The Impact of Climate Change on the Evolution of Cultural Transmission Strategies in the Human Lineage

To investigate whether climate influenced the evolution of cultural transmission in the hominin lineage, we compared transmission strategies associated with archaeological innovations dated between 3.3 Ma and 6 ka to high-resolution paleoclimate records. Transmission was assessed across three dimensions: spatial (proximity between learner and model), temporal (degree of modularity or sequencing), and social (selectivity in knowledge transfer). Results show that transmission modes correlate with long-term climatic phases, not with the rate of climatic variability. Within a long-term trend toward increasingly complex transmission, globally cooler phases favoured low-investment, observation-based strategies, whereas globally warmer phases promoted structured, explanation-based, and modular transmission. The strongest association between modes of cultural transmission and climate occurs between 500–200 ka, followed by progressive decoupling, particularly after 50 ka, when cultural transmission increasingly follows its own dynamics.