Abstract
In this contribution, we address a major puzzle in the evolution of human material culture: If maturing
individuals just learn their parental generation’s material culture, then what is the origin of key
innovations as documented in the archeological record? We approach this question by coupling a
life-history model of the costs and benefits of experimentation with a niche-construction perspective.
Niche-construction theory suggests that the behavior of organisms and their modification of
the world around them have important evolutionary ramifications by altering developmental
settings and selection pressures. Part of Homo sapiens’ niche is the active provisioning of children
with play objects — sometimes functional miniatures of adult tools — and the encouragement of
object play, such as playful knapping with stones. Our model suggests that salient material culture
innovation may occur or be primed in a late childhood or adolescence sweet spot when cognitive
and physical abilities are sufficiently mature but before the full onset of the concerns and costs
associated with reproduction. We evaluate the model against a series of archeological cases and
make suggestions for future research.