Garvin Heather M, Elliott Marina C, Delezene Lucas K, Hawks John, Churchill Steven E, Berger Lee R, Holliday Trenton W
Department of Anthropology/Archaeology, Mercyhurst University, 501 East 38(th) Street, Erie, PA 16546, USA; Department of Applied Forensic Sciences, Mercyhurst University, 501 East 38(th) Street, Erie, PA 16546, USA; Evolutionary Studies Institute, University of the Witwatersrand, 1 Jan Smuts Avenue, Braamfontein, 2000, Johannesburg, South Africa.
Evolutionary Studies Institute, University of the Witwatersrand, 1 Jan Smuts Avenue, Braamfontein, 2000, Johannesburg, South Africa.
J Hum Evol. 2017 Oct;111:119-138. doi: 10.1016/j.jhevol.2017.06.010. Epub 2017 Aug 4.
Homo erectus and later humans have enlarged body sizes, reduced sexual dimorphism, elongated lower limbs, and increased encephalization compared to Australopithecus, together suggesting a distinct ecological pattern. The mosaic expression of such features in early Homo, including Homo habilis, Homo rudolfensis, and some early H. erectus, suggests that these traits do not constitute an integrated package. We examined the evidence for body mass, stature, limb proportions, body size and dental size dimorphism, and absolute and relative brain size in Homo naledi as represented in the Dinaledi Chamber sample. H. naledi stature and body mass are low compared to reported values for H. erectus, with the exception of some of the smaller bodied Dmanisi H. erectus specimens, and overlap with larger Australopithecus and early Homo estimates. H. naledi endocranial volumes (465-560 cc) and estimates of encephalization quotient are also similar to Australopithecus and low compared to all Homo specimens, with the exception of Homo floresiensis (LB1) and the smallest Dmanisi H. erectus specimen (D4500). Unlike Australopithecus, but similar to derived members of genus Homo, the Dinaledi assemblage of H. naledi exhibits both low levels of body mass and dental size variation, with an estimated body mass index of sexual dimorphism less than 20%, and appears to have an elongated lower limb. Thus, the H. naledi bauplan combines features not typically seen in Homo species (e.g., small brains and bodies) with those characteristic of H. erectus and more recent Homo species (e.g., reduced mass dimorphism, elongated lower limb).
与南方古猿相比，直立人和后来的人类体型增大、两性异形减小、下肢拉长且脑化增强，这共同表明了一种独特的生态模式。这些特征在早期人属物种（包括能人、鲁道夫人和一些早期直立人）中的镶嵌式表达，表明这些性状并非一个完整的组合。我们研究了迪纳莱迪洞穴样本中所代表的纳莱迪人在体重、身高、肢体比例、体型和牙齿大小两性异形以及绝对和相对脑容量方面的证据。与报道的直立人值相比，纳莱迪人的身高和体重较低，但一些体型较小的德马尼西直立人标本除外，且与体型较大的南方古猿和早期人属的估计值有重叠。纳莱迪人的颅内容积（465 - 560立方厘米）和脑化商估计值也与南方古猿相似，与所有其他人类标本相比都较低，但弗洛勒斯人（LB1）和最小的德马尼西直立人标本（D4500）除外。与南方古猿不同，但与人类属的衍生成员相似，纳莱迪人的迪纳莱迪组合表现出较低的体重和牙齿大小变异水平，估计的两性异形体重指数小于20%，并且似乎下肢拉长。因此，纳莱迪人的身体结构将人类物种中不常见的特征（如小脑袋和小身体）与直立人和更近代人类物种的特征（如减小的体型两性异形、拉长的下肢）结合在了一起。
