On the evolutionary origins of equity

Area of Science:

• Evolutionary biology
• Behavioral economics
• Social psychology

Background:

• Equity, defined as reward according to contribution, is a fundamental aspect of human fairness.
• While the evolutionary origins of fairness are studied, the evolutionary rationale behind equity remains unclear.

Purpose of the Study:

• To investigate the evolutionary rationale behind equity in human cooperation.
• To model how cooperative partner selection influences the evolution of equity preferences.

Main Methods:

• Agent-based simulations of a cooperating population dividing resources.
• Analytical modeling of partner selection based on resource division willingness.
• Extended simulations incorporating neural networks to validate findings.

Main Results:

• Converging evidence indicates equity is the optimal evolutionary strategy for maximizing fitness.
• Individuals maximize fitness by dividing benefits proportionally to relative contributions.
• The necessity of being chosen as a cooperative partner drives selection for equity preferences.

Conclusions:

• Equity preferences evolve as a consequence of partner selection in cooperative environments.
• This model provides a potential evolutionary explanation for the widespread human preference for equity.
• Further research is needed to address model limitations and empirical discrepancies.