At some point, from around 40,000 years ago in Europe, we see evidence of these behaviourally modern humans in a sudden flourishing of cultural artifacts in the archaeological record. So what caused anatomically modern Homo sapiens to turn into behaviourally modern people? Was it a genetic switch that created a different type of cognitively superior person?
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The reason for these bursts in cultural activity is not to do with changes in our ancestors’ individual brains but in their collective brains – changes resulting from human demography and networks.
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[T]he most important decider seems to be group size: usually, the bigger the group, the bigger the diversity of cultural practices. Those that are particularly successful at increasing a society’s population – such as practices that improve nutrition, fertility or reduce infant mortality – will, of course, produce more carriers of that practice, so spread faster and further… Geneticists recently discovered that the greatest population boom in prehistory occurred 40,000 to 50,000 years ago, which helps to explain a swathe of cultural explosions seen at this time, from present-day Germany to Indonesia.
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The great flowering of culture we enjoy from our Cro-Magnon ancestors was not evidence of a cleverer, ‘more evolved’ people but because the demographic, social, environmental and cultural changes that occurred at this time in Europe drove cultural complexity.
