For anthropologists , socially imposed human monogamy is an evolutionary conundrum , as it exacts a high price from the individuals who undertake it. Until now it was thought that the appearance of agriculture in the Neolithic and the establishment of broad stable societies had pushed humans to live with a partner for life, however a new study from the University of Waterloo (Canada) stipulates that the Sexually transmitted diseases played a crucial role in this social behavior.
For Chris Bauch, who has led the research, in prehistory, when humans began to develop societies formed by larger groups thanks to the possibility of accumulating food thanks to the domestication of plants and crops, different groups in different parts of the world. The world developed social norms that led to the transition from polygamy to monogamy . The frequent presence of sexually transmitted diseases (STDs) and peer pressure had a lot to do with this. In smaller societies, these sexual infections did not persist for long , tended to disappear from various causes, and therefore polygamy was not a disadvantage. However, in large populations, infections are resistant and spread more, so polygamous sexual behavior implies more risk than monogamy, since it increases the possibility of infection.
In primitive hunter-gatherer populations it was normal for a few males to monopolize mating with multiple females in order to increase the offspring. In those small societies with a maximum of 30 sexually mature individuals, the outbreaks of sexually transmitted infections were short-lived and did not have much importance in social development. But in large groups, STDs became endemic, with a negative impact on fertility.
