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At least 433 records · Page 24Linked to original sources
PubMed2001

The polyvagal theory: phylogenetic substrates of a social nervous system.

The evolution of the autonomic nervous system provides an organizing principle to interpret the adaptive significance of physiological responses in promoting social behavior. According to the polyvagal theory, the well-documented phylogenetic shift in neural regulation of the autonomic nervous system passes through three global stages, each with an associated behavioral strategy. The first stage is characterized by a primitive unmyelinated visceral vagus that fosters digestion and responds to threat by depressing metabolic activity. Behaviorally, the first stage is associated with immobilization behaviors. The second stage is characterized by the sympathetic nervous system that is capable of increasing metabolic output and inhibiting the visceral vagus to foster mobilization behaviors necessary for 'fight or flight'. The third stage, unique to mammals, is characterized by a myelinated vagus that can rapidly regulate cardiac output to foster engagement and disengagement with the environment. The mammalian vagus is neuroanatomically linked to the cranial nerves that regulate social engagement via facial expression and vocalization. As the autonomic nervous system changed through the process of evolution, so did the interplay between the autonomic nervous system and the other physiological systems that respond to stress, including the cortex, the hypothalamic-pituitary-adrenal axis, the neuropeptides of oxytocin and vasopressin, and the immune system. From this phylogenetic orientation, the polyvagal theory proposes a biological basis for social behavior and an intervention strategy to enhance positive social behavior.

Animals↗
PubMed1995

Mutual policing and repression of competition in the evolution of cooperative groups.

Evolutionary theory has not explained how competition among lower level units is suppressed in the formation of higher-level evolutionary units. For example, the key problem of early evolution is small, individual replicators formed cooperative groups of sufficient complexity to allow accurate copying of the genetic material. The puzzle is why parasites did not subvert the formation of cells by obtaining benefits from the group without contributing to shared traits that enhance reproduction. These parasites would outcompete other replicators within the cell, disrupting reproductive fairness among subunits and destroying the functional coherence of the group. A similar problem arose at a later evolutionary stage with the orderly mendelian segregation of subunits (chromosomes) within cells, and reproductive fairness continued to be a problem in the evolution of insect and human societies. Here I present a simple model to show how reproductive fairness evolves among subunits to create functional coherence and higher-level units. Self-restraint, which evolves according to the kin-selection coefficient of relatedness, is not sufficient: mutual policing and enforcement of reproductive fairness are also required for the evolution of increasing social complexity.

Biological Evolution↗
PubMed2003

Social neuroscience, empathy, brain integration, and neurodevelopmental disorders.

Paul MacLean has investigated integrated brain functioning through selected brain lesions in animals that disturb circuits necessary for complex behaviors, such as social displays. MacLean is unique in his comparative neurobehavioral approach that emphasizes the evolutionary origins of parenting and social behaviors and the implications of brain changes in the evolution from reptiles (social displays) to mammals (nursing, audiovocal communication, play) to man (self-awareness, intentionality, social context) that link affect and cognition. Subjectively, how "looking with feeling toward others," the basic element in empathy, evolved has been a central concern of his. Neuroimaging studies of social cognition, mother-infant communication, moral behavior, forgiveness, and trust are consistent with particular brain systems being activated in cooperative social behaviors. The identification of mirror neurons is pertinent to MacLean's model of isopraxis and studies of thalamocortical resonances may be pertinent to his neurobehavioral models. Studies of behavioral phenotypes in human neurodevelopmental disorders are consistent with MacLean's model of brain circuits being linked to complex behaviors during development. In autistic disorder, the behavioral phenotype involves disrupted social communication, deviant imaginative play, and motor stereotypies. In Lesch-Nyhan syndrome (LNS), self-injury occurs in individuals with normal sensory systems intact who require and request physical restraint to prevent self-injury; they ask for assistance from others to prevent them from harming themselves. Autism involves the lack of subjective awareness of others intentions and LNS involves a failure in self-regulation and self-control of self-injurious behavior. MacLean's models laid the groundwork for studies focused on understanding brain functioning in these conditions.

Animals↗
PubMed2006

Evolution of the Yellow/Major Royal Jelly Protein family and the emergence of social behavior in honey bees.

The genomic architecture underlying the evolution of insect social behavior is largely a mystery. Eusociality, defined by overlapping generations, parental brood care, and reproductive division of labor, has most commonly evolved in the Hymenopteran insects, including the honey bee Apis mellifera. In this species, the Major Royal Jelly Protein (MRJP) family is required for all major aspects of eusocial behavior. Here, using data obtained from the A. mellifera genome sequencing project, we demonstrate that the MRJP family is encoded by nine genes arranged in an approximately 60-kb tandem array. Furthermore, the MRJP protein family appears to have evolved from a single progenitor gene that encodes a member of the ancient Yellow protein family. Five genes encoding Yellow-family proteins flank the genomic region containing the genes encoding MRJPs. We describe the molecular evolution of these protein families. We then characterize developmental-stage-specific, sex-specific, and caste-specific expression patterns of the mrjp and yellow genes in the honey bee. We review empirical evidence concerning the functions of Yellow proteins in fruit flies and social ants, in order to shed light on the roles of both Yellow and MRJP proteins in A. mellifera. In total, the available evidence suggests that Yellows and MRJPs are multifunctional proteins with diverse, context-dependent physiological and developmental roles. However, many members of the Yellow/MRJP family act as facilitators of reproductive maturation. Finally, it appears that MRJP protein subfamily evolution from the Yellow protein family may have coincided with the evolution of honey bee eusociality.

Animals↗
PubMed2002

Docile sitters and active fighters in paper wasps: a tale of two queens.

Ropalidia marginata and Ropalidia cyathiformis are sympatric, primitively eusocial paper wasps widely distributed in peninsular India. We compare the two species, especially their queens, in an attempt to begin to understand the role of the power of queens over their workers, in social organisation and evolution. Queens of R. marginata have lower levels of activity, rates of interactions and dominance behaviour, compared with queens of R. cyathiformis. For the same variables, R. marginata queens are either indistinguishable from or have lower values than their workers, while R. cyathiformis queens have higher values than their workers. R. marginata queens never occupy the top rank while R. cyathiformis queens are always at the top of the behavioural dominance hierarchies of their colonies. R. marginata queens thus do not appear to use dominance behaviour to suppress reproduction by their workers, while R. cyathiformis queens appear to do so. These different mechanisms used by the two queens to regulate worker reproduction give them different powers over their workers, because R. marginata queens are completely successful in suppressing reproduction by their nestmates while in R. cyathiformis colonies, other individuals also sometimes lay eggs. There is also some evidence that the different powers of the queens result in different mechanisms of regulation of worker foraging in the two species--decentralised, self-regulation in R. marginata and relatively more centralised regulation by the queen in R. cyathiformis. Thus we show here, perhaps for the first time, that the power of the queens over their workers can have important consequences for social organisation and evolution.

Aggression↗
PubMed2001

Sexual conflict and the evolution of female mate choice and male social dominance.

Conflicts between the sexes over control of reproduction are thought to lead to a cost of sexual selection through the evolution of male traits that manipulate female reproductive physiology and behaviour, and female traits that resist this manipulation. Although studies have begun to document negative fitness effects of sexual conflict, studies showing the expected association between sexual conflict and the specific behavioural mechanisms of sexual selection are lacking. Here we experimentally manipulated the opportunity for sexual conflict in the cockroach. Nauphoeta cinerea and showed that, for this species, odour cues in the social environment influence the behavioural strategies and fitness of males and females during sexual selection. Females provided with the opportunity for discriminating between males but not necessarily mating with preferred males produced fewer male offspring than females mated at random. The number of female offspring produced was not affected, nor was the viability of the offspring. Experimental modification of the composition of the males' pheromone showed that the fecundity effects were caused by exposure to the pheromone component that makes males attractive to females but also makes males less likely to be dominant. Female mate choice therefore carries a demographic cost but functions to avoid male manipulation and aggression. Male-male competition appears to function to circumvent mate choice rather than directly manipulating females, as the mate choice can be cryptic. The dynamic struggle between the sexes for control of mating opportunities and outcomes in N. cinerea therefore reveals a unique role for sexual conflict in the evolution of the behavioural components of sexual selection.

Animals↗
PubMed2003

Food competition in captive female sooty mangabeys (Cercocebus torquatus atys).

We studied the social and foraging behavior of two captive groups of sooty mangabeys under two different spatial food situations. These food conditions were clumped (food was placed in a box) and dispersed (food was dispersed over the entire enclosure). In each group five adult females and two adult males were observed. As a criterion for food competition, individual differences in the relative food intake were used. Adult female mangabeys had a linear, stable, and unidirectional dominance hierarchy. Access to food was rank dependent among females only under clumped food distribution, as current models of the evolution of primate social systems predict. However, feeding success appeared to be mediated not by female but by male agonistic behavior toward females. High-ranking females received relatively less aggression from males and could, therefore, stay and feed longer in the feeding area. Male tolerance of higher-ranking females seems to mediate female feeding success under restricted food resources. The establishment of a special relationship with a high-ranking male might, therefore, be a strategy to get better access to food. This study demonstrates that female competition for access to food should not be analyzed separately from male influences on females and suggests that a more integral role of males in socioecological models of the evolution of primate social systems should be considered.

Animals↗
PubMed2005

Human-like social skills in dogs?

Domestic dogs are unusually skilled at reading human social and communicative behavior--even more so than our nearest primate relatives. For example, they use human social and communicative behavior (e.g. a pointing gesture) to find hidden food, and they know what the human can and cannot see in various situations. Recent comparisons between canid species suggest that these unusual social skills have a heritable component and initially evolved during domestication as a result of selection on systems mediating fear and aggression towards humans. Differences in chimpanzee and human temperament suggest that a similar process may have been an important catalyst leading to the evolution of unusual social skills in our own species. The study of convergent evolution provides an exciting opportunity to gain further insights into the evolutionary processes leading to human-like forms of cooperation and communication.

Animal Communication↗
PubMed2004

Some neurological aspects of laughter.

This brief survey of laughter attempts an analysis of its neurological mechanisms, evolution, role in social behaviour and its clinicopathological importance. The mechanisms of laughter, its physiological consequences and its demonstration by sound spectrography are considered. Something resembling laughter occurs in certain primates, and possibly rodents, though there are important differences. The evolution of laughter in a social context is appraised. Pathological laughter arises rarely, usually caused by diseases of the frontal or temporal lobes, and in hypothalamic hamartomata in children.

Animals↗
PubMed1977

Attitudes toward social work in family medicine: a before and after survey.

An initial survey of attitudes among Family Medical Center staff rated social work as highly consistent with the values of family medicine, capable of competently addressing difficult problems, and contributing valuably to a team approach to continuous and comprehensive family medical care. After integration of a social worker into the practice, a repeat survey documented significant attitude changes, rating social work as more competent, passive, and difficult, and lowering the estimate of patients potentially helped by a social worker from 38 percent to 31 percent. Such attitudes may influence the evolution of the social worker's role in the family medicine patient care team.

Attitude of Health Personnel↗
PubMed2006

The folk psychology of souls.

The present article examines how people's belief in an afterlife, as well as closely related supernatural beliefs, may open an empirical backdoor to our understanding of the evolution of human social cognition. Recent findings and logic from the cognitive sciences contribute to a novel theory of existential psychology, one that is grounded in the tenets of Darwinian natural selection. Many of the predominant questions of existential psychology strike at the heart of cognitive science. They involve: causal attribution (why is mortal behavior represented as being causally related to one's afterlife? how are dead agents envisaged as communicating messages to the living?), moral judgment (why are certain social behaviors, i.e., transgressions, believed to have ultimate repercussions after death or to reap the punishment of disgruntled ancestors?), theory of mind (how can we know what it is "like" to be dead? what social-cognitive strategies do people use to reason about the minds of the dead?), concept acquisition (how does a common-sense dualism interact with a formalized socio-religious indoctrination in childhood? how are supernatural properties of the dead conceptualized by young minds?), and teleological reasoning (why do people so often see their lives as being designed for a purpose that must be accomplished before they perish? how do various life events affect people's interpretation of this purpose?), among others. The central thesis of the present article is that an organized cognitive "system" dedicated to forming illusory representations of (1) psychological immortality, (2) the intelligent design of the self, and (3) the symbolic meaning of natural events evolved in response to the unique selective pressures of the human social environment.

Attitude to Death↗
PubMed2006

Reliance on head versus eyes in the gaze following of great apes and human infants: the cooperative eye hypothesis.

As compared with other primates, humans have especially visible eyes (e.g., white sclera). One hypothesis is that this feature of human eyes evolved to make it easier for conspecifics to follow an individual's gaze direction in close-range joint attentional and communicative interactions, which would seem to imply especially cooperative (mututalistic) conspecifics. In the current study, we tested one aspect of this cooperative eye hypothesis by comparing the gaze following behavior of great apes to that of human infants. A human experimenter "looked" to the ceiling either with his eyes only, head only (eyes closed), both head and eyes, or neither. Great apes followed gaze to the ceiling based mainly on the human's head direction (although eye direction played some role as well). In contrast, human infants relied almost exclusively on eye direction in these same situations. These results demonstrate that humans are especially reliant on eyes in gaze following situations, and thus, suggest that eyes evolved a new social function in human evolution, most likely to support cooperative (mututalistic) social interactions.

Animals↗
PubMed1996

Child maltreatment: testing the social isolation hypothesis.

Several barriers limit our attempts to untangle the social context of child maltreatment. One major barrier is our inability to agree on or effectively communicate what social isolation is. In an attempt to clarify this construct, the introductory section traces the evolution of the social isolation construct over the last three decades and concludes it is not one etiologic factor for child maltreatment, but rather, a large set of variables linked to the parent's perception of support, and their informal and formal networks. The empirical section examines each component of the social isolation construct by comparing 300 maltreating and nonmaltreating low-income mothers. Considerable variation is found between the networks of different types of maltreating mothers and nonmaltreating mothers on structural network properties, perception of support, and the types of resources they do and do not receive. For example, neglectful mothers had fewer network members, fewer contacts, fewer members living within 1 hour, and received fewer emotional and instrumental resources. Despite these findings, the label "social isolation" may not accurately describe the networks of mothers who maltreat their children, since all three types of maltreaters had at least eight important network members and more than 100 contacts with these members in the month before completing the questionnaire.

Adult↗
PubMed2005

The social nature of primate cognition.

The hypothesis that the enlarged brain size of the primates was selected for by social, rather than purely ecological, factors has been strongly influential in studies of primate cognition and behaviour over the past two decades. However, the Machiavellian intelligence hypothesis, also known as the social brain hypothesis, tends to emphasize certain traits and behaviours, like exploitation and deception, at the expense of others, such as tolerance and behavioural coordination, and therefore presents only one view of how social life may shape cognition. This review outlines work from other relevant disciplines, including evolutionary economics, cognitive science and neurophysiology, to illustrate how these can be used to build a more general theoretical framework, incorporating notions of embodied and distributed cognition, in which to situate questions concerning the evolution of primate social cognition.

Animals↗