Chapter 14

• Sociality


  Tendency to associate with members of the same species
• Sociality


  • Importance in human life and psychology
  • Comparative study across species
• Selection pressures favoring sociality

  • Habitat differences and exposure to predators
  • Dietary shifts and benefits of cooperative hunting
  • Influence of social interactions on foraging efficiency
  • Defense against threats within and between species
• Selection pressures on human ancestors

  • Predation risk
  • Cooperative hunting
  • Resource distribution
  • Intra-species conflicts
• Social behavior is essential for human well-being and has evolutionary roots
• Costs and benefits influence the evolution of sociality across species
• Understanding the selection pressures on social behavior helps explain human social tendencies
• Comparative studies with African great apes offer insights into the evolution of human sociality
• Multiple factors, including predation risk, resource distribution, and intra-species conflicts, contribute to the evolution of social behavior in human ancestors
• Characteristics of foraging societies

  • Small, semi-nomadic bands with populations ranging from 10 to 30 individuals
  • Fluid membership allows for individuals and families to shift between bands based on opportunities
  • Dense kinship networks within these small communities
• Selection pressures for sociality in ancestral humans

  • Predation risk in open habitats driving the need for social protection
  • Benefits of cooperative hunting and scavenging, potentially leading to group cohesion
  • Challenges of resource distribution and sharing, favoring social behaviors
  • Mitigation of inter-group conflicts through collective defense strategies
• Kin selection theory


  Highlights the influence of genetic relatedness on social interactions
• Role of kinship in human social behavior

  • Kinship as a fundamental organizing principle in human societies, shaping group membership and behavior
  • Kinship-based cooperation in tasks such as land clearing, planting, and harvesting among various horticulturalist groups
  • Systematic sharing of resources, including food, among kin in both foraging and food-producing societies
• Kin selection theory predicts

  Decreased selfishness and aggression among genetic relatives
• Empirical evidence from studies on domestic homicides supports the notion that individuals are less inclined to commit violence against kin
• Historical and anthropological data from various cultures further illustrate the pattern of reduced aggression toward genetic relatives
• Foraging societies provide insights into ancestral human social life, characterized by small, kin-based communities
• Kinship plays a crucial role in shaping social interactions, cooperation, and conflict resolution across various human societies
• Empirical evidence supports the predictions of kin selection theory, indicating reduced aggression and increased cooperation among genetic relatives
• Altruism


  People tend to be more altruistic towards kin compared to non-kin
• Altruistic tendencies


  Stronger in situations of dire need
• Kin selection theory explains altruistic behaviors
• Children living with genetic parents

  Experience lower stress levels compared to those living with stepparents
• Close kinship ties have a stress-reducing effect
• Reciprocity in social behavior

  • Individuals are more likely to help when the cost is low, the need is urgent, and there is potential for reciprocity
  • Humans are inclined to behave altruistically towards reciprocators
• Humans are adept at recognizing instances of cheating and avoiding interactions with potential cheaters
• Individuals can often identify potential cheaters in advance, helping to avoid wasteful altruism
• Concern for reputation


  People are concerned about their reputation as cheaters or cooperators, influencing their behavior in social interactions
• Many environmental problems resemble prisoners' dilemmas, such as the tragedy of the commons
• Environmental decisions often involve a trade-off between personal gain (cheating) and communal benefit (cooperation)
• Altruism spreads when reciprocated and when cheaters are punished, but environmental issues pose challenges as cheating may not be easily identifiable, and widespread non-cooperation complicates the acceptance of initial costs for eventual benefits
• Policy interventions for environmental cooperation

  • Adjusting costs and benefits to encourage cooperation (e.g., tax credits for electric vehicles)
  • Pollution credit programs, like those for utility companies, punish polluters and reward cooperators, fostering cooperation
• Humans naturally recognize and respond to differences in rank and status, like other social animals
• Social dominance is salient in human interactions and influences behavior, even in subtle ways
• Individuals modify their behavior based on perceived power differentials, seeking to confirm existing notions or gather accurate information depending on their perceived status relative to others