科学家2015年3月4日在美国《科学》杂志上报告说,他们在东非发现了一块带着5颗完整牙齿的不完整下颌骨,这是迄今发现的最古老的人属化石,有可能改写人类的进化时间表。这块下颌骨2013年出土于埃塞俄比亚阿法尔州。分析表明,该化石可追溯至275万年至280万年前,比此前发现的最早的人属化石早了约40万年。由于有关化石极度缺乏,考古学家此前认为,人属可能直到230万年 Scientists in the United States, March 4, 2015 report in Science that they found an incomplete mandible with five intact teeth in East Africa, the oldest humanoid fossil discovered to date, possibly rewritten Human evolutionary timetable. The mandible was unearthed in Ethiopian Afar state in 2013. Analysis shows that the fossil dates back to 2.75 to 2.8 million years ago, about 400,000 years earlier than the earliest human fossils previously discovered. Archaeologists had previously thought that the human race could last up to 2.3 million years because of the extreme lack of fossils