Researchers studying baboons in Ethiopia said the primates are prone to having sexual affairs and attempt to hide them from their partners.
Aliza le Roux, leader of the study, said the team discovered that while the dominant male of a gelada baboon group has exclusive mating rights with the females under his power, they are prone to having "extra-marital" affairs with other males, The Sun reported Friday.
The team said the females were very vocal when mating with the leader but quiet when having their affairs.
Le Roux said one-in-five of the cheaters were found and punished with the dominant male showing acts of aggression, including trying to bite, against the cheaters.
"This shows humans aren't alone when it comes to infidelity and there are evolutionary roots to our behavior," le Roux said.