Fossil Jaw Grows Orangutan Family Tree, Scientists Say
Researchers believe a jawbone found in Khorat, Thailand, and dating to the Late Miocene era between seven and nine million years ago belongs to a newly discovered relative of orangutans. The jawbone from the new hominoid, named Khoratpithecus piriyai, is similar to the lower jaw, or mandible, of modern orangutans. And like today's orangutans, the ancient jawbone shows no evidence of anterior digastric muscles, the tell-tale muscles used to lower the jaw in most other primates.