Environmental influences on human innovation and behavioural diversity in southern Africa 92-80 thousand years ago

Africa's Middle Stone Age preserves sporadic evidence for novel behaviours among early modern humans, prompting a range of questions about the influence of social and environmental factors on patterns of human behavioural evolution. Here we document a suite of novel adaptations dating approximately 92-80 thousand years before the present at the archaeological site Varsche Rivier 003 (VR003), located in southern Africa's arid Succulent Karoo biome. Distinctive innovations include the production of ostrich eggshell artefacts, long-distance transportation of marine molluscs and systematic use of heat shatter in stone tool production, none of which occur in coeval assemblages at sites in more humid, well-studied regions immediately to the south. The appearance of these novelties at VR003 corresponds with a period of reduced regional wind strength and enhanced summer rainfall, and all of them disappear with increasing winter rainfall dominance after 80 thousand years before the present, following which a pattern of technological similarity emerges at sites throughout the broader region. The results indicate complex and environmentally contingent processes of innovation and cultural transmission in southern Africa during the Middle Stone Age. Evidence of ostrich eggshell artefacts, long-distance transport of marine shells and heat treatment of stone tools in a marginal southern African environment 92-80 thousand years ago suggests that innovation among early human groups was sensitive to ecological variation.

Automated summary

This study found a series of novel human behavioral adaptations dating approximately from 92-80 thousand years ago at an archaeological site in southern Africa's arid region. These adaptations were not observed in contemporaneous sites in more humid regions. It suggests that early human groups' innovation was sensitive to ecological variations.