Current social networks may have been present in the earliest modern humans

In this week’s Nature, a group of researchers suggest that we share many social characteristics with humans that lived in the late Pleistocene, and that these ancient humans may have paved the way for us to cooperate with each other. Modern human social networks share several features, whether they operate within a group of schoolchildren in San Francisco or a community of millworkers in Bulgaria. The number of social ties a person has, the probability that two of a person’s friends are also friends, and the inclination for similar people to be connected are all very regular across groups of people living very different lives in far-flung places. So, the researchers asked, are these traits universal to all groups of humans, or are they merely byproducts of our modern world? They also wanted to understand the social network traits that allowed cooperation to develop in ancient communities.