Asfaw B, White T, Lovejoy O, Latimer B, Simpson S, Suwa G
Rift Valley Research Service, Post Office Box 5717, Addis Ababa, Ethiopia.
Science. 1999 Apr 23;284(5414):629-35. doi: 10.1126/science.284.5414.629.
The lack of an adequate hominid fossil record in eastern Africa between 2 and 3 million years ago (Ma) has hampered investigations of early hominid phylogeny. Discovery of 2.5 Ma hominid cranial and dental remains from the Hata beds of Ethiopia's Middle Awash allows recognition of a new species of Australopithecus. This species is descended from Australopithecus afarensis and is a candidate ancestor for early Homo. Contemporary postcranial remains feature a derived humanlike humeral/femoral ratio and an apelike upper arm-to-lower arm ratio.
200万至300万年前（Ma）东非地区缺乏足够的原始人类化石记录，这阻碍了对早期原始人类系统发育的研究。从埃塞俄比亚中阿瓦什地区哈塔地层发现的250万年前的原始人类头骨和牙齿化石，使一种新的南方古猿物种得以被识别。该物种是阿法南方古猿的后裔，是早期人类的候选祖先。同时期的颅后化石特征显示出类似人类的肱骨/股骨比例以及类似猿类的上臂/下臂比例。
