Cooperation in organisms, whether bacteria or primates, has been a difficulty for evolutionary theory since Darwin. On the assumption that interactions between pairs of individuals occur on a probabilistic basis, a model is developed based on the concept of an evolutionarily stable strategy in the context of the Prisoner's Dilemma game. Deductions from the model, and the results of a computer tournament show how cooperation based on reciprocity can get started in an asocial world, can thrive while interacting with a wide range of other strategies, and can resist invasion once fully established. Potential applications include specific aspects of territoriality, mating, and disease.

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The Evolution of Cooperation

Our possessions are a major contributor to and reflection of our identities A variety of evidence is presented supporting this simple and compelling premise Related streams of research are identified and drawn upon in developing this concept and implications are derived for consumer behavior Because the construct of extended self involves consumer behavior rather than buyer behavior, it appears to be a much richer construct than previous formulations positing a relationship between self-concept and consumer brand choice

https://www.jstor.org/stable/pdfplus/2489522.pdf

Possessions and the extended self.

In this chapter a theory of motivation and emotion developed from an attributional perspective is presented Before undertaking this central task, it might be beneficial to review the progression of the book In Chapter 1 it was suggested that causal attributions have been prevalent throughout history and in disparate cultures Studies reviewed in Chapter 2 revealed a large number of causal ascriptions within motivational domains, and different ascriptions in disparate domains Yet some attributions, particularly ability and effort in the achievement area, dominate causal thinking To compare and contrast causes such as ability and effort, their common denominators or shared properties were identified Three causal dimensions, examined in Chapter 3, are locus, stability, and controllability, with intentionality and globality as other possible causal properties As documented in Chapter 4, the perceived stability of a cause influences the subjective probability of success following a previous success or failure; causes perceived as enduring increase the certainty that the prior outcome will be repeated in the future And all the causal dimensions, as well as the outcome of an activity and specific causes, influence the emotions experienced after attainment or nonattainment of a goal The affects linked to causal dimensions include pride (with locus), hopelessness and resignation (with stability), and anger, gratitude, guilt, pity, and shame (with controllability)

/pdf/an-attributional-theory-of-achievement-motivation-and-2eu5g13rxj.pdf

An attributional theory of achievement motivation and emotion.

Research on moral judgment has been dominated by rationalist models, in which moral judgment is thought to be caused by moral reasoning. The author gives 4 reasons for considering the hypothesis that moral reasoning does not cause moral judgment; rather, moral reasoning is usually a post hoc construction, generated after a judgment has been reached. The social intuitionist model is presented as an alternative to rationalist models. The model is a social model in that it deemphasizes the private reasoning done by individuals and emphasizes instead the importance of social and cultural influences. The model is an intuitionist model in that it states that moral judgment is generally the result of quick, automatic evaluations (intuitions). The model is more consistent than rationalist models with recent findings in social, cultural, evolutionary, and biological psychology, as well as in anthropology and primatology.

https://www.motherjones.com/files/emotional_dog_and_rational_tail.pdf

The emotional dog and its rational tail: a social intuitionist approach to moral judgment.

There is a tendency among biologists studying social behavior to regard the adult sex ratio as an independent variable to which the species reacts with appropriate adaptations D Lack often interprets social behavior as an adaptation in part to an unbalanced (or balanced) sex ratio, and J Verner has summarized other instances of this tendency The only mechanism that will generate differential mortality independent of sexual differences clearly related to parental investment and sexual selection is the chromosomal mechanism, applied especially to humans and other mammals: the unguarded X chromosome of the male is presumed to predispose him to higher mortality Each offspring can be viewed as an investment independent of other offspring, increasing investment in one offspring tending to decrease investment in others Species can be classified according to the relative parental investment of the sexes in their young In the vast majority of species, the male's only contribution to the survival of his offspring is his sex cells

Parental investment and sexual selection

A model is presented to account for the natural selection of what is termed reciprocally altruistic behavior. The model shows how selection can operate against the cheater (non-reciprocator) in the system. Three instances of altruistic behavior are discussed, the evolution of which the model can explain: (1) behavior involved in cleaning symbioses; (2) warning cries in birds; and (3) human reciprocal altruism. Regarding human reciprocal altruism, it is shown that the details of the psychological system that regulates this altruism can be explained by the model. Specifically, friendship, dislike, moralistic aggression, gratitude, sympathy, trust, suspicion, trustworthiness, aspects of guilt, and some forms of dishonesty and hypocrisy can be explained as important adaptations to regulate the altruistic system. Each individual human is seen as possessing altruistic and cheating tendencies, the expression of which is sensitive to developmental variables that were selected to set the tendencies at a balance ap...

/pdf/the-evolution-of-reciprocal-altruism-36v5rn897k.pdf

The Evolution of Reciprocal Altruism

Theory and data suggest that a male in good condition at the end of the period of parental investment is expected to outreproduce a sister in similar condition, while she is expected to outreproduce him if both are in poor condition. Accordingly, natural selection should favor parental ability to adjust the sex ratio of offspring produced according to parental ability to invest. Data from mammals support the model: As maternal condition declines, the adult female tends to produce a lower ratio of males to females.

https://science.sciencemag.org/content/sci/179/4068/90.full.pdf

Natural selection of parental ability to vary the sex ratio of offspring.

When parent-offspring relations in sexually reproducing species are viewed from the standpoint of the offspring as well as the parent, conflict is seen to be an expected feature of such relations. In particular, parent and offspring are expected to disagree over how long the period of parental investment should last, over the amount of parental investment that should be given, and over the altruistic and egoistic tendencies of the offspring as these tendencies affect other relatives. In addition, under certain conditions parents and offspring are expected to disagree over the preferred sex of the potential offspring. In general, parent-offspring conflict is expected to increase during the period of parental care, and offspring are expected to employ psychological weapons in order to compete with their parents. Detailed data on mother-offspring relations in mammals are consistent with the arguments presented. Conflict in some species, including the human species, is expected to extend to the adult reproductive role of the offspring: under certain conditions parents are expected to attempt to mold an offspring, against its better interests, into a permanent nonreproductive.

/pdf/parent-offspring-conflict-40puvk2doc.pdf

Parent-Offspring Conflict

Halminton (1) was apparently the first to appreciate that the synthesis of Mendelian genetics with Darwin's theory of natural selection had profound implications for social theory. In particular, insofar as almost all social behavior is either selfish or altruistic (or has such effects), genetical reasoning suggests that an individual's social behavior should be adjusted to his or her degree of relatedness, r, to all individuals affected by the behavior. We call this theory kinship theory. The social insects provide a critical test of Hamilton's kinship theory. When such theory is combined with the sex ratio theory of Fisher (9), a body of consistent predictions emerges regarding the haplodiploid Hymenoptera. The evolution of female workers helping their mother reproduce is more likely in the Hymenoptera than in diploid groups, provided that such workers lay some of the male-producing eggs or bias the ratio of investment toward reproductive females. Once eusocial colonies appear, certain biases by sex in these colonies are expected to evolve. In general, but especially in eusocial ants, the ratio of investment should be biased in favor of females, and in it is expected to equilibrate at 1 : 3 (male to female). We present evidence from 20 species that the ratio of investment in monogynous ants is, indeed, about 1 : 3, and we subject this discovery to a series of tests. As expected, the slave-making ants produce a ratio of investment of 1 : 1, polygynoys ants produce many more males than expected on the basis of relative dry weight alone, solitary bees and wasps produce a ratio of investment near 1 : 1 (and no greater than 1 : 2), and the social bumblebees produce ratios of investment between 1 : 1 and 1 : 3. In addition, sex ratios in monogynous ants and in trapnested wasps are, as predicted by Fisher, inversely related to the relative cost in these species of producing a male instead of a female. Taken together, these data provide quantitative evidence in support of kinship theory, sex ratio theory, the assumption that the offspring is capable of acting counter to its parents' best interests, and the supposition that haplodiploidy has played a unique role in the evolution of the social insects. Finally, we outline a theory for the evolution of worker-queen conflict, a theory which explains the queen's advantage in competition over male-producing workers and the workers' advantage regarding the ratio of investment. The theory uses the asymmetries of haplodiploidy to explain how the evolved outcome of parent-offspring conflict in the social Hymenoptera is expected to be a function of certain social and life history parameters.

https://science.sciencemag.org/content/sci/191/4224/249.full.pdf

Robert Trivers

Papers

Parental investment and sexual selection

The Evolution of Reciprocal Altruism

Natural selection of parental ability to vary the sex ratio of offspring.

Parent-Offspring Conflict

Haploidploidy and the evolution of the social insect