Onager Asiatic cheetahs, and possibly bears, though they may have mostly preyed only on onager foals. In India, mugger crocodiles can be great threats to onagers during migratory river crossings. Currently, the biggest predator for onagers are gray wolves. About 23% of prey proportion of gray wolves were on the Asian wild ass. However, like most equids, they are known to have antipredator protection. Groups of stallions cooperate and try to chase off predators. If threatened, onagers defend themselves and violently kick at the incoming predator. The greatest threat facing the onager is poaching for meat and hides, and in some
Onager ancestor of all modern equids (members of the genus "Equus") lived around 5.6 (3.9–7.8) million years ago (Mya). Direct paleogenomic sequencing of a 700,000-year-old middle Pleistocene horse metapodial bone from Canada implies a more recent 4.07 Mya for the most recent common ancestor within the range of 4.0 to 4.5 Mya. The oldest divergencies are the Asian hemiones (subgenus "E. (Asinus)", including the kulan, onager, and kiang), followed by the African zebras (subgenera "E. (Dolichohippus)", and "E. (Hippotigris)"). All other modern forms including the domesticated horse (and many fossil Pliocene and Pleistocene forms) belong to the subgenus "E. (Equus)" which