I argue that images of the notion of group, in correspondence with their social and political values, shape the debate over the evolution of altruism by group selection. Important aspects of this debate are empirical, and criteria can decide among a variety of selection processes. However, leading researchers undermine or reinterpret such tests, explaining the evolution of altruism on the basis of a single extreme metaphor of ‘group’ and a single inclusive selection process. I shall argue that the extreme images (...) for the notion of group are associated with ideologies that these researchers support or fear. Hence, the history of social and political uses of ‘group’ and ‘group selection’ can explain, at least in part, some of the empirical deficiencies of the debate, and why it has continued without resolution or dissolution. (shrink)

A proper function of an entity is a beneficial effect that helps explain the persistence of the entity. Proper functions thereby arise through feedback mechanisms with beneficial effects as inputs and persistence as outputs. We continue to make assertions because they benefit speakers by benefiting speakers. Hearers benefit from true information. Speakers benefit by influencing hearer belief. If hearers do not benefit, they will not form beliefs in response to assertions. Speakers can then only maintain influence by providing true information, (...) often enough. The function of assertion is then inducing true hearer belief. When interests conflict, however, some mechanism must ensure that speakers provide true information often enough, instead of deceiving, or providing information regardless of quality. In humans, a core mechanism stabilizing true assertion involves social norms for truth telling. We tell the truth partly because we prescribe and enforce telling the truth. (shrink)

Human societies are extraordinarily cooperative compared to those of most other animals. In the vast majority of species, individuals live solitary lives, meeting to only to mate and, sometimes, raise their young. In social species, cooperation is limited to relatives and (maybe) small groups of reciprocators. After a brief period of maternal support, individuals acquire virtually all of the food that they eat. There is little division of labor, no trade, and no large scale conflict. Communication is limited to a (...) small repertoire of self-verifying signals. No one cares for the sick, or feeds the hungry or disabled. The strong take from the weak without fear of sanctions by third parties. Amend Hobbes to account for nepotism, and his picture of the state of nature is not so far off for most other animals. In contrast, people in even the simplest human societies regularly cooperate with many unrelated individuals. Human language allows low-cost honest communication of virtually unlimited complexity. The sick are cared for, and sharing leads to substantial flows of food from the middle aged to the young and old. Division of labor and trade are prominent features of every historically known human society, and archaeology indicates that they have a long history. Violent conflict among sizable groups is common. In every human society, social life is regulated by commonly held moral systems that specify the rights and duties of individuals enforced, albeit imperfectly, by third party sanctions. (shrink)

Group selection is increasingly being viewed as an important force in human evolution. This paper examines the views of R.D. Alexander, one of the most influential thinkers about human behavior from an evolutionary perspective, on the subject of group selection. Alexander's general conception of evolution is based on the gene-centered approach of G.C. Williams, but he has also emphasized a potential role for group selection in the evolution of individual genomes and in human evolution. Alexander's views are internally inconsistent and (...) underestimate the importance of group selection. Specific themes that Alexander has developed in his account of human evolution are important but are best understood within the framework of multilevel selection theory. From this perspective, Alexander's views on moral systems are not the radical departure from conventional views that he claims, but remain radical in another way more compatible with conventional views. (shrink)

In recent years, much has been learned about the strategic and organizational contexts of suicide attacks. However, motivations of the agents who commit them remain difficult to explain. In part this is because standard models of social learning as well as Durkheimian notions of sacrificial behavior are inadequate in the face of the actions of human bombers. In addition, the importance of organizational structures and practices in reinforcing commitment on the part of suicide recruits is an under-explored factor in many (...) analyses. This essay examines the potential applicability of evolutionary models of altruism to the understanding of commitment to suicide on the part of terrorist organizational recruits. Three evolutionary models of sacrificial behavior in nonhuman species and many categories of human behavior are explored cross-organizationally: reciprocity, inclusive fitness theory, and induced altruism. Reciprocal altruism is unlikely to be a major motivator in suicide attacks because the costs exhibited by attackers are too high to be adequately compensated. However, the role of evolved self-deception in perceptions of personal death, and thus of rewards in the afterlife, is potentially illuminating. Inclusive fitness theory can help explain the motivations of attackers because rewards to kin often are offered by organizations to suicide recruits. However, suicide bombers also often act out of revenge for the loss of or injury to relatives, and inclusive fitness theory generally, as well as more specific theoretical models of retaliatory aggression, may not adequately account for the bombers' actions. Predictions from induced altruism theory appear to be well supported because suicide terror organizations tend to be tightly structured around practices intended to maintain and reinforce commitment though the manipulation of kinship-recognition cues. (shrink)

Human societies are examined as distinct and coherent groups. This trait is most parsimoniously considered a deeply rooted part of our ancestry rather than a recent cultural invention. Our species is the only vertebrate with society memberships of significantly more than 200. We accomplish this by using society-specific labels to identify members, in what I call an anonymous society. I propose that the human brain has evolved to permit not only the close relationships described by the social brain hypothesis, but (...) also, at little mental cost, the anonymous societies within which such alliances are built. The human compulsion to discover or invent labels to “mark” group memberships may originally have been expressed in hominins as vocally learned greetings only slightly different in function from chimpanzee pant hoots (now known to be society-specific). The weight of evidence suggests that at some point, conceivably early in the hominin line, the distinct groups composed of several bands that were typical of our ancestors came to be distinguished by their members on the basis of multiple labels that were socially acquired in this way, the earliest of which would leave no trace in the archaeological record. Often overlooked as research subjects, these sizable fission-fusion communities, in recent egalitarian hunter-gatherers sometimes 2,000 strong, should consistently be accorded the status of societies, in the same sense that this word is used to describe tribes, chiefdoms, and other cultures arising later in our history. The capacity of hunter-gatherer societies to grow sufficiently populous that not all members necessarily recognize one another would make the transition to larger agricultural societies straightforward. Humans differ from chimpanzees in that societal labels are essential to the maintenance of societies and the processes giving birth to new ones. I propose that anonymous societies of all kinds can expand only so far as their labels can remain sufficiently stable. (shrink)

Why do we have social norms—of fairness, cooperation, trust, property, or gender? Modern-day Humeans, as I call them, believe these norms are best accounted for in cultural evolutionary terms, as adaptive solutions to recurrent problems of social interaction. In this paper, I discuss a challenge to this “Humean Program.” Social norms involve widespread behaviors, but also distinctive psychological attitudes and dispositions. According to the challenge, Humean accounts of norms leave their psychological side unexplained. They explain, say, why we share equally, (...) but not why we disapprove of those who don’t. I defend the Humean Program against this challenge. In particular, I suggest an idea for how to extend the Program to account for the psychological side of norms. Socially adaptive behaviors aren’t just likely to emerge in a group; They are also likely to be widely taught within it. The transmission of these behaviors through instruction explains why they are associated with distinctive normative attitudes and dispositions. These attitudes play a pedagogical role in helping transmit these behaviors to children and newcomers. (shrink)

Research in various disciplines has highlighted that humans are uniquely able to solve the problem of cooperation through the informal mechanisms of reputation and gossip. Reputation coordinates the evaluative judgments of individuals about one another. Direct observation of actions and communication are the essential routes that are used to establish and update reputations. In large groups, where opportunities for direct observation are limited, gossip becomes an important channel to share individual perceptions and evaluations of others that can be used to (...) condition cooperative action. Although reputation and gossip might consequently support large-scale human cooperation, four puzzles need to be resolved to understand the operation of reputation-based mechanisms. First, we need empirical evidence of the processes and content that form reputations and how this may vary cross-culturally. Second, we lack an understanding of how reputation is determined from the muddle of imperfect, biased inputs people receive. Third, coordination between individuals is only possible if reputation sharing and signaling is to a large extent reliable and valid. Communication, however, is not necessarily honest and reliable, so theoretical and empirical work is needed to understand how gossip and reputation can effectively promote cooperation despite the circulation of dishonest gossip. Fourth, reputation is not constructed in a social vacuum; hence we need a better understanding of the way in which the structure of interactions affects the efficiency of gossip for establishing reputations and fostering cooperation. (shrink)

The chapter explains why evolutionary genetics – a mathematical body of theory developed since the 1910s – eventually got to deal with culture: the frequency dynamics of genes like “the lactase gene” in populations cannot be correctly modeled without including social transmission. While the body of theory requires specific justifications, for example meticulous legitimations of describing culture in terms of traits, the body of theory is an immensely valuable scientific instrument, not only for its modeling power but also for the (...) amount of work that has been necessary to build, maintain, and expand it. A brief history of evolutionary genetics is told to demonstrate such patrimony, and to emphasize the importance and accumulation of statistical knowledge therein. The probabilistic nature of genotypes, phenogenotypes and population phenomena is also touched upon. Although evolutionary genetics is actually composed by distinct and partially independent traditions, the most important mathematical object of evolutionary genetics is the Mendelian space, and evolutionary genetics is mostly the daring study of trajectories of alleles in a population that explores that space. The ‘body’ is scientific wealth that can be invested in studying every situation that happens to turn out suitable to be modeled as a Mendelian population, or as a modified Mendelian population, or as a population of continuously varying individuals with an underlying Mendelian basis. Mathematical tinkering and justification are two halves of the mutual adjustment between the body of theory and the new domain of culture. Some works in current literature overstate justification, misrepresenting the relationship between body of theory and domain, and hindering interdisciplinary dialogue. (shrink)

Version 3.0 12/02/00. Submitted to R.M. Nesse The Evolution of Subjective Commitment, Russell Sage Foundation. Please do not cite without author’s permission.  by Peter J. Richerson and Robert Boyd. Comments welcome! Word count 14,487.

Is society an organic whole with each of its many components working together like the organs in a body? Like organisms, societies are composed of many parts which seem to work together enhance their survival. Different people fulfill different, necessary role—subsistence, reproduction, coordination, and defense. Regular exchange of matter and energy guarantees that each component has the resources it needs. Norms, laws and customs regulate virtually every aspect of social interaction, who may marry who, how disputes are resolved, and how (...) verbs should be conjugated. Ritual and religion provide comfort to the sick and fearful, maintain a feeling of solidarity and belonging, and serve to preserve and transmit knowledge through time. Even the simplest human societies seem like complex machines designed for growth and survival. (shrink)

E.O. Wilson (1975) described humans as one of the four pinnacles of social evolution. The other pinnacles are the colonial invertebrates, the social insects, and the non-human mammals. Wilson separated human sociality from that of the rest of the mammals because, with the exception of the social insect like Naked Mole Rats, only humans have generated societies of a grade of complexity that approaches that of the social insects and colonial invertebrates. In the last few millennia, human societies have even (...) begun to exceed, in numbers of individuals and degree of complexity, the societies of ants, termites, and corals. (shrink)