Rosas A, Bermúdez de Castro J M
Department of Paleobiology, Museo Nacional de Ciencias Naturales, Madrid, Spain.
Am J Phys Anthropol. 1998 Oct;107(2):145-62. doi: 10.1002/(SICI)1096-8644(199810)107:2<145::AID-AJPA2>3.0.CO;2-U.
The recent discovery of unexpectedly ancient human remains has fuelled interest about the first dispersion of Homo outside Africa. The Dmanisi mandible is perhaps one of the most interesting findings, as it supposedly represents one of the oldest hominids outside of Africa. Recently, different interpretations have been published about this specimen. Our comparison of the Dmanisi mandible with a large sample of mandibles and teeth has led us to a new interpretation. In our view, the Dmanisi mandible exhibits a unique combination of traits. Some of its features, taken in isolation, may be attributed to morphological extremes within the genus Homo. The architecture of the mandible as well as the morphology and dimensions of incisors, canines, and P3s are clearly primitive. However, dental traits such as the reduction of the talonid in the P4s and a distally decreasing molar series seems to be derived. Some combinations of these traits are found in specimens of Homo ergaster and differ from those generally present in later hominids. Thus, we propose that the Dmanisi mandible might be taxonomically classified as Homo sp. indet. (aff. ergaster). Furthermore, some aspects of the dentition in Dmanisi display close similarities to Asian Homo erectus. If the 1.8-1.6 Myr dating for the Dmanisi mandible is correct, the differentiation of the Asian branch of the genus Homo could be regarded as a very ancient event.
近期意外发现的年代异常久远的人类遗骸引发了人们对人类首次走出非洲扩散情况的兴趣。德马尼西下颌骨可能是最有趣的发现之一，因为它据说是非洲以外最古老的原始人类之一。最近，关于这个标本出现了不同的解读。我们将德马尼西下颌骨与大量下颌骨和牙齿样本进行比较后得出了一种新的解读。我们认为，德马尼西下颌骨展现出了独特的特征组合。它的一些特征单独来看，可能归因于人类属内的形态极端情况。下颌骨的结构以及门齿、犬齿和P3的形态与尺寸明显较为原始。然而，诸如P4跟座的缩小以及磨牙列向远中方向递减等牙齿特征似乎是衍生而来的。这些特征的某些组合在匠人标本中也有发现，且与后来原始人类中普遍存在的特征不同。因此，我们提议将德马尼西下颌骨在分类学上归类为待定种（类似匠人）。此外，德马尼西牙齿的某些方面与亚洲直立人表现出密切的相似性。如果德马尼西下颌骨180万至160万年前的年代测定是正确的，那么人类属亚洲分支的分化可能被视为一个非常古老的事件。
