High fidelity: human mating habits near top of monogamy league, study finds

Humans are playing in the premier league of monogamous mammals, according to a new ranking of animals based on their reproductive habits, but we may need a new manager to beat the beavers.

- Ian Sample

In the study from the University of Cambridge, humans ranked 7th out of 35 species on the monogamy scale, pipping white-handed gibbons and meerkats, but lagging behind moustached tamarins and Eurasian beavers. Dr Mark Dyble, an evolutionary anthropologist at Cambridge, said humans sit comfortably in the top flight for monogamous species, but the vast majority of mammals take “a far more promiscuous approach to mating”.

Animals in the lower ranks include feral cats, bottlenose dolphins and our close genetic relatives, chimpanzees and mountain gorillas. Scotland’s Soay sheep is at the bottom owing to each ewe mating with several rams.

Scientists have reported rates of monogamy for human and animal populations before, but Dyble wanted to know where humans sat relative to other mammals. To do this, he analysed genetic data from animal and human studies and calculated the proportions of full versus half-siblings for each.

Societies and animals with higher levels of monogamy tend to produce more siblings that share the same parents, while those with more promiscuous mating habits are likely to have a higher proportion of half-siblings.