Prehistoric humans may have become monogamous to avoid catching sexually transmitted infections, according to new research from Ontario’s University of Waterloo.
The study, published in Nature Communications, used computer models to simulate the evolution of different mating behaviours, based on demographics and disease transmission.
Researchers found that in small groups of early hunter-gatherers, a few men monopolized sex with several women to boost their number of offspring. But as human societies evolved and grew larger, the research found, STIs tended to hang around due to “overlapping” polygamous relationships.
Infertility from syphilis, chlamydia and gonorrhoea would have been endemic. So it became safer to stick to just one sexual partner – and punish those who didn’t – if the group was to keep procreating.
And thus monogamy was born. Or was it?
The research notes there may have been other factors at play – not least what women had to say about it all… or that they might have liked to have more than sexual partner too.
Let’s just say the next instalment in the scientific analysis of human monogamy should make for interesting reading…