Dunbar's number is based on the correlation between encephalization quotient and group size http://anthropology.net/2013/06/26/simulating-the-social-brain-hypothesis/ …pic.twitter.com/rVYADZlWP2
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@Outsideness @sarahdoingthing Lots of variables, though - ending ice age, plant domestication & dietary changes, species intermingling, etc
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