Newborn Size and Pelvic Dimensions of Australopithecus

@article{Leutenegger1972NewbornSA,
  title={Newborn Size and Pelvic Dimensions of Australopithecus},
  author={W. Leutenegger},
  journal={Nature},
  year={1972},
  volume={240},
  pages={568-569}
}
IN mammals construction of the pelvis not only reflects functional adaptations to certain modes of locomotion but also depends on maternal-foetal size relationships. Therefore, information about body weight and head size of newborn Australopithecus in relation to the size of the female pelvic inlet is of evolutionary significance with respect to the adaptation of hominids to bipedalism. 
Functional aspects of pelvic morphology in simian Primates
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An estimate of the degree and interaction of selective forces acting on the pelvis of simian Primates which result from maternal-fetal size relationships and their interaction with selective forces resulting from locomotory functions in Australopithecus africanus is given to further elucidate the problem of the evolution of hominid bipedalism. Expand
Some implications of relative biomechanical neck length in hominid femora
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Fossil hominids through the middle Pleistocene appear to have relatively longer femur necks than expected, excepting the two small australopithecine females, and it is suggested that this variation results from smaller crania at birth in the fossils. Expand
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The aim of this paper is to present results of a new morphometric analysis of australopithecine pelvic bones to try to understand the reasons of this situation, it appears that australipithecines exhibit the same overall architectural pattern as extant humans, the hominid pattern, just as all African apes also exhibit thesame pongid pattern. Expand
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The scaling of neonatal size in eutherian mammals and primates in particular is investigated and it is demonstrated that neonatal weight in 15 species of anthropoid primates scales at a power of maternal weight of 0.70. Expand
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It is argued that (1) the chimpanzee model is no longer tenable, and (2) they also would have been smaller than corresponding female pelvic dimensions, i.e. obstetrical constraints were absent in Pliocene hominids. Expand
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A Homo-like obstetrical mechanism for Australopithecus, characterized by the rotation and the flexion of the Neonate, with fetal skull size similar to the one of the neonate chimpanzee, in the pelvic cavity is suggested. Expand
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Early Hominid Postcrania and Locomotor Adaptations
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TLDR
Although the postcranium of Australopithecus africanus is uniquely different from all extant hominoids, it is nearly identical to A. afarensis, which implies that natural selection was maintaining a structural adaptation for locomotor behaviors unlike those seen in any extant Hominoids. Expand
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