Schwartz J H, Tattersall I
Department of Anthropology, University of Pittsburgh, Pittsburgh, PA 15260, USA. jhs+@pitt.edu
J Hum Evol. 2000 Mar;38(3):367-409. doi: 10.1006/jhev.1999.0339.
Although the presence of a "chin" has long been recognized as unique to Homo sapiens among mammals, both the ontogeny and the morphological details of this structure have been largely overlooked. Here we point out the essential features of symphyseal morphology in H. sapiens, which are present and well-defined in the fetus at least as early as the fifth gestational month. Differences among adults in expression of these structures, particularly in the prominence of the mental tuberosity, are developmental epiphenomena and serve to emphasize the importance of studying this region in juveniles whenever possible. A survey of various middle to late Pleistocene fossil hominids for which juveniles are known reveals that these features are present in some late Pleistocene specimens assigned to H. sapiens, but not in all of the presumed anatomically modern H. sapiens (i.e., Qafzeh 8, 9, and 11). The adult specimens from Skhūl, as well as the adult Qafzeh 7 specimen, are similarly distinctive in symphyseal morphology. Neanderthals are quite variable in their own right, and they as well as other middle to late Pleistocene fossils lack the symphyseal features of H. sapiens. Some of the latter are, however, seen in the Tighenif (Ternifine) mandibles.
尽管“下巴”的存在长期以来被认为是人类在哺乳动物中独有的特征，但该结构的个体发育和形态细节在很大程度上被忽视了。在此我们指出了智人耻骨联合形态的基本特征，这些特征至少在妊娠第五个月时在胎儿中就已存在且清晰可辨。成年人在这些结构表达上的差异，尤其是颏结节的突出程度，是发育的附带现象，这进一步强调了尽可能研究青少年这个区域的重要性。对已知有青少年标本的各种中更新世晚期至晚更新世化石人类的调查显示，这些特征在一些被归类为智人的晚更新世标本中存在，但并非所有被认为是解剖学意义上现代智人的标本都有（即卡夫泽8号、9号和11号）。来自斯虎尔的成年标本以及卡夫泽7号成年标本在耻骨联合形态上同样独特。尼安德特人本身差异很大，他们以及其他中更新世晚期至晚更新世化石都缺乏智人的耻骨联合特征。然而，在提格尼夫（特尔尼芬）下颌骨中可以看到其中一些特征。
