当前位置:科学网首页 > 小柯机器人 >详情
科学家揭示东非已知最古老智人的年龄
作者:小柯机器人 发布时间:2022/1/16 13:25:54

近日,英国剑桥大学Céline M. Vidal等研究人员揭示东非已知最古老智人的年龄。相关论文于2022年1月12日在线发表于国际学术期刊《自然》。

据研究人员介绍,为确定非洲东部最古老的现代人类化石(来自埃塞俄比亚的Omo-Kibish和Herto)的年代,研究人员已经利用了各种测年证据,包括地层相关凝灰岩的40Ar/39Ar年龄。这些化石的年龄一般报告为:Kibish Omo I的年龄约为19.7万年,Herto人的年龄约为16至15万年。然而,支撑这些估计的地层关系和头盖骨的相关性受到了质疑。
 
研究人员报告了地球化学分析,将卡莫亚人遗址(KHS)凝灰岩与埃塞俄比亚主裂谷的沙拉火山的一次重大爆炸性喷发联系起来,该凝灰岩确凿地覆盖在包含Omo I的奥莫-基比什地层的成员之上。通过对这次喷发的近端沉积物进行测年,研究人员得到了奥莫化石的新的最低年龄为233±22千年。与以前的论点相反,研究人员还表明,KHS凝灰岩与另一个广泛的凝灰岩层(即Waidedo Vitric凝灰岩)不相关,因此不能锁定Herto化石的最低年龄。这项研究将非洲东部已知最古老智人化石的年龄推到大约20万年前,这与现代人类血统更古老的独立证据是一致的。
 
附:英文原文
 
Title: Age of the oldest known Homo sapiens from eastern Africa

Author: Vidal, Cline M., Lane, Christine S., Asrat, Asfawossen, Barfod, Dan N., Mark, Darren F., Tomlinson, Emma L., Tadesse, Amdemichael Zafu, Yirgu, Gezahegn, Deino, Alan, Hutchison, William, Mounier, Aurlien, Oppenheimer, Clive

Issue&Volume: 2022-01-12

Abstract: Efforts to date the oldest modern human fossils in eastern Africa, from Omo-Kibish1,2,3 and Herto4,5 in Ethiopia, have drawn on a variety of chronometric evidence, including 40Ar/39Ar ages of stratigraphically associated tuffs. The ages that are generally reported for these fossils are around 197thousand years (kyr) for the Kibish Omo I3,6,7, and around 160–155kyr for the Herto hominins5,8. However, the stratigraphic relationships and tephra correlations that underpin these estimates have been challenged6,8. Here we report geochemical analyses that link the Kamoya’s Hominid Site (KHS) Tuff9, which conclusively overlies the member of the Omo-Kibish Formation that contains Omo I, with a major explosive eruption of Shala volcano in the Main Ethiopian Rift. By dating the proximal deposits of this eruption, we obtain a new minimum age for the Omo fossils of 233±22kyr. Contrary to previous arguments6,8, we also show that the KHS Tuff does not correlate with another widespread tephra layer, the Waidedo Vitric Tuff, and therefore cannot anchor a minimum age for the Herto fossils. Shifting the age of the oldest known Homo sapiens fossils in eastern Africa to before around 200thousand years ago is consistent with independent evidence for greater antiquity of the modern human lineage10.

DOI: 10.1038/s41586-021-04275-8

Source: https://www.nature.com/articles/s41586-021-04275-8

期刊信息

Nature:《自然》,创刊于1869年。隶属于施普林格·自然出版集团,最新IF:43.07
官方网址:http://www.nature.com/
投稿链接:http://www.nature.com/authors/submit_manuscript.html