That’s the idea behind a study by University of Oxford and the University of Auckland researchers in PhysOrg. The scientists found that our ability to live in lots of different social settings is what sets us apart from other primates:
The study analysed patterns of social groups among living primates, as well as examining the ‘the root’ of the family tree, in 217 primate species. The researchers then used Bayesian data modelling to reconstruct the most likely explanation for how the grouping behaviour of primates evolved over 74 million years.
Their key finding is that the main step change in social behaviour occurred when primates switched from being mainly active at night to being more active during the day. Primates started out as solitary foragers as by night they could survive by moving quietly on their own in the dark. However, once they switched to daytime activity, they could be seen and were more vulnerable to attack by predators unless they could show strength in numbers. This research paper provides evidence to show that this switch in activity coincided with a significant change in social behaviour as primates started to ‘gang up’ for the first time.
The researchers conclude that only humans have had the flexibility to live in a range of different, complicated social settings. Throughout history, humans have lived in monogamous and polygamous societies; in nuclear family and extended family groups. Beyond the home, they have socialised in different work settings, as well as being part of the complicated social structure of wider human society.