Abstract

By expanding the value of what individuals produce, economic exchanges are recognized as driving the wide diversity of economic activities seen in human societies. Since productivity depends on both chosen roles and innate abilities, we ask whether exchange could have influenced human evolution by promoting genetic diversity. We model a system where individuals produce and exchange goods under Walrasian equilibrium, with abilities determined by an evolving genetic trait. Using the adaptive dynamics approach, we analyse how exchange shapes evolutionary pressures on this trait. Our analysis demonstrates that exchange consistently promotes the maintenance of genetic diversity through negative frequency-dependent selection, and that it can generate stable polymorphism when the production of goods requires different abilities. Importantly, we establish that the mode of exchange matters: markets, where individuals can switch trading partners, promote genetic diversity under broader conditions than when exchange occurs in isolated pairs. Finally, we show that genetic diversity and economic specialisation can co-evolve, each facilitating the emergence of the other under a wider range of conditions. Our findings suggest that economic exchanges play a crucial role in fostering biological diversity and offer insights into how a cultural phenomena, here economic systems, may have shaped human evolution.

Reference

Luis Santos-Pinto, “How Economic Exchange Shapes Human Genetic Diversity”, IAST Lunch Seminar, Toulouse: IAST, March 14, 2025, 12:45–13:45, room Auditorium 4 (First floor - TSE building).