Braga J
U.M.R. 152 du C.N.R.S., Musée de l'Homme, Paris, France.
Am J Phys Anthropol. 1998 Feb;105(2):121-35. doi: 10.1002/(SICI)1096-8644(199802)105:2<121::AID-AJPA2>3.0.CO;2-Y.
For a better understanding of early hominid growth patterns, we need to compare skeletal maturation among humans and chimpanzees. This study provides new data on variation of the incisive suture closure in extant species to facilitate the understanding of growth patterns among South African Plio-Pleistocene hominids. The complete anterior closure of the incisive suture occurs early during human life, mostly before birth. In contrast, in chimpanzees a complete anterior closure occurs mostly after the eruption of either the first permanent molars (pygmy chimpanzees) or the third molars (common chimpanzees). The first aim of this study is to test whether the patterns of closure of both the anterior and palatal components of the incisive suture in chimpanzees accurately mirror their polytypism by investigating 720 museum specimens of known geographical origin. Then we use the data gleaned from the incisive suture closure in chimpanzees to determine whether there are different growth patterns among South African Plio-Pleistocene hominids and to interpret them. Results about the pattern of incisive suture closure are consistent with the differences among chimpanzees as revealed by molecular data. Thus, the variation in chimpanzee patterns of incisive suture closure facilitates the interpretation of morphology in South African fossil hominids. In Australopithecus (Paranthropus) robustus as compared to Australopithecus africanus, the complete anterior closure and, probably, the complete palatal closure of the incisive suture occurs during early life in the same way as they occur in humans. Moreover, the closure pattern observed on Stw 53, a supposed early Homo from Sterkfontein Member 5, is similar to that seen in A. africanus and in chimpanzees. Thus, with respect to the anterior component of the incisive suture, A. africanus and Stw 53 retain the primitive feature for which A. (P.) robustus and Homo share the derived character state. Finally, it is worth noting that the Taung child does not show the robust condition.
为了更好地理解早期原始人类的生长模式，我们需要比较人类和黑猩猩的骨骼成熟情况。本研究提供了关于现存物种中切牙缝闭合变异的新数据，以促进对南非上新世 - 更新世原始人类生长模式的理解。切牙缝的完全前部闭合在人类生命早期出现，大多在出生前。相比之下，在黑猩猩中，完全前部闭合大多在第一恒磨牙（侏儒黑猩猩）或第三恒磨牙（普通黑猩猩）萌出之后发生。本研究的首要目的是通过调查720个已知地理来源的博物馆标本，测试黑猩猩切牙缝前部和腭部成分的闭合模式是否准确反映其多型性。然后我们利用从黑猩猩切牙缝闭合中收集的数据，确定南非上新世 - 更新世原始人类之间是否存在不同的生长模式并对其进行解读。关于切牙缝闭合模式的结果与分子数据所揭示的黑猩猩之间的差异一致。因此，黑猩猩切牙缝闭合模式的变异有助于解读南非化石原始人类的形态。与南方古猿相比，粗壮傍人切牙缝的完全前部闭合以及可能的完全腭部闭合在生命早期就已出现，方式与人类相同。此外，在斯泰克方丹5号成员出土的疑似早期人属标本Stw 53上观察到的闭合模式，与南方古猿和黑猩猩的相似。因此，就切牙缝的前部成分而言，南方古猿和Stw 53保留了原始特征，而粗壮傍人和人属具有衍生特征状态。最后，值得注意的是汤恩幼儿并未表现出粗壮的特征。
