SEARCH · Search PubMed

Results for “social evolution”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources

PubMed1992

Mechanisms of adaptive evolution. Darwinism and Lamarckism restated.

This article discusses the conceptual basis of the different mechanisms of adaptive evolution. It is argued that only two such mechanisms may conceivably exist, Lamarckism and Darwinism. Darwinism is the fundamental process generating the diversity of species. Some aspects of the gene-centered approach to Darwinism are questioned, since they do not account for the generation of biological diversity. Diversity in biological design must be explained in relation to the diversity of interactions of organisms (or other higher-level units) with their environment. This aspect is usually overlooked in gene-centered views of evolution. A variant of the gene-selectionist approach has been proposed to account for the spread of cultural traits in human societies. Alternatively, I argue that social evolution is rather driven by what I call pseudo-Lamarckian inheritance. Finally, I argue that Lamarckian and pseudo-Lamarckian inheritance are just special cases of faithful replication which are found in the development of some higher-order units, such as multicellular organisms and human societies.

Adaptation, Physiological↗

PubMed2001

Molecular ecology of social behaviour: analyses of breeding systems and genetic structure.

Molecular genetic studies of group kin composition and local genetic structure in social organisms are becoming increasingly common. A conceptual and mathematical framework that links attributes of the breeding system to group composition and genetic structure is presented here, and recent empirical studies are reviewed in the context of this framework. Breeding system properties, including the number of breeders in a social group, their genetic relatedness, and skew in their parentage, determine group composition and the distribution of genetic variation within and between social units. This group genetic structure in turn influences the opportunities for conflict and cooperation to evolve within groups and for selection to occur among groups or clusters of groups. Thus, molecular studies of social groups provide the starting point for analyses of the selective forces involved in social evolution, as well as for analyses of other fundamental evolutionary problems related to sex allocation, reproductive skew, life history evolution, and the nature of selection in hierarchically structured populations. The framework presented here provides a standard system for interpreting and integrating genetic and natural history data from social organisms for application to a broad range of evolutionary questions.

Animals↗

PubMed2001

Restricted effective queen dispersal at a microgeographic scale in polygynous populations of the ant Formica exsecta.

Ecological constraints on effective dispersal have been suggested to be a key factor influencing social evolution in animal societies as well as the shift from single queen colonies (monogyny) to multiple queen colonies (polygyny) in ants. However, little is known about the effective dispersal patterns of ant queens. Here we investigate the microgeographic genetic structure of mitochondrial haplotypes in polygynous populations of the ant Formica exsecta, both between pastures and among nests within pastures. An analysis of molecular variance revealed a very high genetic differentiation (phiST = 0.72) between pastures, indicating that queens rarely disperse successfully between pastures, despite the fact that pastures were sometimes as close as 1 km. Most of the pastures contained only a single haplotype, and haplotypes were frequently distinct between nearby pastures and even between groups of nests within the same pasture. In the three pastures that contained several haplotypes, haplotypes were not randomly distributed, the genetic differentiation between nests being phiST = 0.17, 0.52, and 0.69. This indicates that most queens are recruited within their parental colonies. However, a large proportion of nests contained more than one haplotype, demonstrating that colonies will sometimes accept foreign queens. The relatedness of mitochondrial genes among nestmates varied between 0.62 and 0.75 when relatedness was measured within each pasture and ranged between 0.72 and 1.0 when relatedness was assessed with all pastures as a reference population. Neighboring nests were more genetically similar than distant ones, and there was significant isolation by distance. This pattern may be due to new nests being formed by budding or by limited effective queen dispersal, probably on foot between neighboring nests. These results show that effective queen dispersal is extremely restricted even at a small geographical scale, a pattern consistent with the idea that ecological constraints are an important selective force leading to the evolution and maintenance of polygyny.

Animals↗

PubMed1996

Aggression from a developmental perspective: genes, environments and interactions.

Genetic influences on the social behaviours of non-human mammals are ubiquitous, powerful and readily detected. But demonstrations that social behaviours are influenced by genes constitute only part of the story. Developmental findings have helped complete the picture. Specifically, these studies show that: (1) genetic effects for aggressive behaviours are highly malleable over the course of development; (2) genetic influences on aggressive behaviour are more dynamic, easily achieved and open to rapid manipulation than has been recognized in current models of social evolution and behavioural genetics; (3) developmental timing has a significant impact upon the nature of the genetic effects observed in aggressive behaviours. These empirical results are consistent with the view that social behaviours are among the first features to be influenced by genetic selection and by environmental experience. Social actions have distinctive properties in adaptation because they organize the space between the organism and the environment and promote rapid, selective and novel accommodations. The modern integrative view of the development of individual-in-context brings attention to the correlation between constraints within and external to individuals. This paper reviews findings on how these processes become integrated over time in individuals and species, and their implications for the nurture of nature.

Aggression↗

PubMed1981

[Evolution of borderline states].

This study presents all the anamnestic, clinical and catamnestic data and information regarding 111 patients diagnosed as Borderline in patients. The research confirms the assertion of various authors concerning the existence, in the daily clinical practice, of a Borderline psychopathological group, distinct and autonomous, comprising patients who present psycho-affectives and social specific features and often manifest typical depressed and psychotic syndromes; the statistical survey shows the heuristic interest of the Borderline diagnostic since several social and cultural as personal and familiar psychopathological variable factors appeared to be determinant in what concerns the psycho-social evolution of these patients.

Adult↗

PubMed2003

Social insect networks.

Social insect colonies have many of the properties of adaptive networks. The simple rules governing how local interactions among individuals translate into group behaviors are found across social groups, giving social insects the potential to have a profound impact on our understanding of the interplay between network dynamics and social evolution.

Animals↗

PubMed2005

Bivoltinism as an antecedent to eusociality in the paper wasp genus Polistes.

To learn the evolutionary trajectories of caste differentiation in eusocial species is a major goal of sociobiology. We present an explanatory framework for caste evolution in the eusocial wasp genus Polistes (Vespidae), which is a model system for insect eusocial evolution. We hypothesize that Polistes worker and gyne castes stem from two developmental pathways that characterized the bivoltine life cycle of a solitary ancestor. Through individual-based simulations, we show that our mechanistic framework can reproduce colony-level characteristics of Polistes and, thereby, that social castes can emerge from solitary regulatory pathways. Our explanatory framework illustrates, by specific example, a changed perspective for understanding insect social evolution.

Animals↗

PubMed2005

Chronologic history of occupational medicine.

OBJECTIVES: To provide a chronologic review of growing knowledge in occupational medicine relating work and work hazards to health, and to provide a perspective on the lessons learned from the frequent inattention or misrepresentation of hazards. METHODS: Many books on the social and medical history of work including epidemiology and toxicology were reviewed, as well as published papers and interviews. RESULTS: Throughout history workplace hazards and occupational medicine have been shaped by the forces that shape work itself, social evolution, changing modes of production, shifting economic powers, and demographic changes in the workforce. Lest we think these changes are unique to the present time, this paper emphasizes the long-term and inevitable relationship between social structure and worker health. Hippocrates emphasized the relation between environment (air and water) and health, although he has less to say about the non-military work environment, perhaps because of the denigration of manual labor in Greece. The impact of work on health can be traced to the Edwin Smith Surgical Papyrus, written approximately 1700 BC. The earliest occupational physicians served military forces, and Galen was physician to Roman gladiators. Finger and wrist guards worn by Bronze Age archers represent early personal protective equipment. Writers of the classic period mention diseases and hazards of miners, and Pliny (1st century AD) mentions veils to cover the face. In the Middle East Rhazes included occupation in his case studies (9th century). Paracelsus, and Agricola were prominent, figures in the 15th century, with an emphasis on mining and health. Ramazzini's (c1700) work was widely translated in ensuing decades and is now well-known to all, but its influence between about 1800 and 1940 is inapparent. The emergence of a public health movement in the mid-1800s focused attention on the abominable conditions of many factories and on the living conditions, poor nutrition, high stress, poverty and ill health of the new factory working class, while paying scant attention to specific workplace hazards. CONCLUSIONS: The recognition of occupational diseases in the United States has often lagged by a generation behind the recognition of the same diseases in Europe. We are now into a second industrial revolution led by multinational corporations and information technology, shifting production facilities, and jobs moving around the world in search of cheap labor in the countries with the fastest growing population and the greatest poverty. Occupational medicine must be alert to the new challenges imposed by this revolution.

Adult↗

PubMed2001

Human ageing and the origins of religion.

During the evolution of hominids, the population could be sustained even with an expectation of life at birth of less than 20 years. Under these circumstances very few individuals reached old age. In these hunter-gatherer communities, altruistic behaviour was encouraged because it increased the likelihood of survival, whereas self-interest did not. An early moral code benefited the community as a whole. As social evolution progressed, the chances of survival increased, and for the first time very elderly individuals appeared. However, the reward for survival to old age was merely decrepitude and death. Under these circumstances, new incentives became a social necessity, and these took the form of a belief in an eternal afterlife. Religion then became the basis for the moral code, and it provided an assurance of continual survival after death.

Aging↗

PubMed2001

The marine food chain in relation to biodiversity.

Biodiversity provides "raw materials" for the food chain and seafood production, and also influences the capacity of ecosystems to perform these and other services. Harvested marine seafood species now exceed 100 million t y(-1) and provide about 6% of all protein and 17% of animal protein consumed by humans. These resources include representatives from about nine biologically diverse groups of plants and animals. Fish account for most of the world"s marine catches, of which only 40 species are taken in abundance. Highest primary productivity and the richest fisheries are found within Exclusive Economic Zones (EEZ). This narrow strip (200 nautical mile/370 km wide) is not only the site of coastal "food factories" but also the area associated with heaviest perturbation to the marine environment. Structural redundancy is evident in marine ecosystems, in that many species are interchangeable in the way they characterise assemblage composition. While there is probably functional redundancy within groups, the effects of species loss on ecosystem performance cannot be easily predicted. In particular, the degree to which biodiversity per se is needed for ecosystem services, including seafood/fishery production, is poorly understood. Many human activities, including unsustainable fishing and mariculture, lead to erosion of marine biodiversity. This can undermine the biophysical cornerstones of fisheries and have other undesirable environmental side effects. Of direct concern are "species effects", in particular the removal of target and non-target fishery species, as well as conservationally important fauna. Equally disrupting but less immediate are "ecosystem effects", such as fishing down the food web, following a shift from harvested species of high to low trophic level. Physical and biological disturbances from trawl nets and dynamite fishing on coral reefs can also severely impact ecosystem structure and function. "Broadscale" biological and social effects brought about by fishing carry even more far-reaching consequences. For example, fishing itself can change the age at which sexual maturity is reached, thus affecting the reproductive status of the stock. Hence, fishing may be regarded as a mediator of evolution. Social impacts include conflicts over fish prices and policies arising from heavy fishing and inadequate institutional structures. Measures to increase the sustainability of catches and of biodiversity need to be much more tightly coupled. Promising approaches include use of bio-economic indicators and fully protected marine areas. High- and local-level governance options are also examined. Use of expert systems incorporating "fuzzy logic" are providing useful environmental insights in the ASEAN countries and other parts of the world, and have applications in fishery management and biodiversity conservation.

Animals↗

PubMed2004

From genes to societies.

Research on model organisms has substantially advanced our understanding of aging. However, these studies collectively lack any examination of the element of sociality, an important feature of human biology. Social insects present a number of unique possibilities for investigating social influences on aging and potentially detecting new mechanisms for extremely prolonged, healthy life spans that have evolved naturally. Social evolution has led to life spans in reproductive females that are much longer (up to over 100-fold) than those of males or of nonreproductive worker castes. These differences are particularly dramatic because they are due to environmental influences, as all individuals develop from the same genomes. Social insect colonies consist of semi-autonomous individuals, and the relationship between the colony and the individual creates many interesting predictions in the light of the common theories of aging. Furthermore, the variety of lifestyles of social insects creates the potential for crucial comparative analyses across distinct social systems.

Animals↗

PubMed1999

Phylogeny of the bee genus Halictus (Hymenoptera: halictidae) based on parsimony and likelihood analyses of nuclear EF-1alpha sequence data.

We investigated higher-level phylogenetic relationships within the genus Halictus based on parsimony and maximum likelihood (ML) analysis of elongation factor-1alpha DNA sequence data. Our data set includes 41 OTUs representing 35 species of halictine bees from a diverse sample of outgroup genera and from the three widely recognized subgenera of Halictus (Halictus s.s., Seladonia, and Vestitohalictus). We analyzed 1513 total aligned nucleotide sites spanning three exons and two introns. Equal-weights parsimony analysis of the overall data set yielded 144 equally parsimonious trees. Major conclusions supported in this analysis (and in all subsequent analyses) included the following: (1) Thrincohalictus is the sister group to Halictus s.l., (2) Halictus s.l. is monophyletic, (3) Vestitohalictus renders Seladonia paraphyletic but together Seladonia + Vestitohalictus is monophyletic, (4) Michener's Groups 1 and 3 are monophyletic, and (5) Michener's Group 1 renders Group 2 paraphyletic. In order to resolve basal relationships within Halictus we applied various weighting schemes under parsimony (successive approximations character weighting and implied weights) and employed ML under 17 models of sequence evolution. Weighted parsimony yielded conflicting results but, in general, supported the hypothesis that Seladonia + Vestitohalictus is sister to Michener's Group 3 and renders Halictus s.s. paraphyletic. ML analyses using the GTR model with site-specific rates supported an alternative hypothesis: Seladonia + Vestitohalictus is sister to Halictus s.s. We mapped social behavior onto trees obtained under ML and parsimony in order to reconstruct the likely historical pattern of social evolution. Our results are unambiguous: the ancestral state for the genus Halictus is eusociality. Reversal to solitary behavior has occurred at least four times among the species included in our analysis.

Animals↗

PubMed2004

Phenotypic deconstruction reveals involvement of manganese transporter malvolio in honey bee division of labor.

Molecular analysis of a complex behavioral phenotype is facilitated by dissecting it into simpler behavioral components. Using this approach, we present evidence implicating increased manganese transport by the malvolio (mvl) gene into brain cells as one factor that influences age-related division of labor in honey bee colonies. We studied mvl because manganese affects sucrose responsiveness in Drosophila melanogaster, and sucrose responsiveness is related to division of labor in honey bee colonies. Honey bee foragers are more responsive to sucrose in the laboratory than are younger nurse bees, and pollen foragers are more responsive to sucrose than nectar foragers. Levels of mvl mRNA in the brain and manganese in the head were higher in pollen foragers compared with nurses, with nectar foragers intermediate. Manganese treatment increased honey bee sucrose responsiveness and caused precocious foraging. Manganese levels showed a similar pattern to mvl mRNA but manganese treatment did not increase pollen foraging. These results suggest that, while there are molecular pathways common to sucrose responsiveness and division of labor, linkages between a complex behavior and some of its simpler behavioral components are not obligatory. Together with previous findings, these results support the idea that some feeding-related genes in Drosophila have been used in social evolution to regulate division of labor.

Amino Acid Sequence↗

PubMed2004

The prenatal autistic imprinting hypothesis: developmental maladaptation to the environmental changes between womb and the social world.

Although the importance of biological and genetic aspects of the etiology is well recognized, the pathological process of autism still remains to be elucidated. In contrast to a qualitative dichotomy concept, a dimensional perspective that places the autistic traits as quantitative extremes can easily explain the diversity and subtlety of the clinical features. In a dimensional (quantitative continuum) condition, no single qualitative process can distinguish the extremes from normal variations. In addition, the traditional view, which regards autism as a hypo-reproductive disease with a strong genetic contribution, cannot interpret the recent worldwide prevalence of autism. From a novel viewpoint, we have proposed 'the prenatal autistic imprinting hypothesis' in which autism is regarded as an inevitable consequence of human social evolution in both past and future. Postulated primary phenotypes are closely associated with the autistic savant skills and the autistic adherent temperament, and might increase the chance of specific prenatal experiences, named 'autistic imprinting'. An earlier prenatal brain growth and an earlier establishment of a type of consciousness may be critical for the imprinting process. A postnatal autistic social maladaptation may be a mere outcome of the putative intrauterine behavioral adaptation in individuals with the primary phenotypes. Both an autistic manner of thinking, which is referred to as 'visual thinking', and the prenatal early development of visual cortical architectures may play a key role in the autistic imprinting process.

Adaptation, Physiological↗

PubMed2002

Eusociality in African mole-rats: new insights from patterns of genetic relatedness in the Damaraland mole-rat (Cryptomys damarensis).

After the discovery of eusociality in the naked mole-rat, it was proposed that inbreeding and high colony relatedness in this species were the major underlying factors driving cooperative breeding in African molerats. By contrast, field and laboratory studies of the eusocial Damaraland mole-rat (Cryptomys damarensis) have raised the possibility that this species is an obligate outbreeder, although the build-up of inbreeding over several generations could still occur. Using microsatellite markers, we show that most breeding pairs in wild colonies of the Damaraland mole-rat are indeed unrelated (R = 0.02 +/- 0.04) and that mean colony relatedness (R = 0.46 +/- 0.01), determined across 15 colonies from three separate populations, is little more than half that previously identified in naked mole-rats. This finding demonstrates that normal familial levels of relatedness are sufficient for the occurrence of eusociality in mammals. Variation in the mean colony relatedness among populations provides support both for the central role played by ecological constraints in cooperative breeding and for the suggestion that inbreeding in naked mole-rats is a response to extreme constraints on dispersal. Approaches that determine the relative importance of an array of extrinsic factors in driving social evolution in African mole-rats are now required.

Animals↗

PubMed1997

Global trends in women's health.

Global trends in women's health have to be looked at in the broader context of the definition of health as a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity. Our species is undergoing a historical bio-social evolution, with women positioned to have more power over their bodies and their lives. The implications for women's health are vast. Our profession has to face new challenges. The woman behind the mother is finally emerging, and making her presence felt. A reproductive evolution is sweeping the globe, with women having to lead a contraceptive life. A contraceptive technology revolution has benefited hundreds of millions, but the task is still unfinished. Demand for quality is substituting a desire for quantity in human reproduction. Sexual health is becoming an important psychosocial component of our health and well-being. The mature adult woman and the elderly woman are rising to an important place in our health care. The widening bio-social gap in adolescents dictates an increasing need for appropriate promotive, preventive and curative health care. One global trend in women's health unfortunately did not happen. Maternity is still, unnecessarily, a major cause of death and morbidity for women in developing countries.

Adult↗

PubMed1998

Boxing, youth and children.

Boxing remains a popular spectator sport, success in which is achieved by the promotion of boxing in the childhood years. Despite the failure to ban boxing generally, there remains the realistic expectation that organised boxing by children below the age of consent (appropriately 16 years) is still achievable. There are two reasons for banning children under the age of 16 years from boxing. The first is that children have little awareness of risk, specifically the risk of chronic encephalopathy, which develops only after a lag period measured in decades or more. The second is that there is no place in contemporary society for a youth sport which has, as its primary goal, the infliction of acute brain damage on an opponent. This paper analyses the medical and ethico-social issues implicit in this subject. Boxing, in historical perspective, has been an altruistic amateur sport for boys and male youths, and has a proud tradition. But in the context of social evolution, and in current perspective to prevent exploitation of underprivileged youths, the time has come for an absolute ban on underage boxing. Such is achievable even if adult boxing remains an Olympic and television sport for some time to come.

Adolescent↗

PubMed1994

Genetics of mutualism: the evolution of altruism between species.

Conditions are analyzed under which natural selection favors an individual to help another species at a cost to its own reproduction. Traditional models for the evolution of altruism between species focus on the genetic relatedness between the original donor and the recipients of return benefits from the mutualistic partner species. A more general model is analyzed here that focuses on the synergistic effects between partner species caused by genetic variability. The model shows that the spread of altruism is enhanced by spatial correlations between species in the genetic tendency to give aid to partners. These spatial correlations between species are similar to the kin selection coefficients of relatedness that determine the course of social evolution within species. The model also shows that natural selection and ecological dynamics can create genetic correlations between neighbors of different species, even when the initial spatial distributions of the species are uncorrelated. Genetic correlations between species may play an important role in the origin and maintenance of altruism between species.

Altruism↗