New study by scientists at the University of Oxford, England, challenges some common beliefs regarding social behavior. From a new survey of social structure across the family tree of 217 primate species, they reached the conclusion that genetics may play a bigger part in shaping sociality than environment. The findings also rebut widespread ideas about social behavior, for example theories about the way complex societies are formed or the social brain hypothesis – that intelligence and brain volume increase with group size.
This led to the conclusion that social structure is determined by inherited genes and not ecology. The scientists also suggest that sociality might have started 52 million years ago, and that it would be the result of primates shifting their activity from nighttime to daytime. In doing so, they had to work in groups in order to be safe. This fact questions the social brain hypothesis, as it denies a steady progression from small groups to large ones.