The available fossil evidence indicates that both the hominoid and cercopithecoid clades originated in Africa. The ultimate position of "Lufengpithecus" in hominoid phylogeny requires more research. Early hominoid fossils have been found here. The evolution of hominoid communication is evident through chimpanzee 'hoo' vocalizations and alarm calls. The discoverers described Anoiapithecus brevirostris as a hominoid (superfamily Hominoidea) in the dryopithecine tribe. Alarm calls in chimpanzees also point to the evolution of hominoid language. The history of hominoid taxonomy is complex and somewhat confusing. Within two weeks, nearly 40% of the hominoid skeleton was identified and cataloged. However, further studies have shown that "Dendropithecus" lacks derived hominoid traits. "Nacholapithecus kerioi" is a hominoid known from the Aka Aiteputh Formation, in Nachola, Northern Kenya. This is twice what would be expected in a hominoid with a human-sized brain. The hominoid "Dryopithecus" appeared in Europe together with the Asian suid "Propotamochoerus".