Infidelity appears to be common in mammals that live in pairs. But new genetic tests suggest that Azara’s owl monkeys are unusually faithful.
Scientists studied 35 infants born to 17 owl monkey pairs and found that in all cases the youngsters were being raised by their biological parents. Data from the owl monkeys and 14 other species showed that the more involved the males were in raising an infant, the more likely the males were to be faithful, the team reports March 18 in Proceedings of the Royal Society B.
Owl monkeys are the only primates and one of five mammal species, including coyotes and California mice, that don’t seem to cheat, according to genetic studies. The evolution of animals’ sexual fidelity is probably linked to the intensity of male care, the researchers suggest.