共查询到20条相似文献,搜索用时 15 毫秒
1.
Balaban E 《The International journal of developmental biology》2005,49(2-3):117-124
Working together at Nogent, Marie-Aimee Teillet, Nicole Le Douarin and the author successfully developed an extension of the quail-chick transplant technique for relating species brain cell differences to behavioral differences. This article reviews the application of the technique to species differences in motor behavior (crowing) and auditory perceptual preferences. Interspecies brain transplants provide a unique means for elucidating general cellular mechanisms which integrate evolutionary and individual experience during the development of complex brain circuitry. 相似文献
2.
Helliwell JF Putnam RD 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2004,359(1449):1435-1446
Large samples of data from the World Values Survey, the US Benchmark Survey and a comparable Canadian survey are used to estimate equations designed to explore the social context of subjective evaluations of well-being, of happiness, and of health. Social capital, as measured by the strength of family, neighbourhood, religious and community ties, is found to support both physical health and subjective well-being. Our new evidence confirms that social capital is strongly linked to subjective well-being through many independent channels and in several different forms. Marriage and family, ties to friends and neighbours, workplace ties, civic engagement (both individually and collectively), trustworthiness and trust: all appear independently and robustly related to happiness and life satisfaction, both directly and through their impact on health. 相似文献
3.
Xin Y O'Donnell AH Ge Y Chanrion B Milekic M Rosoklija G Stankov A Arango V Dwork AJ Gingrich JA Haghighi FG 《Epigenetics》2011,6(11):1308-1318
DNA methylation is essential in brain function and behavior; therefore, understanding the role of DNA methylation in brain-based disorders begins with the study of DNA methylation profiles in normal brain. Determining the patterns and scale of methylation conservation and alteration in an evolutionary context enables the design of focused but effective methylation studies of disease states. We applied an enzymatic-based approach, Methylation Mapping Analysis by Paired-end Sequencing (Methyl-MAPS), which utilizes second-generation sequencing technology to provide an unbiased representation of genome-wide DNA methylation profiles of human and mouse brains. In this large-scale study, we assayed CpG methylation in cerebral cortex of neurologically and psychiatrically normal human postmortem specimens, as well as mouse forebrain specimens. Cross-species human-mouse DNA methylation conservation analysis shows that DNA methylation is not correlated with sequence conservation. Instead, greater DNA methylation conservation is correlated with increasing CpG density. In addition to CpG density, these data show that genomic context is a critical factor in DNA methylation conservation and alteration signatures throughout mammalian brain evolution. We identify key genomic features that can be targeted for identification of epigenetic loci that may be developmentally and evolutionarily conserved and wherein aberrations in DNA methylation patterns can confer risk for disease. 相似文献
4.
《Epigenetics》2013,8(11):1308-1318
DNA methylation is essential in brain function and behavior; therefore, understanding the role of DNA methylation in brain-based disorders begins with the study of DNA methylation profiles in normal brain. Determining the patterns and scale of methylation conservation and alteration in an evolutionary context enables the design of focused but effective methylation studies of disease states. We applied an enzymatic-based approach, Methylation Mapping Analysis by Paired-end Sequencing (Methyl-MAPS), which utilizes second-generation sequencing technology to provide an unbiased representation of genome-wide DNA methylation profiles of human and mouse brains. In this large-scale study, we assayed CpG methylation in cerebral cortex of neurologically and psychiatrically normal human postmortem specimens, as well as mouse forebrain specimens. Cross-species human-mouse DNA methylation conservation analysis shows that DNA methylation is not correlated with sequence conservation. Instead, greater DNA methylation conservation is correlated with increasing CpG density. In addition to CpG density, these data show that genomic context is a critical factor in DNA methylation conservation and alteration signatures throughout mammalian brain evolution. We identify key genomic features that can be targeted for identification of epigenetic loci that may be developmentally and evolutionarily conserved and wherein aberrations in DNA methylation patterns can confer risk for disease. 相似文献
5.
JJ Mitteldorf 《Biochemistry. Biokhimii?a》2012,77(7):716-725
Compelling evidence for an adaptive origin of aging has clashed with traditional evolutionary theory based on exclusively individual selection. The consensus view has been to try to understand aging in the context of a narrow, restrictive evolutionary paradigm, called the Modern Synthesis, or neo-Darwinism. But neo-Darwinism has shown itself to be inadequate in other ways, failing to account for stable ecosystems, for the evolution of sex and the maintenance of diversity and the architecture of the genome, which appears to be optimized for evolvability. Thus aging is not the only reason to consider overhauling the standard theoretical framework. Selection for stable ecosystems is rapid and efficient, and so it is the easiest modification of the neo-Darwinian paradigm to understand and to model. Aging may be understood in this context. More profound and more mysterious are the ways in which the process of evolution itself has been transformed in a bootstrapping process of selection for evolvability. Evolving organisms have learned to channel their variation in ways that are likely to enhance their long-term prospects. This is an expanded notion of fitness. Only in this context can the full spectrum of sophisticated adaptations be understood, including aging, sex, diversity, ecological interdependence, and the structure of the genome. 相似文献
6.
R I Dunbar 《Folia primatologica; international journal of primatology》1989,53(1-4):235-246
I argue that one of the strong features in disciplines like molecular biology and cosmology is the extent ot which they use a powerful theoretical framework to generate and test quantitative predictions. Studies of biological evolution can exploit a similar advantage by integrating our current understanding of physiological and sociobiological processes to generate models of much greater sophistication than has commonly been the practice hitherto. I illustrate this with a number of examples drawn from the evolutionary biology of human and nonhuman primates. 相似文献
7.
Plastids are derived from free-living cyanobacteria that were engulfed by eukaryotic host cells through the process of endosymbiosis and, like their cyanobacterial ancestors, divide by binary fission. Over the last decade the continued identification and functional analysis of plastid division components, coupled with ever-increasing genomic resources, have yielded insights into the origins and evolution of the plastid division mechanism in higher plants. Here we review the current understanding of the evolution of the chloroplast division proteins and present a model of how the machinery has developed to execute plastid division in Arabidopsis. 相似文献
8.
The nuclear lamina is composed mainly of lamins A and C (A-type lamins) and lamins B1 and B2 (B-type lamins). Dogma has held that lamins B1 and B2 play unique and essential roles in the nucleus of every eukaryotic cell. Recent studies have raised doubts about that view but have uncovered crucial roles for lamins B1 and B2 in neuronal migration during the development of the brain. The relevance of lamins A and C in the brain remains unclear, but it is intriguing that prelamin A expression in the brain is low and is regulated by miR-9, a brain-specific microRNA. 相似文献
9.
Mira Crouch 《Human nature (Hawthorne, N.Y.)》1999,10(2):163-182
“Postnatal depression” denotes the syndrome of dysphoria, debility, and anxiety that follows childbirth in about 10–20% of women (as variously estimated). Its etiology is seen to be lodged in a variety of psychosocial as well as biological factors, among which the isolating and pressured culture of contemporary society (especially for women/mothers) is commonly singled out as a powerful precipitator. This view is extended here through the evolutionary perspective which casts maternal distress as a set of adaptive responses with the function, in ancestral environments, of soliciting support for a mother who feels that her maternal responsiveness may be threatened. As continuous caretaking of the infant is the active expression of evolved maternal responsiveness, departures from this pattern result in anxiety and distress that seek resolution. Manifestations of maternal distress in contemporary society are dysfunctional, however, since the present social structure does not provide spontaneous and immediate support that can spring forth within small, closely knit social units. Furthermore, for present-day mothers distress is self-perpetuating since the ingrained tendency toward continuing responsiveness rarely finds practical expression and is thus converted into anxious vigilance and depression. This view generates the hypothesis that the emotional and cognitive contents of maternal vigilance are associated with the needs of the infant and will therefore be focused on crying and feeding. A number of qualitative studies of women’s experiences during the postpartum bear out this prediction and support the feasibility of the evolutionary hypothesis of “postnatal depression” as a set of adaptive responses, now out of place in a novel environment. 相似文献
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N. V. Volodko N. P. Eltsov E. B. Starikovskaya R. I. Sukernik 《Russian Journal of Genetics》2009,45(7):870-874
Based on the mtDNA first hypervariable segment sequence variation data, statistical analysis of the diversity in Yukaghirs in comparison with the other indigenous populations of Siberia, was carried out. The level of the Yukaghir mtDNA gene diversity (GD) constituted 0.920, which was only slightly different from the corresponding estimate for the other Siberian populations. Integral estimates of the genetic structure of Siberian populations (k, S, θ S , and π) are presented. Phylogenetic analysis, performed using the neighbor-joining method, showed that the Siberian populations clustered irrespectively to their language affiliation. Negative F s values found in Yukaghirs pointed to the possible influence of adaptive selection. 相似文献
13.
Bird-pollinated flowers in an evolutionary and molecular context 总被引:2,自引:0,他引:2
Evolutionary shifts to bird pollination (ornithophily) haveoccurred independently in many lineages of flowering plants.This shift affects many floral features, particularly thoseresponsible for the attraction of birds, deterrence of illegitimateflower visitors (particularly bees), protection from vigorousforaging by birds, and accurate placement of pollen on bird'sbodies. Red coloration appears to play a major role in bothbee-deterrence and bird-attraction. Other mechanisms of bird-attractioninclude the production of abundant dilute nectar and the provisionof secondary perches (for non-hovering birds). As a result ofselection for similar phenotypic traits in unrelated bird-pollinatedspecies, a floral syndrome of ornithophily can be recognized,and this review surveys the component floral traits. The strongconvergent evolution evident in bird-pollinated flowers raisesa question about the nature of the genetic mechanisms underlyingsuch transitions and whether the same gene systems are involvedin most cases. As yet there is too little information to answerthis question. However, some promising model systems have beendeveloped that include closely related bee and bird-pollinatedflowers, such as Ipomoea, Mimulus, and Lotus. Recent studiesof floral developmental genetics have identified numerous genesimportant in the development of the floral phenotype, whichare also potential candidates for involvement in shifts betweenbee-pollination and bird pollination. As more whole-genome informationbecomes available, progress should be rapid. Key words: Anthocyanin pigmentation, bird-pollination, candidate gene, developmental genetics, honey-eaters, hummingbirds, nectar, ornithophily, pollination syndrome, sunbirds
Received 2 November 2007; Revised 21 December 2007 Accepted 7 January 2008 相似文献
14.
We describe a new hypothesis for the development of autism, that it is driven by imbalances in brain development involving enhanced effects of paternally expressed imprinted genes, deficits of effects from maternally expressed genes, or both. This hypothesis is supported by: (1) the strong genomic-imprinting component to the genetic and developmental mechanisms of autism, Angelman syndrome, Rett syndrome and Turner syndrome; (2) the core behavioural features of autism, such as self-focused behaviour, altered social interactions and language, and enhanced spatial and mechanistic cognition and abilities, and (3) the degree to which relevant brain functions and structures are altered in autism and related disorders. The imprinted brain theory of autism has important implications for understanding the genetic, epigenetic, neurological and cognitive bases of autism, as ultimately due to imbalances in the outcomes of intragenomic conflict between effects of maternally vs. paternally expressed genes. 相似文献
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Thoughts on clonal integration: Facing the evolutionary context 总被引:4,自引:0,他引:4
Colleen K. Kelly 《Evolutionary ecology》1995,9(6):575-585
Summary In this essay, I have pointed out that the appropriate evolutionary context for plant clonality dictates a focus on the impact of the derived trait of potential independence of subunits on the evolutionarily primitive trait of obligate interdependence of plant subunits, i.e. the advantages of independence. This fact prescribes a major shift in approach from previous lines of investigation which have assumed that clonal plants should fall apart and sought to determine the advantages of interdependence. The delineated reorientation calls for a significant change in the investigation of the ecology of clonality in higher plants, emphasizing factors that select for physical and physiological disintegration of the genet and de-emphasizing the need to derive ecological explanations for properties a plant will possess entirely by reason of its phylogenetic and developmental heritage. I suggest that (1) patterns of ramet independence may result from selective pressures on the cost of interconnections (2) programmed ramet independendence may be a response to the selective pressure of a high possibility of traumatic breakage and (3) programmed ramet independence may allow escape of the genet from mortality due to pathogen infestation. 相似文献
17.
Pete C. Trimmer James A.R. Marshall Lutz Fromhage John M. McNamara Alasdair I. Houston 《Evolution and human behavior》2013,34(1):8-15
A placebo is a treatment which is not effective through its direct action on the body, but works because of its effect on the patient's beliefs. From an evolutionary perspective, it is initially puzzling why, if people are capable of recovering, they need a placebo to do so. Based on an argument put forward by Humphrey [Great expectations: the evolutionary psychology of faith-healing and the placebo effect. In: Humphrey, N (2002). The mind made flesh. Oxford University Press, Oxford. 255–285], we present simple mathematical models of the placebo effect that involve a trade-off between the costs and benefits of allocating resources to a current problem. These models show why the effect occurs and how its magnitude and timing can depend on different factors. We identify a particular aspect of belief which may govern the effect and conclude that a deeper understanding of why the placebo effect exists may allow it to be invoked more easily in the future. 相似文献
18.
Conrad M 《Bio Systems》1999,52(1-3):99-110
Proteins and nucleic acids constitute a vast potential reservoir of pattern recognizers that operate on the basis of shape complementarity. It is possible to construct models of computing in which these shape-based interactions contribute directly to recognition of signal patterns at the device (or cell) level. The input-output transform is molded by variation-selection evolution. Such models provide clues as to the organizational features that enable biomolecular matter to acquire nonevolutionary modes of problem solving through the evolutionary process. The requisite organizations are characterized by a high dimensionality that allows them to simultaneously exhibit aspects of context-sensitivity and context-independence. 相似文献
19.
We consider the substitution model T92+CpG of DNA sequence evolution which takes into account the hypermutability of CpG dinucleotides, an effect that can be especially observed in vertebrate genomes. We provide an exact method to simulate the evolution of finite DNA sequences under this model and numerical procedures to infer evolutionary times in two cases: between an ancestral and a present sequence and between two homologous sequences. We show on simulated data that our new numerical method yields very accurate estimations of divergence times. In a context of strong CpG hypermutability, it clearly outperforms the classical estimation procedure that is solely based on the model T92 without CpG influence. Supplementary Material is available at www.liebertonline.com/cmb . 相似文献
20.
Warren D. Allmon 《Evolutionary ecology》1994,8(2):95-112
Summary A traditional focus of evolutionary paleoecology has been the reconstruction of the selective forces that have affected evolving lineages through time. If the history of those lineages is dominated by stasis and punctuation, however, this is at best an inadequate and at worst a misdirected research strategy for macroevolution, because long-term stasis implies that environmental factors may have less influence on evolving lineages than previously believed. Such reasoning has led some proponents of punctuated views to reject ecological interactions as predominant or even significant forces in evolution. This is not a necessary conclusion. It is possible to accept the empirical predominance of stasis in evolution and at the same time the importance of ecology in affecting the course of evolutionary trends within lineages. If stasis prevails, ecology matters in the evolution of lineages if either (1) stabilizing selection is an important cause of stasis or (2) ecological interactions play an important role in controlling the speciation process. Viewing allopatric speciation explicitly as a three-stage process (consisting of formation, persistence and differentiation of isolated populations) clarifies testing of the role of ecology in speciation and may redirect clade-specific evolutionary paleoecology towards more enlightening interaction with other areas of macroevolutionary study. 相似文献