And early human societies probably did breastfeed their children beyond a year. (scienceofmom.com)
Dancing may have similar effects, he says, and — like singing — is thought to have been an important part of early human societies. (sciencemag.org)
The more strongly we identify with a particular group, the more vehemently we defend its members and ideals — a trait that experts think evolved along with early human society. (scientificamerican.com)