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bioRxiv · 10.1101/2025.03.17.643651

Evidence that human skill level is more reactive to developmental history than to genes or environment

Gonzalez-Forero, M.·Gomez-Robles, A.
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Abstract

A long-standing question is to what extent behaviour is determined by genes, environment, or else. Common practice estimates genetic components using heritability, which is correlational, population-level, and variously problematic to measure genetic contribution. Ideally, contributions would be quantified via experimental intervention, which is often infeasible for humans and other organisms, but possible in silico. We formulate mathematical methods to quantify contributions to phenotypic differences in silico, and apply them to an in-silico replica of human skill development and evolution. We find that, in this replica, adult skill level is more reactive to differences in developmental history than to genetic, environmental, or social differences from Homo habilis to H. sapiens. This occurs although, in this replica, adult skill level has evolved an increased reactivity to environmental and social differences, and a decreased reactivity to genetic differences, which is consistent with observation. Our results predict a window of sensitivity at menarche. They also predict that adverse genetic and environmental conditions that would developmentally yield low adult skill level can be compensated by time-specific environmental changes or slight changes in developmental history, potentially yielding outstanding adult skill level. Our analyses suggest a major capability of developmental history to influence adult human skill level.

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Gonzalez-Forero, M., Gomez-Robles, A.. 2025-03-17. Evidence that human skill level is more reactive to developmental history than to genes or environment. https://doi.org/10.1101/2025.03.17.643651

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