How monogamous are humans compared to other animals?
What's the story
A recent study by researchers from the University of Cambridge has shed light on human monogamy in comparison to other animal species. The team, led by evolutionary anthropologist Mark Dyble, analyzed sibling data across different species and historical human populations. Their findings, published in the journal Proceedings of the Royal Society B, suggest that humans are more monogamous than our primate cousins but less so than beavers.
Research methodology
Monogamy ratings and sibling proportions
The researchers used a computational model to analyze the proportion of full siblings (those sharing both parents) versus half-siblings across several animal species and human populations. They found that species and societies with higher monogamy rates tend to have more full siblings. On the other hand, polygamous or promiscuous species produce more half-siblings. This method helped them estimate monogamy ratings for different species, including humans.
Monogamy ranking
Humans rank 7th in monogamy among 11 species
The study found that beavers are slightly more monogamous than humans, with a monogamy rating of 72% compared to humans' 66%. This puts humans in the "premier league" of monogamy along with meerkats (60%). However, dolphins and chimpanzees had a much lower monogamy rating of just 4%, while mountain gorillas came in at 6%. Overall, humans ranked seventh out of the 11 species studied that are said to be socially monogamous or favor long-term pair bonds.
Cultural variation
Study highlights diversity in human mating and marriage practices
Dyble calculated the human monogamy rates using genetic data from archeological sites and ethnographic data from 94 different human societies. This highlights the wide variation in mating and marriage practices across cultures. He said, "While anthropologists are rightly interested in understanding this diversity, sometimes there is value in stepping back and considering species-wide patterns and how we compare as just another mammal."
Scientific endorsement
Study supports monogamy as dominant mating pattern for humans
The findings of the study support the scientific view that monogamy is the dominant mating pattern for humans. Dyble said he was "not surprised" to find that the average human proportion of full siblings was in line with other monogamous mammals. However, he was surprised by the "complete separation between humans and non-monogamous mammals," noting that even societies with the lowest proportions of full siblings were still higher than those of non-monogamous mammal species.