Translation of epigenetic rules of individual behavior into ethnographic patterns.

The pivotal process in gene-culture coevolution is envisaged to be the evolution of behavioral epigenesis. From premises based on the known properties of enculturation and usage diffusion within societies, a probabilistic model is constructed to estimate the degree to which rules governing individual development canalize ethnographic curves (the probability density distributions of societies engaged in varying patterns of usage). The results indicate that under most conceivable conditions the translation from individual epigenesis to social pattern is amplified, to an extent that differences in bias too faint to be detected in ordinary developmental studies can generate conspicuous variation in the ethnographic curves. Examples are cited of sufficiently biased epigenesis in human behavior.