Abstract An enduring challenge for the human evolutionary sciences is to integrate the palaeoanthropological record of human evolution and speciation with the archaeological record of change and differentiation in hominin lifeways. The simplest hypothesis, and therefore an attractive hypothesis, is that change is made possible by, and reflects, evolutionary change in the capacity of individual humans. The very long-term trend of increasing diversity and sophistication of technical and social lifeways (albeit with noise and periods of stasis) reflects long-term trends of increasing cognitive capacity linked to bipedality, followed by body size increase, encephalization and slow life history. We suggest instead that the long-term trend sees a gradual decoupling of human lifeways from the intrinsic capacities of individual people. We develop this view through an analysis of the Middle Stone Age and behavioural modernity, arguing that these depend on mosaics of social and individual factors, none clearly connected to specific evolved changes in individual humans.
Sterelny et al. (Fri,) studied this question.