Altruism as an Explanation for Human Consanguinity

Area of Science:

• Sociobiology
• Anthropology
• Population Genetics

Background:

• Human inbreeding (consanguinity) is a persistent sociobiological puzzle despite known genetic risks.
• Existing explanations for the prevalence of consanguinity in modern societies are inadequate.

Purpose of the Study:

• To propose a novel sociobiological explanation for the persistence of human inbreeding.
• To investigate the role of trust and altruism in population structure and consanguinity.

Main Methods:

• Theoretical analysis of sociobiological principles.
• Historical perspective linking Neolithic revolution to population structure.
• Exploration of trust dynamics within kinship groups versus broader social networks.

Main Results:

• The Neolithic Agrarian revolution fostered larger, more cohesive kinship groups (tribes) due to increased resource competition.
• Trust, a form of altruism, initially limited to kin, maintained small, economically poor, and consanguineous tribal structures.
• Expansion of trust beyond kin is linked to increased group size, economic wealth, and decreased consanguinity.

Conclusions:

• Limited non-kin altruism contributes to poverty, small group sizes, and inbreeding.
• The evolution of trust from kin-based to broader social networks is crucial for societal development and reduced consanguinity.
• Understanding trust dynamics offers insights into persistent human consanguinity and societal structures.