quote:
I'm also sure you are familiar with the computer simulations by Robin Crompton?
Are you? If you are, then please share it here (if possible & legal). I've been trying to get them.
Anyway, if you are aware of Robin Crompton then I am also positive that you knew that Crompton said this...
J Hum Evol. 1998 Jul;35(1):55-74. Related Articles, Links
The mechanical effectiveness of erect and "bent-hip, bent-knee" bipedal walking in Australopithecus afarensis.
Crompton RH, Yu L, Weijie W, Gunther M, Savage R.
Department of Human Anatomy and Cell Biology, University of Liverpool. rhcromp@liv.ac.uk
It is universally accepted that the postcranial skeleton of the early hominid Australopithecus afarensis shows adaptations, or at least exaptations, towards bipedalism. However, there continues to be a debate concerning the likely form of terrestrial bipedality: whether gait was erect, like our own, or "bent-hip, bent-knee" like the bipedalism of living chimpanzees. In this study we use predictive dynamic modelling to assess the mechanical effectiveness of AL-288-1 under both hypotheses, on the basis of data on segment proportions from the literature. AL-288-1's proportions are incompatible with the kinematics of chimpanzee bipedalism, but compatible with the kinematics of either erect or "bent-hip, bent-knee" human gait. In the latter case, neither the ankle nor the knee joint would have contributed substantial mechanical work to propulsion of the body, and net energy absorption is predicted for these joints, which would have resulted in increased heat load. Such an ineffective gait is unlikely to have lead to selection for "bipedal" features in the postcranial skeleton.
PMID: 9680467 [PubMed - indexed for MEDLINE]
So what are you trying to tell us concerning Crompton's animation?
This message has been edited by Andya Primanda, 08-19-2004 03:25 AM