in the brain over a protracted time span to induce the neuropathological characteristics of Alzheimer's disease thereby producing cognitive impairment. It is hoped that this hypothesis puts the association of DM2 and AD on firm conceptual grounds from a biological perspective and offers directions for further research.

  17. Evolution of a core gene network for skeletogenesis in chordates.

    Directory of Open Access Journals (Sweden)

    Jochen Hecht

    2008-03-01

    Full Text Available The skeleton is one of the most important features for the reconstruction of vertebrate phylogeny but few data are available to understand its molecular origin. In mammals the Runt genes are central regulators of skeletogenesis. Runx2 was shown to be essential for osteoblast differentiation, tooth development, and bone formation. Both Runx2 and Runx3 are essential for chondrocyte maturation. Furthermore, Runx2 directly regulates Indian hedgehog expression, a master coordinator of skeletal development. To clarify the correlation of Runt gene evolution and the emergence of cartilage and bone in vertebrates, we cloned the Runt genes from hagfish as representative of jawless fish (MgRunxA, MgRunxB and from dogfish as representative of jawed cartilaginous fish (ScRunx1-3. According to our phylogenetic reconstruction the stem species of chordates harboured a single Runt gene and thereafter Runt locus duplications occurred during early vertebrate evolution. All newly isolated Runt genes were expressed in cartilage according to quantitative PCR. In situ hybridisation confirmed high MgRunxA expression in hard cartilage of hagfish. In dogfish ScRunx2 and ScRunx3 were expressed in embryonal cartilage whereas all three Runt genes were detected in teeth and placoid scales. In cephalochordates (lancelets Runt, Hedgehog and SoxE were strongly expressed in the gill bars and expression of Runt and Hedgehog was found in endo- as well as ectodermal cells. Furthermore we demonstrate that the lancelet Runt protein binds to Runt binding sites in the lancelet Hedgehog promoter and regulates its activity. Together, these results suggest that Runt and Hedgehog were part of a core gene network for cartilage formation, which was already active in the gill bars of the common ancestor of cephalochordates and vertebrates and diversified after Runt duplications had occurred during vertebrate evolution. The similarities in expression patterns of Runt genes support the view

  18. Symmetry breaking and convergent extension in early chordate development.

    Science.gov (United States)

    Schiffmann, Yoram

    2006-10-01

    The initiation of axis, polarity, cell differentiation, and gastrulation in the very early chordate development is due to the breaking of radial symmetry. It is believed that this occurs by an external signal. We suggest instead spontaneous symmetry breaking through the agency of the Turing-Child field. Increased size or decreased diffusivity, both brought about by mitotic activity, cause the spontaneous loss of stability of the homogeneous state and the evolution of the metabolic pattern during development. The polar metabolic pattern is the cause of polar gene expression, polar morphogenesis (gastrulation), and polar mitotic activity. The Turing-Child theory explains not only the spontaneous formation of the invagination in gastrulation but also the coherent cell movement observed in convergence and extension during gastrulation and neurulation. The theory is demonstrated with respect to experimental observations on the early development of fish, amphibian, and the chick. The theory can explain a multitude of experimental details. For example, it explains the splayed polar progression of reduction in the fish blastoderm. Reduction starts on that side of the blastoderm margin, which will initiate invagination several hours later. It progresses toward the blastoderm center and somewhat laterally from this future "dorsal lip". This is precisely as predicted by a Turing-Child system in a circle. And for a fish like zebrafish with a blastoderm that is slightly oval, reduction is observed to progress along the long axis of the ellipse, which is what Turing-Child theory predicts. In general the shape and the chemical nature of the experimental patterns are the same as predicted by the Turing couple (cAMP, ATP). Embryological polarity and convergent extension are based on polar eigenfunction and saddle-shaped eigenfunction, respectively.

  19. Evolutionary relationships of Aurora kinases: Implications for model organism studies and the development of anti-cancer drugs

    Directory of Open Access Journals (Sweden)

    Patrick Denis R

    2004-10-01

    Full Text Available Abstract Background As key regulators of mitotic chromosome segregation, the Aurora family of serine/threonine kinases play an important role in cell division. Abnormalities in Aurora kinases have been strongly linked with cancer, which has lead to the recent development of new classes of anti-cancer drugs that specifically target the ATP-binding domain of these kinases. From an evolutionary perspective, the species distribution of the Aurora kinase family is complex. Mammals uniquely have three Aurora kinases, Aurora-A, Aurora-B, and Aurora-C, while for other metazoans, including the frog, fruitfly and nematode, only Aurora-A and Aurora-B kinases are known. The fungi have a single Aurora-like homolog. Based on the tacit assumption of orthology to human counterparts, model organism studies have been central to the functional characterization of Aurora kinases. However, the ortholog and paralog relationships of these kinases across various species have not been rigorously examined. Here, we present comprehensive evolutionary analyses of the Aurora kinase family. Results Phylogenetic trees suggest that all three vertebrate Auroras evolved from a single urochordate ancestor. Specifically, Aurora-A is an orthologous lineage in cold-blooded vertebrates and mammals, while structurally similar Aurora-B and Aurora-C evolved more recently in mammals from a duplication of an ancestral Aurora-B/C gene found in cold-blooded vertebrates. All so-called Aurora-A and Aurora-B kinases of non-chordates are ancestral to the clade of chordate Auroras and, therefore, are not strictly orthologous to vertebrate counterparts. Comparisons of human Aurora-B and Aurora-C sequences to the resolved 3D structure of human Aurora-A lends further support to the evolutionary scenario that vertebrate Aurora-B and Aurora-C are closely related paralogs. Of the 26 residues lining the ATP-binding active site, only three were variant and all were specific to Aurora-A. Conclusions In

  20. Quantitative genetics approaches to study evolutionary processes in ecotoxicology; a perspective from research on the evolution of resistance.

    Science.gov (United States)

    Klerks, Paul L; Xie, Lingtian; Levinton, Jeffrey S

    2011-05-01

    Quantitative genetic approaches are often used to study evolutionary processes in ecotoxicology. This paper focuses on the evolution of resistance to environmental contaminants-an important evolutionary process in ecotoxicology. Three approaches are commonly employed to study the evolution of resistance: (1) Assessing whether a contaminant-exposed population has an increased resistance relative to a control population, using either spatial or temporal comparisons. (2) Estimating a population's heritability of resistance. (3) Investigating responses in a laboratory selection experiment. All three approaches provide valuable information on the potential for contaminants to affect a population's evolutionary trajectory via natural selection. However, all three approaches have inherent limitations, including difficulty in separating the various genetic and environmental variance components, responses being dependent on specific population and testing conditions, and inability to fully capture natural conditions in the laboratory. In order to maximize insights into the long-term consequences of adaptation, it is important to not just look at resistance itself, but also at the fitness consequences and at correlated responses in characteristics other than resistance. The rapid development of molecular genetics has yielded alternatives to the "black box" approach of quantitative genetics, but the presence of different limitations and strengths in the two fields means that they should be viewed as complementary rather than exchangeable. Quantitative genetics is benefiting from the incorporation of molecular tools and remains an important field for studying evolutionary toxicology.

  1. Modeling RNA polymerase interaction in mitochondria of chordates

    Directory of Open Access Journals (Sweden)

    Lyubetsky Vassily A

    2012-08-01

    selected genes only relative RNA concentrations have been experimentally determined. Conversely, these characteristics and absolute transcription levels can be obtained using relative RNA concentrations and RNA half-lives known from various experimental studies. In this case, the “inverse problem” is solved with multi-objective optimization. Conclusions In this study, we demonstrate that our model accurately reproduces all relevant experimental data available for plant plastids, as well as the mitochondria of chordates. Using experimental data, the model is applied to estimate binding intensities of phage-type RNA polymerases to their promoters as well as predicting terminator characteristics, including polarization. In addition, one can predict characteristics of phage-type RNA polymerases and the transcription process that are difficult to measure directly, e.g., the association between the promoter’s nucleotide composition and the intensity of polymerase binding. To illustrate the application of our model in functional predictions, we propose a possible mechanism for MELAS syndrome development in human involving a decrease of Phe-tRNA, Val-tRNA and rRNA concentrations in the cell. In addition, we describe how changes in methylation patterns of the mTERF binding site and three promoters in hypothyroid rat correlate with changes in intensities of the mTERF binding and transcription initiations. Finally, we introduce an auxiliary model to describe the interaction between polysomal mRNA and ribonucleases.

  2. What can other animals tell us about human social cognition?An evolutionary perspective on reflective and reflexive processing

    OpenAIRE

    Hecht, Erin E.; Richard ePatterson; Barbey, Aron K.

    2012-01-01

    Human neuroscience has seen a recent boom in studies on reflective, controlled, explicit social cognitive functions like imitation, perspective‐taking, and empathy. The relationship of these higher‐level functions to lower‐level, reflexive, automatic, implicit functions is an area of current research. As the field continues to address this relationship, we suggest that an evolutionary, comparative approach will be useful, even essential. There is a large body of research on reflexive, automat...

  3. Endogenous growth and environmental policy: are the processes of growth and tertiarisation in developed economies reversible? An evolutionary perspective

    OpenAIRE

    Desmarchelier, Benoît; Gallouj, FaÏz

    2010-01-01

    The starting point for this article is the idea put forward by Gadrey (2008, 2010) that environmental problems and a policy of addressing them by introducing an environmental tax could trigger economic contraction and downscaling and a shrinking of the service sector in developed economies. The purpose of this article is to test these hypotheses using an evolutionary simulation model. To this end, we use a model of endogenous growth and structural change into which an environmental dimension ...

  4. The Social Evolution of Terror and Genocide across Time and Geographic Space: Perspectives from Evolutionary Game Theory

    OpenAIRE

    Charles Anderton

    2014-01-01

    This article uses evolutionary game theory to reveal the interpersonal and geographic characteristics of a society that make it vulnerable to a conquest from within by terrorist organizations and genocide architects. Under conditions identified in the space-less version of the model, entrepreneurs of violence can create the social metamorphosis of a peaceful people group into one that supports or does not resist violence against an out-group. The model is extended into geographic space by ana...

  5. Theorie und Empirie aus evolutionsökonomischer Sicht Theory and Empirical Facts in the Perspective of Evolutionary Economics

    OpenAIRE

    Ulrich Fehl

    2004-01-01

    According to Colander, modern economics is economics of the model. Models have to be testable, in order to get a "theory with measurement". This procedure was recently criticized vehemently by Blaug maintaining that there is only little empirical progress in the economics of today. He makes the case for evolutionary economics because the latter is considering especially entrepreneurship and innovations, topics which are neglected by economists constructing and testing models. The reason for t...

  6. LA CONSERVACIÓN BIOLÓGICA Y SU PERSPECTIVA EVOLUTIVA Biological Conservation and its Evolutionary Perspective

    Directory of Open Access Journals (Sweden)

    OLGA L MONTENEGRO

    Full Text Available Este artículo revisa tres de las principales causas de amenaza a la diversidad biológica, como son la fragmentación y pérdida del hábitat, así como la invasión de especies exóticas, principalmente en lo que compete a sus implicaciones evolutivas. Los efectos de la fragmentación y/o pérdida del hábitat pueden revisarse a la luz de la sinergia entre factores demográficos y genéticos que moldean cambios evolutivos o que llevan a las poblaciones al vórtice de la extinción. Las invasiones biológicas, aunque han generado pérdidas considerables en la diversidad biológica, ofrecen un escenario interesante para estudiar procesos evolutivos contemporáneos.This paper reviews three of the main threats to biological diversity, such as habitat fragmentation /habitat loss, and invasion of exotic species, mainly from their evolutionary implications. Effects of habitat fragmentation/habitat loss could be addressed by looking at the synergy between demographic and genetic factors that together shape evolutionary changes or otherwise bring populations to extinction vortex. Biological invasions, in spite of their strong negative effects on biological diversity, offer an interesting scenario to study contemporary evolutionary processes.

  7. Essential role of Bmp signaling and its positive feedback loop in the early cell fate evolution of chordates

    OpenAIRE

    Kozmiková, I. (Iryna); S Candiani; P. Fabian; Gurská, D. (Daniela); Kozmik, Z

    2013-01-01

    In chordates, early separation of cell fate domains occurs prior to the final specification of ectoderm to neural and non-neural as well as mesoderm to dorsal and ventral during development. Maintaining such division with the establishment of an exact border between the domains is required for the formation of highly differentiated structures such as neural tube and notochord. We hypothesized that the key condition for efficient cell fate separation in a chordate embryo is the presence of a p...

  8. Evolution of retinoic acid receptors in chordates: insights from three lamprey species, Lampetra fluviatilis, Petromyzon marinus, and Lethenteron japonicum

    OpenAIRE

    Campo-Paysaa, Florent; Jandzik, David; Takio-Ogawa, Yoko; Cattell, Maria V; Neef, Haley C; Langeland, James A.; Kuratani, Shigeru; Medeiros, Daniel M.; Mazan, Sylvie; Kuraku, Shigehiro; Laudet, Vincent; Schubert, Michael

    2015-01-01

    Background Retinoic acid (RA) signaling controls many developmental processes in chordates, from early axis specification to late organogenesis. The functions of RA are chiefly mediated by a subfamily of nuclear hormone receptors, the retinoic acid receptors (RARs), that act as ligand-activated transcription factors. While RARs have been extensively studied in jawed vertebrates (that is, gnathostomes) and invertebrate chordates, very little is known about the repertoire and developmental role...

  9. Ancient homeobox gene loss and the evolution of chordate brain and pharynx development : deductions from amphioxus gene expression

    OpenAIRE

    Butts, Thomas; Holland, Peter W. H.; Ferrier, David Ellard Keith

    2010-01-01

    Homeobox genes encode a large superclass of transcription factors with widespread roles in animal development. Within chordates there are over 100 homeobox genes in the invertebrate cephalochordate amphioxus and over 200 in humans. Set against this general trend of increasing gene number in vertebrate evolution, some ancient homeobox genes that were present in the last common ancestor of chordates have been lost from vertebrates. Here, we describe the embryonic expression of four amphioxus de...

  10. Retinoic acid influences anteroposterior positioning of epidermal sensory neurons and their gene expression in a developing chordate (amphioxus)

    OpenAIRE

    Schubert, Michael; Holland, Nicholas D; Escriva, Hector; Holland, Linda Z; Laudet, Vincent

    2004-01-01

    In developing chordates, retinoic acid (RA) signaling patterns the rostrocaudal body axis globally and affects gene expression locally in some differentiating cell populations. Here we focus on development of epidermal sensory neurons in an invertebrate chordate (amphioxus) to determine how RA signaling influences their rostrocaudal distribution and gene expression (for AmphiCoe, a neural precursor gene; for amphioxus islet and AmphiERR, two neural differentiation genes; and for AmphiHox1, -3...

  11. The Emergence of New Industries in Space: An evolutionary understanding of industry emergence from a geographical perspective

    DEFF Research Database (Denmark)

    Tanner, Anne Nygaard

    This paper claims that in the field of economic geography, research questions about how new industries emerge and the degree to which their emergence are anchored in regional economies are less commonly studied than concepts of for example localisation economies and clusters. Consequently......, the paper draws on the recent conceptual framework of ‘regional branching’ that is able to capture the emergence of new industries in their geographical context. Regional branching builds on the evolutionary understanding of industry development and modifies previous understanding of industry emergence...

  12. Amphioxus: a peaceful anchovy fillet to illuminate Chordate Evolution (I

    Directory of Open Access Journals (Sweden)

    2006-04-01

    Full Text Available The cephalochordate amphioxus occupies a central place in evolutionary thoughts to the origin of Vertebrates. With a prototypical vertebrate-like body plan and a preduplicative genome, the friendly lancelet seems to be in morphological and genetic motionless since its separation from the major branch of evolution that eventually ended up in our corner in the Animal Kingdom. This makes it an ideal model system with which, with the current development of genomic and experimental tools, an Evo-Devo approach to the understanding of the origin of vertebrates looks proper, reliable, and excitingly promising.

  13. Evolution of the role of RA and FGF signals in the control of somitogenesis in chordates

    OpenAIRE

    Stéphanie Bertrand; Daniel Aldea; Silvan Oulion; Lucie Subirana; de Lera, Angel R.; Ildiko Somorjai; Hector Escriva

    2015-01-01

    During vertebrate development, the paraxial mesoderm becomes segmented, forming somites that will give rise to dermis, axial skeleton and skeletal muscles. Although recently challenged, the "clock and wavefront" model for somitogenesis explains how interactions between several cell-cell communication pathways, including the FGF, RA, Wnt and Notch signals, control the formation of these bilateral symmetric blocks. In the cephalochordate amphioxus, which belongs to the chordate phylum together ...

  14. Evolution of anterior Hox regulatory elements among chordates

    OpenAIRE

    Natale Alfonso; Sims Carrie; Chiusano Maria L; Amoroso Alessandro; D'Aniello Enrico; Fucci Laura; Krumlauf Robb; Branno Margherita; Locascio Annamaria

    2011-01-01

    Abstract Background The Hox family of transcription factors has a fundamental role in segmentation pathways and axial patterning of embryonic development and their clustered organization is linked with the regulatory mechanisms governing their coordinated expression along embryonic axes. Among chordates, of particular interest are the Hox paralogous genes in groups 1-4 since their expression is coupled to the control of regional identity in the anterior nervous system, where the highest struc...

  15. Diversification of the expression patterns and developmental functions of the Dishevelled gene family during chordate evolution

    OpenAIRE

    Gray, Ryan S.; Bayly, Robbie D.; Green, Stephen A.; Agarwala, Seema; Lowe, Christopher J.; Wallingford, John B.

    2009-01-01

    Dishevelled (Dvl) proteins are key transducers of Wnt signaling encoded by members of a multi-gene family in vertebrates. We report here the divergent, tissue-specific expression patterns for all three Dvl genes in Xenopus embryos, which contrast dramatically with their expression patterns in mice. Moreover, we find that the expression patterns of Dvl genes in the chick diverge significantly from those of Xenopus. In addition, in hemichordates, an outgroup to chordates, we find that the one D...

  16. The Transcriptome of an Amphioxus, Asymmetron lucayanum, from the Bahamas: A Window into Chordate Evolution

    OpenAIRE

    Yue, Jia-Xing; Yu, Jr-Kai; Putnam, Nicholas H.; Holland, Linda Z

    2014-01-01

    Cephalochordates, the sister group of tunicates plus vertebrates, have been called “living fossils” due to their resemblance to fossil chordates from Cambrian strata. The genome of the cephalochordate Branchiostoma floridae shares remarkable synteny with vertebrates and is free from whole-genome duplication. We performed RNA sequencing from larvae and adults of Asymmetron lucayanum, a cephalochordate distantly related to B. floridae. Comparisons of about 430 orthologous gene groups among both...

  17. Evolution of the chordate body plan: New insights from phylogenetic analyses of deuterostome phyla

    OpenAIRE

    Cameron, Chris B.; Garey, James R.; Swalla, Billie J.

    2000-01-01

    The deuterostome phyla include Echinodermata, Hemichordata, and Chordata. Chordata is composed of three subphyla, Vertebrata, Cephalochordata (Branchiostoma), and Urochordata (Tunicata). Careful analysis of a new 18S rDNA data set indicates that deuterostomes are composed of two major clades: chordates and echinoderms + hemichordates. This analysis strongly supports the monophyly of each of the four major deuterostome taxa: Vertebrata + Cephalochordata, Urochordata, Hemichordata, and Echinode...

  18. Evolution of the Role of RA and FGF Signals in the Control of Somitogenesis in Chordates.

    Directory of Open Access Journals (Sweden)

    Stéphanie Bertrand

    Full Text Available During vertebrate development, the paraxial mesoderm becomes segmented, forming somites that will give rise to dermis, axial skeleton and skeletal muscles. Although recently challenged, the "clock and wavefront" model for somitogenesis explains how interactions between several cell-cell communication pathways, including the FGF, RA, Wnt and Notch signals, control the formation of these bilateral symmetric blocks. In the cephalochordate amphioxus, which belongs to the chordate phylum together with tunicates and vertebrates, the dorsal paraxial mesendoderm also periodically forms somites, although this process is asymmetric and extends along the whole body. It has been previously shown that the formation of the most anterior somites in amphioxus is dependent upon FGF signalling. However, the signals controlling somitogenesis during posterior elongation in amphioxus are still unknown. Here we show that, contrary to vertebrates, RA and FGF signals act independently during posterior elongation and that they are not mandatory for posterior somites to form. Moreover, we show that RA is not able to buffer the left/right asymmetry machinery that is controlled through the asymmetric expression of Nodal pathway actors. Our results give new insights into the evolution of the somitogenesis process in chordates. They suggest that RA and FGF pathways have acquired specific functions in the control of somitogenesis in vertebrates. We propose that the "clock and wavefront" system was selected specifically in vertebrates in parallel to the development of more complex somite-derived structures but that it was not required for somitogenesis in the ancestor of chordates.

  19. Evolutionary perspectives on collective decision making: Studying the implications of diversity and social network structure with agent-based simulations

    CERN Document Server

    Sayama, Hiroki; Yammarino, Francis J

    2013-01-01

    Collective, especially group-based, managerial decision making is crucial in organizations. Using an evolutionary theory approach to collective decision making, agent-based simulations were conducted to investigate how collective decision making would be affected by the agents' diversity in problem understanding and/or behavior in discussion, as well as by their social network structure. Simulation results indicated that groups with consistent problem understanding tended to produce higher utility values of ideas and displayed better decision convergence, but only if there was no group-level bias in collective problem understanding. Simulation results also indicated the importance of balance between selection-oriented (i.e., exploitative) and variation-oriented (i.e., explorative) behaviors in discussion to achieve quality final decisions. Expanding the group size and introducing non-trivial social network structure generally improved the quality of ideas at the cost of decision convergence. Simulations with ...

  20. Toward an evolutionary perspective on conceptual representation: species-specific calls activate visual and affective processing systems in the macaque.

    Science.gov (United States)

    Gil-da-Costa, Ricardo; Braun, Allen; Lopes, Marco; Hauser, Marc D; Carson, Richard E; Herscovitch, Peter; Martin, Alex

    2004-12-14

    Non-human primates produce a diverse repertoire of species-specific calls and have rich conceptual systems. Some of their calls are designed to convey information about concepts such as predators, food, and social relationships, as well as the affective state of the caller. Little is known about the neural architecture of these calls, and much of what we do know is based on single-cell physiology from anesthetized subjects. By using positron emission tomography in awake rhesus macaques, we found that conspecific vocalizations elicited activity in higher-order visual areas, including regions in the temporal lobe associated with the visual perception of object form (TE/TEO) and motion (superior temporal sulcus) and storing visual object information into long-term memory (TE), as well as in limbic (the amygdala and hippocampus) and paralimbic regions (ventromedial prefrontal cortex) associated with the interpretation and memory-encoding of highly salient and affective material. This neural circuitry strongly corresponds to the network shown to support representation of conspecifics and affective information in humans. These findings shed light on the evolutionary precursors of conceptual representation in humans, suggesting that monkeys and humans have a common neural substrate for representing object concepts. PMID:15583132

  1. Flagellar movement in two bacteria of the family rickettsiaceae: a re-evaluation of motility in an evolutionary perspective.

    Directory of Open Access Journals (Sweden)

    Claudia Vannini

    Full Text Available Bacteria of the family Rickettsiaceae have always been largely studied not only for their importance in the medical field, but also as model systems in evolutionary biology. In fact, they share a recent common ancestor with mitochondria. The most studied species, belonging to genera Rickettsia and Orientia, are hosted by terrestrial arthropods and include many human pathogens. Nevertheless, recent findings show that a large part of Rickettsiaceae biodiversity actually resides outside the group of well-known pathogenic bacteria. Collecting data on these recently described non-conventional members of the family is crucial in order to gain information on ancestral features of the whole group. Although bacteria of the family Rickettsiaceae, and of the whole order Rickettsiales, are formally described as non-flagellated prokaryotes, some recent findings renewed the debate about this feature. In this paper we report the first finding of members of the family displaying numerous flagella and active movement inside their host cells. These two new taxa are hosted in aquatic environments by protist ciliates and are described here by means of ultrastructural and molecular characterization. Data here reported suggest that the ancestor of Rickettsiales displayed flagellar movement and re-evaluate the hypothesis that motility played a key-role in the origin of mitochondria. Moreover, our study highlights that the aquatic environment represents a well exploited habitat for bacteria of the family Rickettsiaceae. Our results encourage a deep re-consideration of ecological and morphological traits of the family and of the whole order.

  2. Flagellar movement in two bacteria of the family rickettsiaceae: a re-evaluation of motility in an evolutionary perspective.

    Science.gov (United States)

    Vannini, Claudia; Boscaro, Vittorio; Ferrantini, Filippo; Benken, Konstantin A; Mironov, Timofei I; Schweikert, Michael; Görtz, Hans-Dieter; Fokin, Sergei I; Sabaneyeva, Elena V; Petroni, Giulio

    2014-01-01

    Bacteria of the family Rickettsiaceae have always been largely studied not only for their importance in the medical field, but also as model systems in evolutionary biology. In fact, they share a recent common ancestor with mitochondria. The most studied species, belonging to genera Rickettsia and Orientia, are hosted by terrestrial arthropods and include many human pathogens. Nevertheless, recent findings show that a large part of Rickettsiaceae biodiversity actually resides outside the group of well-known pathogenic bacteria. Collecting data on these recently described non-conventional members of the family is crucial in order to gain information on ancestral features of the whole group. Although bacteria of the family Rickettsiaceae, and of the whole order Rickettsiales, are formally described as non-flagellated prokaryotes, some recent findings renewed the debate about this feature. In this paper we report the first finding of members of the family displaying numerous flagella and active movement inside their host cells. These two new taxa are hosted in aquatic environments by protist ciliates and are described here by means of ultrastructural and molecular characterization. Data here reported suggest that the ancestor of Rickettsiales displayed flagellar movement and re-evaluate the hypothesis that motility played a key-role in the origin of mitochondria. Moreover, our study highlights that the aquatic environment represents a well exploited habitat for bacteria of the family Rickettsiaceae. Our results encourage a deep re-consideration of ecological and morphological traits of the family and of the whole order.

  3. Rationality of expectations: comparison of neoclassical and evolutionary approaches

    OpenAIRE

    Emilia Tomczyk

    2006-01-01

    Paper compares two major schools of economic thought – neoclassical and evolutionary – from the perspective of keystone assumption: rationality of economic agents. It discusses role of rationality assumption in neoclassical and evolutionary theories; importance of expectations; and perspectives for analyzing them within the framework of evolutionary game theory – namely, through replicator dynamics.

  4. mRNA 5′-leader trans-splicing in the chordates

    OpenAIRE

    Vandenberghe, Amanda E.; Meedel, Thomas H.; Hastings, Kenneth E.M.

    2001-01-01

    We report the discovery of mRNA 5′-leader trans-splicing (SL trans-splicing) in the chordates. In the ascidian protochordate Ciona intestinalis, the mRNAs of at least seven genes undergo trans-splicing of a 16-nucleotide 5′-leader apparently derived from a 46-nucleotide RNA that shares features with previously characterized splice donor SL RNAs. SL trans-splicing was known previously to occur in several protist and metazoan phyla, however, this is the first report of SL trans-splicing within ...

  5. Evolutionary Demography

    DEFF Research Database (Denmark)

    Levitis, Daniel

    2015-01-01

    of biological and cultural evolution. Demographic variation within and among human populations is influenced by our biology, and therefore by natural selection and our evolutionary background. Demographic methods are necessary for studying populations of other species, and for quantifying evolutionary fitness...

  6. Life History Theory:An Evolutionary Perspective on Human Development%生命史理论:进化视角下的生命发展观

    Institute of Scientific and Technical Information of China (English)

    林镇超; 王燕

    2015-01-01

    From the traditional psychological perspectives of human development, it was generally taken for granted that individual biological development was a fixed routine, rarely had experiences in childhood been taken into consideration systematically. However, life history theory, as a branch of evolutionary biology, focusing on how organisms allocate time, energy as well as resources to various activities over their life cycle, pointed out that childhood experiences could influence individual’s somatic development and then reproductive strategy. Such an understanding implied an interaction, especially with a developmental perspective, between body and mind. Thus, the timing of sexual maturation (i.e., puberty) was a core variable distinguishing other theories of human development from life history theory.%传统的心理学研究很少从发展角度系统地考察童年早期经历和个体生物性发展之间的关系。然而,以进化理论为基础的生命史理论的研究表明,个体的幼年环境会影响一系列生命史事件的出现和持续时间。其要义在于,为了最大限度地成功繁衍,个体会根据环境线索来做出关乎生存和繁衍的具有适应性的权衡。特别地,性成熟时间是生命史理论区别于其他人类发展理论的核心变量。未来的研究一方面需要深入挖掘人类社会规范在生命史权衡中的意义,另一方面还要继续探索实证研究的新方法。

  7. Applying evolutionary anthropology.

    Science.gov (United States)

    Gibson, Mhairi A; Lawson, David W

    2015-01-01

    Evolutionary anthropology provides a powerful theoretical framework for understanding how both current environments and legacies of past selection shape human behavioral diversity. This integrative and pluralistic field, combining ethnographic, demographic, and sociological methods, has provided new insights into the ultimate forces and proximate pathways that guide human adaptation and variation. Here, we present the argument that evolutionary anthropological studies of human behavior also hold great, largely untapped, potential to guide the design, implementation, and evaluation of social and public health policy. Focusing on the key anthropological themes of reproduction, production, and distribution we highlight classic and recent research demonstrating the value of an evolutionary perspective to improving human well-being. The challenge now comes in transforming relevance into action and, for that, evolutionary behavioral anthropologists will need to forge deeper connections with other applied social scientists and policy-makers. We are hopeful that these developments are underway and that, with the current tide of enthusiasm for evidence-based approaches to policy, evolutionary anthropology is well positioned to make a strong contribution.

  8. Ontology for the asexual development and anatomy of the colonial chordate Botryllus schlosseri.

    Directory of Open Access Journals (Sweden)

    Lucia Manni

    Full Text Available Ontologies provide an important resource to integrate information. For developmental biology and comparative anatomy studies, ontologies of a species are used to formalize and annotate data that are related to anatomical structures, their lineage and timing of development. Here, we have constructed the first ontology for anatomy and asexual development (blastogenesis of a bilaterian, the colonial tunicate Botryllus schlosseri. Tunicates, like Botryllus schlosseri, are non-vertebrates and the only chordate taxon species that reproduce both sexually and asexually. Their tadpole larval stage possesses structures characteristic of all chordates, i.e. a notochord, a dorsal neural tube, and gill slits. Larvae settle and metamorphose into individuals that are either solitary or colonial. The latter reproduce both sexually and asexually and these two reproductive modes lead to essentially the same adult body plan. The Botryllus schlosseri Ontology of Development and Anatomy (BODA will facilitate the comparison between both types of development. BODA uses the rules defined by the Open Biomedical Ontologies Foundry. It is based on studies that investigate the anatomy, blastogenesis and regeneration of this organism. BODA features allow the users to easily search and identify anatomical structures in the colony, to define the developmental stage, and to follow the morphogenetic events of a tissue and/or organ of interest throughout asexual development. We invite the scientific community to use this resource as a reference for the anatomy and developmental ontology of B. schlosseri and encourage recommendations for updates and improvements.

  9. The transcriptome of an amphioxus, Asymmetron lucayanum, from the Bahamas: a window into chordate evolution.

    Science.gov (United States)

    Yue, Jia-Xing; Yu, Jr-Kai; Putnam, Nicholas H; Holland, Linda Z

    2014-10-01

    Cephalochordates, the sister group of tunicates plus vertebrates, have been called "living fossils" due to their resemblance to fossil chordates from Cambrian strata. The genome of the cephalochordate Branchiostoma floridae shares remarkable synteny with vertebrates and is free from whole-genome duplication. We performed RNA sequencing from larvae and adults of Asymmetron lucayanum, a cephalochordate distantly related to B. floridae. Comparisons of about 430 orthologous gene groups among both cephalochordates and 10 vertebrates using an echinoderm, a hemichordate, and a mollusk as outgroups showed that cephalochordates are evolving more slowly than the slowest evolving vertebrate known (the elephant shark), with A. lucayanum evolving even more slowly than B. floridae. Against this background of slow evolution, some genes, notably several involved in innate immunity, stand out as evolving relatively quickly. This may be due to the lack of an adaptive immune system and the relatively high levels of bacteria in the inshore waters cephalochordates inhabit. Molecular dating analysis including several time constraints revealed a divergence time of ∼120 Ma for A. lucayanum and B. floridae. The divisions between cephalochordates and vertebrates, and that between chordates and the hemichordate plus echinoderm clade likely occurred before the Cambrian. PMID:25240057

  10. Structural and functional insights into the ligand-binding domain of a nonduplicated retinoid X nuclear receptor from the invertebrate chordate amphioxus.

    Science.gov (United States)

    Tocchini-Valentini, Giuseppe D; Rochel, Natacha; Escriva, Hector; Germain, Pierre; Peluso-Iltis, Carole; Paris, Mathilde; Sanglier-Cianferani, Sarah; Van Dorsselaer, Alain; Moras, Dino; Laudet, Vincent

    2009-01-16

    Retinoid X nuclear receptors (RXRs), as well as their insect orthologue, ultraspiracle protein (USP), play an important role in the transcription regulation mediated by the nuclear receptors as the common partner of many other nuclear receptors. Phylogenetic and structural studies have shown that the several evolutionary shifts have modified the ligand binding ability of RXRs. To understand the vertebrate-specific character of RXRs, we have studied the RXR ligand-binding domain of the cephalochordate amphioxus (Branchiostoma floridae), an invertebrate chordate that predates the genome duplication that produced the three vertebrates RXRs (alpha, beta, and gamma). Here we report the crystal structure of a novel apotetramer conformation of the AmphiRXR ligand-binding domain, which shows some similarity with the structures of the arthropods RXR/USPs. AmphiRXR adopts an apo antagonist conformation with a peculiar conformation of helix H11 filling the binding pocket. In contrast to the arthropods RXR/USPs, which cannot be activated by any RXR ligands, our functional data show that AmphiRXR, like the vertebrates/mollusk RXRs, is able to bind and be activated by RXR ligands but less efficiently than vertebrate RXRs. Our data suggest that amphioxus RXR is, functionally, an intermediate between arthropods RXR/USPs and vertebrate RXRs. PMID:18986992

  11. The evolutionary psychology of hunger.

    Science.gov (United States)

    Al-Shawaf, Laith

    2016-10-01

    An evolutionary psychological perspective suggests that emotions can be understood as coordinating mechanisms whose job is to regulate various psychological and physiological programs in the service of solving an adaptive problem. This paper suggests that it may also be fruitful to approach hunger from this coordinating mechanism perspective. To this end, I put forward an evolutionary task analysis of hunger, generating novel a priori hypotheses about the coordinating effects of hunger on psychological processes such as perception, attention, categorization, and memory. This approach appears empirically fruitful in that it yields a bounty of testable new hypotheses. PMID:27328100

  12. Deciphering deuterostome phylogeny: molecular, morphological and palaeontological perspectives

    OpenAIRE

    Swalla, Billie J.; Smith, Andrew B.

    2008-01-01

    Deuterostomes are a monophyletic group of animals that include the vertebrates, invertebrate chordates, ambulacrarians and xenoturbellids. Fossil representatives from most major deuterostome groups, including some phylum-level crown groups, are found in the Lower Cambrian, suggesting that evolutionary divergence occurred in the Late Precambrian, in agreement with some molecular clock estimates. Molecular phylogenies, larval morphology and the adult heart/kidney complex all support echinoderms...

  13. Evolutionary Economics

    OpenAIRE

    Dopfer, Kurt

    2006-01-01

    The paper provides an overview of major recent contributions in evolutionary economics. It starts of demonstrating that the pioneers of this approach such as Veblen, Schumpeter, Marshall and Hayek saw the economy as continuously changing and that this kind of "realism of perception" guides essentially also contemporary evolutionary economics. The economy is viewed as an evolving system of structured knowledge governing economic operations. Theoretically, a micro-meso-macro architecture is pro...

  14. Adult Neurogenesis: An Evolutionary Perspective.

    Science.gov (United States)

    Kempermann, Gerd

    2016-02-01

    When adult neurogenesis was discovered in the mammalian brain it was often considered an atavism and, even today, many people are convinced that there has been a "phylogenetic reduction" away from lifelong neurogenesis, favoring stability for complex brains. Adult neurogenesis is found throughout the animal kingdom but varies to a large extent. Mammals might have fewer neurogenic zones than, for example, fish, but within their remaining neurogenic zones, the new neurons are highly functional. Especially, humans have very substantial quantities of neurogenesis in their hippocampus. At least for the mammalian dentate gyrus, one can thus argue that there has been evolution toward neurogenesis-based plasticity rather than away from it. PMID:26684183

  15. Values From an Evolutionary Perspective

    Science.gov (United States)

    Calhoun, John B.

    1972-01-01

    Continuation of life and evolution as criteria for development of a value system are analyzed. Discussion is based on an awareness aspect of evolution which promotes a greater harmony of response with existing and emerging environmental conditions. (BL)

  16. Evolutionary Path and Development Strategy of Green Logistics in China:A Low-carbon Perspective%低碳经济视角下我国绿色物流的演化路径与发展策略

    Institute of Scientific and Technical Information of China (English)

    赵胜男

    2014-01-01

    论述了低碳经济视角下我国绿色物流的演化路径,分析了我国绿色物流发展中的问题,提出了低碳经济视角下我国绿色物流的发展策略。%In this paper, we elaborated on the evolutionary path of the green logistics industry in China from the perspective of low-carbon economy, then analyzed the problems existing therein, and at the end, proposed the corresponding strategy for its better development.

  17. The emerging empirics of evolutionary economic geography

    OpenAIRE

    Boschma, RA; Frenken, K Koen

    2010-01-01

    Following last decade’s programmatic papers on Evolutionary Economic Geography, we report on recent empirical advances and how this empirical work can be positioned vis-à-vis other strands of research in economic geography. First, we review studies on the path dependent nature of clustering, and how the evolutionary perspective relates to that of New Economic Geography. Second, we discuss research on agglomeration externalities in Regional Science, and how Evolutionary Economic Geography cont...

  18. Evolutionary macroecology

    Directory of Open Access Journals (Sweden)

    José Alexandre F. Diniz-Filho

    2013-10-01

    Full Text Available Macroecology focuses on ecological questions at broad spatial and temporal scales, providing a statistical description of patterns in species abundance, distribution and diversity. More recently, historical components of these patterns have begun to be investigated more deeply. We tentatively refer to the practice of explicitly taking species history into account, both analytically and conceptually, as ‘evolutionary macroecology’. We discuss how the evolutionary dimension can be incorporated into macroecology through two orthogonal and complementary data types: fossils and phylogenies. Research traditions dealing with these data have developed more‐or‐less independently over the last 20–30 years, but merging them will help elucidate the historical components of diversity gradients and the evolutionary dynamics of species’ traits. Here we highlight conceptual and methodological advances in merging these two research traditions and review the viewpoints and toolboxes that can, in combination, help address patterns and unveil processes at temporal and spatial macro‐scales.

  19. Evolutionary Expectations

    DEFF Research Database (Denmark)

    Nash, Ulrik William

    2014-01-01

    The concept of evolutionary expectations descends from cue learning psychology, synthesizing ideas on rational expectations with ideas on bounded rationality, to provide support for these ideas simultaneously. Evolutionary expectations are rational, but within cognitive bounds. Moreover......, they are correlated among people who share environments because these individuals satisfice within their cognitive bounds by using cues in order of validity, as opposed to using cues arbitrarily. Any difference in expectations thereby arise from differences in cognitive ability, because two individuals with identical...... cognitive bounds will perceive business opportunities identically. In addition, because cues provide information about latent causal structures of the environment, changes in causality must be accompanied by changes in cognitive representations if adaptation is to be maintained. The concept of evolutionary...

  20. A glycine receptor is involved in the organization of swimming movements in an invertebrate chordate

    Directory of Open Access Journals (Sweden)

    Okamura Yasushi

    2010-01-01

    Full Text Available Abstract Background Rhythmic motor patterns for locomotion in vertebrates are generated in spinal cord neural networks known as spinal Central Pattern Generators (CPGs. A key element in pattern generation is the role of glycinergic synaptic transmission by interneurons that cross the cord midline and inhibit contralaterally-located excitatory neurons. The glycinergic inhibitory drive permits alternating and precisely timed motor output during locomotion such as walking or swimming. To understand better the evolution of this system we examined the physiology of the neural network controlling swimming in an invertebrate chordate relative of vertebrates, the ascidian larva Ciona intestinalis. Results A reduced preparation of the larva consisting of nerve cord and motor ganglion generates alternating swimming movements. Pharmacological and genetic manipulation of glycine receptors shows that they are implicated in the control of these locomotory movements. Morphological molecular techniques and heterologous expression experiments revealed that glycine receptors are inhibitory and are present on both motoneurones and locomotory muscle while putative glycinergic interneurons were identified in the nerve cord by labeling with an anti-glycine antibody. Conclusions In Ciona intestinalis, glycine receptors, glycinergic transmission and putative glycinergic interneurons, have a key role in coordinating swimming movements through a simple CPG that is present in the motor ganglion and nerve cord. Thus, the strong association between glycine receptors and vertebrate locomotory networks may now be extended to include the phylum chordata. The results suggest that the basic network for 'spinal-like' locomotion is likely to have existed in the common ancestor of extant chordates some 650 M years ago.

  1. Cell signaling and transcription factor genes expressed during whole body regeneration in a colonial chordate

    Directory of Open Access Journals (Sweden)

    Rinkevich Baruch

    2008-10-01

    Full Text Available Abstract Background The restoration of adults from fragments of blood vessels in botryllid ascidians (termed whole body regeneration [WBR] represents an inimitable event in the chordates, which is poorly understood on the mechanistic level. Results To elucidate mechanisms underlying this phenomenon, a subtracted EST library for early WBR stages was previously assembled, revealing 76 putative genes belonging to major signaling pathways, including Notch/Delta, JAK/STAT, protein kinases, nuclear receptors, Ras oncogene family members, G-Protein coupled receptor (GPCR and transforming growth factor beta (TGF-β signaling. RT-PCR on selected transcripts documented specific up-regulation in only regenerating fragments, pointing to a broad activation of these signaling pathways at onset of WBR. The followed-up expression pattern of seven representative transcripts from JAK/STAT signaling (Bl-STAT, the Ras oncogene family (Bl-Rap1A, Bl-Rab-33, the protein kinase family (Bl-Mnk, Bl-Cnot, Bl-Slit and Bl-Bax inhibitor, revealed systemic and site specific activations during WBR in a sub-population of circulatory cells. Conclusion WBR in the non-vertebrate chordate Botrylloides leachi is a multifaceted phenomenon, presided by a complex array of cell signaling and transcription factors. Above results, provide a first insight into the whole genome molecular machinery of this unique regeneration process, and reveal the broad participation of cell signaling and transcription factors in the process. While regeneration involves the participation of specific cell populations, WBR signals are systemically expressed at the organism level.

  2. A systemic framework for the computational analysis of complex economies: An evolutionary-institutional perspective on the ontology, epistemology, and methodology of complexity economics

    OpenAIRE

    Gräbner, Claudius

    2016-01-01

    This theses introduces the idea of a symbiotic relationship between evolutionary-institutional and complexity economics. It consists of two major contributions: The first contribution focuses on how the emerging research program of complexity economics can benefit from evolutionary-institutional theory. I show that complexity economics still lacks an adequate philosophical foundation. I explicate why such a foundation is needed if complexity economics is to promote further scientific progress...

  3. Evolutionary medicine.

    Science.gov (United States)

    Swynghedauw, B

    2004-04-01

    Nothing in biology makes sense except in the light of evolution. Evolutionary, or darwinian, medicine takes the view that contemporary diseases result from incompatibility between the conditions under which the evolutionary pressure had modified our genetic endowment and the lifestyle and dietary habits in which we are currently living, including the enhanced lifespan, the changes in dietary habits and the lack of physical activity. An evolutionary trait express a genetic polymorphism which finally improve fitness, it needs million years to become functional. A limited genetic diversity is a necessary prerequisite for evolutionary medicine. Nevertheless, search for a genetic endowment would become nearly impossible if the human races were genetically different. From a genetic point of view, homo sapiens, is homogeneous, and the so-called human races have only a socio-economic definition. Historically, Heart Failure, HF, had an infectious origin and resulted from mechanical overload which triggered mechanoconversion by using phylogenically ancient pleiotropic pathways. Adaptation was mainly caused by negative inotropism. Recently, HF was caused by a complex remodelling caused by the trophic effects of mechanics, ischemia, senescence, diabetes and, neurohormones. The generally admitted hypothesis is that cancers were largely caused by a combination of modern reproductive and dietary lifestyles mismatched with genotypic traits, plus the longer time available for a confrontation. Such a concept is illustrated for skin and breast cancers, and also for the link between cancer risk and dietary habits.

  4. On Mate Selection in Anna of the Five Towns from the Perspective of Evolutionary Psychology%从进化心理学视角看《五镇的安娜》中的配偶选择

    Institute of Scientific and Technical Information of China (English)

    娄淑洪

    2012-01-01

    Anna of the Five Towns is one of Arnold Bennett's "Five Towns" fictional series.It depicts the life of the ordinary people which lived in the Potteries,representing the evolutionary thought of the author.It is an important work in English literary history.However,the study of Arnold Bennett and his works in China has still been scanty so far.This paper attempts to study the mate selection of the main figures in the novel from the perspective of Evolutionary Psychology,mainly female and male preferences in the mate selection,so as to demonstrate the view of evolutionary world of Arnold Bennett and expose that the evolutionary thought exerts an intense impact on the behavior of characters and plot development in this novel.%《五镇的安娜》系阿诺德·贝内特的"五镇"系列小说的一部。它描述了英国著名的陶瓷产地"五镇"的普通人的生活,体现了作者的进化论思想。这部小说虽然在英国文学史上占有一定地位,但是在中国对阿诺德·贝内特及其作品的研究近乎是空白。文章拟用进化心理学中女性和男性择偶倾向来研究《五镇的安娜》中主要人物的配偶选择,揭示阿诺德·贝内特的进化论世界观以及进化思想在该小说人物行为和情节安排中发挥着重要作用。

  5. A new vetulicolian from Australia and its bearing on the chordate affinities of an enigmatic Cambrian group

    OpenAIRE

    García-Bellido, Diego C.; Lee, Michael S. Y.; Gregory D. Edgecombe; Jago, James B; Gehling, James G; Paterson, John R

    2014-01-01

    Background Vetulicolians are one of the most problematic and controversial Cambrian fossil groups, having been considered as arthropods, chordates, kinorhynchs, or their own phylum. Mounting evidence suggests that vetulicolians are deuterostomes, but affinities to crown-group phyla are unresolved. Results A new vetulicolian from the Emu Bay Shale Konservat-Lagerstätte, South Australia, Nesonektris aldridgei gen. et sp. nov., preserves an axial, rod-like structure in the posterior body region ...

  6. DoOP: Databases of Orthologous Promoters, collections of clusters of orthologous upstream sequences from chordates and plants

    OpenAIRE

    Barta, Endre; Sebestyén, Endre; Pálfy, Tamás B.; Tóth, Gábor; Ortutay, Csaba P.; Patthy, László

    2004-01-01

    DoOP (http://doop.abc.hu/) is a database of eukaryotic promoter sequences (upstream regions) aiming to facilitate the recognition of regulatory sites conserved between species. The annotated first exons of human and Arabidopsis thaliana genes were used as queries in BLAST searches to collect the most closely related orthologous first exon sequences from Chordata and Viridiplantae species. Up to 3000 bp DNA segments upstream from these first exons constitute the clusters in the chordate and pl...

  7. Evolutionary Psychology

    OpenAIRE

    Heylighen, Francis

    2011-01-01

    Evolutionary psychology (EP) is an approach to the study of the mind that is founded on Darwin’s theory of evolution by natural selection. It assumes that our mental abilities, emotions and preferences are adapted specifically for solving problems of survival and reproduction in humanity’s ancestral environment, and derives testable predictions from this assumption. This has important implications for our understanding of the conditions for human well-being.

  8. Perspectives

    Science.gov (United States)

    Tarone, Elaine

    2013-01-01

    The topic of this "Perspectives" column is "Requiring a Proficiency Level as a Requirement for U.S. K-12 Teacher Licensure." In 1998, the American Council of Teachers of Foreign Languages (ACTFL) began to work with the National Council for Accreditation of Teacher Education (NCATE), which accredits teacher education programs…

  9. Evolutionary mysteries in meiosis.

    Science.gov (United States)

    Lenormand, Thomas; Engelstädter, Jan; Johnston, Susan E; Wijnker, Erik; Haag, Christoph R

    2016-10-19

    Meiosis is a key event of sexual life cycles in eukaryotes. Its mechanistic details have been uncovered in several model organisms, and most of its essential features have received various and often contradictory evolutionary interpretations. In this perspective, we present an overview of these often 'weird' features. We discuss the origin of meiosis (origin of ploidy reduction and recombination, two-step meiosis), its secondary modifications (in polyploids or asexuals, inverted meiosis), its importance in punctuating life cycles (meiotic arrests, epigenetic resetting, meiotic asymmetry, meiotic fairness) and features associated with recombination (disjunction constraints, heterochiasmy, crossover interference and hotspots). We present the various evolutionary scenarios and selective pressures that have been proposed to account for these features, and we highlight that their evolutionary significance often remains largely mysterious. Resolving these mysteries will likely provide decisive steps towards understanding why sex and recombination are found in the majority of eukaryotes.This article is part of the themed issue 'Weird sex: the underappreciated diversity of sexual reproduction'. PMID:27619705

  10. Molecular signatures that are distinctive characteristics of the vertebrates and chordates and supporting a grouping of vertebrates with the tunicates.

    Science.gov (United States)

    Gupta, Radhey S

    2016-01-01

    Members of the phylum Chordata and the subphylum Vertebrata are presently distinguished solely on the basis of morphological characteristics. The relationship of the vertebrates to the two non-vertebrate chordate subphyla is also a subject of debate. Analyses of protein sequences have identified multiple conserved signature indels (CSIs) that are specific for Chordata or for Vertebrata. Five CSIs in 4 important proteins are specific for the Vertebrata, whereas two other CSIs are uniquely found in all sequenced chordate species including Ciona intestinalis and Oikapleura dioica (Tunicates) as well as Branchiostoma floridae (Cephalochordates). The shared presence of these molecular signatures by all vertebrates/chordate species, but in no other animal taxa, strongly indicates that the genetic changes represented by the identified CSIs diagnose monophyletic groups. Two other discovered CSIs are uniquely shared by different vertebrate species and by either one (Ciona intestinalis) or both tunicate (Ciona and Oikapleura) species, but they are not found in Branchiostoma or other animal species. Specific presence of these CSIs in different vertebrates and either one or both tunicate species provides strong independent evidence that the vertebrate species are more closely related to the urochordates (tunicates) than to the cephalochordates. PMID:26419477

  11. Evolutionary thinking

    OpenAIRE

    Hunt, Tam

    2015-01-01

    Evolution as an idea has a lengthy history, even though the idea of evolution is generally associated with Darwin today. Rebecca Stott provides an engaging and thoughtful overview of this history of evolutionary thinking in her 2013 book, Darwin's Ghosts: The Secret History of Evolution. Since Darwin, the debate over evolution—both how it takes place and, in a long war of words with religiously-oriented thinkers, whether it takes place—has been sustained and heated. A growing share of this de...

  12. An evolutionary perspective on perceived parental care and closeness in adolescents: how do biological and social kinship play out within families in the U.S.?

    OpenAIRE

    Sebastian Schnettler; Anja Steinbach

    2011-01-01

    Consistent with inclusive fitness theory, evolutionary biologists predict that individuals care more for their biological than their social children and hence that biological children assess the relationships to their parents better than stepchildren. To test this assumption, we use data from the U.S. National Longitudinal Study of Adolescent Health (Add Health). Unlike many other studies that have been conducted so far, this survey allows us to analyze the consequences of the dynamic between...

  13. Evolutionary perspectives on emotions and their link to intentions, dispositions and behavior. Comment on "The quartet theory of human emotions: An integrative and neurofunctional model" by S. Koelsch et al.

    Science.gov (United States)

    Wildgruber, Dirk; Kreifelts, Benjamin

    2015-06-01

    Koelsch and coworkers present a sophisticated neuroanatomical model of emotions comprising four affect-systems and four output-systems, each bound to a specific brain area [1]. Moreover, they suggest the emergence of distinct components of subjective feelings or "emotion percepts" due to integration of the activation across these subsystems. Incorporating numerous neurobiological, psychological and philosophical findings on human emotions, the model reflects an extensive interdisciplinary approach. Considering an evolutionary perspective, however, we would like to address some issues concerning emotions and their link to intentions, dispositions and behavior that are not fully covered by the Quartet Model. Charles Darwin pointed out that individuals that are better adapted to their environment have increased chances of survival and reproduction. Therefore, natural selection leads to a rising prevalence of properties offering a survival benefit across generations [2]. To better understand the biological functions of emotions we propose to ask the question: How do emotions provide a benefit for survival and reproduction?

  14. Exponential Expansion in Evolutionary Economics

    DEFF Research Database (Denmark)

    Frederiksen, Peter; Jagtfelt, Tue

    2013-01-01

    concepts are described in detail. Taken together it provides the rudimentary aspects of an economic system within an analytical perspective. It is argued that the main dynamic processes of the evolutionary perspective can be reduced to these four concepts. The model and concepts are evaluated in the light......This article attempts to solve current problems of conceptual fragmentation within the field of evolutionary economics. One of the problems, as noted by a number of observers, is that the field suffers from an assemblage of fragmented and scattered concepts (Boschma and Martin 2010). A solution...... to this problem is proposed in the form of a model of exponential expansion. The model outlines the overall structure and function of the economy as exponential expansion. The pictographic model describes four axiomatic concepts and their exponential nature. The interactive, directional, emerging and expanding...

  15. The major synthetic evolutionary transitions.

    Science.gov (United States)

    Solé, Ricard

    2016-08-19

    Evolution is marked by well-defined events involving profound innovations that are known as 'major evolutionary transitions'. They involve the integration of autonomous elements into a new, higher-level organization whereby the former isolated units interact in novel ways, losing their original autonomy. All major transitions, which include the origin of life, cells, multicellular systems, societies or language (among other examples), took place millions of years ago. Are these transitions unique, rare events? Have they instead universal traits that make them almost inevitable when the right pieces are in place? Are there general laws of evolutionary innovation? In order to approach this problem under a novel perspective, we argue that a parallel class of evolutionary transitions can be explored involving the use of artificial evolutionary experiments where alternative paths to innovation can be explored. These 'synthetic' transitions include, for example, the artificial evolution of multicellular systems or the emergence of language in evolved communicating robots. These alternative scenarios could help us to understand the underlying laws that predate the rise of major innovations and the possibility for general laws of evolved complexity. Several key examples and theoretical approaches are summarized and future challenges are outlined.This article is part of the themed issue 'The major synthetic evolutionary transitions'. PMID:27431528

  16. The major synthetic evolutionary transitions

    Science.gov (United States)

    Solé, Ricard

    2016-01-01

    Evolution is marked by well-defined events involving profound innovations that are known as ‘major evolutionary transitions'. They involve the integration of autonomous elements into a new, higher-level organization whereby the former isolated units interact in novel ways, losing their original autonomy. All major transitions, which include the origin of life, cells, multicellular systems, societies or language (among other examples), took place millions of years ago. Are these transitions unique, rare events? Have they instead universal traits that make them almost inevitable when the right pieces are in place? Are there general laws of evolutionary innovation? In order to approach this problem under a novel perspective, we argue that a parallel class of evolutionary transitions can be explored involving the use of artificial evolutionary experiments where alternative paths to innovation can be explored. These ‘synthetic’ transitions include, for example, the artificial evolution of multicellular systems or the emergence of language in evolved communicating robots. These alternative scenarios could help us to understand the underlying laws that predate the rise of major innovations and the possibility for general laws of evolved complexity. Several key examples and theoretical approaches are summarized and future challenges are outlined. This article is part of the themed issue ‘The major synthetic evolutionary transitions’. PMID:27431528

  17. The Simple Chordate Ciona intestinalis Has a Reduced Complement of Genes Associated with Fanconi Anemia

    Science.gov (United States)

    Stanley, Edward C.; Azzinaro, Paul A.; Vierra, David A.; Howlett, Niall G.; Irvine, Steven Q.

    2016-01-01

    Fanconi anemia (FA) is a human genetic disease characterized by congenital defects, bone marrow failure, and increased cancer risk. FA is associated with mutation in one of 24 genes. The protein products of these genes function cooperatively in the FA pathway to orchestrate the repair of DNA interstrand cross-links. Few model organisms exist for the study of FA. Seeking a model organism with a simpler version of the FA pathway, we searched the genome of the simple chordate Ciona intestinalis for homologs of the human FA-associated proteins. BLAST searches, sequence alignments, hydropathy comparisons, maximum likelihood phylogenetic analysis, and structural modeling were used to infer the likelihood of homology between C. intestinalis and human FA proteins. Our analysis indicates that C. intestinalis indeed has a simpler and potentially functional FA pathway. The C. intestinalis genome was searched for candidates for homology to 24 human FA and FA-associated proteins. Support was found for the existence of homologs for 13 of these 24 human genes in C. intestinalis. Members of each of the three commonly recognized FA gene functional groups were found. In group I, we identified homologs of FANCE, FANCL, FANCM, and UBE2T/FANCT. Both members of group II, FANCD2 and FANCI, have homologs in C. intestinalis. In group III, we found evidence for homologs of FANCJ, FANCO, FANCQ/ERCC4, FANCR/RAD51, and FANCS/BRCA1, as well as the FA-associated proteins ERCC1 and FAN1. Evidence was very weak for the existence of homologs in C. intestinalis for any other recognized FA genes. This work supports the notion that C. intestinalis, as a close relative of vertebrates, but having a much reduced complement of FA genes, offers a means of studying the function of certain FA proteins in a simpler pathway than that of vertebrate cells. PMID:27279728

  18. Lifespan extension in a semelparous chordate occurs via developmental growth arrest just prior to meiotic entry.

    Directory of Open Access Journals (Sweden)

    Gunasekaran Subramaniam

    Full Text Available It is proposed that the ageing process is linked to signaling from the germline such that the rate of ageing can be adjusted to the state of the reproductive system, allowing these two processes to co-evolve. Mechanistic insight into this link has been primarily derived from iteroparous reproductive models, the nematode C. elegans, and the arthropod Drosophila. Here, we examined to what extent these mechanisms are evolutionarily conserved in a semelparous chordate, Oikopleura dioica, where we identify a developmental growth arrest (GA in response to crowded, diet-restricted conditions, which can extend its lifespan at least three-fold. Under nutritional stress, the iteroparative models sacrifice germ cells that have entered meiosis, while maintaining a reduced pool of active germline stem cells (GSCs. In contrast, O. dioica only entered GA prior to meiotic entry. Stress conditions encountered after this point led to maturation in a normal time frame but with reduced reproductive output. During GA, TOR signaling was inhibited, whereas MAPK, ERK1/2 and p38 pathways were activated, and under such conditions, activation of these pathways was shown to be critical for survival. Direct inhibition of TOR signaling alone was sufficient to prevent meiotic entry and germline differentiation. This inhibition activated the p38 pathway, but did not activate the ERK1/2 pathway. Thus, the link between reproductive status and lifespan extension in response to nutrient-limited conditions is interpreted in a significantly different manner in these iteroparative versus semelparous models. In the latter case, meiotic entry is a definitive signal that lifespan extension can no longer occur, whereas in the former, meiotic entry is not a unique chronological event, and can be largely erased during lifespan extension in response to nutrient stress, and reactivated from a pool of maintained GSCs when conditions improve.

  19. The candidate histocompatibility locus of a Basal chordate encodes two highly polymorphic proteins.

    Directory of Open Access Journals (Sweden)

    Marie L Nydam

    Full Text Available The basal chordate Botryllus schlosseri undergoes a natural transplantation reaction governed by a single, highly polymorphic locus called the fuhc. Our initial characterization of this locus suggested it encoded a single gene alternatively spliced into two transcripts: a 555 amino acid-secreted form containing the first half of the gene, and a full-length, 1008 amino acid transmembrane form, with polymorphisms throughout the ectodomain determining outcome. We have now found that the locus encodes two highly polymorphic genes which are separated by a 227 bp intergenic region: first, the secreted form as previously described, and a second gene encoding a 531 amino acid membrane-bound gene containing three extracellular immunoglobulin domains. While northern blotting revealed only these two mRNAs, both PCR and mRNA-seq detect a single capped and polyadenylated transcript that encodes processed forms of both genes linked by the intergenic region, as well as other transcripts in which exons of the two genes are spliced together. These results might suggest that the two genes are expressed as an operon, during which both genes are co-transcribed and then trans-spliced into two separate messages. This type of transcriptional regulation has been described in tunicates previously; however, the membrane-bound gene does not encode a typical Splice Leader (SL sequence at the 5' terminus that usually accompanies trans-splicing. Thus, the presence of stable transcripts encoding both genes may suggest a novel mechanism of regulation, or conversely may be rare but stable transcripts in which the two mRNAs are linked due to a small amount of read-through by RNA polymerase. Both genes are highly polymorphic and co-expressed on tissues involved in histocompatibility. In addition, polymorphisms on both genes correlate with outcome, although we have found a case in which it appears that the secreted form may be major allorecognition determinant.

  20. Toward an Evolutionary Theory of Production

    OpenAIRE

    Winter, Sidney G.

    2002-01-01

    Production theory in the neoclassical tradition is strong on Abstract generality. Its high level of Abstraction tends to impede understanding of technological change, partly because its perspective on production differs so much from those of engineers, managers and technologists. A more grounded approach is needed for evolutionary economics, since evolutionary thinking sees questions of production as tightly and reciprocally connected with questions of coordination, incentives, and organizati...

  1. Epigenetic catalysis in an evolutionary context

    OpenAIRE

    Wallace, Dr. Rodrick

    2009-01-01

    Recent work by Ciliberti et al. finds the spinglass model of regulatory gene networks adapted from neural network studies to have a single giant connected component in a metanetwork space of interaction matrices, permitting only gradual evolutionary transition, in conflict with empirical studies of development in sea urchin species that found evidence for punctuated equilibrium evolutionary transition. Shifting perspective from the highly parallel matrix space to the grammar/syntax of the tim...

  2. The evolutionary biology of child health

    OpenAIRE

    Crespi, Bernard

    2011-01-01

    I apply evolutionary perspectives and conceptual tools to analyse central issues underlying child health, with emphases on the roles of human-specific adaptations and genomic conflicts in physical growth and development. Evidence from comparative primatology, anthropology, physiology and human disorders indicates that child health risks have evolved in the context of evolutionary changes, along the human lineage, affecting the timing, growth-differentiation phenotypes and adaptive significanc...

  3. Pax258 and Pax6 alternative splicing events in basal chordates and vertebrates: a focus on paired box domain

    Directory of Open Access Journals (Sweden)

    Peter eFabian

    2015-07-01

    Full Text Available Paired box transcription factors play important role in development and tissue morphogenesis. The number of Pax homologs varies among species studied so far, due to genome and gene duplications that have affected PAX family to a great extent. Based on sequence similarity and functional domains, four Pax classes have been identified in chordates, namely Pax1/9, Pax2/5/8, Pax3/7 and Pax4/6. Numerous splicing events have been reported mainly for Pax2/5/8 and Pax6 genes. Of significant interest are those events that lead to Pax proteins with presumed novel properties, such as altered DNA-binding or transcriptional activity. In the current study, a thorough analysis of Pax2/5/8 splicing events from cephalochordate and vertebrates was performed. We focused more on Pax2/5/8 and Pax6 splicing events in which the paired domain is involved. Three new splicing events were identified in Oryzias latipes, one of which seems to be conserved in Acanthomorphata. Using representatives from deuterostome and protostome phyla, a comparative analysis of the Pax6 exon-intron structure of the paired domain was performed, during an attempt to estimate the time of appearance of the Pax6(5a mRNA isoform. As shown in our analysis, this splicing event is absent in basal chordates and is characteristic of Gnathostomata. Moreover, expression pattern of alternative spliced variants was compared between basal chordates and fish species. In summary, our data indicate expansion of alternative mRNA variants in paired box region of Pax2/5/8 and Pax6 genes during the course of vertebrate evolution.

  4. The central nervous system of sea cucumbers (Echinodermata: Holothuroidea shows positive immunostaining for a chordate glial secretion

    Directory of Open Access Journals (Sweden)

    Grondona Jesus M

    2009-06-01

    Full Text Available Abstract Background Echinoderms and chordates belong to the same monophyletic taxon, the Deuterostomia. In spite of significant differences in body plan organization, the two phyla may share more common traits than was thought previously. Of particular interest are the common features in the organization of the central nervous system. The present study employs two polyclonal antisera raised against bovine Reissner's substance (RS, a secretory product produced by glial cells of the subcomissural organ, to study RS-like immunoreactivity in the central nervous system of sea cucumbers. Results In the ectoneural division of the nervous system, both antisera recognize the content of secretory vacuoles in the apical cytoplasm of the radial glia-like cells of the neuroepithelium and in the flattened glial cells of the non-neural epineural roof epithelium. The secreted immunopositive material seems to form a thin layer covering the cell apices. There is no accumulation of the immunoreactive material on the apical surface of the hyponeural neuroepithelium or the hyponeural roof epithelium. Besides labelling the supporting cells and flattened glial cells of the epineural roof epithelium, both anti-RS antisera reveal a previously unknown putative glial cell type within the neural parenchyma of the holothurian nervous system. Conclusion Our results show that: a the glial cells of the holothurian tubular nervous system produce a material similar to Reissner's substance known to be synthesized by secretory glial cells in all chordates studied so far; b the nervous system of sea cucumbers shows a previously unrealized complexity of glial organization. Our findings also provide significant clues for interpretation of the evolution of the nervous system in the Deuterostomia. It is suggested that echinoderms and chordates might have inherited the RS-producing radial glial cell type from the central nervous system of their common ancestor, i.e., the last common

  5. Retinoic acid signaling acts via Hox1 to establish the posterior limit of the pharynx in the chordate amphioxus

    OpenAIRE

    Schubert, Michael; Yu, Jr-Kai; Holland, Nicholas D; Escriva, Hector; Laudet, Vincent; Holland, Linda Z

    2004-01-01

    In the invertebrate chordate amphioxus, as in vertebrates, retinoic acid (RA) specifies position along the anterior/posterior axis with elevated RA signaling in the middle third of the endoderm setting the posterior limit of the pharynx. Here we show that AmphiHox1 is also expressed in the middle third of the developing amphioxus endoderm and is activated by RA signaling. Knockdown of AmphiHox1 function with an antisense morpholino oligonucleotide shows that AmphiHox1 mediates the role of RA ...

  6. Testing putative hemichordate homologues of the chordate dorsal nervous system and endostyle: expression of NK2.1 (TTF-1) in the acorn worm Ptychodera flava (Hemichordata, Ptychoderidae)

    Science.gov (United States)

    Takacs, Carter M.; Moy, Vanessa N.; Peterson, Kevin J.

    2002-01-01

    Recent phylogenetic investigations have confirmed that hemichordates and echinoderms are sister taxa. However, hemichordates share several cardinal characterstics with chordates and are thus an important taxon for testing hypotheses of homology between key chordate characters and their putative hemichordate antecedents. The chordate dorsal nervous system (DNS) and endostyle are intriguing characters because both hemichordate larval and adult structures have been hypothesized as homologues. This study attempts to test these purported homologies through examination of the expression pattem of a Ptychodera flava NK2 gene, PfNK2.1, because this gene is expressed both in the DNS and endostyle/thyroid in a wide range of chordate taxa. We found that PfNK2.1 is expressed in both neuronal and pharyngeal structures, but its expression pattem is broken up into distinct embryonic and juvenile phases. During embryogenesis, PfNK2.1 is expressed in the apical ectoderm, with transcripts later detected in presumable neuronal structures, including the apical organ and ciliated feeding band. In the developing juvenile we detected PfNK2.1 signal throughout the pharynx, including the stomochord, and later in the hindgut. We conclude that the similar utilization of NK2.1 in apical organ development and chordate DNS is probably due to a more general role for NK2.1 in neurogenesis and that hemichordates do not possess a homologue of the chordate DNS. In addition, we conclude that P. flava most likely does not possess a true endostyle; rather during the evolution of the endostyle NK2.1 was recruited from its more general role in pharynx development.

  7. 演化博弈视角下的高校教学督导机制分析%Analysis on the Teaching Supervision Mechanism of Uni-versity from the Perspective of Evolutionary Game

    Institute of Scientific and Technical Information of China (English)

    刘军

    2015-01-01

    In the teaching supervision mechanism of university, it is difficult for related subjects to never make mistakes in the de-cision-making process, and the optimal strategy can only be achieved by constantly adjusting their strategies. Under the premise of bounded rationality, evolution features of behavioral strategies choice of each subject are studied from the perspective of evolutionary game. Evolutionary stable strategy of teaching su-pervision mechanism of university is explored by stability analy-sis. The study shows that negligence penalties, supervision costs, psychological costs, teaching workload and teaching accident sanctions are the factors influencing teaching supervision mecha-nism of university.%在高校教学督导机制中,相关主体很难在决策过程中从不犯错,只能通过不断调整自己的策略来达到最优策略。在有限理性前提下,从演化博弈视角研究各主体行为策略选择的演变规律,通过稳定性分析探讨高校教学督导机制的演化稳定策略,发现失职处罚、督导费用、心理成本、教学工作量、教学事故处分等因素都会对高校教学督导机制产生影响。

  8. Phylogenetic analysis of the tenascin gene family: evidence of origin early in the chordate lineage

    Directory of Open Access Journals (Sweden)

    Tucker RP

    2006-08-01

    suggests that tenascins may be specific to chordates. Later genomic duplication events led to the appearance of four family members in vertebrates: tenascin-C, tenascin-R, tenascin-W and tenascin-X.

  9. Why isn't everyone an evolutionary psychologist?

    OpenAIRE

    Burke, Darren

    2014-01-01

    Despite a widespread acceptance that the brain that underpins human psychology is the result of biological evolution, very few psychologists in any way incorporate an evolutionary perspective in their research or practice. There have been many attempts to convince mainstream psychology of the importance of such a perspective, mostly from those who identify with “Evolutionary Psychology,” and there has certainly been progress in that direction, but the core of psychology remains essentially un...

  10. Why isn’t everyone an Evolutionary Psychologist?

    OpenAIRE

    Darren eBurke

    2014-01-01

    Despite a widespread acceptance that the brain that underpins human psychology is the result of biological evolution, very few psychologists in any way incorporate an evolutionary perspective in their research or practice. There have been many attempts to convince mainstream psychology of the importance of such a perspective, mostly from those who identify with Evolutionary Psychology, and there has certainly been progress in that direction, but the core of psychology remains essentially unev...

  11. The Globalisation of Firms as a Social Evolutionary Process

    OpenAIRE

    Thomas Borghoff

    2011-01-01

    From a social systems theory perspective, globalisation can be conceptualised as an evolutionary social process. By fusing systems theories, evolutionary theories, and organisation theories, globalisation becomes apparent as a historical social process, which encompasses the emergence and reproduction of social systems such as firms or other organisations within the wider process of the globalisation of society. The conceptualisation of firms as social systems also opens new perspectives on m...

  12. Perspectiva evolucionária na teoria social crítica de Habermas The evolutionary perspective in Habermas' critical social theory

    Directory of Open Access Journals (Sweden)

    Clodomiro José Bannwart Júnior

    2013-01-01

    Full Text Available Busca-se acompanhar o desenvolvimento da teoria evolucionária no pensamento de Habermas, a partir da afirmação colhida no prólogo de Problemas de Legitimação do Capitalismo Tardio, de 1973: "O caráter programático evidencia que uma teoria da evolução social hoje se encontra apenas esboçada, mas que, no entanto, deveria constituir a base da teoria da sociedade". A atenção é direcionada à forma como Habermas reorienta o sentido evolucionário do desdobramento histórico à luz do conceito de mundo da vida, como esfera de realização da ação comunicativa. Objetiva-se investigar como é projetada nesse modelo de ação, por meio da linguagem, a tarefa de produção e reprodução simbólica do consenso normativo entre os participantes do mundo social, ao mesmo tempo em que Habermas sinaliza haver um telos de integração social imanente à própria prática comunicativa. Nesse sentido, procurar-se-á demonstrar que, assim como a pragmática universal serve de base teórica para a análise de processos de distorção da linguagem e de socialização anormais, a teoria da evolução social serve de parâmetro para uma teoria social crítica com intenção emancipatória de avaliar o desdobramento empírico e contingente da dinâmica histórica.We seek to follow the development of evolutionary theory in the thought of Habermas, starting with the statement taken from the Prologue of Legitimation Crisis, 1973: "The programmatic character of Part I of this book makes clear that a theory of social evolution, although it must be the basis of social theory, is today still scarcely at all developed." Attention is directed to how Habermas reorients the evolutionary meaning of historical development in light of the concept of lifeworld as the sphere of the realization of communicative action. We seek to investigate how Habermas' model assigns, by means of language, the task of symbolic production and reproduction of the normative consensus

  13. An Evolutionary Perspective on Friendship and Happiness%进化心理学视角下的友谊与幸福感

    Institute of Scientific and Technical Information of China (English)

    林雪; 周铁民

    2016-01-01

    The pursuit of friendship seems to be an instinct of human which is a important binary relation of social life. In the process of establishing and maintaining friendship,individuals cost energy,gain support,avoid loneliness and Improve personal happiness. In the view of Evolutionary,primitive human gain a series of adaptive benefit from friendship and make it become a kind of psychological mechanism under the effect of natural selection. Understanding the forming process of the mechanism,exploring strategies of how friendship maximize benefit and minimize the cost have important significance for ascending human happiness and well-being.%追求友谊这种社会生活中的重要二元关系仿佛是人类生而具有的本能,在建立与维持友谊的过程中个体付出精力,收获支持、避免孤独、幸福感得到提升。进化观中原始人类从友谊中获得一系列适应性利益而使其在自然选择下成为一种心理机制,了解这一机制的形成过程并探究友谊交往中利益最大化、代价最小化的策略,对提升人类与个体幸福感有着重要意义。

  14. Assessment of student conceptions of evolutionary trees

    Science.gov (United States)

    Blacquiere, Luke

    Biologists use evolutionary trees to depict hypotheses about the relationships among taxa. Trees possess lines that represent lineages, internal nodes that represent where lineages become evolutionarily isolated from one another and terminal nodes that represent the taxa under consideration. Interpreting a tree (i.e., "tree-thinking") is an important skill for biologists yet many students struggle when reading evolutionary trees. Common documented misconceptions include using morphological similarity, internal node counting or terminal node proximity, instead of identifying the internal node that represents a most recent common ancestor (MRCA), to determine relationships among taxa. I developed an instrument to assess whether students were using common ancestry or another, non-scientific, strategy to determine relationships among taxa. The study is the first to explicitly test hypotheses about how students approach reading evolutionary trees. To test the hypotheses an instrument was developed. The instrument is the first reliable and valid assessment testing student understanding of how to use most recent common ancestor to interpret evolutionary relationships in tree diagrams. Instructors can use the instrument as a diagnostic tool enabling them to help students learn this challenging concept. This study shows that, contrary to the assertion that students hold misconceptions about evolutionary trees made in the literature, students do not consistently use erroneous strategies when interpreting trees. This study suggests that a constructivist perspective of cognitive structure describes students' conception of evolutionary trees more closely than a misconception perspective.

  15. 以演化经济学视角探讨企业文化建设%To Explore the Corporate Culture Construction from the Perspective of Evolutionary Economics

    Institute of Scientific and Technical Information of China (English)

    赵建生; 冯丽轩

    2013-01-01

    笔者从演化经济学角度对企业文化演化过程进行分析,认为企业文化是一个不断进行“遗传—变异—选择—保留”的螺旋上升过程,企业文化的演化与企业结构、技术、目标演化存在协同关系.从这一结论出发,结合企业演化过程中的诸多影响因素,对企业文化建设提出建议.%The author analyzes the evolution of corporate culture from the perspective of evolutionary economics, thinks the enterprise culture is an ongoing "genetic-variation-choice-keep" spiral process, enterprise culture evolution and enterprise structure, technological evolution, objectives are in collaborative relationship. From this conclusion, combined with many influence factors in the evolution process of enterprise, and makes some suggestions to the corporate culture construction.

  16. Reconstruction of Adam Smith's Theory of Economic Development under the Evolutionary Perspective%演化视角下亚当·斯密经济发展理论的重构

    Institute of Scientific and Technical Information of China (English)

    戴玲; 张卫

    2015-01-01

    Adam Smith's theory of economic development connotation is rich. "Back to Adam Smith," rethink Smith's theory of development is of great significance for understanding economic development and China's Reform and opening up. The in-novation of this paper is to reconstruct Smith's theory of economic development under the perspective of evolutionary eco-nomics; his development theory is a institution, the division of labor and capital accumulation spiral co-evolution based on the organic evolution of the dynamic system.%斯密的经济发展学说内涵丰富。“回到亚当·斯密”,重新思索斯密的发展学说对于理解经济发展乃至中国的改革开放具有重要意义。本文从演化经济学的视角重构了斯密的经济发展学说,认为其发展理论是以制度、劳动分工、资本积累三者螺旋式协同演化为基础的动态有机演化系统。

  17. The Micro Evolutionary Mechanism Analysis of Organization Learning Based on the Perspective of Reciprocal Reference%基于互惠性行为视角的组织学习微观演化机理解析

    Institute of Scientific and Technical Information of China (English)

    刘良灿; 张同建; 林昭文

    2011-01-01

    组织学习微观机理的研究是组织学习体系的一个薄弱环节,而个体之间的学习是组织学习微观机理解析的契入点.基于互惠性学习行为的视角,个体之间学习的演化博弈分析可以为组织学习的动态性演化提供合理的解释,揭示互惠性环境下组织学习的微观运作机制,从而弥补组织学习体系研究的不足,为组织学习的深入开展提供有效的理论借鉴.%The microscopic mechanism research is a weak link of organizational learning, and the learning between individuals is the key point of micro organization learning study.Based on the perspective of reciprocal learning, the evolutionary game analysis between individuals may provide reasonable explanation for dynamics of organization learning, and reveal the micro mechanism of organization learning under reciprocal environment, which may make up the insufficiency of organization learning and provide effective theory reference for organization learning.

  18. Evolutionary Psychology: Controversies, Questions, Prospects, and Limitations

    Science.gov (United States)

    Confer, Jaime C.; Easton, Judith A.; Fleischman, Diana S.; Goetz, Cari D.; Lewis, David M. G.; Perilloux, Carin; Buss, David M.

    2010-01-01

    Evolutionary psychology has emerged over the past 15 years as a major theoretical perspective, generating an increasing volume of empirical studies and assuming a larger presence within psychological science. At the same time, it has generated critiques and remains controversial among some psychologists. Some of the controversy stems from…

  19. [Evolutionary medicine: an emergent basic science].

    Science.gov (United States)

    Spotorno, Angel E

    2005-02-01

    Evolutionary Medicine is an emergent basic science that offers new and varied perspectives to the comprehension of human health. The application of classic evolutionary theories (descent with modification, and natural selection) to the human organism, to its pathogens, and their mutual co-evolution, provides new explanations about why we get sick, how we can prevent this, and how we can heal. Medicine has focused mainly on the proximate or immediate causes of diseases and the treatment of symptoms, and very little on its evolutionary or mediate causes. For instance, the present human genome and phenotypes are essentially paleolithic ones: they are not adapted to modern life style, thus favoring the so-called diseases of civilization (ie: ateroesclerosis, senescence, myopia, phobias, panic attacks, stress, reproductive cancers). With the evolutionary approach, post-modern medicine is detecting better the vulnerabilities, restrictions, biases, adaptations and maladaptations of human body, its actual diseases, and its preventions.

  20. Evolutionary robotics: model or design?

    OpenAIRE

    Trianni, Vito

    2014-01-01

    In this paper, I review recent work in evolutionary robotics (ER), and discuss the perspectives and future directions of the field. First, I propose to draw a crisp distinction between studies that exploit ER as a design methodology on the one hand, and studies that instead use ER as a modeling tool to better understand phenomena observed in biology. Such a distinction is not always that obvious in the literature, however. It is my conviction that ER would profit from an explicit commitment t...

  1. Metaphylogeny of 82 gene families sheds a new light on chordate evolution

    OpenAIRE

    Vienne, Alexandre; Pontarotti, Pierre

    2006-01-01

    Achieving a better comprehension of the evolution of species has always been an important matter for evolutionary biologists. The deuterostome phylogeny has been described for many years, and three phyla are distinguishable: Echinodermata (including sea stars, sea urchins, etc…), Hemichordata (including acorn worms and pterobranchs), and Chordata (including urochordates, cephalochordates and extant vertebrates). Inside the Chordata phylum, the position of vertebrate species is quite unanimous...

  2. Developmental Control of Cell-Cycle Compensation Provides a Switch for Patterned Mitosis at the Onset of Chordate Neurulation.

    Science.gov (United States)

    Ogura, Yosuke; Sasakura, Yasunori

    2016-04-18

    During neurulation of chordate ascidians, the 11th mitotic division within the epidermal layer shows a posterior-to-anterior wave that is precisely coordinated with the unidirectional progression of the morphogenetic movement. Here we show that the first sign of this patterned mitosis is an asynchronous anterior-to-posterior S-phase length and that mitotic synchrony is reestablished by a compensatory asynchronous G2-phase length. Live imaging combined with genetic experiments demonstrated that compensatory G2-phase regulation requires transcriptional activation of the G2/M regulator cdc25 by the patterning genes GATA and AP-2. The downregulation of GATA and AP-2 at the onset of neurulation leads to loss of compensatory G2-phase regulation and promotes the transition to patterned mitosis. We propose that such developmentally regulated cell-cycle compensation provides an abrupt switch to spatially patterned mitosis in order to achieve the coordination between mitotic timing and morphogenesis.

  3. 进化生物学视角下的创意企业 R & D 能力演化%Evolution of R & D Ability in Creative Enterprises from Perspective of Evolutionary Biology

    Institute of Scientific and Technical Information of China (English)

    刘冰峰; 闫宁宁

    2015-01-01

    针对不同的创意企业R&D活动在规模、技术、文化及生存环境等方面存在的显著差别,从达尔文进化论到中性突变论、超循环论等进化生物学的理论视角出发,探讨了创意企业R&D能力演化的超循环机制,分析了创意企业R&D能力的自我进化博弈。研究表明,市场机会的开拓和挖掘、产品的研制和生产及R&D人才的引进和培养三者构成了创意企业R&D能力的超循环;R&D参与者初始实力的高低对R&D能力的演化没有太大影响,需要企业主动推动R&D能力的有效进化。%Significant difference of different creative enterprises ’ R&D activity in scale, technology, culture, and existing environment was discussed .From the research perspective of Darwin's evolution theory , neutral mutation theory , super cycle the-ory and many other evolutionary biology theories , the super cycle mechanism of R&D ability evolution in creative enterprises was investigated .The self-evolutionary game of R&D ability in creative enterprises was analyzed .Research result shows that the su-per cycle of creative enterprises ’ R&D ability includes the market opportunities open up and mining , product development and production, introduction and cultivation of R&D talent;the initial strength level of R&D participants has not significant effect on R&D ability evolution;it requires enterprises actively promote the effective evolution of R&D ability .

  4. Entrepreneurs and Evolutionary Biology: The Relationship between Testosterone and New Venture Creation

    Science.gov (United States)

    White, Roderick E.; Thornhill, Stewart; Hampson, Elizabeth

    2006-01-01

    Biological evolutionary processes select for heritable behaviors providing a survival and reproductive advantage. Accordingly, how we behave is, at least in part, affected by the evolutionary history of our species. This research uses evolutionary psychology as the theoretical perspective for exploring the relationship between a heritable…

  5. Why isn’t everyone an Evolutionary Psychologist?

    Directory of Open Access Journals (Sweden)

    Darren eBurke

    2014-08-01

    Full Text Available Despite a widespread acceptance that the brain that underpins human psychology is the result of biological evolution, very few psychologists in any way incorporate an evolutionary perspective in their research or practice. There have been many attempts to convince mainstream psychology of the importance of such a perspective, mostly from those who identify with Evolutionary Psychology, and there has certainly been progress in that direction, but the core of psychology remains essentially unevolutionary. Here I explore a number of potential reasons for mainstream psychology continuing to ignore or resist an evolutionary approach, and suggest some ways in which those of us interested in seeing an increase in the proportion of psychologists adopting an evolutionary perspective might need to modify our tactics to increase our chances of success.

  6. Consideration of Higher Sex Ratio From the Perspective of Evolutionary Psychology%性别比偏高的后果:进化心理学视角下的分析

    Institute of Scientific and Technical Information of China (English)

    王瑞乐

    2012-01-01

      出生人口性别比偏高已经成为威胁我国人口安全的主要问题之一。国内学者对性别比偏高后果的分析多为描述性,尽管国外研究者对此进行了大量的实证研究,但是否适合我国人口基数大、性别比失衡严重的国情尚不明确。试从进化心理学视角出发,结合国外已有研究成果,来分析性别比失衡对个体择偶心理的影响,进而分析其可能引发的婚姻家庭、违法犯罪、经济行为后果,以期为政策制定提供科学依据,并为未来研究指出方向。%  High sex ratio of births in China has become a threat to China 's population security.The domestic scholars’ a-nalysis on the consequence of higher sex ratio was descriptive .Although foreign researchers have conducted a lot of empirical studies, but it’s still not clear whether these results are suitable for the actual conditions of China which has a large population base and a serious sex ratio imbalance .From an evolutionary psychological perspective and the existing studies , this article dis-cussed the effect of Chinese sex ratio imbalance on the individual mating psychology , and then analyzed the possible family , so-cial, and economic consequences caused by the sex ratio imbalance in order to help future research and government policy mak -ing.

  7. The evolutionary history of mitochondrial porins

    Directory of Open Access Journals (Sweden)

    Hausner Georg

    2007-02-01

    Full Text Available Abstract Background Mitochondrial porins, or voltage-dependent anion-selective channels (VDAC allow the passage of small molecules across the mitochondrial outer membrane, and are involved in complex interactions regulating organellar and cellular metabolism. Numerous organisms possess multiple porin isoforms, and initial studies indicated an intriguing evolutionary history for these proteins and the genes that encode them. Results In this work, the wealth of recent sequence information was used to perform a comprehensive analysis of the evolutionary history of mitochondrial porins. Fungal porin sequences were well represented, and newly-released sequences from stramenopiles, alveolates, and seed and flowering plants were analyzed. A combination of Neighbour-Joining and Bayesian methods was used to determine phylogenetic relationships among the proteins. The aligned sequences were also used to reassess the validity of previously described eukaryotic porin motifs and to search for signature sequences characteristic of VDACs from plants, animals and fungi. Secondary structure predictions were performed on the aligned VDAC primary sequences and were used to evaluate the sites of intron insertion in a representative set of the corresponding VDAC genes. Conclusion Our phylogenetic analysis clearly shows that paralogs have appeared several times during the evolution of VDACs from the plants, metazoans, and even the fungi, suggesting that there are no "ancient" paralogs within the gene family. Sequence motifs characteristic of the members of the crown groups of organisms were identified. Secondary structure predictions suggest a common 16 β-strand framework for the transmembrane arrangement of all porin isoforms. The GLK (and homologous or analogous motifs and the eukaryotic porin motifs in the four representative Chordates tend to be in exons that appear to have changed little during the evolution of these metazoans. In fact there is phase

  8. Evolutionary cell biology: two origins, one objective.

    Science.gov (United States)

    Lynch, Michael; Field, Mark C; Goodson, Holly V; Malik, Harmit S; Pereira-Leal, José B; Roos, David S; Turkewitz, Aaron P; Sazer, Shelley

    2014-12-01

    All aspects of biological diversification ultimately trace to evolutionary modifications at the cellular level. This central role of cells frames the basic questions as to how cells work and how cells come to be the way they are. Although these two lines of inquiry lie respectively within the traditional provenance of cell biology and evolutionary biology, a comprehensive synthesis of evolutionary and cell-biological thinking is lacking. We define evolutionary cell biology as the fusion of these two eponymous fields with the theoretical and quantitative branches of biochemistry, biophysics, and population genetics. The key goals are to develop a mechanistic understanding of general evolutionary processes, while specifically infusing cell biology with an evolutionary perspective. The full development of this interdisciplinary field has the potential to solve numerous problems in diverse areas of biology, including the degree to which selection, effectively neutral processes, historical contingencies, and/or constraints at the chemical and biophysical levels dictate patterns of variation for intracellular features. These problems can now be examined at both the within- and among-species levels, with single-cell methodologies even allowing quantification of variation within genotypes. Some results from this emerging field have already had a substantial impact on cell biology, and future findings will significantly influence applications in agriculture, medicine, environmental science, and synthetic biology. PMID:25404324

  9. Evolutionary cell biology: two origins, one objective.

    Science.gov (United States)

    Lynch, Michael; Field, Mark C; Goodson, Holly V; Malik, Harmit S; Pereira-Leal, José B; Roos, David S; Turkewitz, Aaron P; Sazer, Shelley

    2014-12-01

    All aspects of biological diversification ultimately trace to evolutionary modifications at the cellular level. This central role of cells frames the basic questions as to how cells work and how cells come to be the way they are. Although these two lines of inquiry lie respectively within the traditional provenance of cell biology and evolutionary biology, a comprehensive synthesis of evolutionary and cell-biological thinking is lacking. We define evolutionary cell biology as the fusion of these two eponymous fields with the theoretical and quantitative branches of biochemistry, biophysics, and population genetics. The key goals are to develop a mechanistic understanding of general evolutionary processes, while specifically infusing cell biology with an evolutionary perspective. The full development of this interdisciplinary field has the potential to solve numerous problems in diverse areas of biology, including the degree to which selection, effectively neutral processes, historical contingencies, and/or constraints at the chemical and biophysical levels dictate patterns of variation for intracellular features. These problems can now be examined at both the within- and among-species levels, with single-cell methodologies even allowing quantification of variation within genotypes. Some results from this emerging field have already had a substantial impact on cell biology, and future findings will significantly influence applications in agriculture, medicine, environmental science, and synthetic biology.

  10. Aminoacyl-tRNA Synthetases, the Genetic Code, and the Evolutionary Process

    OpenAIRE

    Woese, Carl R.; Olsen, Gary J; Ibba, Michael; Söll, Dieter

    2000-01-01

    The aminoacyl-tRNA synthetases (AARSs) and their relationship to the genetic code are examined from the evolutionary perspective. Despite a loose correlation between codon assignments and AARS evolutionary relationships, the code is far too highly structured to have been ordered merely through the evolutionary wanderings of these enzymes. Nevertheless, the AARSs are very informative about the evolutionary process. Examination of the phylogenetic trees for each of the AARSs reveals the followi...

  11. The Evolutionary Psychology of Psychopathology: Towards an Integrative Conceptual Framework and Research Programme

    OpenAIRE

    Kennair, Leif Edward Ottesen

    2008-01-01

    Evolutionary Psychology is a potentially unifying research program for evolutionary studies of psychopathology: Evolutionary Psychopathology. Although there are many competing research programs and researchers who study human or other animals’ minds or behaviour from an evolutionary perspective, these have a fundamental weakness in their reduced potential to aid accumulative theory building, due to the many diverging approaches, subtheories, and lack of overarching meta-theory. Most research ...

  12. Evolutionary Explanation of Psychopaths

    OpenAIRE

    Seungbae Park

    2013-01-01

    Psychopaths are brutal individuals, having no empathetic concern for others. Initially, the existence of psychopaths seems to be a mystery from an evolutionary point of view. On close examination, however, it can be accommodated by evolutionary theory. Brutal individuals excelled meek individuals in the desperate circumstances where they had to fight their competitors over natural resources for survival and reproduction. This evolutionary explanation of psychopaths receives support from Pinke...

  13. Remembering the evolutionary Freud.

    Science.gov (United States)

    Young, Allan

    2006-03-01

    Throughout his career as a writer, Sigmund Freud maintained an interest in the evolutionary origins of the human mind and its neurotic and psychotic disorders. In common with many writers then and now, he believed that the evolutionary past is conserved in the mind and the brain. Today the "evolutionary Freud" is nearly forgotten. Even among Freudians, he is regarded to be a red herring, relevant only to the extent that he diverts attention from the enduring achievements of the authentic Freud. There are three ways to explain these attitudes. First, the evolutionary Freud's key work is the "Overview of the Transference Neurosis" (1915). But it was published at an inopportune moment, forty years after the author's death, during the so-called "Freud wars." Second, Freud eventually lost interest in the "Overview" and the prospect of a comprehensive evolutionary theory of psychopathology. The publication of The Ego and the Id (1923), introducing Freud's structural theory of the psyche, marked the point of no return. Finally, Freud's evolutionary theory is simply not credible. It is based on just-so stories and a thoroughly discredited evolutionary mechanism, Lamarckian use-inheritance. Explanations one and two are probably correct but also uninteresting. Explanation number three assumes that there is a fundamental difference between Freud's evolutionary narratives (not credible) and the evolutionary accounts of psychopathology that currently circulate in psychiatry and mainstream journals (credible). The assumption is mistaken but worth investigating.

  14. Communicating Climate Change: An Evolutionary Perspective

    Science.gov (United States)

    Peacock, K. A.; Byrne, J. M.; McDaniel, S.

    2012-12-01

    The most effective way to communicate the scientific "big picture" is to appeal to the intelligence and imagination of that large number of people who really want to know what science has to say, and who really would be likely to support enlightened policies if they were given an unflinching picture of the present human predicament. Staff writers at Life Magazine used to be told, "Never overestimate readers' information; never underestimate their intelligence." In the long run, whatever communications channels may be employed, the best hope of moving forward is to appeal to the intelligence of the public. (Media such as wikis, which invite participation, could be one of the best ways to do that.) There are two salient "big picture" facts to be communicated. The first is the ecological unsustainability of the present human condition. There is not the slightest possibility of a long-term future for a planetary-scale, technologically-intensive society of over 7 billion talking hominids that gets most of its free energy from the combustion of a one-time-only store of biotic waste products laid down in the strata hundreds of millions of years ago. Not only is this limited fuel supply running out, but its waste products are rapidly destabilizing the very climatic conditions that favoured the growth of our complex culture. As Homer-Dixon puts it, we are on the "cusp of a planetary-scale emergency"—obvious to earth scientists, but not obvious to all of even the best-intentioned members of the public. The second crucial fact is that our species' capacity to innovate (technologically, linguistically, socially), unique in the history of life on this planet, has up to now been our most effective survival tool and still remains our best chance for pulling through the present crisis. Herbert Spencer said that the most important adaptive trait is what he called "sagacity"—intelligent adaptability. But our sagacity now faces its toughest test, tougher than the harsh Ice Age in which it was honed. We were clever enough to figure out how to tap into the rich supply of carbon-based fuels left us by the prolific Paleozoic. The question now is whether we are sagacious enough to find way of keeping the lights on that does not undermine the very ecological conditions that made our evolution possible. There will be no miracles, except the miracle of human creativity itself, but this could be miracle enough for the very nature of creativity is solve problems by stepping outside assumed parameters. Innovation can't be managed but it can be fostered like any other evolved human capacity. Above all else we need to give human ingenuity room and means to operate. This is far more important than advocating any particular solutions that currently present themselves (though that should be done, too). We have to talk openly about the barriers to innovation such as vested interests (corporate, academic, political), entrenched assumptions and conceptual blockages of many sorts, and the near-total lack of mechanisms for financing the social and technological innovations we need. People need to be reminded again and again that those past cultures which survived ecological upheavals were the ones willing to tolerate change. In sum: the most salient thing to communicate is the need for ingenuity in fostering ingenuity.

  15. Evolutionary Perspectives on Language and Brain Plasticity.

    Science.gov (United States)

    Deacon, Terrence W.

    2000-01-01

    This review discusses how general principles of brain development have contributed to both human brain plasticity and the acquisition of the human capacity for speech. Specifically, the role played by plastic developmental processes in the evolution and development of articulate control over vocalization in speech is examined. (Contains…

  16. Human altruism from an evolutionary perspective

    NARCIS (Netherlands)

    Fetchenhauer, D; Bierhoff, HW

    2004-01-01

    According to Darwin's theory of evolution by natural selection altruistic behavior appears to be a paradox. Because altruistic behaviors are defined as acts of transferring resources to another person without getting any resources back (at least in the short run) it could be argued that any altruist

  17. Evolutionary Perspectives on Myrmecophily in Ladybirds

    Directory of Open Access Journals (Sweden)

    Amélie Vantaux

    2012-01-01

    Full Text Available Myrmecophiles are species that usually have developed specialized traits to cope with the aggressiveness of ants enabling them to live in their vicinity. Many coccinellid species are predators of Hemiptera; the latter is also often protected by ants. Therefore these ladybirds frequently interact with ants, and some species have become myrmecophilous. In this paper, we aim to provide an overview of the evolution of myrmecophilous traits in ladybirds. We then discuss the costs and benefits of myrmecophily and the dietary shift to myrmecophagy observed in a few species.

  18. Evolutionary perspectives on human height variation

    NARCIS (Netherlands)

    Stulp, Gert; Barrett, Louise

    2016-01-01

    Human height is a highly variable trait, both within and between populations, has a high heritability, and influences the manner in which people behave and are treated in society. Although we know much about human height, this information has rarely been brought together in a comprehensive, systemat

  19. The acquisition of myelin: An evolutionary perspective.

    Science.gov (United States)

    Zalc, B

    2016-06-15

    It has been postulated that the emergence of vertebrates was made possible by the acquisition of neural crest cells, which then led to the development of evolutionarily advantageous complex head structures (Gans and Northcutt, 1983). In this regard the contribution of one important neural crest derivative-the peripheral myelin sheath-to the success of the vertebrates has to be pointed out. Without this structure, the vertebrates, as we know them, simply could not exist. After briefly reviewing the major functions of the myelin sheath we will ask and provide tentative answers to the following three questions: when during evolution has myelin first appeared? Where has myelin initially appeared: in the CNS or in the PNS? Was it necessary to acquire a new cell type to form a myelin sheath? Careful examination of fossils lead us to conclude that myelin was acquired 425 MY ago by placoderms, the earliest hinge-jaw fishes. I argue that the acquisition of myelin during evolution has been a necessary prerequisite to permit gigantism of gnathostome species, including the sauropods. I propose that this acquisition occurred simultaneously in the PNS and CNS and that myelin forming cells are the descendants of ensheathing glia, already present in invertebrates, that have adapted their potential to synthesize large amount of membrane in response to axonal requirements. This article is part of a Special Issue entitled SI: Myelin Evolution. PMID:26367449

  20. An Evolutionary Perspective of Friendship Selection

    Science.gov (United States)

    Coutinho, Savia A.

    2007-01-01

    The research reported in this article investigates whether promiscuity plays a role in same-sex and opposite-sex friend selection. Since same-sex friends share strong similarity and spend time with their friends' mates or potential mates, it becomes important to select same-sex friends who will not be sexual rivals. One way to determine rivalry in…

  1. The Pleiomorphic Plant MTOC: An Evolutionary Perspective

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    γ-Tubulin is an essential component of the microtubule organizing center (MTOC) responsible for nucleating microtubules In both plants and animals. Whereas γ-tubulin is tightly associated with centrosomes that are inheritable organelles in cells of animals and most algae, it appears at different times and places to organize the myriad specialized microtubule systems that characterize plant cells. We have traced the distribution of γ-tubulin through the cell cycle in representative land plants (embryophytes) and herein present data that have led to a concept of the pleiomorphic and migratory MTOC.The many forms of the plant MTOC at spindle organization constitute pleiomorphism, and stage-specific "migration" is suggested by the consistent pattern of redistribution of γ-tubulin during mitosis. Mitotic spindles may be organized at centriolar centrosomes (only in final divisions of spermatogenesis), polar organizers (POs), plastid MTOCs, or nuclear envelope MTOCs (NE-MTOCs). In all cases, with the possible exception of centrosomes in spermatogenesis, the γ-tubulin migrates to broad polar regions and along the spindle fibers, even when it is initially a discrete polar entity. At anaphase it moves poleward, and subsequently migrates from polar regions (distal nuclear surfaces) into the interzone (proximal nuclear surfaces) where interzonal microtubule arrays and phragmoplasts are organized. Following cytokinesis, γ-tubulin becomes associated with nuclear envelopes and organizes radial microtubule systems (RMSs). These may exist only briefly, before establishment of hoop-like cortical arrays in vegetative tissues, or they may be characteristic of interphase in syncytial systems where they serve to organize the common cytoplasm into nuclear cytoplasmic domains (NCDs).

  2. The psychology of sharing: an evolutionary approach

    OpenAIRE

    Erdal, David Edward

    2000-01-01

    This thesis takes an evolutionary perspective on human psychology. To the extent that inherited tendencies shape behaviour, their design will be fitted to the social environments prevailing as Homo sapiens evolved, in foraging groups, the nearest modem equivalent being hunter-gatherers. From ethnographies of hunter-gatherers, food-sharing and counterdominance were identified as universal. Food-sharing was more thorough than is explicable purely by kinship or reciprocation; o...

  3. Virulence in malaria: an evolutionary viewpoint.

    OpenAIRE

    Margaret J Mackinnon; Andrew F Read

    2004-01-01

    Malaria parasites cause much morbidity and mortality to their human hosts. From our evolutionary perspective, this is because virulence is positively associated with parasite transmission rate. Natural selection therefore drives virulence upwards, but only to the point where the cost to transmission caused by host death begins to outweigh the transmission benefits. In this review, we summarize data from the laboratory rodent malaria model, Plasmodium chabaudi, and field data on the human mala...

  4. CiMT-1, an unusual chordate metallothionein gene in Ciona intestinalis genome: structure and expression studies.

    Science.gov (United States)

    Franchi, Nicola; Boldrin, Francesco; Ballarin, Loriano; Piccinni, Ester

    2011-02-01

    The present article reports on the characterization of the urochordate metallothionein (MT) gene, CiMT-1, from the solitary ascidian Ciona intestinalis. The predicted protein is shorter than other known deuterostome MTs, having only 39 amino acids. The gene has the same tripartite structure as vertebrate MTs, with some features resembling those of echinoderm MTs. The promoter region shows the canonical cis-acting elements recognized by transcription factors that respond to metal, ROS, and cytokines. Unusual sequences, described in fish and echinoderms, are also present. In situ hybridization suggests that only a population of hemocytes involved in immune responses, i.e. granular amebocytes, express CiMT-1 mRNA. These observations support the idea that urochordates perform detoxification through hemocytes, and that MTs may play important roles in inflammatory humoral responses in tunicates. The reported data offer new clues for better understanding the evolution of these multivalent proteins from non-vertebrate to vertebrate chordates and reinforce their functions in detoxification and immunity. PMID:21328559

  5. Evolutionary humanoid robotics

    CERN Document Server

    Eaton, Malachy

    2015-01-01

    This book examines how two distinct strands of research on autonomous robots, evolutionary robotics and humanoid robot research, are converging. The book will be valuable for researchers and postgraduate students working in the areas of evolutionary robotics and bio-inspired computing.

  6. Polymorphic Evolutionary Games.

    Science.gov (United States)

    Fishman, Michael A

    2016-06-01

    In this paper, I present an analytical framework for polymorphic evolutionary games suitable for explicitly modeling evolutionary processes in diploid populations with sexual reproduction. The principal aspect of the proposed approach is adding diploid genetics cum sexual recombination to a traditional evolutionary game, and switching from phenotypes to haplotypes as the new game׳s pure strategies. Here, the relevant pure strategy׳s payoffs derived by summing the payoffs of all the phenotypes capable of producing gametes containing that particular haplotype weighted by the pertinent probabilities. The resulting game is structurally identical to the familiar Evolutionary Games with non-linear pure strategy payoffs (Hofbauer and Sigmund, 1998. Cambridge University Press), and can be analyzed in terms of an established analytical framework for such games. And these results can be translated into the terms of genotypic, and whence, phenotypic evolutionary stability pertinent to the original game. PMID:27016340

  7. Evolutionary Origin of the Proepicardium

    Directory of Open Access Journals (Sweden)

    Elena Cano

    2013-05-01

    Full Text Available The embryonic epicardium and the cardiac mesenchyme derived from it are critical to heart development. The embryonic epicardium arises from an extracardiac progenitor tissue called the proepicardium, a proliferation of coelomic cells located at the limit between the liver and the sinus venosus. A proepicardium has not been described in invertebrates, and the evolutionary origin of this structure in vertebrates is unknown. We herein suggest that the proepicardium might be regarded as an evolutionary derivative from an ancient pronephric external glomerulus that has lost its excretory role. In fact, we previously described that the epicardium arises by cell migration from the primordia of the right pronephric external glomerulus in a representative of the most primitive vertebrate lineage, the lamprey Petromyzon marinus. In this review, we emphasize the striking similarities between the gene expression profiles of the proepicardium and the developing kidneys, as well as the parallelisms in the signaling mechanisms involved in both cases. We show some preliminary evidence about the existence of an inhibitory mechanism blocking glomerular differentiation in the proepicardium. We speculate as to the possibility that this developmental link between heart and kidney can be revealing a phylogenetically deeper association, supported by the existence of a heart-kidney complex in Hemichordates. Finally, we suggest that primitive hematopoiesis could be related with this heart-kidney complex, thus accounting for the current anatomical association of the hematopoietic stem cells with an aorta-gonad-mesonephros area. In summary, we think that our hypothesis can provide new perspectives on the evolutionary origin of the vertebrate heart.

  8. Evolutionary Studies in Business: A Presentation of a New Journal

    OpenAIRE

    Paloma Fernández Pérez; Jaume Valls Pasola

    2016-01-01

    The Journal of Evolutionary Studies in Business is a new open access journal led by an international interdisciplinary team of scholars located in eight institutions from three continents who wants to attract contributions that help shed light on the new questions, challenges, methodologies and realities, faced by businesses in an evolutionary perspective. The journal calls particularly for review essays that deal with new research topics about business, and provide useful overviews of the ke...

  9. The Evolution of Syntax: An Exaptationist Perspective

    OpenAIRE

    W. Tecumseh Fitch

    2011-01-01

    The evolution of language required elaboration of a number of independent mechanisms in the hominin lineage, including systems involved in signaling, semantics and syntax. Two perspectives on the evolution of syntax can be contrasted. The "continuist" perspective seeks the evolutionary roots of complex human syntax in simpler combinatory systems used in animal communication systems, such as iteration and sequencing. The "exaptationist" perspective posits evolutionary ch...

  10. The evolution and regulation of the mucosal immune complexity in the basal chordate amphioxus.

    Science.gov (United States)

    Huang, Shengfeng; Wang, Xin; Yan, Qingyu; Guo, Lei; Yuan, Shaochun; Huang, Guangrui; Huang, Huiqing; Li, Jun; Dong, Meiling; Chen, Shangwu; Xu, Anlong

    2011-02-15

    Both amphioxus and the sea urchin encode a complex innate immune gene repertoire in their genomes, but the composition and mechanisms of their innate immune systems, as well as the fundamental differences between two systems, remain largely unexplored. In this study, we dissect the mucosal immune complexity of amphioxus into different evolutionary-functional modes and regulatory patterns by integrating information from phylogenetic inferences, genome-wide digital expression profiles, time course expression dynamics, and functional analyses. With these rich data, we reconstruct several major immune subsystems in amphioxus and analyze their regulation during mucosal infection. These include the TNF/IL-1R network, TLR and NLR networks, complement system, apoptosis network, oxidative pathways, and other effector genes (e.g., peptidoglycan recognition proteins, Gram-negative binding proteins, and chitin-binding proteins). We show that beneath the superficial similarity to that of the sea urchin, the amphioxus innate system, despite preserving critical invertebrate components, is more similar to that of the vertebrates in terms of composition, expression regulation, and functional strategies. For example, major effectors in amphioxus gut mucous tissue are the well-developed complement and oxidative-burst systems, and the signaling network in amphioxus seems to emphasize signal transduction/modulation more than initiation. In conclusion, we suggest that the innate immune systems of amphioxus and the sea urchin are strategically different, possibly representing two successful cases among many expanded immune systems that arose at the age of the Cambrian explosion. We further suggest that the vertebrate innate immune system should be derived from one of these expanded systems, most likely from the same one that was shared by amphioxus. PMID:21248255

  11. Transmissible cancers in an evolutionary context.

    Science.gov (United States)

    Ujvari, Beata; Papenfuss, Anthony T; Belov, Katherine

    2016-07-01

    Cancer is an evolutionary and ecological process in which complex interactions between tumour cells and their environment share many similarities with organismal evolution. Tumour cells with highest adaptive potential have a selective advantage over less fit cells. Naturally occurring transmissible cancers provide an ideal model system for investigating the evolutionary arms race between cancer cells and their surrounding micro-environment and macro-environment. However, the evolutionary landscapes in which contagious cancers reside have not been subjected to comprehensive investigation. Here, we provide a multifocal analysis of transmissible tumour progression and discuss the selection forces that shape it. We demonstrate that transmissible cancers adapt to both their micro-environment and macro-environment, and evolutionary theories applied to organisms are also relevant to these unique diseases. The three naturally occurring transmissible cancers, canine transmissible venereal tumour (CTVT) and Tasmanian devil facial tumour disease (DFTD) and the recently discovered clam leukaemia, exhibit different evolutionary phases: (i) CTVT, the oldest naturally occurring cell line is remarkably stable; (ii) DFTD exhibits the signs of stepwise cancer evolution; and (iii) clam leukaemia shows genetic instability. While all three contagious cancers carry the signature of ongoing and fairly recent adaptations to selective forces, CTVT appears to have reached an evolutionary stalemate with its host, while DFTD and the clam leukaemia appear to be still at a more dynamic phase of their evolution. Parallel investigation of contagious cancer genomes and transcriptomes and of their micro-environment and macro-environment could shed light on the selective forces shaping tumour development at different time points: during the progressive phase and at the endpoint. A greater understanding of transmissible cancers from an evolutionary ecology perspective will provide novel avenues for

  12. Evolutionary history of the iroquois/Irx genes in metazoans

    Directory of Open Access Journals (Sweden)

    Ikmi Aissam

    2009-04-01

    Full Text Available Abstract Background The iroquois (iro/Irx genes encode transcriptional regulators that belong to the TALE superclass of homeodomain proteins and have key functions during development in both vertebrates and insects. The Irx genes occur in one or two genomic clusters containing three genes each within the Drosophila and several vertebrate genomes, respectively. The similar genomic organization in Drosophila and vertebrates is widely considered as a result of convergent evolution, due to independent tandem gene duplications. In this study, we investigate the evolutionary history of the Irx genes at the scale of the whole metazoan kingdom. Results We identified in silico the putative full complement of Irx genes in the sequenced genomes of 36 different species representative of the main metazoan lineages, including non bilaterian species, several arthropods, non vertebrate chordates, and a basal vertebrate, the sea lamprey. We performed extensive phylogenetic analyses of the identified Irx genes and defined their genomic organizations. We found that, in most species, there are several Irx genes, these genes form two to four gene clusters, and the Irx genes are physically linked to a structurally and functionally unrelated gene known as CG10632 in Drosophila. Conclusion Three main conclusions can be drawn from our study. First, an Irx cluster composed of two genes, araucan/caupolican and mirror, is ancestral to the crustaceans+insects clade and has been strongly conserved in this clade. Second, three Irx genes were probably present in the last common ancestor of vertebrates and the duplication that has given rise to the six genes organized into two clusters found in most vertebrates, likely occurred in the gnathostome lineage after its separation from sea lampreys. Third, the clustered organization of the Irx genes in various evolutionary lineages may represent an exceptional case of convergent evolution or may point to the existence of an Irx gene

  13. When development matters: From evolutionary psychology to evolutionary developmental psychology

    OpenAIRE

    Hernández Blasi, Carlos; Bjorklund, David F.; Gardiner, Amy K.

    2008-01-01

    This article presents evolutionary developmental psychology (EDP) as an emerging field of evolutionary psychology (EP). In describing the core tenets of both approaches and the differences between them, we emphasize the important roles that evolution and development have in understanding human behaviour. We suggest that developmental psychologists should pay more attention to evolutionary issues and, conversely, evolutionary psychologists should take development seriously ...

  14. Evolutionary Theorizing in Economics

    OpenAIRE

    Richard R. Nelson; Winter, Sidney G.

    2002-01-01

    This paper reviews the case for an evolutionary approach to problems of economic analysis, ranging from the details of individual firm behavior in the short run through industrial dynamics to the historical evolution of institutions and technologies. We draw upon a substantial body of recent research contributions. We characterize micro behavior as governed by skills and routines that are shaped by learning and selection. We then consider major areas of application of evolutionary thinking, i...

  15. Music and evolutionary computation

    OpenAIRE

    Reis, Cecília; Marques, Viriato M.; Machado, J. A. Tenreiro

    2011-01-01

    This paper presents a brief history of the western music: from its genesis to serialism and the Darmstadt school. Also some mathematical aspects of music are then presented and confronted with music as a form of art. The question is, are these two distinct aspects compatible? Can computers be of real help in automatic composition? The more appealing algorithmic approach is evolutionary computation as it offers creativity potential. Therefore, the Evolutionary Algorithms are then introduced an...

  16. Assédio moral: análise de conceito na perspectiva evolucionista de Rodgers Acoso moral: análisis de concepto en la perspectiva evolucionista de Rodgers Bullying: concept analysis from Rodgers' evolutionary perspective

    Directory of Open Access Journals (Sweden)

    Graziela Ribeiro Pontes Cahú

    2012-01-01

    destacaron los problemas psicosomáticos, empresariales y sociales. En este sentido, el concepto acoso moral se constituye en violencia psicológica con la intención de humillar y excluir socialmente a la víctima, provocando disturbios psicosomáticos, perjuicios a la sociedad y a la institución de trabajo.The study aimed to analyze the concept of bullying from Rodgers' evolutionary perspective, as expressed in the health, legal sciences, social and humanities literature. This was document research, which had for sources of data the articles available in the Periodical Portal / CAPES and Buscalegis from 1954 to 2010. The sample consisted of 46 items. For data analysis, we used the steps proposed by Rodgers in her model of conceptual analysis. In relation to the surrogate/related terms, we discovered psychoterror and mobbing. As for attributes, the most frequently understood were psychological violence and the social exclusion of the worker. The most relevant antecedents were the oppressive conditions of work. Regarding consequences, the highlights were psychosomatic, business and social problems. In this sense, the concept of bullying constitutes psychological violence with the intent to humiliate and socially exclude the victim, provoking psychosomatic disorders, impairing society and the workplace institution.

  17. Photoresponse and Learning Behavior of Ascidian Larvae, a Primitive Chordate, to Repeated Stimuli of Step-Up and Step-Down of Light

    OpenAIRE

    Kawakami, I.; Shiraishi, S; Tsuda, M

    2002-01-01

    Ascidians are lower chordates and their simple tadpole-like larvae share a basic body plan with vertebrates. Newly hatched larvae show no response to a stimulus of light. 4 h after hatching, the larvae were induced to swim upon a step-down of light and stop swimming upon a step-up of light. At weaker intensity of light, the larvae show the same response to a stimulus after presentation of repeated stimuli. When intensity of actinic light was increased, the larvae show sensitization and habitu...

  18. Pax2/5/8 and Pax6 alternative splicing events in basal chordates and vertebrates: a focus on paired box domain

    OpenAIRE

    Fabian, Peter; Kozmikova, Iryna; Kozmik, Zbynek; Pantzartzi, Chrysoula N.

    2015-01-01

    Paired box transcription factors play important role in development and tissue morphogenesis. The number of Pax homologs varies among species studied so far, due to genome and gene duplications that have affected PAX family to a great extent. Based on sequence similarity and functional domains, four Pax classes have been identified in chordates, namely Pax1/9, Pax2/5/8, Pax3/7, and Pax4/6. Numerous splicing events have been reported mainly for Pax2/5/8 and Pax6 genes. Of significant interest ...

  19. From computers to cultivation: reconceptualizing evolutionary psychology

    Directory of Open Access Journals (Sweden)

    Louise eBarrett

    2014-08-01

    Full Text Available Does evolutionary theorizing have a role in psychology? This is a more contentious issue than one might imagine, given that as evolved creatures, the answer must surely be yes. The contested nature of evolutionary psychology lies not in our status as evolved beings, but in the extent to which evolutionary ideas add value to studies of human behaviour, and the rigour with which these ideas are tested. This, in turn, is linked to the framework in which particular evolutionary ideas are situated. While the framing of the current research topic places the brain-as-computer metaphor in opposition to evolutionary psychology, the most prominent school of thought in this field (born out of cognitive psychology, and often known as the Santa Barbara school is entirely wedded to the computational theory of mind as an explanatory framework. Its unique aspect is to argue that the mind consists of a large number of functionally specialized (i.e., domain-specific computational mechanisms, or modules (the massive modularity hypothesis. Far from offering an alternative to, or an improvement on, the current perspective, we argue that evolutionary psychology is a mainstream computational theory, and that its arguments for domain-specificity often rest on shaky premises. We then go on to suggest that the various forms of e-cognition (i.e., embodied, embedded, enactive represent a true alternative to standard computational approaches, with an emphasis on cognitive integration or the extended mind hypothesis in particular. We feel this offers the most promise for human psychology because it incorporates the social and historical processes that are crucial to human ‘mind-making’ within an evolutionarily-informed framework. In addition to linking to other research areas in psychology, this approach is more likely to form productive links to other disciplines within the social sciences, not least by encouraging a healthy pluralism in approach.

  20. Evolutionary plant physiology: Charles Darwin's forgotten synthesis

    Science.gov (United States)

    Kutschera, Ulrich; Niklas, Karl J.

    2009-11-01

    Charles Darwin dedicated more than 20 years of his life to a variety of investigations on higher plants (angiosperms). It has been implicitly assumed that these studies in the fields of descriptive botany and experimental plant physiology were carried out to corroborate his principle of descent with modification. However, Darwin’s son Francis, who was a professional plant biologist, pointed out that the interests of his father were both of a physiological and an evolutionary nature. In this article, we describe Darwin’s work on the physiology of higher plants from a modern perspective, with reference to the following topics: circumnutations, tropisms and the endogenous oscillator model; the evolutionary patterns of auxin action; the root-brain hypothesis; phloem structure and photosynthesis research; endosymbioses and growth-promoting bacteria; photomorphogenesis and phenotypic plasticity; basal metabolic rate, the Pfeffer-Kleiber relationship and metabolic optimality theory with respect to adaptive evolution; and developmental constraints versus functional equivalence in relationship to directional natural selection. Based on a review of these various fields of inquiry, we deduce the existence of a Darwinian (evolutionary) approach to plant physiology and define this emerging scientific discipline as the experimental study and theoretical analysis of the functions of green, sessile organisms from a phylogenetic perspective.

  1. Paleoanthropology and evolutionary theory.

    Science.gov (United States)

    Tattersall, Ian

    2012-01-01

    Paleoanthropologists of the first half of the twentieth century were little concerned either with evolutionary theory or with the technicalities and broader implications of zoological nomenclature. In consequence, the paleoanthropological literature of the period consisted largely of a series of descriptions accompanied by authoritative pronouncements, together with a huge excess of hominid genera and species. Given the intellectual flimsiness of the resulting paleoanthropological framework, it is hardly surprising that in 1950 the ornithologist Ernst Mayr met little resistance when he urged the new postwar generation of paleoanthropologists to accept not only the elegant reductionism of the Evolutionary Synthesis but a vast oversimplification of hominid phylogenetic history and nomenclature. Indeed, the impact of Mayr's onslaught was so great that even when developments in evolutionary biology during the last quarter of the century brought other paleontologists to the realization that much more has been involved in evolutionary histories than the simple action of natural selection within gradually transforming lineages, paleoanthropologists proved highly reluctant to follow. Even today, paleoanthropologists are struggling to reconcile an intuitive realization that the burgeoning hominid fossil record harbors a substantial diversity of species (bringing hominid evolutionary patterns into line with that of other successful mammalian families), with the desire to cram a huge variety of morphologies into an unrealistically minimalist systematic framework. As long as this theoretical ambivalence persists, our perception of events in hominid phylogeny will continue to be distorted.

  2. Evolutionary Psychology is Not Evil! (… and Here’s Why …)

    OpenAIRE

    Glenn Geher

    2006-01-01

    Evolutionary psychology has faced ‘implacable hostility’ (Dawkins, 2005) from a number of intellectual fronts. Critics of evolutionary psychology have tried to paint this perspective variously as reductionist and overly deterministic, at best, and as sexist, racist, and downright evil at worst. The current paper argues that all psychological frameworks which assume that human beings are the result of the organic evolutionary forces of natural and sexual selection are, essentially, evolutionar...

  3. Retinoic acid signaling targets Hox genes during the amphioxus gastrula stage: insights into early anterior-posterior patterning of the chordate body plan.

    Science.gov (United States)

    Koop, Demian; Holland, Nicholas D; Sémon, Marie; Alvarez, Susana; de Lera, Angel Rodriguez; Laudet, Vincent; Holland, Linda Z; Schubert, Michael

    2010-02-01

    Previous studies of vertebrate development have shown that retinoic acid (RA) signaling at the gastrula stage strongly influences anterior-posterior (A-P) patterning of the neurula and later stages. However, much less is known about the more immediate effects of RA signaling on gene transcription and developmental patterning at the gastrula stage. To investigate the targets of RA signaling during the gastrula stage, we used the basal chordate amphioxus, in which gastrulation involves very minimal tissue movements. First, we determined the effect of altered RA signaling on expression of 42 genes (encoding transcription factors and components of major signaling cascades) known to be expressed in restricted domains along the A-P axis during the gastrula and early neurula stage. Of these 42 genes, the expression domains during gastrulation of only four (Hox1, Hox3, HNF3-1 and Wnt3) were spatially altered by exposure of the embryos to excess RA or to the RA antagonist BMS009. Moreover, blocking protein synthesis with puromycin before adding RA or BMS009 showed that only three of these genes (Hox1, Hox3 and HNF3-1) are direct RA targets at the gastrula stage. From these results we conclude that in the amphioxus gastrula RA signaling primarily acts via regulation of Hox transcription to establish positional identities along the A-P axis and that Hox1, Hox3, HNF3-1 and Wnt3 constitute a basal module of RA action during chordate gastrulation. PMID:19914237

  4. Archaeogenetics in evolutionary medicine.

    Science.gov (United States)

    Bouwman, Abigail; Rühli, Frank

    2016-09-01

    Archaeogenetics is the study of exploration of ancient DNA (aDNA) of more than 70 years old. It is an important part of the wider studies of many different areas of our past, including animal, plant and pathogen evolution and domestication events. Hereby, we address specifically the impact of research in archaeogenetics in the broader field of evolutionary medicine. Studies on ancient hominid genomes help to understand even modern health patterns. Human genetic microevolution, e.g. related to abilities of post-weaning milk consumption, and specifically genetic adaptation in disease susceptibility, e.g. towards malaria and other infectious diseases, are of the upmost importance in contributions of archeogenetics on the evolutionary understanding of human health and disease. With the increase in both the understanding of modern medical genetics and the ability to deep sequence ancient genetic information, the field of archaeogenetic evolutionary medicine is blossoming. PMID:27289479

  5. Emotional systems and the evolutionary tradition in psychology

    OpenAIRE

    Carlos Zerpa

    2013-01-01

    A brief review paper is presented about evolutionary tradition in emotional Psychology systems. Darwin approximation view to study of expression of emotion in humans is described. Some actual theoretical perspectives and researchers and future tendencies in emotional systems research since Darwinian tradition in Psychology and implications for disciplinary field are discussed.

  6. Evolutionary Computation:ao Overview

    Institute of Scientific and Technical Information of China (English)

    HeZhenya; WeiChengjian

    1997-01-01

    Evolutionary computation is a field of simulating evolution on a computer.Both aspects of it ,the problem solving aspect and the aspect of modeling natural evolution,are important.Simulating evolution on a computer results in stochastic optimization techniques that can outperform classical methods of optimization when applied to difficult real-world problems.There are currently four main avenues of research in simulated evolution:genetic algorithms,evolutionary programming,evolution strategies,and genetic programming.This paper presents a brief overview of thd field on evolutionary computation,including some theoretical issues,adaptive mechanisms,improvements,constrained optimizqtion,constrained satisfaction,evolutionary neural networks,evolutionary fuzzy systems,hardware evolution,evolutionary robotics,parallel evolutionary computation,and co-evolutionary models.The applications of evolutionary computation for optimizing system and intelligent information processing in telecommunications are also introduced.

  7. Studies in evolutionary agroecology

    DEFF Research Database (Denmark)

    Wille, Wibke

    of Evolutionary Agroecology that the highest yielding individuals do not necessarily perform best as a population. The investment of resources into strategies and structures increasing individual competitive ability carries a cost. If a whole population consists of individuals investing resources to compete......Darwinian evolution by natural selection is driven primarily by differential survival and reproduction among individuals in a population. When the evolutionary interest of an individual is in conflict with the interests of the population, the genes increasing individual fitness at the cost...

  8. Evolutionary Statistical Procedures

    CERN Document Server

    Baragona, Roberto; Poli, Irene

    2011-01-01

    This proposed text appears to be a good introduction to evolutionary computation for use in applied statistics research. The authors draw from a vast base of knowledge about the current literature in both the design of evolutionary algorithms and statistical techniques. Modern statistical research is on the threshold of solving increasingly complex problems in high dimensions, and the generalization of its methodology to parameters whose estimators do not follow mathematically simple distributions is underway. Many of these challenges involve optimizing functions for which analytic solutions a

  9. Part E: Evolutionary Computation

    DEFF Research Database (Denmark)

    2015-01-01

    Part E, Evolutionary Computation, edited by Professors Frank Neumann, Carsten Witt, Peter Merz, Carlos A. Coello Coello, Oliver Schütze, Thomas Bartz-Beielstein, Jörn Mehnen, and Günther Raidl, concerns the third fundamental element of what is traditionally being considered to be the core of Comp...

  10. Learning: An Evolutionary Analysis

    Science.gov (United States)

    Swann, Joanna

    2009-01-01

    This paper draws on the philosophy of Karl Popper to present a descriptive evolutionary epistemology that offers philosophical solutions to the following related problems: "What happens when learning takes place?" and "What happens in human learning?" It provides a detailed analysis of how learning takes place without any direct transfer of…

  11. Origins of evolutionary transitions

    Indian Academy of Sciences (India)

    Ellen Clarke

    2014-04-01

    An `evolutionary transition in individuality’ or `major transition’ is a transformation in the hierarchical level at which natural selection operates on a population. In this article I give an abstract (i.e. level-neutral and substrate-neutral) articulation of the transition process in order to precisely understand how such processes can happen, especially how they can get started.

  12. Recent Advances in Evolutionary Computation

    Institute of Scientific and Technical Information of China (English)

    Xin Yao; Yong Xu

    2006-01-01

    Evolutionary computation has experienced a tremendous growth in the last decade in both theoretical analyses and industrial applications. Its scope has evolved beyond its original meaning of "biological evolution" toward a wide variety of nature inspired computational algorithms and techniques, including evolutionary, neural, ecological, social and economical computation, etc., in a unified framework. Many research topics in evolutionary computation nowadays are not necessarily "evolutionary". This paper provides an overview of some recent advances in evolutionary computation that have been made in CERCIA at the University of Birmingham, UK. It covers a wide range of topics in optimization, learning and design using evolutionary approaches and techniques, and theoretical results in the computational time complexity of evolutionary algorithms. Some issues related to future development of evolutionary computation are also discussed.

  13. Evolutionary genomics of animal personality.

    Science.gov (United States)

    van Oers, Kees; Mueller, Jakob C

    2010-12-27

    Research on animal personality can be approached from both a phenotypic and a genetic perspective. While using a phenotypic approach one can measure present selection on personality traits and their combinations. However, this approach cannot reconstruct the historical trajectory that was taken by evolution. Therefore, it is essential for our understanding of the causes and consequences of personality diversity to link phenotypic variation in personality traits with polymorphisms in genomic regions that code for this trait variation. Identifying genes or genome regions that underlie personality traits will open exciting possibilities to study natural selection at the molecular level, gene-gene and gene-environment interactions, pleiotropic effects and how gene expression shapes personality phenotypes. In this paper, we will discuss how genome information revealed by already established approaches and some more recent techniques such as high-throughput sequencing of genomic regions in a large number of individuals can be used to infer micro-evolutionary processes, historical selection and finally the maintenance of personality trait variation. We will do this by reviewing recent advances in molecular genetics of animal personality, but will also use advanced human personality studies as case studies of how molecular information may be used in animal personality research in the near future. PMID:21078651

  14. Evolutionary Mechanism of Modern Circulation Industry Organization---From the Perspective of Evolutionary Economics%现代流通产业组织演化机理研究--基于演化经济学视角的分析

    Institute of Scientific and Technical Information of China (English)

    米辉

    2014-01-01

    从马克思分工理论引出的流通命题在我国新一轮的转型经济背景下具有新的理论内涵,而演化经济学相关理论符合现代流通业发展对动态的、系统的流通理论创新的诉求。通过演化经济学的分析手法,立足于流通过程在生产力、生产方式和消费方式之间的作用,深入探究了流通组织演化之“新奇”的产生,以及其作用下的流通产业组织演化传导机理。从分析中得出流通组织变迁实际上是一个自然选择过程,在常规演进动力下流通组织变迁的滞后性导致了流通产业的“路径依赖”和多业态均衡,这将为流通链两端的进一步变革造成积压性阻力。在此基础上为目前我国流通组织升级和政策制定提供理论建议。%Circulation proposition educed from Marx’s labor division theory has had a new theoretical connotation under the background of a new round of economic transition in China.The related theory of evolutionary economics meets the requirement that the development of modern circulation industry demands innovation in dynamic and systematic theory.Based on the analytical technique of evolutionary economics and the effects among productive force,mode of production and pattern of consumption in the process of circulation,the article deeply studies the generation of “novelty”from the evolution of circulation organization and evolutionary mechanism of circulation industry organization.It thinks that the evolution of circulation organization is in fact the process of natural selection,and the lagging behind in the evolution of circulation organization in conventional evolutionary dynamic results in “path dependence”and the balance of multiple commercial activities of circulation industry, which will hinder the revolution in circulation chain ends.Finally,it puts forward some theoretical suggestions on the upgrading of circulation organization and policy making in China.

  15. Evolutionary conservation of the mature oocyte proteome

    Directory of Open Access Journals (Sweden)

    Tamar Lotan

    2014-06-01

    Significance: The current study provides the first proteomic profile of an oocyte of a cnidarian organism the starlet sea anemone N. vectensis and gives new insights on the ancient origin of an oocyte proteome template. The comparative analysis with a chordate oocyte suggests that the oocyte proteome predates the divergence of the cnidarian and bilaterian lineages. In addition, the data generated in the study will serve as a valuable resource for further developmental and evolutional studies.

  16. Evolutionary constrained optimization

    CERN Document Server

    Deb, Kalyanmoy

    2015-01-01

    This book makes available a self-contained collection of modern research addressing the general constrained optimization problems using evolutionary algorithms. Broadly the topics covered include constraint handling for single and multi-objective optimizations; penalty function based methodology; multi-objective based methodology; new constraint handling mechanism; hybrid methodology; scaling issues in constrained optimization; design of scalable test problems; parameter adaptation in constrained optimization; handling of integer, discrete and mix variables in addition to continuous variables; application of constraint handling techniques to real-world problems; and constrained optimization in dynamic environment. There is also a separate chapter on hybrid optimization, which is gaining lots of popularity nowadays due to its capability of bridging the gap between evolutionary and classical optimization. The material in the book is useful to researchers, novice, and experts alike. The book will also be useful...

  17. Evolutionary status of Entamoeba

    Institute of Scientific and Technical Information of China (English)

    DONG Jiuhong; WEN Jianfan; XIN Dedong; LU Siqi

    2004-01-01

    In addition to its medical importance as parasitic pathogen, Entamoeba has aroused people's interest in its evolutionary status for a long time. Lacking mitochondrion and other intracellular organelles common to typical eukaryotes, Entamoeba and several other amitochondrial protozoans have been recognized as ancient pre-mitochondriate eukaryotes and named "archezoa", the most primitive extant eukaryotes. It was suggested that they might be living fossils that remained in a primitive stage of evolution before acquisition of organelles, lying close to the transition between prokaryotes and eukaryotes. However, recent studies revealed that Entamoeba contained an organelle, "crypton" or "mitosome", which was regarded as specialized or reductive mitochondrion. Relative molecular phylogenetic analyses also indicated the existence or the probable existence of mitochondrion in Entamoeba. Our phylogenetic analysis based on DNA topoisomerase II strongly suggested its divergence after some mitchondriate eukaryotes. Here, all these recent researches are reviewed and the evolutionary status of Entamoeba is discussed.

  18. Evolutionary biology of cancer.

    Science.gov (United States)

    Crespi, Bernard; Summers, Kyle

    2005-10-01

    Cancer is driven by the somatic evolution of cell lineages that have escaped controls on replication and by the population-level evolution of genes that influence cancer risk. We describe here how recent evolutionary ecological studies have elucidated the roles of predation by the immune system and competition among normal and cancerous cells in the somatic evolution of cancer. Recent analyses of the evolution of cancer at the population level show how rapid changes in human environments have augmented cancer risk, how strong selection has frequently led to increased cancer risk as a byproduct, and how anticancer selection has led to tumor-suppression systems, tissue designs that slow somatic evolution, constraints on morphological evolution and even senescence itself. We discuss how applications of the tools of ecology and evolutionary biology are poised to revolutionize our understanding and treatment of this disease.

  19. Introduction to Evolutionary Algorithms

    CERN Document Server

    Yu, Xinjie

    2010-01-01

    Evolutionary algorithms (EAs) are becoming increasingly attractive for researchers from various disciplines, such as operations research, computer science, industrial engineering, electrical engineering, social science, economics, etc. This book presents an insightful, comprehensive, and up-to-date treatment of EAs, such as genetic algorithms, differential evolution, evolution strategy, constraint optimization, multimodal optimization, multiobjective optimization, combinatorial optimization, evolvable hardware, estimation of distribution algorithms, ant colony optimization, particle swarm opti

  20. Evolutionary health psychology

    OpenAIRE

    Dickins, Thomas E.

    2006-01-01

    For the last decade and a half the discipline of Evolutionary Psychology (EP) has been developing with great success. The first collection of significant papers was published in 1992 (Barkow et al.) and recently a landmark handbook has been produced summing the progress so far, as well as setting an agenda for future study (Buss, 2005). Unlike other areas within Psychology, EP extends its interest to all behaviours, rightly seeing them as part of an evolved phenotype, and health has not escap...

  1. Evolutionary economics and psychology

    OpenAIRE

    Witt, Ulrich

    2006-01-01

    Evolutionary economics is a paradigm for explaining the transformation of the economy. To achieve its goal, it needs being founded on a proper theory of economic behavior. The paper discusses these foundations. It is argued that the historical malleability of economic behavior is based on the interactions between innate behavior dispositions and adaptation mechanisms on the one hand and the limited, and always selective, cognitive and observational learning that contributes to an ever more ex...

  2. Evolutionary game design

    CERN Document Server

    Browne, Cameron

    2011-01-01

    The book describes the world's first successful experiment in fully automated board game design. Evolutionary methods were used to derive new rule sets within a custom game description language, and self-play trials used to estimate each derived game's potential to interest human players. The end result is a number of new and interesting games, one of which has proved popular and gone on to be commercially published.

  3. Evolutionary theory of cancer.

    Science.gov (United States)

    Attolini, Camille Stephan-Otto; Michor, Franziska

    2009-06-01

    As Theodosius Dobzhansky famously noted in 1973, "Nothing in biology makes sense except in the light of evolution," and cancer is no exception to this rule. Our understanding of cancer initiation, progression, treatment, and resistance has advanced considerably by regarding cancer as the product of evolutionary processes. Here we review the literature of mathematical models of cancer evolution and provide a synthesis and discussion of the field.

  4. Conserved developmental expression of Fezf in chordates and Drosophila and the origin of the Zona Limitans Intrathalamica (ZLI) brain organizer

    OpenAIRE

    Irimia Manuel; Piñeiro Cristina; Maeso Ignacio; Gómez-Skarmeta José; Casares Fernando; Garcia-Fernàndez Jordi

    2010-01-01

    Abstract Background The zona limitans intrathalamica (ZLI) and the isthmus organizer (IsO) are two major secondary organizers of vertebrate brain development. These organizers are located at the interface of the expression domains of key patterning genes (Fezf-Irx and Otx-Gbx, respectively). To gain insights into the evolutionary origin of the ZLI, we studied Fezf in bilaterians. Results In this paper, we identified a conserved sequence motif (Fezf box) in all bilaterians. We report the expre...

  5. Cryptic Genetic Variation in Evolutionary Developmental Genetics

    Directory of Open Access Journals (Sweden)

    Annalise B. Paaby

    2016-06-01

    Full Text Available Evolutionary developmental genetics has traditionally been conducted by two groups: Molecular evolutionists who emphasize divergence between species or higher taxa, and quantitative geneticists who study variation within species. Neither approach really comes to grips with the complexities of evolutionary transitions, particularly in light of the realization from genome-wide association studies that most complex traits fit an infinitesimal architecture, being influenced by thousands of loci. This paper discusses robustness, plasticity and lability, phenomena that we argue potentiate major evolutionary changes and provide a bridge between the conceptual treatments of macro- and micro-evolution. We offer cryptic genetic variation and conditional neutrality as mechanisms by which standing genetic variation can lead to developmental system drift and, sheltered within canalized processes, may facilitate developmental transitions and the evolution of novelty. Synthesis of the two dominant perspectives will require recognition that adaptation, divergence, drift and stability all depend on similar underlying quantitative genetic processes—processes that cannot be fully observed in continuously varying visible traits.

  6. Evolutionary consequences of autopolyploidy.

    Science.gov (United States)

    Parisod, Christian; Holderegger, Rolf; Brochmann, Christian

    2010-04-01

    Autopolyploidy is more common in plants than traditionally assumed, but has received little attention compared with allopolyploidy. Hence, the advantages and disadvantages of genome doubling per se compared with genome doubling coupled with hybridizations in allopolyploids remain unclear. Autopolyploids are characterized by genomic redundancy and polysomic inheritance, increasing effective population size. To shed light on the evolutionary consequences of autopolyploidy, we review a broad range of studies focusing on both synthetic and natural autopolyploids encompassing levels of biological organization from genes to evolutionary lineages. The limited evidence currently available suggests that autopolyploids neither experience strong genome restructuring nor wide reorganization of gene expression during the first generations following genome doubling, but that these processes may become more important in the longer term. Biogeographic and ecological surveys point to an association between the formation of autopolyploid lineages and environmental change. We thus hypothesize that polysomic inheritance may provide a short-term evolutionary advantage for autopolyploids compared to diploid relatives when environmental change enforces range shifts. In addition, autopolyploids should possess increased genome flexibility, allowing them to adapt and persist across heterogeneous landscapes in the long run. PMID:20070540

  7. THE THEORY OF THE FIRM AND THE EVOLUTIONARY GAMES

    Directory of Open Access Journals (Sweden)

    Sirghi Nicoleta

    2013-07-01

    Full Text Available The neoclassical theory of the firm deals with the pattern of perfect competition, within which the perfect information available to economic agents provides instant allocation of production factors and access to economic goods. The Austrian School (C. Menger, L. von Mises, Hayek, etc. supported the idea of minimal state intervention on the markets, bringing important conceptual developments on the theory of the firm. Hirschleifer (1982 put forward the model of social and institutional functioning, arguing that the game theory is able to predict the outcome of the collective behavior and the human characteristics necessary for building the respective institutions.The evolutionary theory provides the firm and the entrepreneur the recognition of the functions of innovation, of generating and exploiting information and of organizing and coordinating production. The evolutionary perspective of the firm assumes the existence of a body of knowledge that is acquired through and builds up the organizational memory, subsequently found in routines, all choices being made based on these routines (Nelson and Winter, 2002. The evolution of the firm is considered to be similar to natural selection, but unlike the classic market selection, the evolutionists suggest the existence of a plurality of selection media. The present research is structured as follows: a brief introduction into the theories of the firm, the second part of the paper analyzes the theories of the firm from an institutional, neo-institutional and evolutionary perspective. In the third part of the paper the evolutionary games are described and analyzed from the evolutionary perspective of the firm. The last part of the paper represents a study of the “hawk-dove” game dynamic replicator. The final conclusions of the paper show that the evolutionary theory brings valuable contributions to the foundation of explanations regarding economic phenomena, indicating new directions for advanced

  8. Distinctive expression patterns of Hedgehog pathway genes in the Ciona intestinalis larva: implications for a role of Hedgehog signaling in postembryonic development and chordate evolution.

    Science.gov (United States)

    Islam, A F M Tariqul; Moly, Pricila Khan; Miyamoto, Yuki; Kusakabe, Takehiro G

    2010-02-01

    Members of the Hedgehog (Hh) family are soluble ligands that orchestrate a wide spectrum of developmental processes ranging from left-right axis determination of the embryo to tissue patterning and organogenesis. Tunicates, including ascidians, are the closest relatives of vertebrates, and elucidation of Hh signaling in ascidians should provide an important clue towards better understanding the role of this pathway in development. In previous studies, expression patterns of genes encoding Hh and its downstream factor Gli have been examined up to the tailbud stage in the ascidian embryo, but their expression in the larva has not been reported. Here we show the spatial expression patterns of hedgehog (Ci-hh1, Ci-hh2), patched (Ci-ptc), smoothened (Ci-smo), and Gli (Ci-Gli) orthologs in larvae of the ascidian Ciona intestinalis. The expression patterns of Ci-hh2 and Ci-Gli dramatically change during the period between the late tailbud embryo and the swimming larva. At the larval stage, expression of Ci-Gli was found in a central part of the endoderm and in the visceral ganglion, while Ci-hh2 was expressed in two discrete endodermal regions, anteriorly and posteriorly adjacent to the cells expressing Gli. The expression patterns of these genes suggest that the Hh ligand controls postembryonic development of the endoderm and the central nervous system. Expression of a gene encoding Hh in the anterior and/or pharyngeal endoderm is probably an ancient chordate character; diversification of regulation and targets of the Hh signaling in this region may have played a major role in the evolution of chordate body structures.

  9. Evolutionary modelling of transitions to sustainable development

    International Nuclear Information System (INIS)

    This thesis has examined how evolutionary economics can contribute to modelling the micromechanisms that underlie transitions towards sustainable development. In general, transitions are fundamental or structural system changes. They involve, or even require, escaping lock-in of dominant, environmentally unsustainable technologies, introducing major technical or social innovations, and changing prevailing social practices and structures. Due to the complexity of socioeconomic interactions, it is not always possible to identify, and thus target with appropriate policy instruments, causes of specific unsustainable patterns of behaviour. Formal modelling exercises can help improve our understanding of the interaction of various transition mechanisms which are otherwise difficult to grasp intuitively. They allow exploring effects of policy interventions in complex systems. However, existing models of transitions focus on social phenomena and seldom address economic problems. As opposed, mainstream (neoclassical) economic models of technological change do not account for social interactions, and changing heterogeneity of users and their perspectives - even though all of these can influence the direction of innovations and patterns of socio-technological development. Evolutionary economics offers an approach that goes beyond neoclassical economics - in the sense of employing more realistic assumptions regarding the behaviour and heterogeneity of consumers, firms and investors. It can complement current transition models by providing them with a better understanding of associated economic dynamics. In this thesis, formal models were proposed to illustrate the usefulness of a range of evolutionary-economic techniques for modelling transitions. Modelling exercises aimed to explain the core properties of socio-economic systems, such as lock-in, path-dependence, coevolution, group selection and recombinant innovation. The studies collected in this dissertation illustrate that

  10. EVOLUTIONARY THEORY AND THE MARKET COMPETITION

    Directory of Open Access Journals (Sweden)

    SIRGHI Nicoleta

    2014-12-01

    Full Text Available Evolutionary theory study of processes that transform economy for firms, institutions, industries, employment, production, trade and growth within, through the actions of diverse agents from experience and interactions, using evolutionary methodology. Evolutionary theory analyses the unleashing of a process of technological and institutional innovation by generating and testing a diversity of ideas which discover and accumulate more survival value for the costs incurred than competing alternatives.This paper presents study the behavior of the firms on the market used the evolutionary theory.The paper is to present in full the developments that have led to the re-assessment of theories of firms starting from the criticism on Coase's theory based on the lack of testable hypotheses and on non-operative definition of transaction costs. In the literature in the field studies on firms were allotted a secondary place for a long period of time, to date the new theories of the firm hold a dominant place in the firms’ economic analysis. In an article, published in 1937, Ronald H. Coase identified the main sources of the cost of using the market mechanism. The firms theory represent a issue intensively studied in the literature in the field, regarding the survival, competitiveness and innovation of firm on the market. The research of Nelson and Winter, “An Evolutionary Theory of Economic Change” (1982 is the starting point for a modern literature in the field which considers the approach of the theory of the firm from an evolutionary perspective. Nelson and Winter have shown that the “orthodox” theory, is objectionable primarily by the fact that the hypothesis regarding profit maximization has a normative character and is not valid in any situation. Nelson and Winter reconsidered their microeconomic analysis showing that excessive attention should not be paid to market equilibrium but rather to dynamic processes resulting from irreversible

  11. When not to have another baby: An evolutionary approach to low fertility

    Directory of Open Access Journals (Sweden)

    Ruth Mace

    2014-04-01

    Full Text Available Background: In this paper, I explain the theoretical foundations of fertility from the perspective of evolutionary demography and evolutionary anthropology. Objective: My goal in this paper is to provide examples of how evolutionary demography is generating and testing new hypotheses about human fertility and parental behaviour. Methods: To illustrate the paradigm of low fertility, I present several evolutionary explanations for reduced fertility, or no fertility at all. The explanations I cite are drawn from studies on child maltreatment, homosexual preference, post-demographic transition low fertility, and late-life low fertility (menopause, as these are phenomena that appear to challenge evolutionary approaches. Conclusions: I find that the sophisticated tools of behavioural ecology and evolutionary anthropology and demography can do more than simply explain high fertility, and are currently being used to generate and test new hypotheses about fertility, including hypotheses that address the issue of low fertility.

  12. 演化博弈视角下移动支付的商业模式研究%Study on Business Model of Mobile Payments under the Perspective of Evolutionary Game

    Institute of Scientific and Technical Information of China (English)

    樊自甫; 魏晶莹; 万晓榆

    2012-01-01

    The rapid development of mobile payment industry is inseparable from effective business model, the formation and choice of which become one of the key issues. Assuming that the mobile operators and financial institutions in the mobile payment industrial chain are limitedly rational, this paper makes use of the evolutionary game theory to establish asymmetric replicator dynamics on cooperation and competition of the predominance for the mobile operators and financial institutions. By analyzing this model, the evolutionary trend of mobile payment and the parametric conditions which need to be met for selecting different business models are obtained. The results provide suggestions for policy decision of mobile operators and financial institutions in the mobile payment industrial chain.%假设移动支付产业链上的主体移动运营商和金融机构为有限理性,运用演化博弈理论,建立移动运营商和金融机构关于主导权合作竞争的非对称复制动态模型。通过对该模型的分析与研究,得出移动支付商业模式的演化趋势,以及选择不同的商业模式需满足的参数条件,为移动运营商和金融机构在移动支付产业链上做出最佳的策略决策提供了指导性的建议。

  13. Constraints as evolutionary systems

    CERN Document Server

    Rácz, István

    2016-01-01

    The constraint equations for smooth $[n+1]$-dimensional (with $n\\geq 3$) Riemannian or Lorentzian spaces satisfying the Einstein field equations are considered. It is shown, regardless of the signature of the primary space, that the constraints can be put into the form of an evolutionary system comprised either by a first order symmetric hyperbolic system and a parabolic equation or, alternatively, by a strongly hyperbolic system and a subsidiary algebraic relation. In both cases the (local) existence and uniqueness of solutions are also discussed.

  14. SEARCH and a computational perspective of evolution

    Energy Technology Data Exchange (ETDEWEB)

    Kargupta, H.

    1996-05-01

    This paper develops an alternate perspective of natural evolution using the SEARCH (Search Envisioned As Relation and Class Hierarchizing) framework (Kargupta, 1995). Some problems of existing views about evolutionary computation are noted. An attempt is made to fulfill these deficiencies using a new computational perspective of gene expression based on a decomposition of blackbox optimization in terms of relations, classes, samples, and partial ordering.

  15. Evolutionary Psychology is Not Evil! (… and Here’s Why …

    Directory of Open Access Journals (Sweden)

    Glenn Geher

    2006-12-01

    Full Text Available Evolutionary psychology has faced ‘implacable hostility’ (Dawkins, 2005from a number of intellectual fronts. Critics of evolutionary psychology have triedto paint this perspective variously as reductionist and overly deterministic, at best,and as sexist, racist, and downright evil at worst. The current paper argues that allpsychological frameworks which assume that human beings are the result of theorganic evolutionary forces of natural and sexual selection are, essentially,evolutionary in nature (regardless of whether they traditionally fall under the labelof evolutionary psychology. In other words, the perspective presented here arguesthat all psychology is evolutionary psychology. Two specific mis-characterizationsof evolutionary psychology ((a that it is eugenicist in nature and (b that it is afully non-situationist, immutable perspective on behavior are addressed here withan eye toward elaborating on how these distorted conceptions of evolutionarypsychology are non-constructive and non-progressive. A final section focuses onhow the social sciences in general could benefit from being evolutionized.

  16. Evolutionary status of Polaris

    CERN Document Server

    Fadeyev, Yu A

    2015-01-01

    Hydrodynamic models of short--period Cepheids were computed to determine the pulsation period as a function of evolutionary time during the first and third crossings of the instability strip. The equations of radiation hydrodynamics and turbulent convection for radial stellar pulsations were solved with the initial conditions obtained from the evolutionary models of population I stars (X=0.7, Z=0.02) with masses from 5.2 to 6.5 Msol and the convective core overshooting parameter 0.1 <= aov <= 0.3. In Cepheids with period of 4 d the rate of pulsation period change during the first crossing of the instability strip is over fifty times larger than that during the third crossing. Polaris is shown to cross the instability strip for the first time and to be the fundamental mode pulsator. The best agreement between the predicted and observed rates of period change was obtained for the model with mass of 5.4 Msol and the overshooting parameter aov=0.25. The bolometric luminosity and radius are L = 1.26e3 Lsol a...

  17. Evolutionary status of Polaris

    Science.gov (United States)

    Fadeyev, Yu. A.

    2015-05-01

    Hydrodynamic models of short-period Cepheids were computed to determine the pulsation period as a function of evolutionary time during the first and third crossings of the instability strip. The equations of radiation hydrodynamics and turbulent convection for radial stellar pulsations were solved with the initial conditions obtained from the evolutionary models of Population I stars (X = 0.7, Z = 0.02) with masses from 5.2 to 6.5 M⊙ and the convective core overshooting parameter 0.1 ≤ αov ≤ 0.3. In Cepheids with period of 4 d the rate of pulsation period change during the first crossing of the instability strip is over 50 times larger than that during the third crossing. Polaris is shown to cross the instability strip for the first time and to be the fundamental mode pulsator. The best agreement between the predicted and observed rates of period change was obtained for the model with mass of 5.4 M⊙ and the overshooting parameter αov = 0.25. The bolometric luminosity and radius are L = 1.26 × 103 L⊙ and R = 37.5 R⊙, respectively. In the HR diagram, Polaris is located at the red edge of the instability strip.

  18. Evolutionary Psychology: The Academic Debate

    OpenAIRE

    Suplizio, Jean

    2005-01-01

    This dissertation examines the academic debate that surrounds the new field called "Evolutionary Psychology." Evolutionary psychology has emerged as the most popular successor theory to human sociobiology. Its proponents search for evolved psychological mechanisms and emphasize universal features of the human mind. My thesis is that in order to flourish evolutionary psychologists must engage other researchers on equal terms -- something they have not been doing. To show this, I examine the...

  19. Differential regulation of ParaHox genes by retinoic acid in the invertebrate chordate amphioxus (Branchiostoma floridae).

    Science.gov (United States)

    Osborne, Peter W; Benoit, Gérard; Laudet, Vincent; Schubert, Michael; Ferrier, David E K

    2009-03-01

    The ParaHox cluster is the evolutionary sister to the Hox cluster. Like the Hox cluster, the ParaHox cluster displays spatial and temporal regulation of the component genes along the anterior/posterior axis in a manner that correlates with the gene positions within the cluster (a feature called collinearity). The ParaHox cluster is however a simpler system to study because it is composed of only three genes. We provide a detailed analysis of the amphioxus ParaHox cluster and, for the first time in a single species, examine the regulation of the cluster in response to a single developmental signalling molecule, retinoic acid (RA). Embryos treated with either RA or RA antagonist display altered ParaHox gene expression: AmphiGsx expression shifts in the neural tube, and the endodermal boundary between AmphiXlox and AmphiCdx shifts its anterior/posterior position. We identified several putative retinoic acid response elements and in vitro assays suggest some may participate in RA regulation of the ParaHox genes. By comparison to vertebrate ParaHox gene regulation we explore the evolutionary implications. This work highlights how insights into the regulation and evolution of more complex vertebrate arrangements can be obtained through studies of a simpler, unduplicated amphioxus gene cluster. PMID:19103191

  20. Wildlife conservation and animal temperament: causes and consequences of evolutionary change for captive, reintroduced, and wild populations

    NARCIS (Netherlands)

    McDougall, P.T.; Réale, D.; Sol, D.; Reader, S.M.

    2006-01-01

    We argue that animal temperament is an important concept for wildlife conservation science and review causes and consequences of evolutionary changes in temperament traits that may occur in captive-breeding programmes. An evolutionary perspective is valid because temperament traits are heritable, li

  1. Women in evolution - highlighting the changing face of evolutionary biology.

    Science.gov (United States)

    Wellenreuther, Maren; Otto, Sarah

    2016-01-01

    The face of science has changed. Women now feature alongside men at the forefront of many fields, and this is particularly true in evolutionary biology. This special issue celebrates the outstanding achievements and contributions of women in evolutionary biology, by highlighting a sample of their research and accomplishments. In addition to original research contributions, this collection of articles contains personal reflections to provide perspective and advice on succeeding as a woman in science. By showcasing the diversity and research excellence of women and drawing on their experiences, we wish to enhance the visibility of female scientists and provide inspiration as well as role models. These are exciting times for evolutionary biology, and the field is richer and stronger for the diversity of voices contributing to the field. PMID:27087836

  2. Women in evolution - highlighting the changing face of evolutionary biology.

    Science.gov (United States)

    Wellenreuther, Maren; Otto, Sarah

    2016-01-01

    The face of science has changed. Women now feature alongside men at the forefront of many fields, and this is particularly true in evolutionary biology. This special issue celebrates the outstanding achievements and contributions of women in evolutionary biology, by highlighting a sample of their research and accomplishments. In addition to original research contributions, this collection of articles contains personal reflections to provide perspective and advice on succeeding as a woman in science. By showcasing the diversity and research excellence of women and drawing on their experiences, we wish to enhance the visibility of female scientists and provide inspiration as well as role models. These are exciting times for evolutionary biology, and the field is richer and stronger for the diversity of voices contributing to the field.

  3. Evolutionary developmental pathology and anthropology: A new field linking development, comparative anatomy, human evolution, morphological variations and defects, and medicine.

    Science.gov (United States)

    Diogo, Rui; Smith, Christopher M; Ziermann, Janine M

    2015-11-01

    We introduce a new subfield of the recently created field of Evolutionary-Developmental-Anthropology (Evo-Devo-Anth): Evolutionary-Developmental-Pathology-and-Anthropology (Evo-Devo-P'Anth). This subfield combines experimental and developmental studies of nonhuman model organisms, biological anthropology, chordate comparative anatomy and evolution, and the study of normal and pathological human development. Instead of focusing on other organisms to try to better understand human development, evolution, anatomy, and pathology, it places humans as the central case study, i.e., as truly model organism themselves. We summarize the results of our recent Evo-Devo-P'Anth studies and discuss long-standing questions in each of the broader biological fields combined in this subfield, paying special attention to the links between: (1) Human anomalies and variations, nonpentadactyly, homeotic transformations, and "nearest neighbor" vs. "find and seek" muscle-skeleton associations in limb+facial muscles vs. other head muscles; (2) Developmental constraints, the notion of "phylotypic stage," internalism vs. externalism, and the "logic of monsters" vs. "lack of homeostasis" views about human birth defects; (3) Human evolution, reversions, atavisms, paedomorphosis, and peromorphosis; (4) Scala naturae, Haeckelian recapitulation, von Baer's laws, and parallelism between phylogeny and development, here formally defined as "Phylo-Devo parallelism"; and (5) Patau, Edwards, and Down syndrome (trisomies 13, 18, 21), atavisms, apoptosis, heart malformations, and medical implications.

  4. Evolutionary developmental pathology and anthropology: A new field linking development, comparative anatomy, human evolution, morphological variations and defects, and medicine.

    Science.gov (United States)

    Diogo, Rui; Smith, Christopher M; Ziermann, Janine M

    2015-11-01

    We introduce a new subfield of the recently created field of Evolutionary-Developmental-Anthropology (Evo-Devo-Anth): Evolutionary-Developmental-Pathology-and-Anthropology (Evo-Devo-P'Anth). This subfield combines experimental and developmental studies of nonhuman model organisms, biological anthropology, chordate comparative anatomy and evolution, and the study of normal and pathological human development. Instead of focusing on other organisms to try to better understand human development, evolution, anatomy, and pathology, it places humans as the central case study, i.e., as truly model organism themselves. We summarize the results of our recent Evo-Devo-P'Anth studies and discuss long-standing questions in each of the broader biological fields combined in this subfield, paying special attention to the links between: (1) Human anomalies and variations, nonpentadactyly, homeotic transformations, and "nearest neighbor" vs. "find and seek" muscle-skeleton associations in limb+facial muscles vs. other head muscles; (2) Developmental constraints, the notion of "phylotypic stage," internalism vs. externalism, and the "logic of monsters" vs. "lack of homeostasis" views about human birth defects; (3) Human evolution, reversions, atavisms, paedomorphosis, and peromorphosis; (4) Scala naturae, Haeckelian recapitulation, von Baer's laws, and parallelism between phylogeny and development, here formally defined as "Phylo-Devo parallelism"; and (5) Patau, Edwards, and Down syndrome (trisomies 13, 18, 21), atavisms, apoptosis, heart malformations, and medical implications. PMID:26293597

  5. The evolutionary origins and significance of drug addiction

    OpenAIRE

    Saah Tammy

    2005-01-01

    Abstract By looking at drug addiction from an evolutionary perspective, we may understand its underlying significance and evaluate its three-fold nature: biology, psychology, and social influences. In this investigation it is important to delve into the co-evolution of mammalian brains and ancient psychotropic plants. Gaining an understanding of the implications of ancient psychotropic substance use in altering mammalian brains will assist in assessing the causes and effects of addiction in a...

  6. Structural, Functional and Evolutionary Studies on Prolyl-Hydroxylases

    OpenAIRE

    Scotti, John Salvatore; Christopher J. Schofield

    2014-01-01

    This thesis studies the prolyl-hydroxylase family of 2-oxoglutarate dependent oxygenases from structural, functional and evolutionary perspectives. The role of prolyl-hydroxylation was first identified in collagen, wherein hydroxyproline was found to stabilise the collagen triple helix. In the 1960s, the presence of hydroxyproline in collagen was found to be a result of enzyme catalysed protein modification. An enzyme, now known as collagen prolyl-4-hydroxylase (CP4H), was found to be com...

  7. Studying Collective Human Decision Making and Creativity with Evolutionary Computation.

    Science.gov (United States)

    Sayama, Hiroki; Dionne, Shelley D

    2015-01-01

    We report a summary of our interdisciplinary research project "Evolutionary Perspective on Collective Decision Making" that was conducted through close collaboration between computational, organizational, and social scientists at Binghamton University. We redefined collective human decision making and creativity as evolution of ecologies of ideas, where populations of ideas evolve via continual applications of evolutionary operators such as reproduction, recombination, mutation, selection, and migration of ideas, each conducted by participating humans. Based on this evolutionary perspective, we generated hypotheses about collective human decision making, using agent-based computer simulations. The hypotheses were then tested through several experiments with real human subjects. Throughout this project, we utilized evolutionary computation (EC) in non-traditional ways-(1) as a theoretical framework for reinterpreting the dynamics of idea generation and selection, (2) as a computational simulation model of collective human decision-making processes, and (3) as a research tool for collecting high-resolution experimental data on actual collaborative design and decision making from human subjects. We believe our work demonstrates untapped potential of EC for interdisciplinary research involving human and social dynamics.

  8. Evolutionary patterns of RNA-based gene duplicates in Caenorhabditis nematodes coincide with their genomic features

    Directory of Open Access Journals (Sweden)

    Zou Ming

    2012-08-01

    Full Text Available Abstract Background RNA-based gene duplicates (retrocopies played pivotal roles in many physiological processes. Nowadays, functional retrocopies have been systematically identified in several mammals, fruit flies, plants, zebrafish and other chordates, etc. However, studies about this kind of duplication in Caenorhabditis nematodes have not been reported. Findings We identified 43, 48, 43, 9, and 42 retrocopies, of which 6, 15, 18, 3, and 13 formed chimeric genes in C. brenneri, C. briggsae, C. elegans, C. japonica, and C. remanei, respectively. At least 5 chimeric types exist in Caenorhabditis species, of which retrocopy recruiting both N and C terminus is the commonest one. Evidences from different analyses demonstrate many retrocopies and almost all chimeric genes may be functional in these species. About half of retrocopies in each species has coordinates in other species, and we suggest that retrocopies in closely related species may be helpful in identifying retrocopies for one certain species. Conclusions A number of retrocopies and chimeric genes exist in Caenorhabditis genomes, and some of them may be functional. The evolutionary patterns of these genes may correlate with their genomic features, such as the activity of retroelements, the high rate of mutation and deletion rate, and a large proportion of genes subject to trans-splicing.

  9. Spore: Spawning Evolutionary Misconceptions?

    Science.gov (United States)

    Bean, Thomas E.; Sinatra, Gale M.; Schrader, P. G.

    2010-10-01

    The use of computer simulations as educational tools may afford the means to develop understanding of evolution as a natural, emergent, and decentralized process. However, special consideration of developmental constraints on learning may be necessary when using these technologies. Specifically, the essentialist (biological forms possess an immutable essence), teleological (assignment of purpose to living things and/or parts of living things that may not be purposeful), and intentionality (assumption that events are caused by an intelligent agent) biases may be reinforced through the use of computer simulations, rather than addressed with instruction. We examine the video game Spore for its depiction of evolutionary content and its potential to reinforce these cognitive biases. In particular, we discuss three pedagogical strategies to mitigate weaknesses of Spore and other computer simulations: directly targeting misconceptions through refutational approaches, targeting specific principles of scientific inquiry, and directly addressing issues related to models as cognitive tools.

  10. Molecular evolutionary analysis of ABCB5: the ancestral gene is a full transporter with potentially deleterious single nucleotide polymorphisms.

    Directory of Open Access Journals (Sweden)

    Karobi Moitra

    Full Text Available BACKGROUND: ABCB5 is a member of the ABC protein superfamily, which includes the transporters ABCB1, ABCC1 and ABCG2 responsible for causing drug resistance in cancer patients and also several other transporters that have been linked to human disease. The ABCB5 full transporter (ABCB5.ts is expressed in human testis and its functional significance is presently unknown. Another variant of this transporter, ABCB5 beta possess a "half-transporter-like" structure and is expressed in melanoma stem cells, normal melanocytes, and other types of pigment cells. ABCB5 beta has important clinical implications, as it may be involved with multidrug resistance in melanoma stem cells, allowing these stem cells to survive chemotherapeutic regimes. METHODOLOGY/PRINCIPAL FINDINGS: We constructed and examined in detail topological structures of the human ABCB5 protein and determined in-silico the cSNPs (coding single nucleotide polymorphisms that may affect its function. Evolutionary analysis of ABCB5 indicated that ABCB5, ABCB1, ABCB4, and ABCB11 share a common ancestor, which began duplicating early in the evolutionary history of chordates. This suggests that ABCB5 has evolved as a full transporter throughout its evolutionary history. CONCLUSIONS/SIGNIFICANCE: From our in-silco analysis of cSNPs we found that a large number of non-synonymous cSNPs map to important functional regions of the protein suggesting that these SNPs if present in human populations may play a role in diseases associated with ABCB5. From phylogenetic analyses, we have shown that ABCB5 evolved as a full transporter throughout its evolutionary history with an absence of any major shifts in selection between the various lineages suggesting that the function of ABCB5 has been maintained during mammalian evolution. This finding would suggest that ABCB5 beta may have evolved to play a specific role in human pigment cells and/or melanoma cells where it is predominantly expressed.

  11. Two Aspects of Evolutionary Algorithms

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper we discuss the paradigm of evolutionary algorithms (Eas). We argue about the need for new heuristics in real-world problem solving, discussing reasons why some problems are difficult tosolve. After introducing the main concepts of evolutionary algorithms, we concentrate on two issues:(1)self-adaptation of the parameters of EA, and (2) handling constraints.

  12. Topics of Evolutionary Computation 2001

    DEFF Research Database (Denmark)

    Ursem, Rasmus Kjær

    This booklet contains the student reports from the course: Topics of Evolutionary Computation, Fall 2001, given by Thiemo Krink, Rene Thomsen and Rasmus K. Ursem......This booklet contains the student reports from the course: Topics of Evolutionary Computation, Fall 2001, given by Thiemo Krink, Rene Thomsen and Rasmus K. Ursem...

  13. Open Issues in Evolutionary Robotics.

    Science.gov (United States)

    Silva, Fernando; Duarte, Miguel; Correia, Luís; Oliveira, Sancho Moura; Christensen, Anders Lyhne

    2016-01-01

    One of the long-term goals in evolutionary robotics is to be able to automatically synthesize controllers for real autonomous robots based only on a task specification. While a number of studies have shown the applicability of evolutionary robotics techniques for the synthesis of behavioral control, researchers have consistently been faced with a number of issues preventing the widespread adoption of evolutionary robotics for engineering purposes. In this article, we review and discuss the open issues in evolutionary robotics. First, we analyze the benefits and challenges of simulation-based evolution and subsequent deployment of controllers versus evolution on real robotic hardware. Second, we discuss specific evolutionary computation issues that have plagued evolutionary robotics: (1) the bootstrap problem, (2) deception, and (3) the role of genomic encoding and genotype-phenotype mapping in the evolution of controllers for complex tasks. Finally, we address the absence of standard research practices in the field. We also discuss promising avenues of research. Our underlying motivation is the reduction of the current gap between evolutionary robotics and mainstream robotics, and the establishment of evolutionary robotics as a canonical approach for the engineering of autonomous robots. PMID:26581015

  14. Open Issues in Evolutionary Robotics.

    Science.gov (United States)

    Silva, Fernando; Duarte, Miguel; Correia, Luís; Oliveira, Sancho Moura; Christensen, Anders Lyhne

    2016-01-01

    One of the long-term goals in evolutionary robotics is to be able to automatically synthesize controllers for real autonomous robots based only on a task specification. While a number of studies have shown the applicability of evolutionary robotics techniques for the synthesis of behavioral control, researchers have consistently been faced with a number of issues preventing the widespread adoption of evolutionary robotics for engineering purposes. In this article, we review and discuss the open issues in evolutionary robotics. First, we analyze the benefits and challenges of simulation-based evolution and subsequent deployment of controllers versus evolution on real robotic hardware. Second, we discuss specific evolutionary computation issues that have plagued evolutionary robotics: (1) the bootstrap problem, (2) deception, and (3) the role of genomic encoding and genotype-phenotype mapping in the evolution of controllers for complex tasks. Finally, we address the absence of standard research practices in the field. We also discuss promising avenues of research. Our underlying motivation is the reduction of the current gap between evolutionary robotics and mainstream robotics, and the establishment of evolutionary robotics as a canonical approach for the engineering of autonomous robots.

  15. Evolutionary Design of Boolean Functions

    Institute of Scientific and Technical Information of China (English)

    WANG Zhang-yi; ZHANG Huan-guo; QIN Zhong-ping; MENG Qing-shu

    2005-01-01

    We use evolutionary computing to synthesize Boolean functions randomly. By using specific crossover and mutation operator in evolving process and modifying search space and fitness function, we get some high non-linearity functions which have other good cryptography characteristics such as autocorrelation etc. Comparing to other heuristic search techniques, evolutionary computing approach is more effective because of global search strategy and implicit parallelism.

  16. Evolutionary Explanation and the Record of Interest: Using Evolutionary Archaeology and Dual-Inheritance Theory to Explain the Archaeological Record

    OpenAIRE

    Cochrane, E.

    2009-01-01

    Book description: This volume offers an integrative approach to the application of evolutionary theory in studies of cultural transmission and social evolution and reveals the enormous range of ways in which Darwinian ideas can lead to productive empirical research, the touchstone of any worthwhile theoretical perspective. While many recent works on cultural evolution adopt a specific theoretical framework, such as dual inheritance theory or human behavioral ecology, Pattern and Process in Cu...

  17. Evolutionary Explanations of Eating Disorders

    Directory of Open Access Journals (Sweden)

    Igor Kardum

    2008-12-01

    Full Text Available This article reviews several most important evolutionary mechanisms that underlie eating disorders. The first part clarifies evolutionary foundations of mental disorders and various mechanisms leading to their development. In the second part selective pressures and evolved adaptations causing contemporary epidemic of obesity as well as differences in dietary regimes and life-style between modern humans and their ancestors are described. Concerning eating disorders, a number of current evolutionary explanations of anorexia nervosa are presented together with their main weaknesses. Evolutionary explanations of eating disorders based on the reproductive suppression hypothesis and its variants derived from kin selection theory and the model of parental manipulation were elaborated. The sexual competition hypothesis of eating disorder, adapted to flee famine hypothesis as well as explanation based on the concept of social attention holding power and the need to belonging were also explained. The importance of evolutionary theory in modern conceptualization and research of eating disorders is emphasized.

  18. A Look at the Factors Influencing Happiness from the Perspective of Evolutionary Psychology%以进化心理学视角解析影响幸福的因素

    Institute of Scientific and Technical Information of China (English)

    莫传玉

    2015-01-01

    The pursuit of happiness has been a perennial topic since ancient times .The concept of happiness has e-volved into a deep and complex diversity .Most scholars even regard happiness as the ultimate goal in life .Drawing on the characteristics of evolutionary psychology , this paper attempts an investigation into the influencing factors of personal happiness and puts forward a paradigm for obtaining it .It is concluded that happiness is not the ultimate goal to be achieved but rather a necessary tool that modulates physiology and provides energy essential to human survival .In addition , since happiness is an indispensable point of reference in human life , every citizen is entitled to it.%从古至今,针对如何追求幸福的话题,已将幸福变成一个深刻而复杂的多元化概念。大部分学者甚至把幸福看作人生的最终目标。本文试图运用“进化心理学”的学科特点,深入探讨影响个人幸福的根源、因素特征,并提出获得幸福的方法。揭示出“幸福”并非作为人生最终目的来实现,而是一个机体调节能量的平衡工具,与个人需要相匹配而存在,是人类生存过程中必不可少的位置参照物,使得每个人都有获得幸福的权利。

  19. The Evolutionary Basis of Honor Cultures.

    Science.gov (United States)

    Nowak, Andrzej; Gelfand, Michele J; Borkowski, Wojciech; Cohen, Dov; Hernandez, Ivan

    2016-01-01

    Around the globe, people fight for their honor, even if it means sacrificing their lives. This is puzzling from an evolutionary perspective, and little is known about the conditions under which honor cultures evolve. We implemented an agent-based model of honor, and our simulations showed that the reliability of institutions and toughness of the environment are crucial conditions for the evolution of honor cultures. Honor cultures survive when the effectiveness of the authorities is low, even in very tough environments. Moreover, the results show that honor cultures and aggressive cultures are mutually dependent in what resembles a predator-prey relationship described in the renowned Lotka-Volterra model. Both cultures are eliminated when institutions are reliable. These results have implications for understanding conflict throughout the world, where Western-based strategies are exported, often unsuccessfully, to contexts of weak institutional authority wherein honor-based strategies have been critical for survival. PMID:26607976

  20. Human Behavior and Cognition in Evolutionary Economics.

    Science.gov (United States)

    Nelson, Richard R

    2011-12-01

    My brand of evolutionary economics recognizes, highlights, that modern economies are always in the process of changing, never fully at rest, with much of the energy coming from innovation. This perspective obviously draws a lot from Schumpeter. Continuing innovation, and the creative destruction that innovation engenders, is driving the system. There are winners and losers in the process, but generally the changes can be regarded as progress. The processes through which economic activity and performance evolve has a lot in common with evolution in biology. In particular, at any time the economy is marked by considerable variety, there are selection forces winnowing on that variety, but also continuing emergence of new ways of doing things and often economic actors. But there also are important differences from biological evolution. In particular, both innovation and selection are to a considerable degree purposive activities, often undertaken on the basis of relatively strong knowledge. PMID:23396655

  1. [Evolutionary medicine: the future looking at the past].

    Science.gov (United States)

    Carvalho, Serafim; Rosado, Margarida

    2008-01-01

    Evolutionary medicine is an emergent basic science that offers new and varied perspectives to the comprehension of the human health and disease, considering them as a result of a gap between our modern lives and the environment where human beings evolve. This work's goals are to understand the importance of the evolutionary theories on concepts of health and disease, providing a new insight on medicine investigation. This bibliography review is based on Medline and PsycINFO articles research between 1996 and 2007 about review and experimental studies published in English, using the key words evolutionary and medicine, psychiatry, psychology, behaviour, health, disease, gene. There were selected forty-five articles based on and with special interest on the authors' practice. There were also consulted some allusive books. The present human genome and phenotypes are essentially Palaeolithic ones: they are not adapted to the modern life style, thus favouring the so called diseases of civilization. Fitting evolutionary strategies, apparently protective ones, when excessive, are the core syndromes of many emotional disruptive behaviours and diseases. Having the stone age's genes, we are obliged to live in the space age. With the evolutionary approach, postmodern medicine is detecting better the vulnerabilities, restrictions, biases, adaptations and maladaptations of human body, its actual diseases and its preventions and treatment.

  2. [Evolutionary medicine: the future looking at the past].

    Science.gov (United States)

    Carvalho, Serafim; Rosado, Margarida

    2008-01-01

    Evolutionary medicine is an emergent basic science that offers new and varied perspectives to the comprehension of the human health and disease, considering them as a result of a gap between our modern lives and the environment where human beings evolve. This work's goals are to understand the importance of the evolutionary theories on concepts of health and disease, providing a new insight on medicine investigation. This bibliography review is based on Medline and PsycINFO articles research between 1996 and 2007 about review and experimental studies published in English, using the key words evolutionary and medicine, psychiatry, psychology, behaviour, health, disease, gene. There were selected forty-five articles based on and with special interest on the authors' practice. There were also consulted some allusive books. The present human genome and phenotypes are essentially Palaeolithic ones: they are not adapted to the modern life style, thus favouring the so called diseases of civilization. Fitting evolutionary strategies, apparently protective ones, when excessive, are the core syndromes of many emotional disruptive behaviours and diseases. Having the stone age's genes, we are obliged to live in the space age. With the evolutionary approach, postmodern medicine is detecting better the vulnerabilities, restrictions, biases, adaptations and maladaptations of human body, its actual diseases and its preventions and treatment. PMID:19331793

  3. Evolutionary comparison between viral lysis rate and latent period.

    Science.gov (United States)

    Bonachela, Juan A; Levin, Simon A

    2014-03-21

    Marine viruses shape the structure of the microbial community. They are, thus, a key determinant of the most important biogeochemical cycles in the planet. Therefore, a correct description of the ecological and evolutionary behavior of these viruses is essential to make reliable predictions about their role in marine ecosystems. The infection cycle, for example, is indistinctly modeled in two very different ways. In one representation, the process is described including explicitly a fixed delay between infection and offspring release. In the other, the offspring are released at exponentially distributed times according to a fixed release rate. By considering obvious quantitative differences pointed out in the past, the latter description is widely used as a simplification of the former. However, it is still unclear how the dichotomy "delay versus rate description" affects long-term predictions of host-virus interaction models. Here, we study the ecological and evolutionary implications of using one or the other approaches, applied to marine microbes. To this end, we use mathematical and eco-evolutionary computational analysis. We show that the rate model exhibits improved competitive abilities from both ecological and evolutionary perspectives in steady environments. However, rate-based descriptions can fail to describe properly long-term microbe-virus interactions. Moreover, additional information about trade-offs between life-history traits is needed in order to choose the most reliable representation for oceanic bacteriophage dynamics. This result affects deeply most of the marine ecosystem models that include viruses, especially when used to answer evolutionary questions. PMID:24361326

  4. 生态经济视角下政府企业污染治理的演化博弈分析%Game Analysis Between Government and Enterprise about the Pollution Treatment from the Perspective of Ecological Economy Evolutionary

    Institute of Scientific and Technical Information of China (English)

    涂小青

    2013-01-01

    本文分析生态经济视角下政府环境监测部门与企业在污染治理过程中的博弈行为。首先分析完全信息静态博弈分析的纳什均衡,然后扩展到群体有限理性下博弈分析,建立了政府监管部门和企业在各自不同的策略选择时的成本和收益函数,运用演化博弈理论研究了博弈模型的稳定性策略。分析结果表明:政府部门应该对企业污染加大监管及惩罚力度;企业应该运用更高的科技水平来降低污染物的产生及污染治理成本;加大政府监管失职处罚,强化政府监管职责;完善环境监管机制,提高政府监管效率,减少监管部门对于企业的监管成本。%This paper analyses ecological economic environment government environmental monitoring depart-ments and enterprises behavior in pollution control in the process of playing the Game. Firstly, the paper analyses the complete information static game theory of Nash equilibrium;and then the paper extends to bounded rationality of game analysis, establishing the government environmental protection department and the enterprises in different strategies when the choice of cost and revenue functions. By using the evolutionary game theory, the paper studies the game model of the stability of the strategy. The game analysis results show that the government should strengthen su-pervision and punishment of enterprise pollution;enterprises should use a higher level of science and technology to reduce the pollutants and the pollution control cost;punishment regulation dereliction of duty should be increased, and government regulatory responsibilities should be improved;the environmental monitoring mechanism should be updated, by improving the efficiency of government regulation, and reducing the cost of monitoring.

  5. Brincadeiras de faz-de-conta em crianças autistas: limites e possibilidades numa perspectiva evolucionista Make-Believe play in autistic children: constraints and possibilities in the evolutionary perspective

    Directory of Open Access Journals (Sweden)

    Carla Silva Fiaes

    2009-12-01

    Full Text Available A constatação da presença universal da brincadeira na infância sugere que tal comportamento deva ter grande valor adaptativo para a espécie. Apesar de universal, a brincadeira sofre interferência do estado desenvolvimental do indivíduo. Crianças com autismo, por exemplo, apresentam dificuldades no brincar, o que nos leva a questionamentos sobre a natureza da sua brincadeira simbólica, se todo faz-de-conta necessariamente inclui teoria da mente e porque um fenômeno considerado universal surge de modo tão atípico no autismo. O artigo discute essas questões à luz da psicologia evolucionista, ilustrando relatos de brincadeiras espontâneas de crianças autistas coletados em instituições educacionais na cidade de Salvador (BA. Os resultados sugerem que os episódios de faz-de-conta envolvem freqüentemente a presença de objetos como apoio para o desenvolvimento da brincadeira. Tal fato está em acordo com a descrição de alguns autores sobre o desenvolvimento do faz-de-conta, com seu início mais sustentado por objetos e independente de metarepresentação.The universal presence of play into the infancy suggests that this behavior must to have a great value adaptative to specie. Although universal, the play receive interference of developmental degree, as children with autism. The difficulties presented by autistic children on the play have came questions about the nature of symbolic play, if all make-believe include theory of mind and why a phenomenon universal emerge of differentiated way in the autism. The article discuss this questions to view of evolutionary psychology, illustrating relates of autistic children's spontaneous play collecting in educational institutions in the Salvador's City. The results suggests that the make believe episodes involves the presence of objects as supportive to developmental of the play. This fact is in accord with the description of some authors about the make-believe developmental, with the

  6. 再集成:一种“模块化陷阱”——基于演化视角的分析%Reintegration. A Type of Modularization Trap --Based on Evolutionary Perspective

    Institute of Scientific and Technical Information of China (English)

    沈于; 安同良

    2012-01-01

    In a modular system, modular division is a ceaseless metabolic process. It is frequently observed that a type of module merges with another over time and the enterprise is excluded from the modular production networks. We call this phenomenon as "reintegration", which is a type of modularization trap to damage the interests of relevant enterprises. It is generally accepted that the merit of modularity is creating option value,which depends on the design risk of the product. By absorbing some viewpoints of technology cycle theory, the paper analyzes the dynamic changes of design risk and discovers the rule that option value declines with technology evolution, thereby explaining the formulation of modular reintegration phenomena. And on that basis, the paper presents a type of evolutionary pattern of modular system. Finally this paper gives suggestions to firms on how to avoid the risk of reintegration.%在模块化系统中,模块的划分是一个不断变化的过程。常常可以观察到:随着时间的推移,一种模块被另一种模块所吞并,不再独立存在,相关厂商被排挤出模块化分工网。我们将这种现象称为"再集成"。"再集成"损害了模块厂商的利益,是一种"模块化陷阱"。一般认为,模块化的优势在于创造"选择权价值",而这依赖于产品的设计风险。本文借鉴了"技术周期理论"的思想,对设计风险做了动态化处理,揭示了"选择权价值"随技术演化而下降的规律,从而解释了"再集成"现象的动因。在此基础上,本文提出了一种模块系统的演化模式,并为企业规避"再集成"风险提出了建议。

  7. Modeling tumor evolutionary dynamics

    Directory of Open Access Journals (Sweden)

    Beatriz eStransky

    2013-02-01

    Full Text Available Tumorigenesis can be seen as an evolutionary process, in which the transformation of a normal cell into a tumor cell involves a number of limiting genetic and epigenetic events, occurring in a series of discrete stages. However, not all mutations in a cell are directly involved in cancer development and it is likely that most of them (passenger mutations do not contribute in any way to tumorigenesis. Moreover, the process of tumor evolution is punctuated by selection of advantageous (driver mutations and clonal expansions. Regarding these driver mutations, it is uncertain how many limiting events are required and / or sufficient to promote a tumorigenic process or what are the values associated with the adaptive advantage of different driver mutations. In spite of the availability of high-quality cancer data, several assumptions about the mechanistic process of cancer initiation and development remain largely untested, both mathematically and statistically. Here we review the development of mathematical/computational models where some assumptions were tested and discuss the impact of these models to the field of tumor biology.

  8. Conserved developmental expression of Fezf in chordates and Drosophila and the origin of the Zona Limitans Intrathalamica (ZLI brain organizer

    Directory of Open Access Journals (Sweden)

    Irimia Manuel

    2010-09-01

    Full Text Available Abstract Background The zona limitans intrathalamica (ZLI and the isthmus organizer (IsO are two major secondary organizers of vertebrate brain development. These organizers are located at the interface of the expression domains of key patterning genes (Fezf-Irx and Otx-Gbx, respectively. To gain insights into the evolutionary origin of the ZLI, we studied Fezf in bilaterians. Results In this paper, we identified a conserved sequence motif (Fezf box in all bilaterians. We report the expression pattern of Fezf in amphioxus and Drosophila and compare it with those of Gbx, Otx and Irx. We found that the relative expression patterns of these genes in vertebrates are fully conserved in amphioxus and flies, indicating that the genetic subdivisions defining the location of both secondary organizers in early vertebrate brain development were probably present in the last common ancestor of extant bilaterians. However, in contrast to vertebrates, we found that Irx-defective flies do not show an affected Fezf expression pattern. Conclusions The absence of expression of the corresponding morphogens from cells at these conserved genetic boundaries in invertebrates suggests that the organizing properties might have evolved specifically in the vertebrate lineage by the recruitment of key morphogens to these conserved genetic locations.

  9. Industrial Applications of Evolutionary Algorithms

    CERN Document Server

    Sanchez, Ernesto; Tonda, Alberto

    2012-01-01

    This book is intended as a reference both for experienced users of evolutionary algorithms and for researchers that are beginning to approach these fascinating optimization techniques. Experienced users will find interesting details of real-world problems, and advice on solving issues related to fitness computation, modeling and setting appropriate parameters to reach optimal solutions. Beginners will find a thorough introduction to evolutionary computation, and a complete presentation of all evolutionary algorithms exploited to solve different problems. The book could fill the gap between the

  10. Analysis of the Industry Spatial Evolution Mechanism and its Determinants from the Perspective of Evolutionary Economic Geography- A Case Study of China's Automobile Industry%演化经济地理学视角下的产业空间演化及其影响因素分析要以中国汽车工业为例

    Institute of Scientific and Technical Information of China (English)

    张永凯; 徐伟

    2014-01-01

    本文以演化经济地理学理论作为分析框架,从演化视角探讨产业空间的演化机制及其影响因素,并以中国汽车工业为例进行实证分析。研究结果发现,改革开放前,政府的汽车产业政策对中国汽车工业空间布局具有决定性的影响;改革开放后,虽然中国汽车工业空间布局在不同阶段的影响因素有所差别,但总体上讲,制度因素、外商投资对中国汽车工业空间布局和演化产生显著性影响。未来,随着市场经济完善和汽车工业技术创新能力提升,市场需求和技术创新影响因素将进一步凸显。%Based on the theoretical framework of evolutionary economic geography, this paper investigates the evolving patterns of China’s manufacturing sectors and their underlying mechanism and determinants from an evolutionary perspective, while taking automobile industry as an empirical case. The results show that government policies had determining effects on the spatial distribution of China's automobile industry before the reforms and opening up. However, the determinants such as institutional factors and foreign investment have significant impacts on the evolution of the spatial configuration of China's automobile industry although the determinants vary from time to time. In the future, with the improvement of market economy and innovation capability of automotive industry, market demand and technological innovation will play an increasingly significant role in reshaping the geography of auto industry in China.

  11. Evolutionary computation for reinforcement learning

    NARCIS (Netherlands)

    S. Whiteson

    2012-01-01

    Algorithms for evolutionary computation, which simulate the process of natural selection to solve optimization problems, are an effective tool for discovering high-performing reinforcement-learning policies. Because they can automatically find good representations, handle continuous action spaces, a

  12. Evolutionary Processes and Mental Deficiency

    Science.gov (United States)

    Spitz, Herman H.

    1973-01-01

    The author hypothesizes that central nervous system damage of deficiency associated with mental retardation affects primarily those cortical processes which developed at a late stage in man's evolutionary history. (Author)

  13. Molluscan Evolutionary Genomics

    Energy Technology Data Exchange (ETDEWEB)

    Simison, W. Brian; Boore, Jeffrey L.

    2005-12-01

    In the last 20 years there have been dramatic advances in techniques of high-throughput DNA sequencing, most recently accelerated by the Human Genome Project, a program that has determined the three billion base pair code on which we are based. Now this tremendous capability is being directed at other genome targets that are being sampled across the broad range of life. This opens up opportunities as never before for evolutionary and organismal biologists to address questions of both processes and patterns of organismal change. We stand at the dawn of a new 'modern synthesis' period, paralleling that of the early 20th century when the fledgling field of genetics first identified the underlying basis for Darwin's theory. We must now unite the efforts of systematists, paleontologists, mathematicians, computer programmers, molecular biologists, developmental biologists, and others in the pursuit of discovering what genomics can teach us about the diversity of life. Genome-level sampling for mollusks to date has mostly been limited to mitochondrial genomes and it is likely that these will continue to provide the best targets for broad phylogenetic sampling in the near future. However, we are just beginning to see an inroad into complete nuclear genome sequencing, with several mollusks and other eutrochozoans having been selected for work about to begin. Here, we provide an overview of the state of molluscan mitochondrial genomics, highlight a few of the discoveries from this research, outline the promise of broadening this dataset, describe upcoming projects to sequence whole mollusk nuclear genomes, and challenge the community to prepare for making the best use of these data.

  14. An amphioxus Gli gene reveals conservation of midline patterning and the evolution of hedgehog signalling diversity in chordates.

    Directory of Open Access Journals (Sweden)

    Sebastian M Shimeld

    Full Text Available BACKGROUND: Hedgehog signalling, interpreted in receiving cells by Gli transcription factors, plays a central role in the development of vertebrate and Drosophila embryos. Many aspects of the signalling pathway are conserved between these lineages, however vertebrates have diverged in at least one key aspect: they have evolved multiple Gli genes encoding functionally-distinct proteins, increasing the complexity of the hedgehog-dependent transcriptional response. Amphioxus is one of the closest living relatives of the vertebrates, having split from the vertebrate lineage prior to the widespread gene duplication prominent in early vertebrate evolution. PRINCIPAL FINDINGS: We show that amphioxus has a single Gli gene, which is deployed in tissues adjacent to sources of hedgehog signalling derived from the midline and anterior endoderm. This shows the duplication and divergence of the Gli gene family, and hence the origin of vertebrate Gli functional diversity, was specific to the vertebrate lineage. However we also show that the single amphioxus Gli gene produces two distinct transcripts encoding different proteins. We utilise three tests of Gli function to examine the transcription regulatory capacities of these different proteins, demonstrating one has activating activity similar to Gli2, while the other acts as a weak repressor, similar to Gli3. CONCLUSIONS: These data show that vertebrates and amphioxus have evolved functionally-similar repertoires of Gli proteins using parallel molecular routes; vertebrates via gene duplication and divergence, and amphioxus via alternate splicing of a single gene. Our results demonstrate that similar functional complexity of intercellular signalling can be achieved via different evolutionary pathways.

  15. Evolutionary computation for trading systems

    OpenAIRE

    Kaucic, Massimiliano

    2008-01-01

    Evolutionary computations, also called evolutionary algorithms, consist of several heuristics, which are able to solve optimization tasks by imitating some aspects of natural evolution. They may use different levels of abstraction, but they are always working on populations of possible solutions for a given task. The basic idea is that if only those individuals of a population which meet a certain selection criteria reproduce, while the remaining individuals die, the population wi...

  16. Counterpunishment revisited: an evolutionary approach

    OpenAIRE

    Wolff, Irenaeus

    2009-01-01

    Evolutionary game theory has shown that in environments characterised by a social-dilemma situation punishment may be an adaptive behaviour. Experimental evidence closely corresponds to this finding but yields contradictory results on the cooperation-enhancing effect of punishment if players are allowed to retaliate against their punishers. The present study sets out to examine the question of whether cooperation will still be part of an evolutionary stable strategy if we allow for counterpun...

  17. Behaviour Trees for Evolutionary Robotics

    OpenAIRE

    Scheper, Kirk Y. W.; Tijmons, Sjoerd; de Visser, Coen C.; de Croon, Guido C. H. E.

    2014-01-01

    Evolutionary Robotics allows robots with limited sensors and processing to tackle complex tasks by means of sensory-motor coordination. In this paper we show the first application of the Behaviour Tree framework to a real robotic platform using the Evolutionary Robotics methodology. This framework is used to improve the intelligibility of the emergent robotic behaviour as compared to the traditional Neural Network formulation. As a result, the behaviour is easier to comprehend and manually ad...

  18. Evolutionary status of Be stars

    Science.gov (United States)

    Zorec, J.; Frémat, Y.; Cidale, L.

    2004-12-01

    Fundamental parameters of nearly 50 field Be stars have been determined. Correcting these parameters from gravity darkening effects induced the fast rotation, we deduced the evolutionary phase of the studied stars. We show that the evolutionary phase at which appear the Be phenomenon is mass dependent: the smaller the stellar mass the elder the phase in the main sequence at which the Be phenomenon seem to appear.

  19. Evolutionary Explanations of Eating Disorders

    OpenAIRE

    Igor Kardum; Asmir Gračanin; Jasna Hudek-Knežević

    2008-01-01

    This article reviews several most important evolutionary mechanisms that underlie eating disorders. The first part clarifies evolutionary foundations of mental disorders and various mechanisms leading to their development. In the second part selective pressures and evolved adaptations causing contemporary epidemic of obesity as well as differences in dietary regimes and life-style between modern humans and their ancestors are described. Concerning eating disorders, a number of current evoluti...

  20. Evolutionary economics and regional policy

    OpenAIRE

    Lambooy, Jan G.; Boschma, Ron

    2001-01-01

    The principal objective of this paper is to formulate some possible links between evolutionary economics and regional policy, a topic that has not (yet) been covered by the literature. We firstly give a brief overview of some issues of regional policy, conceived as a strategy to influence the spatial matrix of economic development. Then, we outline what we take to be the essential arguments and components of evolutionary economics. More in particular, we focus attention on the economic founda...

  1. Shining evolutionary light on human sleep and sleep disorders.

    Science.gov (United States)

    Nunn, Charles L; Samson, David R; Krystal, Andrew D

    2016-01-01

    Sleep is essential to cognitive function and health in humans, yet the ultimate reasons for sleep-i.e. 'why' sleep evolved-remain mysterious. We integrate findings from human sleep studies, the ethnographic record, and the ecology and evolution of mammalian sleep to better understand sleep along the human lineage and in the modern world. Compared to other primates, sleep in great apes has undergone substantial evolutionary change, with all great apes building a sleeping platform or 'nest'. Further evolutionary change characterizes human sleep, with humans having the shortest sleep duration, yet the highest proportion of rapid eye movement sleep among primates. These changes likely reflect that our ancestors experienced fitness benefits from being active for a greater portion of the 24-h cycle than other primates, potentially related to advantages arising from learning, socializing and defending against predators and hostile conspecifics. Perspectives from evolutionary medicine have implications for understanding sleep disorders; we consider these perspectives in the context of insomnia, narcolepsy, seasonal affective disorder, circadian rhythm disorders and sleep apnea. We also identify how human sleep today differs from sleep through most of human evolution, and the implications of these changes for global health and health disparities. More generally, our review highlights the importance of phylogenetic comparisons in understanding human health, including well-known links between sleep, cognitive performance and health in humans. PMID:27470330

  2. Evolutionary genetics of maternal effects.

    Science.gov (United States)

    Wolf, Jason B; Wade, Michael J

    2016-04-01

    Maternal genetic effects (MGEs), where genes expressed by mothers affect the phenotype of their offspring, are important sources of phenotypic diversity in a myriad of organisms. We use a single-locus model to examine how MGEs contribute patterns of heritable and nonheritable variation and influence evolutionary dynamics in randomly mating and inbreeding populations. We elucidate the influence of MGEs by examining the offspring genotype-phenotype relationship, which determines how MGEs affect evolutionary dynamics in response to selection on offspring phenotypes. This approach reveals important results that are not apparent from classic quantitative genetic treatments of MGEs. We show that additive and dominance MGEs make different contributions to evolutionary dynamics and patterns of variation, which are differentially affected by inbreeding. Dominance MGEs make the offspring genotype-phenotype relationship frequency dependent, resulting in the appearance of negative frequency-dependent selection, while additive MGEs contribute a component of parent-of-origin dependent variation. Inbreeding amplifies the contribution of MGEs to the additive genetic variance and, therefore enhances their evolutionary response. Considering evolutionary dynamics of allele frequency change on an adaptive landscape, we show that this landscape differs from the mean fitness surface, and therefore, under some condition, fitness peaks can exist but not be "available" to the evolving population. PMID:26969266

  3. Ecological and evolutionary significance of novel protist lineages.

    Science.gov (United States)

    Del Campo, Javier; Guillou, Laure; Hehenberger, Elisabeth; Logares, Ramiro; López-García, Purificación; Massana, Ramon

    2016-08-01

    Environmental molecular surveys targeting protist diversity have unveiled novel and uncultured lineages in a variety of ecosystems, ranging from completely new high-rank lineages, to new taxa moderately related to previously described organisms. The ecological roles of some of these novel taxa have been studied, showing that in certain habitats they may be responsible for critical environmental processes. Moreover, from an evolutionary perspective they still need to be included in a more accurate and wider understanding of the eukaryotic tree of life. These seminal discoveries promoted the development and use of a wide range of more in-depth culture-independent approaches to access this diversity, from metabarcoding and metagenomics to single cell genomics and FISH. Nonetheless, culturing using classical or innovative approaches is also essential to better characterize this new diversity. Ecologists and evolutionary biologists now face the challenge of apprehending the significance of this new diversity within the eukaryotic tree of life. PMID:26996654

  4. Evolutionary Studies in Business: A Presentation of a New Journal

    Directory of Open Access Journals (Sweden)

    Paloma Fernández Pérez

    2016-01-01

    Full Text Available The Journal of Evolutionary Studies in Business is a new open access journal led by an international interdisciplinary team of scholars located in eight institutions from three continents who wants to attract contributions that help shed light on the new questions, challenges, methodologies and realities, faced by businesses in an evolutionary perspective. The journal calls particularly for review essays that deal with new research topics about business, and provide useful overviews of the key ideas, scholars, and debates about important research topics concerning business and its environment. The strategic areas of interest for submissions from authors are: Management Challenges, Entrepreneurship, Science and Business, Creative Industries, International Business, Business History, and Latin American Businesses. JESB will also publish articles about relevant online resources that contain information of interest to academic scholars and business practitioners.

  5. Steps Towards Operationalising an Evolutionary Archaeological Definition of Culture

    DEFF Research Database (Denmark)

    Riede, Felix

    2011-01-01

    with individual actions. Chaîne opèratoire research, combined with the formal and quantitative identification of variability in individual material culture behaviour allows those traits critical in the social transmission of cultural information to be identified. Once such traits are identified, quantitative...... of culture and that it improves upon traditional, typologically defined techno-complexes. In conclusion, the benefits and limits of such an evolutionary and quantitative definition of culture are discussed.......This paper examines the definition of archaeological cultures/techno-complexes from an evolutionary perspective, in which culture is defined as a system of social information transmission. A formal methodology is presented through which the concept of a culture can be operationalised, at least...

  6. Some Results on Ethnic Conflicts Based on Evolutionary Game Simulation

    CERN Document Server

    Qin, Jun; Wu, Hongrun; Liu, Yuhang; Tong, Xiaonian; Zheng, Bojin

    2014-01-01

    The force of the ethnic separatism, essentially origining from negative effect of ethnic identity, is damaging the stability and harmony of multiethnic countries. In order to eliminate the foundation of the ethnic separatism and set up a harmonious ethnic relationship, some scholars have proposed a viewpoint: ethnic harmony could be promoted by popularizing civic identity. However, this viewpoint is discussed only from a philosophical prospective and still lack supports of scientific evidences. Because ethic group and ethnic identity are products of evolution and ethnic identity is the parochialism strategy under the perspective of game theory, this paper proposes an evolutionary game simulation model to study the relationship between civic identity and ethnic conflict based on evolutionary game theory. The simulation results indicate that: 1) the ratio of individuals with civic identity has a positive association with the frequency of ethnic conflicts; 2) ethnic conflict will not die out by killing all ethni...

  7. Social network reciprocity as a phase transition in evolutionary cooperation

    Science.gov (United States)

    Floría, L. M.; Gracia-Lázaro, C.; Gómez-Gardeñes, J.; Moreno, Y.

    2009-02-01

    In evolutionary dynamics the understanding of cooperative phenomena in natural and social systems has been the subject of intense research during decades. We focus attention here on the so-called “lattice reciprocity” mechanisms that enhance evolutionary survival of the cooperative phenotype in the prisoner’s dilemma game when the population of Darwinian replicators interact through a fixed network of social contacts. Exact results on a “dipole model” are presented, along with a mean-field analysis as well as results from extensive numerical Monte Carlo simulations. The theoretical framework used is that of standard statistical mechanics of macroscopic systems, but with no energy considerations. We illustrate the power of this perspective on social modeling, by consistently interpreting the onset of lattice reciprocity as a thermodynamical phase transition that, moreover, cannot be captured by a purely mean-field approach.

  8. The role of evolutionary biology in research and control of liver flukes in Southeast Asia.

    Science.gov (United States)

    Echaubard, Pierre; Sripa, Banchob; Mallory, Frank F; Wilcox, Bruce A

    2016-09-01

    Stimulated largely by the availability of new technology, biomedical research at the molecular-level and chemical-based control approaches arguably dominate the field of infectious diseases. Along with this, the proximate view of disease etiology predominates to the exclusion of the ultimate, evolutionary biology-based, causation perspective. Yet, historically and up to today, research in evolutionary biology has provided much of the foundation for understanding the mechanisms underlying disease transmission dynamics, virulence, and the design of effective integrated control strategies. Here we review the state of knowledge regarding the biology of Asian liver Fluke-host relationship, parasitology, phylodynamics, drug-based interventions and liver Fluke-related cancer etiology from an evolutionary biology perspective. We consider how evolutionary principles, mechanisms and research methods could help refine our understanding of clinical disease associated with infection by Liver Flukes as well as their transmission dynamics. We identify a series of questions for an evolutionary biology research agenda for the liver Fluke that should contribute to an increased understanding of liver Fluke-associated diseases. Finally, we describe an integrative evolutionary medicine approach to liver Fluke prevention and control highlighting the need to better contextualize interventions within a broader human health and sustainable development framework. PMID:27197053

  9. Neuronal boost to evolutionary dynamics

    Science.gov (United States)

    de Vladar, Harold P.; Szathmáry, Eörs

    2015-01-01

    Standard evolutionary dynamics is limited by the constraints of the genetic system. A central message of evolutionary neurodynamics is that evolutionary dynamics in the brain can happen in a neuronal niche in real time, despite the fact that neurons do not reproduce. We show that Hebbian learning and structural synaptic plasticity broaden the capacity for informational replication and guided variability provided a neuronally plausible mechanism of replication is in place. The synergy between learning and selection is more efficient than the equivalent search by mutation selection. We also consider asymmetric landscapes and show that the learning weights become correlated with the fitness gradient. That is, the neuronal complexes learn the local properties of the fitness landscape, resulting in the generation of variability directed towards the direction of fitness increase, as if mutations in a genetic pool were drawn such that they would increase reproductive success. Evolution might thus be more efficient within evolved brains than among organisms out in the wild. PMID:26640653

  10. Evolutionary engineering for industrial microbiology.

    Science.gov (United States)

    Vanee, Niti; Fisher, Adam B; Fong, Stephen S

    2012-01-01

    Superficially, evolutionary engineering is a paradoxical field that balances competing interests. In natural settings, evolution iteratively selects and enriches subpopulations that are best adapted to a particular ecological niche using random processes such as genetic mutation. In engineering desired approaches utilize rational prospective design to address targeted problems. When considering details of evolutionary and engineering processes, more commonality can be found. Engineering relies on detailed knowledge of the problem parameters and design properties in order to predict design outcomes that would be an optimized solution. When detailed knowledge of a system is lacking, engineers often employ algorithmic search strategies to identify empirical solutions. Evolution epitomizes this iterative optimization by continuously diversifying design options from a parental design, and then selecting the progeny designs that represent satisfactory solutions. In this chapter, the technique of applying the natural principles of evolution to engineer microbes for industrial applications is discussed to highlight the challenges and principles of evolutionary engineering.

  11. Evolutionary Analysis of the Relationship between Economic Growth, Environmental Quality and Resource Scarcity

    NARCIS (Netherlands)

    Bergh, van den Jeroen C.J.M.

    2004-01-01

    The analysis of resource scarcity and environmental pollution in the framework of growth theory during the 1970s has entirely occurred within the domain of standard growth theory. Since the 1980s, growth has been studied from the perspective of evolutionary theories of growth and technical change. T

  12. The Greening of Innovation Systems for Eco-innovation - Towards an Evolutionary Climate Mitigation Policy

    DEFF Research Database (Denmark)

    Andersen, Maj Munch; Foxon, Timothy J.

    2009-01-01

    -innovation policies in important ways. The paper argues that the evolutionary economic perspective entails a new policy rationale which not only puts more emphasis on greening of markets as a means towards reaching climate goals but also shifts the representation of the economy towards a more dynamic one. The policy...

  13. Evolutionary optimization of optical antennas

    CERN Document Server

    Feichtner, Thorsten; Kiunke, Markus; Hecht, Bert

    2012-01-01

    The design of nano-antennas is so far mainly inspired by radio-frequency technology. However, material properties and experimental settings need to be reconsidered at optical frequencies, which entails the need for alternative optimal antenna designs. Here a checkerboard-type, initially random array of gold cubes is subjected to evolutionary optimization. To illustrate the power of the approach we demonstrate that by optimizing the near-field intensity enhancement the evolutionary algorithm finds a new antenna geometry, essentially a split-ring/two-wire antenna hybrid which surpasses by far the performance of a conventional gap antenna by shifting the n=1 split-ring resonance into the optical regime.

  14. Evolutionary Aesthetics and Print Advertising

    Directory of Open Access Journals (Sweden)

    Kamil Luczaj

    2015-06-01

    Full Text Available The article analyzes the extent to which predictions based on the theory of evolutionary aesthetics are utilized by the advertising industry. The purpose of a comprehensive content analysis of print advertising is to determine whether the items indicated by evolutionists such as animals, flowers, certain types of landscapes, beautiful humans, and some colors are part of real advertising strategies. This article has shown that many evolutionary hypotheses (although not all of them are supported by empirical data. Along with these hypotheses, some inferences from Bourdieu’s cultural capital theory were tested. It turned out that advertising uses both biological schemata and cultural patterns to make an image more likable.

  15. Diversity-Guided Evolutionary Algorithms

    DEFF Research Database (Denmark)

    Ursem, Rasmus Kjær

    2002-01-01

    Population diversity is undoubtably a key issue in the performance of evolutionary algorithms. A common hypothesis is that high diversity is important to avoid premature convergence and to escape local optima. Various diversity measures have been used to analyze algorithms, but so far few...... algorithms have used a measure to guide the search. The diversity-guided evolutionary algorithm (DGEA) uses the wellknown distance-to-average-point measure to alternate between phases of exploration (mutation) and phases of exploitation (recombination and selection). The DGEA showed remarkable results...

  16. The ABCs of an evolutionary education science: The academic, behavioral, and cultural implications of an evolutionary approach to education theory and practice

    Science.gov (United States)

    Kauffman, Rick, Jr.

    Calls for improving research-informed policy in education are everywhere. Yet, while there is an increasing trend towards science-based practice, there remains little agreement over which of the sciences to consult and how to organize a collective effort between them. What Education lacks is a general theoretical framework through which policies can be constructed, implemented, and assessed. This dissertation submits that evolutionary theory can provide a suitable framework for coordinating educational policies and practice, and can provide the entire field of education with a clearer sense of how to better manage the learning environment. This dissertation explores two broad paths that outline the conceptual foundations for an Evolutionary Education Science: "Teaching Evolution" and "Using Evolution to Teach." Chapter 1 introduces both of these themes. After describing why evolutionary science is best suited for organizing education research and practice, Chapter 1 proceeds to "teach" an overview of the "evolutionary toolkit"---the mechanisms and principles that underlie the modern evolutionary perspective. The chapter then employs the "toolkit" in examining education from an evolutionary perspective, outlining the evolutionary precepts that can guide theorizing and research in education, describing how educators can "use evolution to teach.". Chapters 2-4 expand on this second theme. Chapters 2 and 3 describe an education program for at-risk 9th and 10th grade students, the Regents Academy, designed entirely with evolutionary principles in mind. The program was rigorously assessed in a randomized control design and has demonstrated success at improving students' academic performance (Chapter 2) and social & behavioral development (Chapter 3). Chapter 4 examines current teaching strategies that underlie effective curriculum-instruction-assessment practices and proposes a framework for organizing successful, evidence-based strategies for neural

  17. EVOLVE : a Bridge between Probability, Set Oriented Numerics and Evolutionary Computation

    CERN Document Server

    Tantar, Alexandru-Adrian; Bouvry, Pascal; Moral, Pierre; Legrand, Pierrick; Coello, Carlos; Schütze, Oliver; EVOLVE 2011

    2013-01-01

    The aim of this book is to provide a strong theoretical support for understanding and analyzing the behavior of evolutionary algorithms, as well as for creating a bridge between probability, set-oriented numerics and evolutionary computation. The volume encloses a collection of contributions that were presented at the EVOLVE 2011 international workshop, held in Luxembourg, May 25-27, 2011, coming from invited speakers and also from selected regular submissions. The aim of EVOLVE is to unify the perspectives offered by probability, set oriented numerics and evolutionary computation. EVOLVE focuses on challenging aspects that arise at the passage from theory to new paradigms and practice, elaborating on the foundations of evolutionary algorithms and theory-inspired methods merged with cutting-edge techniques that ensure performance guarantee factors. EVOLVE is also intended to foster a growing interest for robust and efficient methods with a sound theoretical background. The chapters enclose challenging theoret...

  18. Micro Evolutionary Processes and Adaptation

    Institute of Scientific and Technical Information of China (English)

    SHADMANOV; R; K; RUBAN; I; N; VOROPAEVA; N; L; SHADMANOVA; A; R

    2008-01-01

    It would be well to note that in the absence of clear data about the formation of adaptation systems,or mechanisms of their occurrence,all that is recognized is the realization of the micro evolutionary processes.There is no well-defined connection between information exchange and formation of

  19. Evolutionary models of human personality

    NARCIS (Netherlands)

    Haysom, H.J.; Verweij, C.J.H.; Zietsch, B.P.

    2015-01-01

    Behavioral genetic studies have shown that around a third to a half of the between-individual variation in personality traits can be accounted for by genetic differences between individuals. There is rapidly growing interest in understanding the evolutionary basis of this genetic variation. In this

  20. Evolutionary Computation and its Application

    Institute of Scientific and Technical Information of China (English)

    Licheng Jiao; Lishan Kang; Zhenya He; Tao Xie

    2006-01-01

    @@ On Mar.23,2006,a project in the Major Program of NSFC-"Evolutionary computation and its application",managed by Prof.Licheng Jiao,Prof.Lishan Kang,Prof.Zhenya He,and Prof.Tao Xie,passed its Final Qualification Process and was evaluated as Excellent.

  1. Evolutionary dynamics of mammalian karyotypes

    Directory of Open Access Journals (Sweden)

    Carlo Alberto Redi

    2012-12-01

    Full Text Available This special volume of Cytogenetic and Genome Research (edited by Roscoe Stanyon, University of Florence and Alexander Graphodatsky, Siberian division of the Russian Academy of Sciences is dedicated to the fascinating long search of the forces behind the evolutionary dynamics of mammalian karyotypes, revealed after the hypotonic miracle of the 1950s....

  2. The Challange of Evolutionary Learning.

    Science.gov (United States)

    Banathy, Bela H.

    Emerging educational needs in the interdependent world of the Information Age are explored. The current global human predicament in the historical context of the evolution of human systems is examined. A description is given of a systems view of the current evolutionary stage and the new educational needs of the Information Age that can be derived…

  3. Genetical Genomics for Evolutionary Studies

    NARCIS (Netherlands)

    Prins, J.C.P.; Smant, G.; Jansen, R.C.

    2012-01-01

    enetical genomics combines acquired high-throughput genomic data with genetic analysis. In this chapter, we discuss the application of genetical genomics for evolutionary studies, where new high-throughput molecular technologies are combined with mapping quantitative trait loci (QTL) on the genome i

  4. Evolutionary trends in directional hearing

    DEFF Research Database (Denmark)

    Carr, Catherine E; Christensen-Dalsgaard, Jakob

    2016-01-01

    Tympanic hearing is a true evolutionary novelty that arose in parallel within early tetrapods. We propose that in these tetrapods, selection for sound localization in air acted upon pre-existing directionally sensitive brainstem circuits, similar to those in fishes. Auditory circuits in birds and...

  5. Evolutionary Psychology and Intelligence Research

    Science.gov (United States)

    Kanazawa, Satoshi

    2010-01-01

    This article seeks to unify two subfields of psychology that have hitherto stood separately: evolutionary psychology and intelligence research/differential psychology. I suggest that general intelligence may simultaneously be an evolved adaptation and an individual-difference variable. Tooby and Cosmides's (1990a) notion of random quantitative…

  6. The evolutionary differentiation of two histone H2A.Z variants in chordates (H2A.Z-1 and H2A.Z-2) is mediated by a stepwise mutation process that affects three amino acid residues

    OpenAIRE

    Ausió Juan; Ishibashi Toyotaka; Dryhurst Deanna; González-Romero Rodrigo; Eirín-López José M

    2009-01-01

    Abstract Background The histone H2A family encompasses the greatest number of core histone variants of which the replacement variant H2A.Z is currently one of the most heavily studied. No clear mechanism for the functional variability that H2A.Z imparts to chromatin has yet been proposed. While most of the past studies have referred to H2A.Z generically as a single protein, in vertebrates it is a mixture of two protein forms H2A.Z-1 (previously H2A.Z) and H2A.Z-2 (previously H2A.F/Z or H2A.V)...

  7. The role of eco-evolutionary experience in invasion success

    Directory of Open Access Journals (Sweden)

    Wolf-Christian Saul

    2013-06-01

    Full Text Available Invasion ecology has made considerable progress in identifying specific mechanisms that potentially determine success and failure of biological invasions. Increasingly, efforts are being made to interrelate or even synthesize the growing number of hypotheses in order to gain a more comprehensive and integrative understanding of invasions. We argue that adopting an eco-evolutionary perspective on invasions is a promising approach to achieve such integration. It emphasizes the evolutionary antecedents of invasions, i.e. the species’ evolutionary legacy and its role in shaping novel biotic interactions that arise due to invasions. We present a conceptual framework consisting of five hypothetical scenarios about the influence of so-called ‘eco-evolutionary experience’ in resident native and invading non-native species on invasion success, depending on the type of ecological interaction (predation, competition, mutualism, and commensalism. We show that several major ecological invasion hypotheses, including ‘enemy release’, ‘EICA’, ‘novel weapons’, ‘naïve prey’, ‘new associations’, ‘missed mutualisms’ and ‘Darwin’s naturalization hypothesis’ can be integrated into this framework by uncovering their shared implicit reference to the concept of eco-evolutionary experience. We draft a routine for the assessment of eco-evolutionary experience in native and non-native species using a food web-based example and propose two indices (xpFocal index and xpResidents index for the actual quantification of eco-evolutionary experience. Our study emphasizes the explanatory potential of an eco-evolutionary perspective on biological invasions.

  8. Perceived consequences of evolution: College students perceive negative personal and social impact in evolutionary theory

    Science.gov (United States)

    Brem, Sarah K.; Ranney, Michael; Schindel, Jennifer

    2003-03-01

    Evolutionary science has consequences for individuals and society, ranging from the way we interpret human behavior to our notions of spirituality and the purpose of our existence. Popular portrayals of evolution depict a paradoxical theory, a source of knowledge and human connections, but also a threat to our humanity and freedom. Using quantitative and qualitative methodology, we examined how college-educated adults (n = 135) from diverse ethnic and religious backgrounds perceive the impact of evolutionary theory on individuals and society. We identified a continuum of perspectives, ranging from strong creationist to strong evolutionist. Using the model of knowledge as an ecology (Demastes, Good, & Peebles, Science Education, 79, 637-666, 1995; Nardi & O'Day, Information ecologies: Using technology with heart, MIT Press, Cambridge, MA, 1999), we examined the relationships among participants' beliefs, their perceptions regarding the social and personal impact of evolutionary theory, their prior exposure to and knowledge of evolutionary theory, and their opinions regarding the teaching of evolution. Evolutionists and creationists differed in their prior exposure to evolutionary theory, and their opinions about some aspects of teaching, but showed striking similarities regarding perceived impact. All groups viewed the consequences of accepting evolutionary principles in a way that might be considered undesirable: increased selfishness and racism, decreased spirituality, and a decreased sense of purpose and self-determination. From a science education perspective, this one-sided interpretation is troublesome because it runs counter to the available evidence and theories in evolutionary science, and we consider ways of fostering more balanced presentation and appraisal of evolutionary theory.

  9. Evolutionary origins of C-terminal (GPPn 3-hydroxyproline formation in vertebrate tendon collagen.

    Directory of Open Access Journals (Sweden)

    David M Hudson

    Full Text Available Approximately half the proline residues in fibrillar collagen are hydroxylated. The predominant form is 4-hydroxyproline, which helps fold and stabilize the triple helix. A minor form, 3-hydroxyproline, still has no clear function. Using peptide mass spectrometry, we recently revealed several previously unknown molecular sites of 3-hydroxyproline in fibrillar collagen chains. In fibril-forming A-clade collagen chains, four new partially occupied 3-hydroxyproline sites were found (A2, A3, A4 and (GPPn in addition to the fully occupied A1 site at Pro986. The C-terminal (GPPn motif has five consecutive GPP triplets in α1(I, four in α2(I and three in α1(II, all subject to 3-hydroxylation. The evolutionary origins of this substrate sequence were investigated by surveying the pattern of its 3-hydroxyproline occupancy from early chordates through amphibians, birds and mammals. Different tissue sources of type I collagen (tendon, bone and skin and type II collagen (cartilage and notochord were examined by mass spectrometry. The (GPPn domain was found to be a major substrate for 3-hydroxylation only in vertebrate fibrillar collagens. In higher vertebrates (mouse, bovine and human, up to five 3-hydroxyproline residues per (GPPn motif were found in α1(I and four in α2(I, with an average of two residues per chain. In vertebrate type I collagen the modification exhibited clear tissue specificity, with 3-hydroxyproline prominent only in tendon. The occupancy also showed developmental changes in Achilles tendon, with increasing 3-hydroxyproline levels with age. The biological significance is unclear but the level of 3-hydroxylation at the (GPPn site appears to have increased as tendons evolved and shows both tendon type and developmental variations within a species.

  10. The retinoic acid signaling pathway regulates anterior/posterior patterning in the nerve cord and pharynx of amphioxus, a chordate lacking neural crest

    Science.gov (United States)

    Escriva, Hector; Holland, Nicholas D.; Gronemeyer, Hinrich; Laudet, Vincent; Holland, Linda Z.

    2002-01-01

    Amphioxus, the closest living invertebrate relative of the vertebrates, has a notochord, segmental axial musculature, pharyngeal gill slits and dorsal hollow nerve cord, but lacks neural crest. In amphioxus, as in vertebrates, exogenous retinoic acid (RA) posteriorizes the embryo. The mouth and gill slits never form, AmphiPax1, which is normally downregulated where gill slits form, remains upregulated and AmphiHox1 expression shifts anteriorly in the nerve cord. To dissect the role of RA signaling in patterning chordate embryos, we have cloned the single retinoic acid receptor (AmphiRAR), retinoid X receptor (AmphiRXR) and an orphan receptor (AmphiTR2/4) from amphioxus. AmphiTR2/4 inhibits AmphiRAR-AmphiRXR-mediated transactivation in the presence of RA by competing for DR5 or IR7 retinoic acid response elements (RAREs). The 5' untranslated region of AmphiTR2/4 contains an IR7 element, suggesting possible auto- and RA-regulation. The patterns of AmphiTR2/4 and AmphiRAR expression during embryogenesis are largely complementary: AmphiTR2/4 is strongly expressed in the cerebral vesicle (homologous to the diencephalon plus anterior midbrain), while AmphiRAR expression is high in the equivalent of the hindbrain and spinal cord. Similarly, while AmphiTR2/4 is expressed most strongly in the anterior and posterior thirds of the endoderm, the highest AmphiRAR expression is in the middle third. Expression of AmphiRAR is upregulated by exogenous RA and completely downregulated by the RA antagonist BMS009. Moreover, BMS009 expands the pharynx posteriorly; the first three gill slit primordia are elongated and shifted posteriorly, but do not penetrate, and additional, non-penetrating gill slit primordia are induced. Thus, in an organism without neural crest, initiation and penetration of gill slits appear to be separate events mediated by distinct levels of RA signaling in the pharyngeal endoderm. Although these compounds have little effect on levels of AmphiTR2/4 expression, RA

  11. OPTIMISED RANDOM MUTATIONS FOR EVOLUTIONARY ALGORITHMS

    Directory of Open Access Journals (Sweden)

    Sean McGerty

    2014-07-01

    Full Text Available To demonstrate our approaches we will use Sudoku puzzles, which are an excellent test bed for evolutionary algorithms. The puzzles are accessible enough for people to enjoy. However the more complex puzzles require thousands of iterations before an evolutionary algorithm finds a solution. If we were attempting to compare evolutionary algorithms we could count their iterations to solution as an indicator of relative efficiency. Evolutionary algorithms however include a process of random mutation for solution candidates. We will show that by improving the random mutation behaviours we were able to solve problems with minimal evolutionary optimisation. Experiments demonstrated the random mutation was at times more effective at solving the harder problems than the evolutionary algorithms. This implies that the quality of random mutation may have a significant impact on the performance of evolutionary algorithms with Sudoku puzzles. Additionally this random mutation may hold promise for reuse in hybrid evolutionary algorithm behaviours.

  12. Strategic alliances : Alliance contracting and trust in an evolutionary perspective

    NARCIS (Netherlands)

    Alders, Ben; Berendsen, Gerard; Pieters, Ineke

    2009-01-01

    In this paper we will identify the contract dimensions of alliance contracts directed at joint development of new products or services. We will determine to what extent these contract dimensions are adaptable to future needs and insights. We will also provide insight into the contingency of these ad

  13. Nursing leadership within the NHS: an evolutionary perspective.

    Science.gov (United States)

    Sherring, Simon

    Effective leadership is crucial to the delivery of quality NHS care, particularly in the current economic climate. These are unprecedented times for the NHS; at no other time in its life has the need for leadership been greater. It is hard to define nursing leadership, with roles becoming increasingly complex. Although there has been much invested in leadership training, NHS guidance has suggested the service has only just begun to understand the importance of leadership. There is unparalleled change in the NHS; nurses are being asked to be innovators and entrepreneurs. In this article, the author considers what leadership is, and stresses the need for it to continue evolving to meet the changing demands of the NHS.

  14. Evolutionary and anthropological perspectives on optimal foraging in obesogenic environments.

    Science.gov (United States)

    Lieberman, Leslie Sue

    2006-07-01

    The nutrition transition has created an obesogenic environment resulting in a growing obesity pandemic. An optimal foraging approach provides cost/benefit models of cognitive, behavioral and physiological strategies that illuminate the causes of caloric surfeit and consequent obesity in current environments of abundant food cues; easy-access and reliable food patches; low processing costs and enormous variety of energy-dense foods. Experimental and naturalistic observations demonstrate that obesogenic environments capitalize on human proclivities by displaying colorful advertising, supersizing meals, providing abundant variety, increasing convenience, and utilizing distractions that impede monitoring of food portions during consumption. The globalization of fast foods propels these trends. PMID:16806580

  15. The Elevated Susceptibility to Diabetes in India: An Evolutionary Perspective.

    Science.gov (United States)

    Wells, Jonathan C K; Pomeroy, Emma; Walimbe, Subhash R; Popkin, Barry M; Yajnik, Chittaranjan S

    2016-01-01

    India has rapidly become a "diabetes capital" of the world, despite maintaining high rates of under-nutrition. Indians develop diabetes at younger age and at lower body weights than other populations. Here, we interpret these characteristics in terms of a "capacity-load" model of glucose homeostasis. Specifically, we assume that glycemic control depends on whether the body's "metabolic capacity," referring to traits, such as pancreatic insulin production and muscle glucose clearance, is able to resolve the "metabolic load" generated by high levels of body fat, high dietary glycemic load, and sedentary behavior. We employ data from modern cohorts to support the model and the interpretation that elevated diabetic risk among Indian populations results from the high metabolic load imposed by westernized lifestyles acting on a baseline of low metabolic capacity. We attribute this low metabolic capacity to the low birth weight characteristic of Indian populations, which is associated with short stature and low lean mass in adult life. Using stature as a marker of metabolic capacity, we review archeological and historical evidence to highlight long-term declines in Indian stature associated with adaptation to several ecological stresses. Underlying causes may include increasing population density following the emergence of agriculture, the spread of vegetarian diets, regular famines induced by monsoon failure, and the undermining of agricultural security during the colonial period. The reduced growth and thin physique that characterize Indian populations elevate susceptibility to truncal obesity, and increase the metabolic penalties arising from sedentary behavior and high glycemic diets. Improving metabolic capacity may require multiple generations; in the meantime, efforts to reduce the metabolic load will help ameliorate the situation. PMID:27458578

  16. An evolutionary ecological perspective on demographic transitions: modeling multiple currencies.

    Science.gov (United States)

    Low, Bobbi S; Simon, Carl P; Anderson, Kermyt G

    2002-01-01

    Life history theory postulates tradeoffs of current versus future reproduction; today women face evolutionarily novel versions of these tradeoffs. Optimal age at first birth is the result of tradeoffs in fertility and mortality; ceteris paribus, early reproduction is advantageous. Yet modern women in developed nations experience relatively late first births; they appear to be trading off socioeconomic status and the paths to raised SES, education and work, against early fertility. Here, [1] using delineating parameter values drawn from data in the literature, we model these tradeoffs to determine how much socioeconomic advantage will compensate for delayed first births and lower lifetime fertility; and [2] we examine the effects of work and education on women's lifetime and age-specific fertility using data from seven cohorts in the Panel Study of Income Dynamics (PSID). PMID:11891931

  17. Dopamine in Socioecological and Evolutionary Perspectives: Implications for Psychiatric Disorders

    OpenAIRE

    Yoshie eYamaguchi; Young-A eLee; Yukiori eGoto

    2015-01-01

    Dopamine (DA) transmission in brain areas such as the prefrontal cortex (PFC) and nucleus accumbens (NAcc) plays important roles in cognitive and affective function. As such, DA deficits have been implicated in a number of psychiatric disorders such as schizophrenia and attention deficit/hyperactivity disorder (ADHD). Accumulating evidence suggests that DA is also involved in social behavior of animals and humans. Although most animals organize and live in social groups, how the DA system f...

  18. Dopamine in socioecological and evolutionary perspectives: implications for psychiatric disorders

    OpenAIRE

    Yamaguchi, Yoshie; Lee, Young-A; Goto, Yukiori

    2015-01-01

    Dopamine (DA) transmission in brain areas such as the prefrontal cortex (PFC) and nucleus accumbens (NAcc) plays important roles in cognitive and affective function. As such, DA deficits have been implicated in a number of psychiatric disorders such as schizophrenia and attention deficit/hyperactivity disorder (ADHD). Accumulating evidence suggests that DA is also involved in social behavior of animals and humans. Although most animals organize and live in social groups, how the DA system fun...

  19. The Elevated Susceptibility to Diabetes in India: An Evolutionary Perspective

    Science.gov (United States)

    Wells, Jonathan C. K.; Pomeroy, Emma; Walimbe, Subhash R.; Popkin, Barry M.; Yajnik, Chittaranjan S.

    2016-01-01

    India has rapidly become a “diabetes capital” of the world, despite maintaining high rates of under-nutrition. Indians develop diabetes at younger age and at lower body weights than other populations. Here, we interpret these characteristics in terms of a “capacity–load” model of glucose homeostasis. Specifically, we assume that glycemic control depends on whether the body’s “metabolic capacity,” referring to traits, such as pancreatic insulin production and muscle glucose clearance, is able to resolve the “metabolic load” generated by high levels of body fat, high dietary glycemic load, and sedentary behavior. We employ data from modern cohorts to support the model and the interpretation that elevated diabetic risk among Indian populations results from the high metabolic load imposed by westernized lifestyles acting on a baseline of low metabolic capacity. We attribute this low metabolic capacity to the low birth weight characteristic of Indian populations, which is associated with short stature and low lean mass in adult life. Using stature as a marker of metabolic capacity, we review archeological and historical evidence to highlight long-term declines in Indian stature associated with adaptation to several ecological stresses. Underlying causes may include increasing population density following the emergence of agriculture, the spread of vegetarian diets, regular famines induced by monsoon failure, and the undermining of agricultural security during the colonial period. The reduced growth and thin physique that characterize Indian populations elevate susceptibility to truncal obesity, and increase the metabolic penalties arising from sedentary behavior and high glycemic diets. Improving metabolic capacity may require multiple generations; in the meantime, efforts to reduce the metabolic load will help ameliorate the situation. PMID:27458578

  20. Emergence, geography & networks of the Indian IT industry : evolutionary perspectives

    OpenAIRE

    Täube, Florian Arun

    2007-01-01

    The Indian IT industry has received great attention. Although most studies cover South Indian locations, clustering has rarely been a topic. This study focuses on Bangalore addressing questions related to Bangalore’s successful development and lessons thereof for other regions in and outside India. The approach pertains to economic geography and international business; hypotheses have been developed from a multi-disciplinary literature survey and interview fieldwork in Bangalore. I emphasize ...

  1. Dopamine in Socioecological and Evolutionary Perspectives: Implications for Psychiatric Disorders

    Directory of Open Access Journals (Sweden)

    Yoshie eYamaguchi

    2015-06-01

    Full Text Available Dopamine (DA transmission in brain areas such as the prefrontal cortex (PFC and nucleus accumbens (NAcc plays important roles in cognitive and affective function. As such, DA deficits have been implicated in a number of psychiatric disorders such as schizophrenia and attention deficit/hyperactivity disorder (ADHD. Accumulating evidence suggests that DA is also involved in social behavior of animals and humans. Although most animals organize and live in social groups, how the DA system functions in such social groups of animals, and its dysfunction causes compromises in the groups has remained less understood. Here we propose that alterations of DA signaling and associated genetic variants and behavioral phenotypes, which have been normally considered as deficits in investigation at an individual level, may not necessarily yield disadvantages, and even work advantageously, depending on social contexts in subjects with such DA alterations living in social groups. This hypothesis could provide a novel insight into our understanding of the biological mechanisms of psychiatric disorders, and a potential explanation that disadvantageous phenotypes associated with DA deficits in psychiatric disorders have remained in humans through evolution.

  2. Human locomotion and heat loss: an evolutionary perspective.

    Science.gov (United States)

    Lieberman, Daniel E

    2015-01-01

    Humans are unique in many respects including being furless, striding bipeds that excel at walking and running long distances in hot conditions. This review summarizes what we do and do not know about the evolution of these characteristics, and how they are related. Although many details remain poorly known, the first hominins (species more closely related to humans than to chimpanzees) apparently diverged from the chimpanzee lineage because of selection for bipedal walking, probably because it improved their ability to forage efficiently. However, because bipedal hominins are necessarily slow runners, early hominins in open habitats likely benefited from improved abilities to dump heat in order to forage safely during times of peak heat when predators were unable to hunt them. Endurance running capabilities evolved later, probably as adaptations for scavenging and then hunting. If so, then there would have been strong selection for heat-loss mechanisms, especially sweating, to persistence hunt, in which hunters combine endurance running and tracking to drive their prey into hyperthermia. As modern humans dispersed into a wide range of habitats over the last few hundred thousand years, recent selection has helped populations cope better with a broader range of locomotor and thermoregulatory challenges, but all humans remain essentially adapted for long distance locomotion rather than speed, and to dump rather than retain heat. PMID:25589265

  3. Comparative anatomy and physiology of myrmecophytes: ecological and evolutionary perspectives

    OpenAIRE

    González-Teuber, Marcia

    2015-01-01

    Marcia González-Teuber,1 Martin Heil21Department of Biology, Universidad de La Serena, La Serena, Chile; 2Department of Genetic Engineering, CINVESTAV, Irapuato, Guanajuato, MéxicoAbstract: Ant–plant interactions are classic examples of defensive mutualisms and have served as model systems to study the ecology and evolution of mutualisms since the 19th century. Ant–plant mutualisms range in specificity from myrmecophilic (ant-loving) plants, which att...

  4. Alarm pheromone processing in the ant brain: an evolutionary perspective

    Directory of Open Access Journals (Sweden)

    Makoto Mizunami

    2010-06-01

    Full Text Available Social insects exhibit sophisticated communication by means of pheromones, one example of which is the use of alarm pheromones to alert nestmates for colony defense. We review recent advances in the understanding of the processing of alarm pheromone information in the ant brain. We found that information about formic acid and n-undecane, alarm pheromone components, is processed in a set of specific glomeruli in the antennal lobe of the ant Camponotus obscuripes. Alarm pheromone information is then transmitted, via projection neurons, to the lateral horn and the calyces of the mushroom body of the protocerebrum. In the lateral horn, we found a specific area where terminal boutons of alarm pheromone-sensitive projection neurons are more densely distributed than in the rest of the lateral horn. Some neurons in the protocerebrum responded specifically to formic acid or n-undecane and they may participate in the control of behavioral responses to each pheromone component. Other neurons, especially those originating from the mushroom body lobe, responded also to non-pheromonal odors and may play roles in integration of pheromonal and non-pheromonal signals. We found that a class of neurons receive inputs in the lateral horn and the mushroom body lobe and terminate in a variety of premotor areas. These neurons may participate in the control of aggressive behavior, which is sensitized by alarm pheromones and is triggered by non-pheromonal sensory stimuli associated with a potential enemy. We propose that the alarm pheromone processing system has evolved by differentiation of a part of general odor processing system.

  5. Hypermedia Genes An Evolutionary Perspective on Concepts, Models, and Architectures

    CERN Document Server

    Guimarães, Nuno

    2009-01-01

    The design space of information services evolved from seminal works through a set of prototypical hypermedia systems and matured in open and widely accessible web-based systems. The original concepts of hypermedia systems are now expressed in different forms and shapes. The first works on hypertext invented the term itself, laid out the foundational concept of association or link, and highlighted navigation as the core paradigm for the future information systems. The first engineered systems demonstrated architectural requirements and models and fostered the emergence of the conceptual model r

  6. The evolutionary physiology of animal flight: paleobiological and present perspectives.

    Science.gov (United States)

    Dudley, R

    2000-01-01

    Recent geophysical analyses suggest the presence of a late Paleozoic oxygen pulse beginning in the late Devonian and continuing through to the late Carboniferous. During this period, plant terrestrialization and global carbon deposition resulted in a dramatic increase in atmospheric oxygen levels, ultimately yielding concentrations potentially as high as 35% relative to the contemporary value of 21%. Such hyperoxia of the late Paleozoic atmosphere may have physiologically facilitated the initial evolution of insect flight metabolism. Widespread gigantism in late Paleozoic insects and other arthropods is also consistent with enhanced oxygen flux within diffusion-limited tracheal systems. Because total atmospheric pressure increases with increased oxygen partial pressure, concurrently hyperdense conditions would have augmented aerodynamic force production in early forms of flying insects. By the late Permian, evolution of decompositional microbial and fungal communities, together with disequilibrium in rates of carbon deposition, gradually reduced oxygen concentrations to values possibly as low as 15%. The disappearance of giant insects by the end of the Permian is consistent with extinction of these taxa for reasons of asphyxiation on a geological time scale. As with winged insects, the multiple historical origins of vertebrate flight in the late Jurassic and Cretaceous correlate temporally with periods of elevated atmospheric oxygen. Much discussion of flight performance in Archaeopteryx assumes a contemporary atmospheric composition. Elevated oxygen levels in the mid- to late Mesozoic would, however, have facilitated aerodynamic force production and enhanced muscle power output for ancestral birds, as well as for precursors to bats and pterosaurs.

  7. The evolutionary physiology of animal flight: paleobiological and present perspectives.

    Science.gov (United States)

    Dudley, R

    2000-01-01

    Recent geophysical analyses suggest the presence of a late Paleozoic oxygen pulse beginning in the late Devonian and continuing through to the late Carboniferous. During this period, plant terrestrialization and global carbon deposition resulted in a dramatic increase in atmospheric oxygen levels, ultimately yielding concentrations potentially as high as 35% relative to the contemporary value of 21%. Such hyperoxia of the late Paleozoic atmosphere may have physiologically facilitated the initial evolution of insect flight metabolism. Widespread gigantism in late Paleozoic insects and other arthropods is also consistent with enhanced oxygen flux within diffusion-limited tracheal systems. Because total atmospheric pressure increases with increased oxygen partial pressure, concurrently hyperdense conditions would have augmented aerodynamic force production in early forms of flying insects. By the late Permian, evolution of decompositional microbial and fungal communities, together with disequilibrium in rates of carbon deposition, gradually reduced oxygen concentrations to values possibly as low as 15%. The disappearance of giant insects by the end of the Permian is consistent with extinction of these taxa for reasons of asphyxiation on a geological time scale. As with winged insects, the multiple historical origins of vertebrate flight in the late Jurassic and Cretaceous correlate temporally with periods of elevated atmospheric oxygen. Much discussion of flight performance in Archaeopteryx assumes a contemporary atmospheric composition. Elevated oxygen levels in the mid- to late Mesozoic would, however, have facilitated aerodynamic force production and enhanced muscle power output for ancestral birds, as well as for precursors to bats and pterosaurs. PMID:10845087

  8. Evolutionary neurocontrollers for autonomous mobile robots.

    Science.gov (United States)

    Floreano, D; Mondada, F

    1998-10-01

    In this article we describe a methodology for evolving neurocontrollers of autonomous mobile robots without human intervention. The presentation, which spans from technological and methodological issues to several experimental results on evolution of physical mobile robots, covers both previous and recent work in the attempt to provide a unified picture within which the reader can compare the effects of systematic variations on the experimental settings. After describing some key principles for building mobile robots and tools suitable for experiments in adaptive robotics, we give an overview of different approaches to evolutionary robotics and present our methodology. We start reviewing two basic experiments showing that different environments can shape very different behaviours and neural mechanisms under very similar selection criteria. We then address the issue of incremental evolution in two different experiments from the perspective of changing environments and robot morphologies. Finally, we investigate the possibility of evolving plastic neurocontrollers and analyse an evolved neurocontroller that relies on fast and continuously changing synapses characterized by dynamic stability. We conclude by reviewing the implications of this methodology for engineering, biology, cognitive science and artificial life, and point at future directions of research.

  9. An Evolutionary Framework for 3-SAT Problems

    OpenAIRE

    Borgulya, István

    2003-01-01

    In this paper we present a new evolutionary framework for 3-SAT. This method can be divided into three stages, where each stage is an evolutionary algorithm. The first stage improves the quality of the initial population. The second stage improves the speed of the algorithm periodically generating new solutions. The 3rd stage is a hybrid evolutionary algorithm, which improves the solutions with a local search. The key points of our algorithm are the evolutionary framework and the mutation ope...

  10. From computers to cultivation: reconceptualizing evolutionary psychology

    OpenAIRE

    Louise eBarrett; Thomas ePollet; Gert eStulp

    2014-01-01

    Does evolutionary theorizing have a role in psychology? This is a more contentious issue than one might imagine, given that as evolved creatures, the answer must surely be yes. The contested nature of evolutionary psychology lies not in our status as evolved beings, but in the extent to which evolutionary ideas add value to studies of human behaviour, and the rigour with which these ideas are tested. This, in turn, is linked to the framework in which particular evolutionary ideas are situated...

  11. From computers to cultivation: reconceptualizing evolutionary psychology

    OpenAIRE

    Barrett, Louise; Pollet, Thomas V.; Stulp, Gert

    2014-01-01

    Does evolutionary theorizing have a role in psychology? This is a more contentious issue than one might imagine, given that, as evolved creatures, the answer must surely be yes. The contested nature of evolutionary psychology lies not in our status as evolved beings, but in the extent to which evolutionary ideas add value to studies of human behavior, and the rigor with which these ideas are tested. This, in turn, is linked to the framework in which particular evolutionary ideas are situated....

  12. The citation field of evolutionary economics

    NARCIS (Netherlands)

    Dolfsma, Wilfred; Leydesdorff, Loet

    2010-01-01

    Evolutionary economics has developed into an academic field of its own, institutionalized around, amongst others, the Journal of Evolutionary Economics (JEE). This paper analyzes the way and extent to which evolutionary economics has become an interdisciplinary journal, as its aim was: a journal tha

  13. Intuitive vs Analytical Thinking: Four Perspectives

    Science.gov (United States)

    Leron, Uri; Hazzan, Orit

    2009-01-01

    This article is an attempt to place mathematical thinking in the context of more general theories of human cognition. We describe and compare four perspectives--mathematics, mathematics education, cognitive psychology, and evolutionary psychology--each offering a different view on mathematical thinking and learning and, in particular, on the…

  14. Evolutionary Approaches to Expensive Optimisation

    Directory of Open Access Journals (Sweden)

    Maumita Bhattacharya

    2013-03-01

    Full Text Available Surrogate assisted evolutionary algorithms (EA are rapidly gaining popularity where applications of EA in complex real world problem domains are concerned. Although EAs are powerful global optimizers, finding optimal solution to complex high dimensional, multimodal problems often require very expensive fitness function evaluations. Needless to say, this could brand any population-based iterative optimization technique to be the most crippling choice to handle such problems. Use of approximate model or surrogates provides a much cheaper option. However, naturally this cheaper option comes with its own price! This paper discusses some of the key issues involved with use of approximation in evolutionary algorithm, possible best practices and solutions. Answers to the following questions have been sought: what type of fitness approximation to be used; which approximation model to use; how to integrate the approximation model in EA; how much approximation to use; and how to ensure reliable approximation.

  15. Evolutionary Games and Social Conventions

    DEFF Research Database (Denmark)

    Hansen, Pelle Guldborg

    2007-01-01

    in Aumann (1976) and which, together with the assumptions of perfect rationality, came to be defining of classical game theory. However, classical game theory is currently undergoing severe crisis as a tool for exploring social phenomena; a crisis emerging from the problem of equilibrium selection around...... which any theory of convention must revolve. In response, the so-called evolutionary turn has developed. While retaining the broad framework, in which games are described in terms of strategies and payoffs, this marks a transition from the classical assumptions of perfect rationality and common...... knowledge to assumptions characterising agents as conditioned for playing certain strategies upon the population of which evolutionary processes operate. By providing accounts of equilibrium selection and stability properties of behaviours, the resulting frameworks have been brought to work as well...

  16. Evolutionary model of stock markets

    Science.gov (United States)

    Kaldasch, Joachim

    2014-12-01

    The paper presents an evolutionary economic model for the price evolution of stocks. Treating a stock market as a self-organized system governed by a fast purchase process and slow variations of demand and supply the model suggests that the short term price distribution has the form a logistic (Laplace) distribution. The long term return can be described by Laplace-Gaussian mixture distributions. The long term mean price evolution is governed by a Walrus equation, which can be transformed into a replicator equation. This allows quantifying the evolutionary price competition between stocks. The theory suggests that stock prices scaled by the price over all stocks can be used to investigate long-term trends in a Fisher-Pry plot. The price competition that follows from the model is illustrated by examining the empirical long-term price trends of two stocks.

  17. Evolutionary biology and life histories

    OpenAIRE

    Brown, C R; Thomson, D. L.

    2004-01-01

    The demographic processes that drive the spread of populations through environments and in turn determine the abundance of organisms are the same demographic processes that drive the spread of genes through populations and in turn determine gene frequencies and fitness. Conceptually, marked similarities exist in the dynamic processes underlying population ecology and those underlying evolutionary biology. Central to an understanding of both disciplines is life history and its component demogr...

  18. Evolutionary potential games on lattices

    OpenAIRE

    Szabo, Gyorgy; Borsos, Istvan

    2015-01-01

    Game theory provides a general mathematical background to study the effect of pair interactions and evolutionary rules on the macroscopic behavior of multi-player games where players with a finite number of strategies may represent a wide scale of biological objects, human individuals, or even their associations. In these systems the interactions are characterized by matrices that can be decomposed into elementary matrices (games) and classified into four types. The concept of decomposition h...

  19. Evolutionary robotics – A review

    Indian Academy of Sciences (India)

    Dilip Kumar Pratihar

    2003-12-01

    In evolutionary robotics, a suitable robot control system is developed automatically through evolution due to the interactions between the robot and its environment. It is a complicated task, as the robot and the environment constitute a highly dynamical system. Several methods have been tried by various investigators to solve this problem. This paper provides a survey on some of these important studies carried out in the recent past.

  20. Testing evolutionary convergence on Europa

    International Nuclear Information System (INIS)

    A major objective in solar system exploration is the insertion of appropriate biology-oriented experiments in future missions. We discuss various reasons for suggesting that this type of research be considered a high priority for feasibility studies and, subsequently, for technological development of appropriate melters and submersibles. Based on numerous examples, we argue in favour of the assumption that Darwin's theory is valid for the evolution of life anywhere in the universe. We have suggested how to obtain preliminary insights into the question of the distribution of life in the universe. Universal evolution of intelligent behaviour is at the end of an evolutionary pathway, in which evolution of ion channels in the membrane of microorganisms occurs in its early stages. Further, we have argued that a preliminary test of this conjecture is feasible with experiments on the Europan surface or ocean, involving evolutionary biosignatures (ion channels). This aspect of the exploration for life in the solar system should be viewed as a complement to the astronomical approach for the search of evidence of the later stages of the evolutionary pathways towards intelligent behaviour. (author)

  1. Do Psychological Sex Differences Reflect Evolutionary Bisexual Partitioning?

    Science.gov (United States)

    Trofimova, Irina

    2015-01-01

    This article analyzes sex differences in communicative and exploratory abilities and mental disabilities from the rarely discussed perspective of sex differences in the shape of phenotypic distributions. The article reviews the most consistent findings related to such differences and compares them with the evolutionary theory of sex (ETS). The ETS considers sexual dimorphism as a functional specialization of a species into 2 partitions: variational and conservational. The analysis suggests that male superiority in risk and sensation seeking and physical abilities; higher rates of psychopathy, dyslexia, and autism; and higher birth and accidental death rates reflects the systemic variational function of the male sex. Female superiority in verbal abilities, lawfulness, socialization, empathy, and agreeableness is presented as a reflection of the systemic conservational function of the female sex. From this perspective psychological sex differences in communicative and exploratory abilities might not just be an accidental result of sexual selection or labor distribution in early humans. It might reflect a global functional differentiation tendency within a species to expand its phenotypic diversity and at the same time to conserve beneficial features in the species' behavior. The article also offers an addition to the ETS by suggesting that the male sex (variable partition) plays an evolutionary role in pruning of the redundant excesses in a species' bank of beneficial characteristics despite resistance from the conservational partition. PMID:26721176

  2. Analysis of birth intervals in a non-contracepting Indian population: an evolutionary ecological approach.

    Science.gov (United States)

    Nath, D C; Leonetti, D L; Steele, M S

    2000-07-01

    Reproductive strategies are related to ecological constraints. This paper examines data on early birth spacing in a scheduled caste, Bengali-speaking, non-contracepting population of the Karimganj district of southern Assam, India, taking an evolutionary ecological perspective. It is found that on average birth intervals closed by boy-boy are longer than those closed by girl-girl. Birth spacing tends to be longer among upper-income and Craftsman sub-caste mothers. The presence of a 'grandmother' in the household shortens spacing. These findings are compatible with an evolutionary-based reproductive decision-making process. PMID:10979228

  3. Evolutionary explanations in medical and health profession courses: are you answering your students' "why" questions?

    Directory of Open Access Journals (Sweden)

    Malyango Avelin A

    2005-05-01

    Full Text Available Abstract Background Medical and pre-professional health students ask questions about human health that can be answered in two ways, by giving proximate and evolutionary explanations. Proximate explanations, most common in textbooks and classes, describe the immediate scientifically known biological mechanisms of anatomical characteristics or physiological processes. These explanations are necessary but insufficient. They can be complemented with evolutionary explanations that describe the evolutionary processes and principles that have resulted in human biology we study today. The main goal of the science of Darwinian Medicine is to investigate human disease, disorders, and medical complications from an evolutionary perspective. Discussion This paper contrasts the differences between these two types of explanations by describing principles of natural selection that underlie medical questions. Thus, why is human birth complicated? Why does sickle cell anemia exist? Why do we show symptoms like fever, diarrhea, and coughing when we have infection? Why do we suffer from ubiquitous age-related diseases like arteriosclerosis, Alzheimer's and others? Why are chronic diseases like type II diabetes and obesity so prevalent in modern society? Why hasn't natural selection eliminated the genes that cause common genetic diseases like hemochromatosis, cystic fibrosis, Tay sachs, PKU and others? Summary In giving students evolutionary explanations professors should underscore principles of natural selection, since these can be generalized for the analysis of many medical questions. From a research perspective, natural selection seems central to leading hypotheses of obesity and type II diabetes and might very well explain the occurrence of certain common genetic diseases like cystic fibrosis, hemochromatosis, Tay sachs, Fragile X syndrome, G6PD and others because of their compensating advantages. Furthermore, armed with evolutionary explanations, health care

  4. A paleontological perspective of vertebrate origin

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The Early Cambrian Haikouichthys and Haikouella have been claimed to be related to contribute in an important way to our understanding of vertebrate origin, but there have been heated debates about how exactly they are to be interpreted. New discoveries of numerous specimens of Haikouichthys not only confirm the identity of previously described structures such as the dorsal and the ventral fins, and chevron-shaped myomeres, but also reveal many new important characteristics, including sensory organs of the head (e.g. large eyes), and a prominent notochord with differentiated vertebral elements. This "first fish" appears, however, to retain primitive reproductive features of acraniates, suggesting that it is a stem-group craniates. A new order (Myllokunmingiida) and a new family (Myllokunmingiidae) are erected, and a new species, Zhongjianichthys rostratus (gen. et sp. nov.), is described herein. Over 1400 newly-discovered specimens of Haikouella provide a wealth of anatomical information on this organism. It differs from chordates in many organs and organ systems, including the skin, muscles, respiratory, circulatory and nervous systems. In contrast, its body-design resembles that of vetulicolians, and the presence of a "transitional" nervous system with both dorsal and ventral nerve cords suggests an affinity with living hemichordates. On the basis of these and other recent findings of fossil deuterostomes, a five-step hypothesis for vertebrate origin is proposed, intended to bridge the long- standing gap between protostomes and vertebrates. Four of the five steps accord with established ideas current in modern evolutionary zoology. Evidence for the first step is obtainable only from fossils, and specifically from fossils found from South China, hence the crucial importance of S. China sites for our understanding of early vertebrate origins and evolution. Accordingly, South China is suggested as the oldest-known birthplace of the whole vertebrates.

  5. Nme gene family evolutionary history reveals pre-metazoan origins and high conservation between humans and the sea anemone, Nematostella vectensis.

    Directory of Open Access Journals (Sweden)

    Thomas Desvignes

    Full Text Available BACKGROUND: The Nme gene family is involved in multiple physiological and pathological processes such as cellular differentiation, development, metastatic dissemination, and cilia functions. Despite the known importance of Nme genes and their use as clinical markers of tumor aggressiveness, the associated cellular mechanisms remain poorly understood. Over the last 20 years, several non-vertebrate model species have been used to investigate Nme functions. However, the evolutionary history of the family remains poorly understood outside the vertebrate lineage. The aim of the study was thus to elucidate the evolutionary history of the Nme gene family in Metazoans. METHODOLOGY/PRINCIPAL FINDINGS: Using a total of 21 eukaryote species including 14 metazoans, the evolutionary history of Nme genes was reconstructed in the metazoan lineage. We demonstrated that the complexity of the Nme gene family, initially thought to be restricted to chordates, was also shared by the metazoan ancestor. We also provide evidence suggesting that the complexity of the family is mainly a eukaryotic innovation, with the exception of Nme8 that is likely to be a choanoflagellate/metazoan innovation. Highly conserved gene structure, genomic linkage, and protein domains were identified among metazoans, some features being also conserved in eukaryotes. When considering the entire Nme family, the starlet sea anemone is the studied metazoan species exhibiting the most conserved gene and protein sequence features with humans. In addition, we were able to show that most of the proteins known to interact with human NME proteins were also found in starlet sea anemone. CONCLUSION/SIGNIFICANCE: Together, our observations further support the association of Nme genes with key cellular functions that have been conserved throughout metazoan evolution. Future investigations of evolutionarily conserved Nme gene functions using the starlet sea anemone could shed new light on a wide variety of

  6. The uncertain foundation of neo-Darwinism: metaphysical and epistemological pluralism in the evolutionary synthesis.

    Science.gov (United States)

    Delisle, Richard G

    2009-06-01

    The Evolutionary Synthesis is often seen as a unification process in evolutionary biology, one which provided this research area with a solid common theoretical foundation. As such, neo-Darwinism is believed to constitute from this time onward a single, coherent, and unified movement offering research guidelines for investigations. While this may be true if evolutionary biology is solely understood as centred around evolutionary mechanisms, an entirely different picture emerges once other aspects of the founding neo-Darwinists' views are taken into consideration, aspects potentially relevant to the elaboration of an evolutionary worldview: the tree of life, the ontological distinctions of the main cosmic entities (inert matter, biological organisms, mind), the inherent properties of self-organizing matter, evolutionary ethics, and so on. Profound tensions and inconsistencies are immediately revealed in the neo-Darwinian movement once this broader perspective is adopted. This pluralism is such that it is possible to identify at least three distinct and quasi-incommensurable epistemological/metaphysical frameworks as providing a proper foundation for neo-Darwinism. The analysis of the views of Theodosius Dobzhansky, Bernhard Rensch, and Ernst Mayr will illustrate this untenable pluralism, one which requires us to conceive of the neo-Darwinian research agenda as being conducted in more than one research programme or research tradition at the same time.

  7. Women, behavior, and evolution: understanding the debate between feminist evolutionists and evolutionary psychologists.

    Science.gov (United States)

    Liesen, Laurette T

    2007-03-01

    Often since the early 1990s, feminist evolutionists have criticized evolutionary psychologists, finding fault in their analyses of human male and female reproductive behavior. Feminist evolutionists have criticized various evolutionary psychologists for perpetuating gender stereotypes, using questionable methodology, and exhibiting a chill toward feminism. Though these criticisms have been raised many times, the conflict itself has not been fully analyzed. Therefore, I reconsider this conflict, both in its origins and its implications. I find that the approaches and perspectives of feminist evolutionists and evolutionary psychologists are distinctly different, leading many of the former to work in behavioral ecology, primatology, and evolutionary biology. Invitingly to feminist evolutionists, these three fields emphasize social behavior and the influences of environmental variables; in contrast, evolutionary psychology has come to rely on assumptions deemphasizing the pliability of psychological mechanisms and the flexibility of human behavior. In behavioral ecology, primatology, and evolutionary biology, feminist evolutionists have found old biases easy to correct and new hypotheses practical to test, offering new insights into male and female behavior, explaining the emergence and persistence of patriarchy, and potentially bringing closer a prime feminist goal, sexual equality. PMID:18208338

  8. Proteomic characterization and evolutionary analyses of zona pellucida domain-containing proteins in the egg coat of the cephalochordate, Branchiostoma belcheri

    Directory of Open Access Journals (Sweden)

    Xu Qianghua

    2012-12-01

    Full Text Available Abstract Background Zona pellucida domain-containing proteins (ZP proteins have been identified as the principle constituents of the egg coat (EC of diverse metazoan taxa, including jawed vertebrates, urochordates and molluscs that span hundreds of millions of years of evolutionary divergence. Although ZP proteins generally contain the zona pellucida (ZP structural modules to fulfill sperm recognition and EC polymerization functions during fertilization, the primary sequences of the ZP proteins from the above-mentioned animal classes are drastically different, which makes it difficult to assess the evolutionary relationships of ZP proteins. To understand the origin of vertebrate ZP proteins, we characterized the egg coat components of Branchiostoma belcheri, an invertebrate species that belongs to the chordate subphylum Cephalochordata. Results Five ZP proteins (BbZP1-5 were identified by mass spectrometry analyses using the egg coat extracts from both unfertilized and fertilized eggs. In addition to the C-terminal ZP module in each of the BbZPs, the majority contain a low-density lipoprotein receptor domain and a von Willebrand factor type A (vWFA domain, but none possess an EGF-like domain that is frequently observed in the ZP proteins of urochordates. Fluorescence in situ hybridization and immuno-histochemical analyses of B. belcheri ovaries showed that the five BbZPs are synthesized predominantly in developing eggs and deposited around the extracellular space of the egg, which indicates that they are bona fide egg coat ZP proteins. BbZP1, BbZP3 and BbZP4 are significantly more abundant than BbZP2 and BbZP5 in terms of gene expression levels and the amount of mature proteins present on the egg coats. The major ZP proteins showed high polymorphism because multiple variants are present with different molecular weights. Sequence comparison and phylogenetic analysis between the ZP proteins from cephalochordates, urochordates and vertebrates

  9. Structural and functional insights into the ligand-binding domain of a nonduplicated retinoid X nuclear receptor from the invertebrate chordate amphioxus

    OpenAIRE

    Tocchini-Valentini, Guiseppe D.; Rochel, Natacha; Escriva, Hector; Germain, Pierre; Peluso-Iltis, Carole; Paris, Mathilde; Sanglier-Cianferani, Sarah; Van Dorsselaer, Alain; Moras, Dino; Laudet, Vincent

    2009-01-01

    Retinoid X nuclear receptors (RXRs), as well as their insect orthologue, ultraspiracle protein (USP), play an important role in the transcription regulation mediated by the nuclear receptors as the common partner of many other nuclear receptors. Phylogenetic and structural studies have shown that the several evolutionary shifts have modified the ligand binding ability of RXRs. To understand the vertebrate-specific character of RXRs, we have studied the RXR ligand-binding domain of the cephalo...

  10. Evolutionary Game Theory and Leadership

    Science.gov (United States)

    Guastello, Stephen J.

    2009-01-01

    Comments on the article Leadership, followership, and evolution: Some lessons from the past by Van Vugt, Hogan, and Kaiser. This article offers a fresh perspective on leaders, followers, and their possible origins in nonhuman and primitive human behavior patterns. The connections between group coordination, leadership, and game theory have some…

  11. Evolutionary genomics of animal personality

    NARCIS (Netherlands)

    Van Oers, K.; Mueller, J.C.

    2010-01-01

    Research on animal personality can be approached from both a phenotypic and a genetic perspective. While using a phenotypic approach one can measure present selection on personality traits and their combinations. However, this approach cannot reconstruct the historical trajectory that was taken by e

  12. Evolutionary Governance Theory: An Introduction

    NARCIS (Netherlands)

    Assche, van K.; Beunen, R.; Duineveld, M.

    2014-01-01

    This short books offers the reader a remarkable new perspective on the way markets, laws and societies evolve together. It can be of use to anyone interested in development, market and public sector reform, public administration, politics & law. Based on a wide variety of case studies on three c

  13. Micro Evolutionary Processes and Adaptation

    Institute of Scientific and Technical Information of China (English)

    SHADMANOV R K; RUBAN I N; VOROPAEVA N L; SHADMANOVA A R

    2008-01-01

    @@ It would be well to note that in the absence of clear data about the formation of adaptation systems,or mechanisms of their occurrence,all that is recognized is the realization of the micro evolutionary processes.There is no well-defined connection between information exchange and formation of adaptation systems.Obviously,it occurs because mechanisms and systems reacting to any external actions are not considered from the point of view of "coexistence" of dynamic and static processes and structures.

  14. Steps Towards an Evolutionary Physics

    CERN Document Server

    Tiezzi, E

    2006-01-01

    If thermodynamics is to physics as logic is to philosophy, recent theoretical advancements lend new coherence to the marvel and dynamism of life on Earth. Enzo Tiezzi's "Steps Towards an Evolutionary Physics" is a primer and guide, to those who would to stand on the shoulders of giants to attain this view: Heisenberg, Planck, Bateson, Varela, and Prigogine as well as notable contemporary scientists. The adventure of such a free and enquiring spirit thrives not so much on answers as on new questions. The book offers a new gestalt on the uncertainty principle and concept of probability. A wide r

  15. Metabolism at Evolutionary Optimal States

    Directory of Open Access Journals (Sweden)

    Iraes Rabbers

    2015-06-01

    Full Text Available Metabolism is generally required for cellular maintenance and for the generation of offspring under conditions that support growth. The rates, yields (efficiencies, adaptation time and robustness of metabolism are therefore key determinants of cellular fitness. For biotechnological applications and our understanding of the evolution of metabolism, it is necessary to figure out how the functional system properties of metabolism can be optimized, via adjustments of the kinetics and expression of enzymes, and by rewiring metabolism. The trade-offs that can occur during such optimizations then indicate fundamental limits to evolutionary innovations and bioengineering. In this paper, we review several theoretical and experimental findings about mechanisms for metabolic optimization.

  16. Improving DNA Computing Using Evolutionary Techniques

    Directory of Open Access Journals (Sweden)

    Godar J. Ibrahim

    2016-03-01

    Full Text Available the field of DNA Computing has attracted many biologists and computer scientists as it has a biological interface, small size and substantial parallelism. DNA computing depends on DNA molecules’ biochemical reactions which they can randomly anneal and they might accidentally cause improper or unattractive computations. This will inspire opportunities to use evolutionary computation via DNA. Evolutionary Computation emphasizes on probabilistic search and optimization methods which are mimicking the organic evolution models. The research work aims at offering a simulated evolutionary DNA computing model which incorporates DNA computing with an evolutionary algorithm. This evolutionary approach provides the likelihood for increasing dimensionality through replacing the typical filtering method by an evolutionary one. Thus, via iteratively increasing and recombination a population of strands, eliminating incorrect solutions from the population, and choosing the best solutions via gel electrophoresis, an optimal or near-optimal solution can be evolved rather than extracted from the initial population.

  17. The Evolutionary Puzzle of Suicide

    Directory of Open Access Journals (Sweden)

    Henri-Jean Aubin

    2013-12-01

    Full Text Available Mechanisms of self-destruction are difficult to reconcile with evolution’s first rule of thumb: survive and reproduce. However, evolutionary success ultimately depends on inclusive fitness. The altruistic suicide hypothesis posits that the presence of low reproductive potential and burdensomeness toward kin can increase the inclusive fitness payoff of self-removal. The bargaining hypothesis assumes that suicide attempts could function as an honest signal of need. The payoff may be positive if the suicidal person has a low reproductive potential. The parasite manipulation hypothesis is founded on the rodent—Toxoplasma gondii host-parasite model, in which the parasite induces a “suicidal” feline attraction that allows the parasite to complete its life cycle. Interestingly, latent infection by T. gondii has been shown to cause behavioral alterations in humans, including increased suicide attempts. Finally, we discuss how suicide risk factors can be understood as nonadaptive byproducts of evolved mechanisms that malfunction. Although most of the mechanisms proposed in this article are largely speculative, the hypotheses that we raise accept self-destructive behavior within the framework of evolutionary theory.

  18. Behavior Trees for Evolutionary Robotics.

    Science.gov (United States)

    Scheper, Kirk Y W; Tijmons, Sjoerd; de Visser, Cornelis C; de Croon, Guido C H E

    2016-01-01

    Evolutionary Robotics allows robots with limited sensors and processing to tackle complex tasks by means of sensory-motor coordination. In this article we show the first application of the Behavior Tree framework on a real robotic platform using the evolutionary robotics methodology. This framework is used to improve the intelligibility of the emergent robotic behavior over that of the traditional neural network formulation. As a result, the behavior is easier to comprehend and manually adapt when crossing the reality gap from simulation to reality. This functionality is shown by performing real-world flight tests with the 20-g DelFly Explorer flapping wing micro air vehicle equipped with a 4-g onboard stereo vision system. The experiments show that the DelFly can fully autonomously search for and fly through a window with only its onboard sensors and processing. The success rate of the optimized behavior in simulation is 88%, and the corresponding real-world performance is 54% after user adaptation. Although this leaves room for improvement, it is higher than the 46% success rate from a tuned user-defined controller. PMID:26606468

  19. Evolutionary potential games on lattices

    Science.gov (United States)

    Szabó, György; Borsos, István

    2016-04-01

    Game theory provides a general mathematical background to study the effect of pair interactions and evolutionary rules on the macroscopic behavior of multi-player games where players with a finite number of strategies may represent a wide scale of biological objects, human individuals, or even their associations. In these systems the interactions are characterized by matrices that can be decomposed into elementary matrices (games) and classified into four types. The concept of decomposition helps the identification of potential games and also the evaluation of the potential that plays a crucial role in the determination of the preferred Nash equilibrium, and defines the Boltzmann distribution towards which these systems evolve for suitable types of dynamical rules. This survey draws parallel between the potential games and the kinetic Ising type models which are investigated for a wide scale of connectivity structures. We discuss briefly the applicability of the tools and concepts of statistical physics and thermodynamics. Additionally the general features of ordering phenomena, phase transitions and slow relaxations are outlined and applied to evolutionary games. The discussion extends to games with three or more strategies. Finally we discuss what happens when the system is weakly driven out of the "equilibrium state" by adding non-potential components representing games of cyclic dominance.

  20. Evolutionary epistemology a multiparadigm program

    CERN Document Server

    Pinxten, Rik

    1987-01-01

    This volume has its already distant origin in an inter­national conference on Evolutionary Epistemology the editors organized at the University of Ghent in November 1984. This conference aimed to follow up the endeavor started at the ERISS (Epistemologically Relevant Internalist Sociology of Science) conference organized by Don Campbell and Alex Rosen­ berg at Cazenovia Lake, New York, in June 1981, whilst in­ jecting the gist of certain current continental intellectual developments into a debate whose focus, we thought, was in danger of being narrowed too much, considering the still underdeveloped state of affairs in the field. Broadly speaking, evolutionary epistemology today con­ sists of two interrelated, yet qualitatively distinct inves­ tigative efforts. Both are drawing on Darwinian concepts, which may explain why many people have failed to discriminate them. One is the study of the evolution of the cognitive apparatus of living organisms, which is first and foremost the province of biologists and...

  1. Evolutionary expansion of the Monogenea.

    Science.gov (United States)

    Kearn, G C

    1994-12-01

    The evolutionary expansion of the monogeneans has taken place in parallel with the diversification of the fish-like vertebrates. In this article the main trends in monogenean evolution are traced from a hypothetical skin-parasitic ancestor on early vertebrates. Special consideration is given to the following topics: early divergence between skin feeders and blood feeders; diversification and specialization of the haptor for attachment to skin; transfer from host to host, viviparity and the success of the gyrodactylids; predation on skin parasites and camouflage; colonization of the buccal and branchial cavities; diversification and specialization of the haptor for attachment to the gills; phoresy in gill parasites; the development of endoparasitism and the origin of the cestodes; the success of dactylogyroidean gill parasites; the uniqueness of the polyopisthocotyleans; ovoviviparity and the colonization of the tetrapods. Host specificity has been the guiding force of coevolution between monogeneans and their vertebrate hosts, but the establishment of monogeneans on unrelated hosts sharing the same environment (host-switching) may have been underestimated. Host-switching has provided significant opportunities for evolutionary change of direction and is probably responsible for the establishment of monogeneans on cephalopod molluscs, on the hippopotamus and possibly on chelonians. There are indications that host-switching may be more common in monogeneans that spread by direct transfer of adults/juveniles from host to host. A limitation on the further expansion of monogeneans is the need for water for the dispersal of the infective larva (oncomiracidium).

  2. Evolutionary development of tensegrity structures.

    Science.gov (United States)

    Lobo, Daniel; Vico, Francisco J

    2010-09-01

    Contributions from the emerging fields of molecular genetics and evo-devo (evolutionary developmental biology) are greatly benefiting the field of evolutionary computation, initiating a promise of renewal in the traditional methodology. While direct encoding has constituted a dominant paradigm, indirect ways to encode the solutions have been reported, yet little attention has been paid to the benefits of the proposed methods to real problems. In this work, we study the biological properties that emerge by means of using indirect encodings in the context of form-finding problems. A novel indirect encoding model for artificial development has been defined and applied to an engineering structural-design problem, specifically to the discovery of tensegrity structures. This model has been compared with a direct encoding scheme. While the direct encoding performs similarly well to the proposed method, indirect-based results typically outperform the direct-based results in aspects not directly linked to the nature of the problem itself, but to the emergence of properties found in biological organisms, like organicity, generalization capacity, or modularity aspects which are highly valuable in engineering. PMID:20619314

  3. Behavior Trees for Evolutionary Robotics.

    Science.gov (United States)

    Scheper, Kirk Y W; Tijmons, Sjoerd; de Visser, Cornelis C; de Croon, Guido C H E

    2016-01-01

    Evolutionary Robotics allows robots with limited sensors and processing to tackle complex tasks by means of sensory-motor coordination. In this article we show the first application of the Behavior Tree framework on a real robotic platform using the evolutionary robotics methodology. This framework is used to improve the intelligibility of the emergent robotic behavior over that of the traditional neural network formulation. As a result, the behavior is easier to comprehend and manually adapt when crossing the reality gap from simulation to reality. This functionality is shown by performing real-world flight tests with the 20-g DelFly Explorer flapping wing micro air vehicle equipped with a 4-g onboard stereo vision system. The experiments show that the DelFly can fully autonomously search for and fly through a window with only its onboard sensors and processing. The success rate of the optimized behavior in simulation is 88%, and the corresponding real-world performance is 54% after user adaptation. Although this leaves room for improvement, it is higher than the 46% success rate from a tuned user-defined controller.

  4. EVOLUTIONARY THEORY AND THE MARKET COMPETITION

    OpenAIRE

    Nicoleta SIRGHI

    2014-01-01

    Evolutionary theory study of processes that transform economy for firms, institutions, industries, employment, production, trade and growth within, through the actions of diverse agents from experience and interactions, using evolutionary methodology. Evolutionary theory analyses the unleashing of a process of technological and institutional innovation by generating and testing a diversity of ideas which discover and accumulate more survival value for the costs incurred than competing alterna...

  5. Evolutionary robotics: what, why, and where to

    OpenAIRE

    Doncieux, Stephane; Bredeche, Nicolas; Mouret, Jean-Baptiste; Eiben, Agoston E. (Gusz)

    2015-01-01

    Evolutionary robotics applies the selection, variation, and heredity principles of natural evolution to the design of robots with embodied intelligence. It can be considered as a subfield of robotics that aims to create more robust and adaptive robots. A pivotal feature of the evolutionary approach is that it considers the whole robot at once, and enables the exploitation of robot features in a holistic manner. Evolutionary robotics can also be seen as an innovative approach to the study of e...

  6. The Citation Field of Evolutionary Economics

    OpenAIRE

    Dolfsma, Wilfred; Leydesdorff, Loet

    2010-01-01

    Evolutionary economics has developed into an academic field of its own, institutionalized around, amongst others, the Journal of Evolutionary Economics (JEE). This paper analyzes the way and extent to which evolutionary economics has become an interdisciplinary journal, as its aim was: a journal that is indispensable in the exchange of expert knowledge on topics and using approaches that relate naturally with it. Analyzing citation data for the relevant academic field for the Journal of Evolu...

  7. An introduction to evolutionary developmental psychology.

    Science.gov (United States)

    Machluf, Karin; Liddle, James R; Bjorklund, David F

    2014-04-29

    Evolutionary developmental psychology represents a synthesis of modern evolutionary theory and developmental psychology. Here we introduce the special issue on evolutionary developmental psychology by briefly discussing the history of this field and then summarizing the variety of topics that are covered. In this special issue, leading researchers provide a collection of theoretical and empirical articles that highlight recent findings and propose promising areas for future research.

  8. Evolutionary Autonomous Health Monitoring System (EAHMS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — For supporting NASA's Robotics, Tele-Robotics and Autonomous Systems Roadmap, we are proposing the "Evolutionary Autonomous Health Monitoring System" (EAHMS) for...

  9. Evolutionary ecology in silico: Does mathematical modelling help in understanding `generic' trends?

    Indian Academy of Sciences (India)

    Debashish Chowdhury; Dietrich Stauffer

    2005-03-01

    Motivated by the results of recent laboratory experiments, as well as many earlier field observations, that evolutionary changes can take place in ecosystems over relatively short ecological time scales, several ‘unified’ mathematical models of evolutionary ecology have been developed over the last few years with the aim of describing the statistical properties of data related to the evolution of ecosystems. Moreover, because of the availability of sufficiently fast computers, it has become possible to carry out detailed computer simulations of these models. For the sake of completeness and to put these recent developments in perspective, we begin with a brief summary of some older models of ecological phenomena and evolutionary processes. However, the main aim of this article is to review critically these ‘unified’ models, particularly those published in the physics literature, in simple language that makes the new theories accessible to a wider audience.

  10. Evolutionary triangulation: informing genetic association studies with evolutionary evidence.

    Science.gov (United States)

    Huang, Minjun; Graham, Britney E; Zhang, Ge; Harder, Reed; Kodaman, Nuri; Moore, Jason H; Muglia, Louis; Williams, Scott M

    2016-01-01

    Genetic studies of human diseases have identified many variants associated with pathogenesis and severity. However, most studies have used only statistical association to assess putative relationships to disease, and ignored other factors for evaluation. For example, evolution is a factor that has shaped disease risk, changing allele frequencies as human populations migrated into and inhabited new environments. Since many common variants differ among populations in frequency, as does disease prevalence, we hypothesized that patterns of disease and population structure, taken together, will inform association studies. Thus, the population distributions of allelic risk variants should reflect the distributions of their associated diseases. Evolutionary Triangulation (ET) exploits this evolutionary differentiation by comparing population structure among three populations with variable patterns of disease prevalence. By selecting populations based on patterns where two have similar rates of disease that differ substantially from a third, we performed a proof of principle analysis for this method. We examined three disease phenotypes, lactase persistence, melanoma, and Type 2 diabetes mellitus. We show that for lactase persistence, a phenotype with a simple genetic architecture, ET identifies the key gene, lactase. For melanoma, ET identifies several genes associated with this disease and/or phenotypes related to it, such as skin color genes. ET was less obviously successful for Type 2 diabetes mellitus, perhaps because of the small effect sizes in known risk loci and recent environmental changes that have altered disease risk. Alternatively, ET may have revealed new genes involved in conferring disease risk for diabetes that did not meet nominal GWAS significance thresholds. We also compared ET to another method used to filter for phenotype associated genes, population branch statistic (PBS), and show that ET performs better in identifying genes known to associate with

  11. On the Development of Human Representational Competence from an Evolutionary Point of View: From Episodic to Virtual Culture.

    Science.gov (United States)

    Kaput, James J.

    Via computational media, humans are entering a fifth stage of cognitive development leading to a virtual culture. This culture is seen as replacing the writing-based theoretic culture. Background information about the first four stages of mental evolution or cognitive development is provided. It is suggested that the evolutionary perspective needs…

  12. Evolutionary genomics of animal personality

    OpenAIRE

    Oers, Kees van; Mueller, Jakob C

    2010-01-01

    Research on animal personality can be approached from both a phenotypic and a genetic perspective. While using a phenotypic approach one can measure present selection on personality traits and their combinations. However, this approach cannot reconstruct the historical trajectory that was taken by evolution. Therefore, it is essential for our understanding of the causes and consequences of personality diversity to link phenotypic variation in personality traits with polymorphisms in genomic r...

  13. Evolutionary concepts in ecotoxicology: tracing the genetic background of differential cadmium sensitivities in invertebrate lineages.

    Science.gov (United States)

    Dallinger, Reinhard; Höckner, Martina

    2013-07-01

    In many toxicological and ecotoxicological studies and experimental setups, the investigator is mainly interested in traditional parameters such as toxicity data and effects of toxicants on molecular, cellular or physiological functions of individuals, species or statistical populations. It is clear, however, that such approaches focus on the phenotype level of animal species, whilst the genetic and evolutionary background of reactions to environmental toxicants may remain untold. In ecotoxicological risk assessment, moreover, species sensitivities towards pollutants are often regarded as random variables in a statistical approach. Beyond statistics, however, toxicant sensitivity of every species assumes a biological significance, especially if we consider that sensitivity traits have developed in lineages of species with common evolutionary roots. In this article, the genetic and evolutionary background of differential Cd sensitivities among invertebrate populations and species and their potential of adaptation to environmental Cd exposure will be highlighted. Important evolutionary and population genetic concepts such as genome structure and their importance for evolutionary adaptation, population structure of affected individuals, as well as micro and macroevolutionary mechanisms of Cd resistance in invertebrate lineages will be stressed by discussing examples of work from our own laboratory along with a review of relevant literature data and a brief discussion of open questions along with some perspectives for further research. Both, differences and similarities in Cd sensitivity traits of related invertebrate species can only be understood if we consider the underlying evolutionary processes and genetic (or epigenetic) mechanisms. Keeping in mind this perception can help us to better understand and interpret more precisely why the sensitivity of some species or species groups towards a certain toxicant (or metal) may be ranked in the lower or higher range of

  14. TNFRSF13B Genetic variability an anthropological - evolutionary approach to Biomedical Research

    OpenAIRE

    Sazzini, Marco

    2009-01-01

    In the recent years TNFRSF13B coding variants have been implicated by clinical genetics studies in Common Variable Immunodeficiency (CVID), the most common clinically relevant primary immunodeficiency in individuals of European ancestry, but their functional effects in relation to the development of the disease have not been entirely established. To examine the potential contribution of such variants to CVID, the more comprehensive perspective of an evolutionary approach was applied in this s...

  15. The Evolutionary Ecology of Human Lactation: Correlates of Duration of Breastfeeding

    OpenAIRE

    McKerracher, Luseadra

    2016-01-01

    Humans breastfeed our infants for less time than expected for primates of our size. Additionally, human breastfeeding duration appears more variable than in nonhuman species. This early and flexible weaning pattern affects maternal fertility as well as infant health and survivorship, from both within- and across- species perspectives. So, understanding what factors enabled humans to wean relatively early and flexibly is an important goal for human evolutionary demography. Yet, what these fact...

  16. Evolutionary modelling of the macro-economic impacts of catastrophic flood events

    OpenAIRE

    Safarzynska, Karolina; Brouwer, Roy; Hofkes, Marjan

    2013-01-01

    This paper examines the possible contribution of evolutionary economics to macro-economic modelling of flood impacts to provide guidance for future economic risk modelling. Most macro-economic models start from a neoclassical economic perspective and focus on equilibrium outcomes, either in a static or dynamic way, and describe economic processes at a high level of aggregation. As a consequence, they typically fail to account for the complexity of social interactions and other behavioural res...

  17. The Limits of Culture? Society, Evolutionary Psychology and the History of Violence

    OpenAIRE

    Wood, J. Carter

    2007-01-01

    Recent debates about the meaning and role of cultural history have focused on the relationship between 'culture' and 'society'. Some have taken this opportunity to position cultural history as a site of resistance to 'biological' explanations of human behaviour. In contrast, this article argues that 'biological' methodologies - particularly the perspectives of evolutionary psychology - can usefully contribute to the historical understanding of culture and social development. To this end, it o...

  18. Markov Networks in Evolutionary Computation

    CERN Document Server

    Shakya, Siddhartha

    2012-01-01

    Markov networks and other probabilistic graphical modes have recently received an upsurge in attention from Evolutionary computation community, particularly in the area of Estimation of distribution algorithms (EDAs).  EDAs have arisen as one of the most successful experiences in the application of machine learning methods in optimization, mainly due to their efficiency to solve complex real-world optimization problems and their suitability for theoretical analysis. This book focuses on the different steps involved in the conception, implementation and application of EDAs that use Markov networks, and undirected models in general. It can serve as a general introduction to EDAs but covers also an important current void in the study of these algorithms by explaining the specificities and benefits of modeling optimization problems by means of undirected probabilistic models. All major developments to date in the progressive introduction of Markov networks based EDAs are reviewed in the book. Hot current researc...

  19. Evolutionary advantages of adaptive rewarding

    CERN Document Server

    Szolnoki, Attila

    2012-01-01

    Our wellbeing depends as much on our personal success, as it does on the success of our society. The realization of this fact makes cooperation a very much needed trait. Experiments have shown that rewards can elevate our readiness to cooperate, but since giving a reward inevitably entails paying a cost for it, the emergence and stability of such behavior remain elusive. Here we show that allowing for the act of rewarding to self-organize in dependence on the success of cooperation creates several evolutionary advantages that instill new ways through which collaborative efforts are promoted. Ranging from indirect territorial battle to the spontaneous emergence and destruction of coexistence, phase diagrams and the underlying spatial patterns reveal fascinatingly reach social dynamics that explains why this costly behavior has evolved and persevered. Comparisons with adaptive punishment, however, uncover an Achilles heel of adaptive rewarding that is due to over-aggression, which in turn hinders optimal utiliz...

  20. Evolutionary Industrial Physical Model Generation

    Science.gov (United States)

    Carrascal, Alberto; Alberdi, Amaia

    Both complexity and lack of knowledge associated to physical processes makes physical models design an arduous task. Frequently, the only available information about the physical processes are the heuristic data obtained from experiments or at best a rough idea on what are the physical principles and laws that underlie considered physical processes. Then the problem is converted to find a mathematical expression which fits data. There exist traditional approaches to tackle the inductive model search process from data, such as regression, interpolation, finite element method, etc. Nevertheless, these methods either are only able to solve a reduced number of simple model typologies, or the given black-box solution does not contribute to clarify the analyzed physical process. In this paper a hybrid evolutionary approach to search complex physical models is proposed. Tests carried out on a real-world industrial physical process (abrasive water jet machining) demonstrate the validity of this approach.

  1. Evolutionary history of exon shuffling.

    Science.gov (United States)

    França, Gustavo S; Cancherini, Douglas V; de Souza, Sandro J

    2012-06-01

    Exon shuffling has been characterized as one of the major evolutionary forces shaping both the genome and the proteome of eukaryotes. This mechanism was particularly important in the creation of multidomain proteins during animal evolution, bringing a number of functional genetic novelties. Here, genome information from a variety of eukaryotic species was used to address several issues related to the evolutionary history of exon shuffling. By comparing all protein sequences within each species, we were able to characterize exon shuffling signatures throughout metazoans. Intron phase (the position of the intron regarding the codon) and exon symmetry (the pattern of flanking introns for a given exon or block of adjacent exons) were features used to evaluate exon shuffling. We confirmed previous observations that exon shuffling mediated by phase 1 introns (1-1 exon shuffling) is the predominant kind in multicellular animals. Evidence is provided that such pattern was achieved since the early steps of animal evolution, supported by a detectable presence of 1-1 shuffling units in Trichoplax adhaerens and a considerable prevalence of them in Nematostella vectensis. In contrast, Monosiga brevicollis, one of the closest relatives of metazoans, and Arabidopsis thaliana, showed no evidence of 1-1 exon or domain shuffling above what it would be expected by chance. Instead, exon shuffling events are less abundant and predominantly mediated by phase 0 introns (0-0 exon shuffling) in those non-metazoan species. Moreover, an intermediate pattern of 1-1 and 0-0 exon shuffling was observed for the placozoan T. adhaerens, a primitive animal. Finally, characterization of flanking intron phases around domain borders allowed us to identify a common set of symmetric 1-1 domains that have been shuffled throughout the metazoan lineage.

  2. Evolutionary primacy of sodium bioenergetics

    Directory of Open Access Journals (Sweden)

    Wolf Yuri I

    2008-04-01

    Full Text Available Abstract Background The F- and V-type ATPases are rotary molecular machines that couple translocation of protons or sodium ions across the membrane to the synthesis or hydrolysis of ATP. Both the F-type (found in most bacteria and eukaryotic mitochondria and chloroplasts and V-type (found in archaea, some bacteria, and eukaryotic vacuoles ATPases can translocate either protons or sodium ions. The prevalent proton-dependent ATPases are generally viewed as the primary form of the enzyme whereas the sodium-translocating ATPases of some prokaryotes are usually construed as an exotic adaptation to survival in extreme environments. Results We combine structural and phylogenetic analyses to clarify the evolutionary relation between the proton- and sodium-translocating ATPases. A comparison of the structures of the membrane-embedded oligomeric proteolipid rings of sodium-dependent F- and V-ATPases reveals nearly identical sets of amino acids involved in sodium binding. We show that the sodium-dependent ATPases are scattered among proton-dependent ATPases in both the F- and the V-branches of the phylogenetic tree. Conclusion Barring convergent emergence of the same set of ligands in several lineages, these findings indicate that the use of sodium gradient for ATP synthesis is the ancestral modality of membrane bioenergetics. Thus, a primitive, sodium-impermeable but proton-permeable cell membrane that harboured a set of sodium-transporting enzymes appears to have been the evolutionary predecessor of the more structurally demanding proton-tight membranes. The use of proton as the coupling ion appears to be a later innovation that emerged on several independent occasions. Reviewers This article was reviewed by J. Peter Gogarten, Martijn A. Huynen, and Igor B. Zhulin. For the full reviews, please go to the Reviewers' comments section.

  3. Evolutionary design assistants for architecture

    Directory of Open Access Journals (Sweden)

    N. Onur Sönmez

    2015-04-01

    Full Text Available In its parallel pursuit of an increased competitivity for design offices and more pleasurable and easier workflows for designers, artificial design intelligence is a technical, intellectual, and political challenge. While human-machine cooperation has become commonplace through Computer Aided Design (CAD tools, a more improved collaboration and better support appear possible only through an endeavor into a kind of artificial design intelligence, which is more sensitive to the human perception of affairs.Considered as part of the broader Computational Design studies, the research program of this quest can be called Artificial / Autonomous / Automated Design (AD. The current available level of Artificial Intelligence (AI for design is limited and a viable aim for current AD would be to develop design assistants that are capable of producing drafts for various design tasks. Thus, the overall aim of this thesis is the development of approaches, techniques, and tools towards artificial design assistants that offer a capability for generating drafts for sub-tasks within design processes. The main technology explored for this aim is Evolutionary Computation (EC, and the target design domain is architecture. The two connected research questions of the study concern, first, the investigation of the ways to develop an architectural design assistant, and secondly, the utilization of EC for the development of such assistants.While developing approaches, techniques, and computational tools for such an assistant, the study also carries out a broad theoretical investigation into the main problems, challenges, and requirements towards such assistants on a rather overall level. Therefore, the research is shaped as a parallel investigation of three main threads interwoven along several levels, moving from a more general level to specific applications. The three research threads comprise, first, theoretical discussions and speculations with regard to both existing

  4. A Hybrid Chaotic Quantum Evolutionary Algorithm

    DEFF Research Database (Denmark)

    Cai, Y.; Zhang, M.; Cai, H.

    2010-01-01

    and enhance the global search ability. A large number of tests show that the proposed algorithm has higher convergence speed and better optimizing ability than quantum evolutionary algorithm, real-coded quantum evolutionary algorithm and hybrid quantum genetic algorithm. Tests also show that when chaos...

  5. Oversimplifying Evolutionary Psychology Leads to Explanatory Gaps

    Science.gov (United States)

    Tate, Chuck; Ledbetter, Jay N.

    2010-01-01

    Comments on Evolutionary psychology: Controversies, questions, prospects, and limitations by Confer et al. They argued that SST cannot explain the existence of either homosexuality or suicide within the human species. We contend that a sufficiently nuanced evolutionary position has no difficulties explaining either phenomenon. Also in this…

  6. On Economic Applications of Evolutionary Game Theory

    OpenAIRE

    Daniel Friedman

    2010-01-01

    Evolutionary games have considerable unrealized potential for modeling substantive economic issues. They promise richer predictions than orthodox game models but often require more extensive specifications. This paper exposits the specification of evolutionary game models and classifies the possible asymptotic behavior for one and two dimensional models.

  7. Handbook of differential equations evolutionary equations

    CERN Document Server

    Dafermos, CM

    2008-01-01

    The material collected in this volume discusses the present as well as expected future directions of development of the field with particular emphasis on applications. The seven survey articles present different topics in Evolutionary PDE's, written by leading experts.- Review of new results in the area- Continuation of previous volumes in the handbook series covering Evolutionary PDEs- Written by leading experts

  8. Information Geometry and Evolutionary Game Theory

    CERN Document Server

    Harper, Marc

    2009-01-01

    The Shahshahani geometry of evolutionary game theory is realized as the information geometry of the simplex, deriving from the Fisher information metric of the manifold of categorical probability distributions. Some essential concepts in evolutionary game theory are realized information-theoretically. Results are extended to the Lotka-Volterra equation and to multiple population systems.

  9. On the Evolutionary Stability of Bargaining Inefficiency

    DEFF Research Database (Denmark)

    Poulsen, Anders

    This paper investigates whether 'tough' bargaining behavior, which gives rise to inefficiency, can be evolutionary stable. We show that in a two-stage Nash Demand Game tough behavior survives. Indeed, almost all the surplus may be wasted. We also study the Ultimatum Game. Here evolutionary...

  10. International Perspectives.

    Science.gov (United States)

    Allen, Kenn; Habermann, Ulla; Chowdhury, Omar Faruque; Guerra, Iraida Manzanilla

    1998-01-01

    Includes "Introduction to International Perspectives" (Allen); "Volunteerism in the Welfare State: The Case of Denmark" (Habermann); "Grassroots Organizing in Bangladesh" (Chowdhury); and "Volunteerism in Latin America" (Guerra). (SK)

  11. The Citation Field of Evolutionary Economics

    CERN Document Server

    Dolfsma, Wilfred

    2010-01-01

    Evolutionary economics has developed into an academic field of its own, institutionalized around, amongst others, the Journal of Evolutionary Economics (JEE). This paper analyzes the way and extent to which evolutionary economics has become an interdisciplinary journal, as its aim was: a journal that is indispensable in the exchange of expert knowledge on topics and using approaches that relate naturally with it. Analyzing citation data for the relevant academic field for the Journal of Evolutionary Economics, we use insights from scientometrics and social network analysis to find that, indeed, the JEE is a central player in this interdisciplinary field aiming mostly at understanding technological and regional dynamics. It does not, however, link firmly with the natural sciences (including biology) nor to management sciences, entrepreneurship, and organization studies. Another journal that could be perceived to have evolutionary acumen, the Journal of Economic Issues, does relate to heterodox economics journa...

  12. Evolutionary Psychiatry and Nosology: Prospects and Limitations

    Directory of Open Access Journals (Sweden)

    Luc Faucher

    2012-11-01

    Full Text Available In this paper, I explain why evolutionary psychiatry is not where the next revolution in psychiatry will come from. I will proceed as follows. Firstly, I will review some of the problems commonly attributed to current nosologies, more specifically to the DSM. One of these problems is the lack of a clear and consensual definition of mental disorder; I will then examine specific attempts to spell out such a definition that use the evolutionary framework. One definition that deserves particular attention (for a number of reasons that I will mention later, is one put forward by Jerome Wakefield. Despite my sympathy for his position, I must indicate a few reasons why I think his attempt might not be able to resolve the problems related to current nosologies. I suggest that it might be wiser for an evolutionary psychiatrist to adopt the more integrative framework of “treatable conditions” (Cosmides and Tooby, 1999. As it is thought that an evolutionary approach can contribute to transforming the way we look at mental disorders, I will provide the reader with a brief sketch of the basic tenets of evolutionary psychology. The picture of the architecture of the human mind that emerges from evolutionary psychology is thought by some to be the crucial backdrop to identifying specific mental disorders and distinguishing them from normal conditions. I will also provide two examples of how evolutionary thinking is supposed to change our thinking about some disorders. Using the case of depression, I will then show what kind of problems evolutionary explanations of particular psychopathologies encounter. In conclusion, I will evaluate where evolutionary thinking leaves us in regard to what I identify as the main problems of our current nosologies. I’ll then argue that the prospects of evolutionary psychiatry are not good.

  13. Smartdata privacy meets evolutionary robotics

    CERN Document Server

    Harvey, Inman; Tomko, George

    2013-01-01

    Privacy by Design and the Promise of SmartData.- SmartData: the Need, the Goal and the Challenge.- Perspectives on Artificial Intelligence.- Context dependent information processing entails scale-free dynamics.- Philosophy and SmartData.- Relevance Realization and the Neurodynamics and Neural Connectivity of General Intelligence.- What Matters: Real Bodies and Virtual Worlds.- The development of autonomous virtual agents.- Patterns of Attractors in the "Brain"".- A Privacy-Enabled Mobile Computing Model Using Intelligent Cloud-Based Services.- Unconstraint the Population: the Benefits of Horiz

  14. Dutton, Davies, and Imaginative Virtual Worlds: The Current State of Evolutionary Aesthetics

    Directory of Open Access Journals (Sweden)

    Joseph Carroll

    2013-12-01

    Full Text Available This paper is a commentary comparing the evolutionary perspectives of Denis Dutton’s The Art Instinct (2009 and Stephen Davies’s The Artful Species (2012. Their topics thus necessarily overlap, but their books have different purposes and a different feel. Davies’s book is an academic exercise. He has no real arguments or claims of his own. Dutton wishes to demonstrate that evolutionary psychology can provide a satisfying naturalistic explanation of aesthetic experience. Neither Davies nor Dutton fully succeeds in his ambition. Davies extends his scepticism well beyond a sensible account of the state of current knowledge about human evolution, and Dutton fails to recognize underlying theoretical differences in his main sources of theoretical inspiration. The limitations in these two works do not define the boundaries of current knowledge in evolutionary aesthetics. The most advanced and adequate concept in the evolutionary humanities is the idea that humans evolved the capacity to create imaginative virtual worlds and use those worlds to guide human behaviour. Both books being considered in this essay approach the idea of imaginative virtual worlds and almost grasp it. Before taking up that topic, the paper shall discuss two subsidiary issues: Dutton’s effort to incorporate sexual selection, and Davies’s sceptical negations about all evolutionary knowledge.

  15. Inflated impact factors? The true impact of evolutionary papers in non-evolutionary journals.

    Science.gov (United States)

    Postma, Erik

    2007-01-01

    Amongst the numerous problems associated with the use of impact factors as a measure of quality are the systematic differences in impact factors that exist among scientific fields. While in theory this can be circumvented by limiting comparisons to journals within the same field, for a diverse and multidisciplinary field like evolutionary biology, in which the majority of papers are published in journals that publish both evolutionary and non-evolutionary papers, this is impossible. However, a journal's overall impact factor may well be a poor predictor for the impact of its evolutionary papers. The extremely high impact factors of some multidisciplinary journals, for example, are by many believed to be driven mostly by publications from other fields. Despite plenty of speculation, however, we know as yet very little about the true impact of evolutionary papers in journals not specifically classified as evolutionary. Here I present, for a wide range of journals, an analysis of the number of evolutionary papers they publish and their average impact. I show that there are large differences in impact among evolutionary and non-evolutionary papers within journals; while the impact of evolutionary papers published in multidisciplinary journals is substantially overestimated by their overall impact factor, the impact of evolutionary papers in many of the more specialized, non-evolutionary journals is significantly underestimated. This suggests that, for evolutionary biologists, publishing in high-impact multidisciplinary journals should not receive as much weight as it does now, while evolutionary papers in more narrowly defined journals are currently undervalued. Importantly, however, their ranking remains largely unaffected. While journal impact factors may thus indeed provide a meaningful qualitative measure of impact, a fair quantitative comparison requires a more sophisticated journal classification system, together with multiple field-specific impact statistics per

  16. Inflated impact factors? The true impact of evolutionary papers in non-evolutionary journals.

    Directory of Open Access Journals (Sweden)

    Erik Postma

    Full Text Available Amongst the numerous problems associated with the use of impact factors as a measure of quality are the systematic differences in impact factors that exist among scientific fields. While in theory this can be circumvented by limiting comparisons to journals within the same field, for a diverse and multidisciplinary field like evolutionary biology, in which the majority of papers are published in journals that publish both evolutionary and non-evolutionary papers, this is impossible. However, a journal's overall impact factor may well be a poor predictor for the impact of its evolutionary papers. The extremely high impact factors of some multidisciplinary journals, for example, are by many believed to be driven mostly by publications from other fields. Despite plenty of speculation, however, we know as yet very little about the true impact of evolutionary papers in journals not specifically classified as evolutionary. Here I present, for a wide range of journals, an analysis of the number of evolutionary papers they publish and their average impact. I show that there are large differences in impact among evolutionary and non-evolutionary papers within journals; while the impact of evolutionary papers published in multidisciplinary journals is substantially overestimated by their overall impact factor, the impact of evolutionary papers in many of the more specialized, non-evolutionary journals is significantly underestimated. This suggests that, for evolutionary biologists, publishing in high-impact multidisciplinary journals should not receive as much weight as it does now, while evolutionary papers in more narrowly defined journals are currently undervalued. Importantly, however, their ranking remains largely unaffected. While journal impact factors may thus indeed provide a meaningful qualitative measure of impact, a fair quantitative comparison requires a more sophisticated journal classification system, together with multiple field

  17. Introduction: integrating genetic and cultural evolutionary approaches to language.

    Science.gov (United States)

    Mesoudi, Alex; McElligott, Alan G; Adger, David

    2011-04-01

    The papers in this special issue of Human Biology address recent research in the field of language evolution, both the genetic evolution of the language faculty and the cultural evolution of specific languages. While both of these areas have received increasing interest in recent years, there is also a need to integrate these somewhat separate efforts and explore the relevant gene-culture coevolutionary interactions. Here we summarize the individual contributions, set them in the context of the wider literature, and identify outstanding future research questions. The first set of papers concerns the comparative study of nonhuman communication in primates and birds from both a behavioral and neurobiological perspective, revealing evidence for several common language-related traits in various nonhuman species and providing clues as to the evolutionary origin and function of the human language faculty. The second set of papers discusses the consequences of viewing language as a culturally evolving system in its own right, including claims that this removes the need for strong genetic biases for language acquisition, and that phylogenetic evolutionary methods can be used to reconstruct language histories. We conclude by highlighting outstanding areas for future research, including identifying the precise selection pressures that gave rise to the language faculty in ancestral hominin species, and determining the strength, domain specificity, and origin of the cultural transmission biases that shape languages as they pass along successive generations of language learners.

  18. Goldfish morphology as a model for evolutionary developmental biology.

    Science.gov (United States)

    Ota, Kinya G; Abe, Gembu

    2016-01-01

    Morphological variation of the goldfish is known to have been established by artificial selection for ornamental purposes during the domestication process. Chinese texts that date to the Song dynasty contain descriptions of goldfish breeding for ornamental purposes, indicating that the practice originated over one thousand years ago. Such a well-documented goldfish breeding process, combined with the phylogenetic and embryological proximities of this species with zebrafish, would appear to make the morphologically diverse goldfish strains suitable models for evolutionary developmental (evodevo) studies. However, few modern evodevo studies of goldfish have been conducted. In this review, we provide an overview of the historical background of goldfish breeding, and the differences between this teleost and zebrafish from an evolutionary perspective. We also summarize recent progress in the field of molecular developmental genetics, with a particular focus on the twin-tail goldfish morphology. Furthermore, we discuss unanswered questions relating to the evolution of the genome, developmental robustness, and morphologies in the goldfish lineage, with the goal of blazing a path toward an evodevo study paradigm using this teleost species as a new model species. For further resources related to this article, please visit the WIREs website. PMID:26952007

  19. A psychological perspective on the source and function of religion

    OpenAIRE

    Karen van der Merwe

    2010-01-01

    This article explored psychological perspectives on the following: the reasons for humans' religiousness, the influence of religion on people's perspective on life and the importance of understanding the impact of religion on the lives of people. Theories, including psychoanalytical and evolutionary answers regarding the origin of human's penchant to be religious were discussed. Subsequently, the focus was on the dominant influence of religious notions in people's worldview, providing meaning...

  20. The Evolutionary Origins of Hierarchy.

    Directory of Open Access Journals (Sweden)

    Henok Mengistu

    2016-06-01

    Full Text Available Hierarchical organization-the recursive composition of sub-modules-is ubiquitous in biological networks, including neural, metabolic, ecological, and genetic regulatory networks, and in human-made systems, such as large organizations and the Internet. To date, most research on hierarchy in networks has been limited to quantifying this property. However, an open, important question in evolutionary biology is why hierarchical organization evolves in the first place. It has recently been shown that modularity evolves because of the presence of a cost for network connections. Here we investigate whether such connection costs also tend to cause a hierarchical organization of such modules. In computational simulations, we find that networks without a connection cost do not evolve to be hierarchical, even when the task has a hierarchical structure. However, with a connection cost, networks evolve to be both modular and hierarchical, and these networks exhibit higher overall performance and evolvability (i.e. faster adaptation to new environments. Additional analyses confirm that hierarchy independently improves adaptability after controlling for modularity. Overall, our results suggest that the same force-the cost of connections-promotes the evolution of both hierarchy and modularity, and that these properties are important drivers of network performance and adaptability. In addition to shedding light on the emergence of hierarchy across the many domains in which it appears, these findings will also accelerate future research into evolving more complex, intelligent computational brains in the fields of artificial intelligence and robotics.

  1. Evolutionary theory and the naturalist fallacy

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh

    2008-01-01

    The article is an invited response to a target article by Joseph Carroll entitled "An evolutionary paradigm for literary study". It argues that the target article  misuse the fact that works of art are based on adaptations that were fitness-enhancing in the era of evolutionary adaptations to claim...... that great work of art are also automatically fitness-enhancing in the present day environment, at that there are simple correllations between whether a work of art has a high aesthetic value and whether it is fitness-enhancing or not.  Keywords :  Evolutionary aesthetics, film theory, literary theory...

  2. FEZ2 has acquired additional protein interaction partners relative to FEZ1: functional and evolutionary implications.

    Directory of Open Access Journals (Sweden)

    Marcos R Alborghetti

    Full Text Available BACKGROUND: The FEZ (fasciculation and elongation protein zeta family designation was purposed by Bloom and Horvitz by genetic analysis of C. elegans unc-76. Similar human sequences were identified in the expressed sequence tag database as FEZ1 and FEZ2. The unc-76 function is necessary for normal axon fasciculation and is required for axon-axon interactions. Indeed, the loss of UNC-76 function results in defects in axonal transport. The human FEZ1 protein has been shown to rescue defects caused by unc-76 mutations in nematodes, indicating that both UNC-76 and FEZ1 are evolutionarily conserved in their function. Until today, little is known about FEZ2 protein function. METHODOLOGY/PRINCIPAL FINDINGS: Using the yeast two-hybrid system we demonstrate here conserved evolutionary features among orthologs and non-conserved features between paralogs of the FEZ family of proteins, by comparing the interactome profiles of the C-terminals of human FEZ1, FEZ2 and UNC-76 from C. elegans. Furthermore, we correlate our data with an analysis of the molecular evolution of the FEZ protein family in the animal kingdom. CONCLUSIONS/SIGNIFICANCE: We found that FEZ2 interacted with 59 proteins and that of these only 40 interacted with FEZ1. Of the 40 FEZ1 interacting proteins, 36 (90%, also interacted with UNC-76 and none of the 19 FEZ2 specific proteins interacted with FEZ1 or UNC-76. This together with the duplication of unc-76 gene in the ancestral line of chordates suggests that FEZ2 is in the process of acquiring new additional functions. The results provide also an explanation for the dramatic difference between C. elegans and D. melanogaster unc-76 mutants on one hand, which cause serious defects in the nervous system, and the mouse FEZ1 -/- knockout mice on the other, which show no morphological and no strong behavioural phenotype. Likely, the ubiquitously expressed FEZ2 can completely compensate the lack of neuronal FEZ1, since it can interact with all FEZ

  3. Bioinformatic analysis of the neprilysin (M13 family of peptidases reveals complex evolutionary and functional relationships

    Directory of Open Access Journals (Sweden)

    Pinney John W

    2008-01-01

    Full Text Available Abstract Background The neprilysin (M13 family of endopeptidases are zinc-metalloenzymes, the majority of which are type II integral membrane proteins. The best characterised of this family is neprilysin, which has important roles in inactivating signalling peptides involved in modulating neuronal activity, blood pressure and the immune system. Other family members include the endothelin converting enzymes (ECE-1 and ECE-2, which are responsible for the final step in the synthesis of potent vasoconstrictor endothelins. The ECEs, as well as neprilysin, are considered valuable therapeutic targets for treating cardiovascular disease. Other members of the M13 family have not been functionally characterised, but are also likely to have biological roles regulating peptide signalling. The recent sequencing of animal genomes has greatly increased the number of M13 family members in protein databases, information which can be used to reveal evolutionary relationships and to gain insight into conserved biological roles. Results The phylogenetic analysis successfully resolved vertebrate M13 peptidases into seven classes, one of which appears to be specific to mammals, and insect genes into five functional classes and a series of expansions, which may include inactive peptidases. Nematode genes primarily resolved into groups containing no other taxa, bar the two nematode genes associated with Drosophila DmeNEP1 and DmeNEP4. This analysis reconstructed only one relationship between chordate and invertebrate clusters, that of the ECE sub-group and the DmeNEP3 related genes. Analysis of amino acid utilisation in the active site of M13 peptidases reveals a basis for their biochemical properties. A relatively invariant S1' subsite gives the majority of M13 peptidases their strong preference for hydrophobic residues in P1' position. The greater variation in the S2' subsite may be instrumental in determining the specificity of M13 peptidases for their substrates

  4. Evolutionary origins of leadership and followership.

    Science.gov (United States)

    Van Vugt, Mark

    2006-01-01

    Drawing upon evolutionary logic, leadership is reconceptualized in terms of the outcome of strategic interactions among individuals who are following different, yet complementary, decision rules to solve recurrent coordination problems. This article uses the vast psychological literature on leadership as a database to test several evolutionary hypotheses about the origins of leadership and followership in humans. As expected, leadership correlates with initiative taking, trait measures of intelligence, specific task competencies, and several indicators of generosity. The review finds no link between leadership and dominance. The evolutionary analysis accounts for reliable age, health, and sex differences in leadership emergence. In general, evolutionary theory provides a useful, integrative framework for studying leader-follower relationships and generates various novel research hypotheses. PMID:17201593

  5. Evolutionary Topology Optimization for Heat Conduction Fields

    Institute of Scientific and Technical Information of China (English)

    LI Jiachun; YE Bangyan; TANG Yong; GUAN Qiming; YANG Xudong

    2006-01-01

    An effective evolutionary method for solving the structural topology design problems of heat conductive fields is presented in this paper. The topology optimization model based on minimizing the heat transport potential capacity dissipation of heat conductive field is then established and the corresponding sensitivity of objective function is derived to determine which elements would be removed of the heat conductive field for having the increment of the objective heat transport potential capacity dissipation minimized. A Filtering technique is employed in sensitivity field to eliminate numerical instabilities in the evolutionary procedure. Numerical examples are presented to demonstrate the validity and the engineering applicability of the evolutionary method by contrast with SIMP method, meanwhile we can come to a conclusion that higher speed of convergence and clearer optimal topology distribution without intermediate elements can be attained by using evolutionary strategy, with the results laying a reliable foundation for the subsequent shape and size optimizations in thermal engineering.

  6. How mutation affects evolutionary games on graphs.

    Science.gov (United States)

    Allen, Benjamin; Traulsen, Arne; Tarnita, Corina E; Nowak, Martin A

    2012-04-21

    Evolutionary dynamics are affected by population structure, mutation rates and update rules. Spatial or network structure facilitates the clustering of strategies, which represents a mechanism for the evolution of cooperation. Mutation dilutes this effect. Here we analyze how mutation influences evolutionary clustering on graphs. We introduce new mathematical methods to evolutionary game theory, specifically the analysis of coalescing random walks via generating functions. These techniques allow us to derive exact identity-by-descent (IBD) probabilities, which characterize spatial assortment on lattices and Cayley trees. From these IBD probabilities we obtain exact conditions for the evolution of cooperation and other game strategies, showing the dual effects of graph topology and mutation rate. High mutation rates diminish the clustering of cooperators, hindering their evolutionary success. Our model can represent either genetic evolution with mutation, or social imitation processes with random strategy exploration.

  7. Evolutionary Theories of Aging and Longevity

    Directory of Open Access Journals (Sweden)

    Leonid A. Gavrilov

    2002-01-01

    Full Text Available The purpose of this article is to provide students and researchers entering the field of aging studies with an introduction to the evolutionary theories of aging, as well as to orient them in the abundant modern scientific literature on evolutionary gerontology. The following three major evolutionary theories of aging are discussed: 1 the theory of programmed death suggested by August Weismann, 2 the mutation accumulation theory of aging suggested by Peter Medawar, and 3 the antagonistic pleiotropy theory of aging suggested by George Williams. We also discuss a special case of the antagonistic pleiotropy theory, the disposable soma theory developed by Tom Kirkwood and Robin Holliday. The theories are compared with each other as well as with recent experimental findings. At present the most viable evolutionary theories are the mutation accumulation theory and the antagonistic pleiotropy theory; these theories are not mutually exclusive, and they both may become a part of a future unifying theory of aging.

  8. Still doing evolutionary algorithms with Perl

    CERN Document Server

    Guervos, Juan J Merelo

    2009-01-01

    Algorithm::Evolutionary (A::E from now on) was introduced in 2002, after a talk in YAPC::EU in Munich. 7 years later, A::E is in its 0.67 version (past its "number of the beast" 0.666), and has been used extensively, to the point of being the foundation of much of the (computer) science being done by our research group (and, admittedly, not many others). All is not done, however; now A::E is being integrated with POE so that evolutionary algorithms (EAs) can be combined with all kinds of servers and used in client, servers, and anything in between. In this companion to the talk I will explain what evolutionary algorithms are, what they are being used for, how to do them with Perl (using these or other fine modules found in CPAN) and what evolutionary algorithms can do for Perl at large.

  9. Teaching Evolutionary Theory as General Education.

    Science.gov (United States)

    Todd, Paul

    1984-01-01

    Provides a rationale for including evolution as part of a college general education curriculum, discussing the content of evolutionary theory, instructional principles, Darwin's contributions, evolution and religion, and the relationship of evolution with current events. (DMM)

  10. Evolutionary Robotics: What, Why, and Where to

    Directory of Open Access Journals (Sweden)

    Stephane eDoncieux

    2015-03-01

    Full Text Available Evolutionary robotics applies the selection, variation, and heredity principles of natural evolution to the design of robots with embodied intelligence. It can be considered as a subfield of robotics that aims to create more robust and adaptive robots. A pivotal feature of the evolutionary approach is that it considers the whole robot at once, and enables the exploitation of robot features in a holistic manner. Evolutionary robotics can also be seen as an innovative approach to the study of evolution based on a new kind of experimentalism. The use of robots as a substrate can help address questions that are difficult, if not impossible, to investigate through computer simulations or biological studies. In this paper we consider the main achievements of evolutionary robotics, focusing particularly on its contributions to both engineering and biology. We briefly elaborate on methodological issues, review some of the most interesting findings, and discuss important open issues and promising avenues for future work.

  11. Challenges and Opportunities of Evolutionary Robotics

    CERN Document Server

    Sofge, D A; Bugajska, M D; Schultz, A C

    2007-01-01

    Robotic hardware designs are becoming more complex as the variety and number of on-board sensors increase and as greater computational power is provided in ever-smaller packages on-board robots. These advances in hardware, however, do not automatically translate into better software for controlling complex robots. Evolutionary techniques hold the potential to solve many difficult problems in robotics which defy simple conventional approaches, but present many challenges as well. Numerous disciplines including artificial life, cognitive science and neural networks, rule-based systems, behavior-based control, genetic algorithms and other forms of evolutionary computation have contributed to shaping the current state of evolutionary robotics. This paper provides an overview of developments in the emerging field of evolutionary robotics, and discusses some of the opportunities and challenges which currently face practitioners in the field.

  12. Wolbachia versus dengue: Evolutionary forecasts.

    Science.gov (United States)

    Bull, James J; Turelli, Michael

    2013-01-01

    A novel form of biological control is being applied to the dengue virus. The agent is the maternally transmitted bacterium Wolbachia, naturally absent from the main dengue vector, the mosquito Aedes aegypti. Three Wolbachia-based control strategies have been proposed. One is suppression of mosquito populations by large-scale releases of males incompatible with native females; this intervention requires ongoing releases. The other interventions transform wild mosquito populations with Wolbachia that spread via the frequency-dependent fitness advantage of Wolbachia-infected females; those interventions potentially require just a single, local release for area-wide disease control. One of these latter strategies uses Wolbachia that shortens mosquito life, indirectly preventing viral maturation/transmission. The other strategy uses Wolbachia that block viral transmission. All interventions can be undermined by viral, bacterial or mosquito evolution; viral virulence in humans may also evolve. We examine existing theory, experiments and comparative evidence to motivate predictions about evolutionary outcomes. (i) The life-shortening strategy seems the most likely to be thwarted by evolution. (ii) Mosquito suppression has a reasonable chance of working locally, at least in the short term, but long-term success over large areas is challenging. (iii) Dengue blocking faces strong selection for viral resistance but may well persist indefinitely at some level. Virulence evolution is not mathematically predictable, but comparative data provide no precedent for Wolbachia increasing dengue virulence. On balance, our analysis suggests that the considerable possible benefits of these technologies outweigh the known negatives, but the actual risk is largely unknown. PMID:24481199

  13. Evolutionary biology and life histories

    Directory of Open Access Journals (Sweden)

    Brown, C. R.

    2004-06-01

    Full Text Available The demographic processes that drive the spread of populations through environments and in turn determine the abundance of organisms are the same demographic processes that drive the spread of genes through populations and in turn determine gene frequencies and fitness. Conceptually, marked similarities exist in the dynamic processes underlying population ecology and those underlying evolutionary biology. Central to an understanding of both disciplines is life history and its component demographic rates, such as survival, fecundity, and age of first breeding, and biologists from both fields have a vested interest in good analytical machinery for the estimation and analysis of these demographic rates. In the EURING conferences, we have been striving since the mid 1980s to promote a quantitative understanding of demographic rates through interdisciplinary collaboration between ecologists and statisticians. From the ecological side, the principal impetus has come from population biology, and in particular from wildlife biology, but the importance of good quantitative insights into demographic processes has long been recognized by a number of evolutionary biologists (e.g., Nichols & Kendall, 1995; Clobert, 1995; Cooch et al., 2002. In organizing this session, we have aimed to create a forum for those committed to gaining the best possible understanding of evolutionary processes through the application of modern quantitative methods for the collection and interpretation of data on marked animal populations. Here we present a short overview of the material presented in the session on evolutionary biology and life histories. In a plenary talk, Brown & Brown (2004 explored how mark–recapture methods have allowed a better understanding of the evolution of group–living and alternative reproductive tactics in colonial cliff swallows (Petrochelidon pyrrhonota. By estimating the number of transient birds passing through colonies of different sizes, they

  14. Evolutionary fingerprints in genome-scale networks

    OpenAIRE

    Schütte, Moritz

    2012-01-01

    Mathematical modeling of biological phenomena has experienced increasing interest since new high-throughput technologies give access to growing amounts of molecular data. These modeling approaches are especially able to test hypotheses which are not yet experimentally accessible or guide an experimental setup. One particular attempt investigates the evolutionary dynamics responsible for today's composition of organisms. Computer simulations either propose an evolutionary mechanism and thus re...

  15. Evolutionary food web models in fragmented landscapes

    OpenAIRE

    Allhoff, Korinna Theresa

    2015-01-01

    Ecosystems all over the world currently experience dramatic changes in their environment. The direct consequences are increased extinction rates. Food webs, which are networks of predator-prey interactions, provide a basic understanding of ecosystems and therefore help to identify reasonable conservation strategies. In this thesis, I analyze evolutionary metacommunities, which can be modeled as evolutionary networks of networks: The outer networks represent fragmented landscapes of sever...

  16. Stellar evolutionary models: uncertainties and systematics

    OpenAIRE

    Cassisi, S.

    2005-01-01

    In this last decade, our knowledge of evolutionary and structural properties of stars of different mass and chemical composition is significantly improved. This result has been achieved as a consequence of our improved capability in understanding and describing the physical behavior of stellar matter in the different thermal regimes characteristic of the different stellar mass ranges and/or evolutionary stages. This notwithstanding, current generation of stellar models is still affected by si...

  17. Hybrid evolutionary algorithms to solve scheduling problems

    OpenAIRE

    Minetti, Gabriela F.; Salto, Carolina; Bermúdez, Carlos; Fernandez, Natalia; Alfonso, Hugo; Gallard, Raúl Hector

    2002-01-01

    The choice of a search algorithm can play a vital role in the success of a scheduling application. Evolutionary algorithms (EAs) can be used to solve this kind of combinatorial optimization problems. Compared to conventional heuristics (CH) and local search techniques (LS), EAs are not well suited for fine-tuninf those structures, which are very close to optimal solutions. Therefore, in complex problems, it is essential to build hybrid evolutionary algorithms (HEA) by incorporating CH and/or ...

  18. Improving DNA Computing Using Evolutionary Techniques

    OpenAIRE

    Godar J. Ibrahim; Tarik A. Rashid; Ahmed T. Sadiq

    2016-01-01

    the field of DNA Computing has attracted many biologists and computer scientists as it has a biological interface, small size and substantial parallelism. DNA computing depends on DNA molecules’ biochemical reactions which they can randomly anneal and they might accidentally cause improper or unattractive computations. This will inspire opportunities to use evolutionary computation via DNA. Evolutionary Computation emphasizes on probabilistic search and optimization methods which are mimickin...

  19. Stochastic evolutionary dynamics of direct reciprocity

    OpenAIRE

    Lorens A. Imhof; Nowak, Martin A.

    2009-01-01

    Evolutionary game theory is the study of frequency-dependent selection. The success of an individual depends on the frequencies of strategies that are used in the population. We propose a new model for studying evolutionary dynamics in games with a continuous strategy space. The population size is finite. All members of the population use the same strategy. A mutant strategy is chosen from some distribution over the strategy space. The fixation probability of the mutant strategy in the reside...

  20. The evolutionary position of turtles revised

    OpenAIRE

    Zardoya, Rafael; Meyer, Axel

    2001-01-01

    Consensus on the evolutionary position of turtles within the amniote phylogeny has eluded evolutionary biologists for more than a century. This phylogenetic problem has remained unsolved partly because turtles have such a unique morphology that only few characters can be used to link them with any other group of amniotes. Among the many alternative hypotheses that have been postulated to explain the origin and phylogenetic relationships of turtles, a general agreement among paleontologists em...