Evolutionary Economics http://lists.repec.org/mailman/listinfo/nep-evo Evolutionary Economics 2026-06-29 What explains intensive kinship? Natural environment, religion, and the state https://d.repec.org/n?u=RePEc:zbw:qucehw:341402&r=&r=evo This paper studies the determinants of intensive kinship norms in human societies throughout the world. We expand the existing literature by considering three separate determinants of kinship intensity: the natural environment, religion, and state rule. Our novel methodology takes advantage of recent datasets, linking the location of human societies from the Ethnographic Atlas to geospatial data on the territorial span of states throughout human history. For religion, we find that Islam has an effect of similar magnitude but opposite direction to Christianity. For state rule, we find that only states with high levels of institutional development lead to less intensive kinship norms. Angeles, Luis Elizalde, Aldo kinship norms, natural environment, religion, Islam, Christianity, state rule, institutional development 2026 Climate and Prehistoric Migration https://d.repec.org/n?u=RePEc:nbr:nberwo:35371&r=&r=evo What factors drove human migration before modern states, markets, and borders? We develop a sorting framework in which climate-specific subsistence knowledge depreciates with ecological distance. To test this, we use ancient DNA identity-by-descent segments to construct bilateral migration flows across Western Eurasia over the last 10, 000 years. We document three main findings. First, migration flows decline with differences in growing degree days, precipitation, and soil characteristics between origins and destinations. Second, the binding factor varies across subsistence systems: farmers exhibit strong thermal and soil matching, while pastoralists match most strongly on precipitation. Third, periods of warming increase farmer expansion while cooling increases pastoral expansion in patterns that recover known archaeological migration episodes. Migration also acts as a margin of climate adaptation: populations exposed to temperature change move to destinations that partly offset the shift. Peter Huybers Marco Tabellini Charles A. Taylor Francesco Toti 2026-06 The trust game: A Historical and Methodological Analysis at the Frontier of Experimental and Behavioral Economics https://d.repec.org/n?u=RePEc:hal:journl:hal-05659421&r=&r=evo Nicolas Camilotto Trust, Trust Game 2026-05-26 Algorithmic cooperation: A comparison with human play in the infinitely repeated prisoner's dilemma https://d.repec.org/n?u=RePEc:zbw:dicedp:341427&r=&r=evo Reinforcement learning algorithms play an increasingly important role in economic situations. These situations are often strategic, and the artificial intelligence may or may not be cooperative. We compare human and algorithmic cooperation rates in the infinitely repeated two-player prisoner's dilemma and study which strategies they choose to cooperate and punish deviations. Through a sequence of computational Q-learning and human-player experiments, we find that our Q-learning algorithms tend to cooperate less than humans, particularly when cooperation is risky or not incentive-compatible. Algorithms often use different strategies than humans, leading to distinct on- and off-path behavior. Kasberger, Bernhard Martin, Simon Normann, Hans-Theo Werner, Tobias Artificial intelligence, cooperation, Q-learning, repeated prisoner's dilemma 2026