PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “social evolution”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 1,027 records · Page 57Linked to original sources
PubMed2000

Hylobatid communities: Changing views on pair bonding and social organization in hominoids.

Social organization involving pair bonding and two-adult groups is rare in mammals. Current sociobiological theory suggests that this grouping and behavior pattern is somewhat anomalous. The gibbons (genus Hylobates) are the only hominoids to exhibit pair bonds and two-adult groups. In this article I present an overview of the current issues in monogamy and pair-bond theory, and review traditional conceptualizations and the accumulated data relevant to gibbon social organization. The significance of hominoid behavioral phylogeny and population-wide studies is also considered. Recent findings indicate that pair-bonding and two-adult groups are not ubiquitous among the hylobatids. Many aspects of gibbon behavior and ecology do not conform to expectations of the conditions under which two-adult groups and/or pair-bonding patterns should evolve. A review of the information available from long-term and short-term studies of gibbons suggests an alternative way of viewing their socioecology. I propose that gibbons currently exist in variable communities that have arisen via ecological pressures and specific behavioral patterns from an ancestral multimale/multi-female grouping pattern. This social organization is not best characterized as "monogamous." This review also suggests that hominoid grouping patterns can be viewed as occurring along a continuum rather than as being discretely different units.

Animals↗
PubMed2003

The life and career of Paul MacLean. a journey toward neurobiological and social harmony.

Working as a physician, Paul MacLean's interests moved in the direction of the brain when he realized that most of his patients suffered from symptoms (e.g. anxiety, sleeping problems) that could not be traced to a known physiological cause. His curiosity about the neurological origins of these psychological symptoms led him to the laboratories of Stanley Cobb and James Papez, both of whom were influential in guiding MacLean's interests toward the temporal lobe. His neurobiological interest was not contained, however, to the temporal lobe. As his own family grew to include a wife and five children, his scholarly pursuits extended to social and familial relations and their accompanying underlying neuroanatomical circuits (i.e. the thalamocingulate system). Viewing the brain and behavior from an evolutionary perspective, MacLean introduced the concept of the "triune brain" to describe the evolutionarily distinct components of the mammalian brain and reintroduced Broca's term "limbic" to describe a neuroanatomical system involved in emotional functions. MacLean wrote that the development of social behaviors, such as mother-infant audiovocal communication and the separation cry of the offspring, served as the driving force in the evolution of the neocortex. MacLean's neuroevolutionary perspective and appreciation of the complexity and evolutionary significance of social systems offer valuable insights into the contemporary fields of behavioral neuroscience and biological psychiatry.

History, 20th Century↗
PubMed2001

Evolution of the mental health care system in Poland.

OBJECTIVE: The aim of this paper is to trace evolution of mental health system in Poland. METHOD: Available Polish literature and fundamental policy documents including mental health legislation are reviewed and major milestones in this evolution identified and then discussed against the background of political and social developments. RESULTS: The mental health system evolved since the beginning of the 1970s from large hospitals towards community-based care. It was found that the changes were rather slow due to financial shortages and lack of clear demand from users. Recent transitions offer opportunities to increase impact of users and their families. On the other hand, however, introduction of health insurance system reduces prospects for well co-ordinated mental health policy and may lead to inequalities in access to services. CONCLUSION: It can be concluded that evolution of mental health services has been influenced by prevailing ideologies as much as by technical and professional considerations.

Health Care Reform↗
PubMed2005

Evolutionary, biological origins of morality: implications for research with human embryonic stem cells.

Medical research with human embryonic stem cells, despite its enormous potential to reduce human suffering, is banned in many countries and heavily restricted in others. "Moral reasons" are invoked to justify bans and restrictions on this promising research. Rather surprisingly, while those moral reasons have been extensively discussed and hotly debated in several papers, not a single article on the moral aspects of that research has attempted to answer this fundamental question: What is morality? Considering that a scientifically objective definition of morality is essential to determine whether those moral reasons are justified or groundless, this article focuses on the evolutionary origins of morality and its biological basis. Morality arose as a selectively advantageous product of evolution and preceded all religions and philosophies by millions of years. For the 99% of humankind's evolution, morality was axiomatically aimed at reducing the sufferings of the social members, because pains and afflictions, as expressions of diseases and impairments, tended to hasten the extinction of the small ancestral groups, which characteristically consisted of a few tens of members. Had the therapeutic use of human embryos been available in remote times, our ancestors would have deemed it unquestionably immoral to save amorphous and microscopic agglomerates of insensitive cells representing neither parental nor social investment, at the expense of the lives of the suffering members of their little communities. Unless we venture the untenable thesis that the unlikelihood of extinction of our immense societies entitles us to overturn the meaning of morality, we cannot but conclude that bans and restrictions on research with human embryonic stem cells are patently immoral.

Altruism↗
PubMedDate not supplied

[Anthropologic evolution of women's pelvis].

The existence of dystocia in human presents a vexing problem for an evolutionary point of view. Dealing with the great apes and modern human's pelvis evolution, considering the bipedalism and the cerebral growth, the adaptative mechanisms and their obstetrical and social consequences are discussed.

Adaptation, Physiological↗
PubMed2003

Assessing behavior in extinct animals: was Smilodon social?

It has been suggested that saber-tooth species such as Smilodon fatalis were social because partially healed skeletal injuries were found at Rancho La Brea, California. This conclusion assumes injured animals would die without help. This paper will rebut assertions of sociality. First, cats use metabolic reserves to heal quickly without feeding. Second, dehydration is a more profound limitation than starvation as prey carcasses only provide a quarter of necessary water. Injured animals must be mobile enough to find water or die of dehydration. Their presence in a tar pit also strongly suggests locomotion. Finally, the relatively small brain found in Smilodon is not consistent with sociality. Another argument for sociality has been the large ratio of Smilodon to other species in the La Brea tar pits. However, the remains of a non-social species, the Golden eagle (Aquila chrysaetus), are about as common as Smilodon. Contrariwise, the highly social grey wolf (Canis lupus) and coyote (Canis latrans) are extremely rare. Available evidence does not support sociality in Smilodon.

Animals↗
PubMed2006

A bias for social information in human cultural transmission.

Evolutionary theories concerning the origins of human intelligence suggest that cultural transmission might be biased toward social over non-social information. This was tested by passing social and non-social information along multiple chains of participants. Experiment 1 found that gossip, defined as information about intense third-party social relationships, was transmitted with significantly greater accuracy and in significantly greater quantity than equivalent non-social information concerning individual behaviour or the physical environment. Experiment 2 replicated this finding controlling for narrative coherence, and additionally found that information concerning everyday non-gossip social interactions was transmitted just as well as the intense gossip interactions. It was therefore concluded that human cultural transmission is biased toward information concerning social interactions over equivalent non-social information.

Adult↗
PubMed2006

Valence-sensitive neurons exhibit divergent functional profiles in gregarious and asocial species.

The medial bed nucleus of the stria terminalis (BSTm) influences both social approach and social aversion, suggesting that this structure may play an important role in generating motivational and behavioral differences between gregarious and asocial species. However, no specific neurons have been identified within the BSTm that influence species-typical levels of sociality or that mediate approach and avoidance. Using five songbird species that differ selectively in their species-typical group sizes, we now demonstrate that vasotocin-immunoreactive (VT-ir) neurons of the BSTm exhibit very different immediate early gene responses to same-sex stimuli in gregarious and asocial species. Exposure to a same-sex conspecific increases VT-Fos colocalization in gregarious species while decreasing colocalization in relatively asocial species. We additionally demonstrate that these neurons are selectively activated by social stimuli that normally elicit affiliation (positively valenced social stimuli) but not by stimuli that elicit aversion (negatively valenced social stimuli). Constitutive Fos activity of the VT-ir neurons is also significantly greater in the gregarious species, and the two most social species express significantly more VT-ir neurons. These findings demonstrate that the properties of valence-sensitive neurons evolve in relation to sociality and indicate that gregarious species accentuate positive stimulus properties during social interactions.

Animals↗
PubMed2003

Outline of the evolution of behavioral and nonbehavioral patterns of parental care among the vertebrates: critical characteristics of mammalian and avian parental behavior.

An outline of the evolution of parental care among the vertebrates is presented, leading to a characterization of critical features of parental care among the mammals and birds. Among the lower vertebrates (fishes, amphibia) and reptiles there are a variety of patterns of parental care. These can be divided into those that involve parental behavior and those that are nonbehavioral. Among extant species, parental behavior is not the predominant form of parental care, although it is present in many species of fish, frog and reptile. Nonbehavioral patterns of parental care predominate and are equally effective as parental behavior. Parental behavior is based on reciprocal stimulus interaction (trophallaxis) between the parent and the offspring and includes behavior directed at the nest, eggs, and developing young. Among lower vertebrates and reptiles there are increases in the complexity and completeness of parental behaviors but only among the mammals and birds has parental behavior been elaborated as the only form of parental care. Critical characteristics of mammalian parental behavior are: simultaneous onset of birth, lactation, and maternal care, rapid formation of an attachment of the mother to her offspring, synchrony in the behavioral interaction between mother and young during their development until weaning, and the significance of the mother-offspring unit as the basis of social organization. Among birds there is the period of egg incubation in the nest preceding hatching of the young, in addition to the above characteristics of mammals, but the mother-offspring unit is not the basis for social organization.

Animals↗
PubMed2001

Why people punish defectors. Weak conformist transmission can stabilize costly enforcement of norms in cooperative dilemmas.

In this paper, we present a cultural evolutionary model in which norms for cooperation and punishment are acquired via two cognitive mechanisms: (1) payoff-biased transmission-a tendency to copy the most successful individual; and (2) conformist transmission-a tendency to copy the most frequent behavior in the population. We first show that if a finite number of punishment stages is permitted (e.g. two stages of punishment occur if some individuals punish people who fail to punish non-cooperators), then an arbitrarily small amount of conformist transmission will stabilize cooperative behavior by stabilizing punishment at some n -th stage. We then explain how, once cooperation is stabilized in one group, it may spread through a multi-group population via cultural group selection. Finally, once cooperation is prevalent, we show how prosocial genes favoring cooperation and punishment may invade in the wake of cultural group selection.

Cooperative Behavior↗
PubMed1989

Non-governmental organizations in the health field: collaboration, integration and contrasting aims.

Non-governmental organizations, from being voluntary agencies often with relief or religious mission orientations, have become very important players in the field of social development. In this paper something is given of their evolution, diversity, aims and activities; and of the important role they now play in many instances, as well as some of the obstacles to collaboration, co-ordination and integration at different levels of operation--internationally, nationally and locally.

Financing, Government↗
PubMed2004

Evolutionary origins of depression: a review and reformulation.

There has been a recent surge of interest in the evolutionary basis of depression. One approach argues that the affective mechanisms that are dysregulated in depression are adaptations, whilst a second approach argues that depression itself is an adaptation. The evidence relating to whether depression could itself be an adaptation is reviewed. Adaptations generally have four hallmarks; they lack heritable variation, show evidence of good design, are evoked by appropriate triggers, and fitness is reduced where they are absent. Depression shows none of these hallmarks. It is characterized by heritability, recurrence, cognitive impairment, and poor social outcome. In an alternative evolutionary formulation, I argue that evolution has produced a continuous population distribution of affective reactivity that is subject to stabilizing selection. Individuals vulnerable to depression are at the upper end of this distribution. This conceptualization, in which depression itself is not selected for, is compatible with the known clinical and epidemiological facts.

Adaptation, Psychological↗
PubMed2004

Reactive strategies in indirect reciprocity.

Evolution of reactive strategy of indirect reciprocity is discussed, where individuals interact with others through the one-shot Prisoner's Dilemma game, changing their partners in every round. We investigate all of the reactive strategies that are stochastic, including deterministic ones as special cases. First we study adaptive dynamics of reactive strategies by assuming monomorphic population. Results are very similar to the corresponding evolutionary dynamics of direct reciprocity. The discriminating strategy, which prescribes cooperation only with those who cooperated in the previous round, cannot be an outcome of the evolution. Next we examine the case where the population includes a diversity of strategies. We find that only the mean 'discriminatoriness' in the population is the parameter that affects the evolutionary dynamics. The discriminating strategy works as a promoter of cooperation there. However, it is again not the end point of the evolution. This is because retaliatory defection, which was prescribed by the discriminating strategy, is regarded as another defection toward the society. These results caution that we have to reconsider the role of retaliatory defection much more carefully.

Altruism↗
PubMed2004

The cognitive foundations of cultural stability and diversity.

The existence and diversity of human cultures are made possible by our species-specific cognitive capacities. But how? Do cultures emerge and diverge as a result of the deployment, over generations and in different populations, of general abilities to learn, imitate and communicate? What role if any do domain-specific evolved cognitive abilities play in the emergence and evolution of cultures? These questions have been approached from different vantage points in different disciplines. Here we present a view that is currently developing out of the converging work of developmental psychologists, evolutionary psychologists and cognitive anthropologists.

Cognition↗