Humans sit surprisingly high in the mammal monogamy rankings, placing 7th out of 35 species in a new Cambridge University study. By analysing genetic data and sibling relationships across species, researchers found humans have 66% full siblings, putting us above meerkats and gibbons but below more faithful species like Eurasian beavers (72%).
Most mammals are far less monogamous — chimpanzees and dolphins, for example, scored under 5%. The study suggests human monogamy evolved unusually compared with our closest relatives, possibly linked to paternal care and child protection.
Researchers note that culture and social expectations shape human relationships heavily, with many societies practising serial monogamy despite biological tendencies.
In the animal kingdom’s loyalty league, humans perform well — but the beavers keep their crown.
