[CH] knuckledragging ancestors
Marc Norman (Marc.Norman@utas.edu.au)
Fri, 24 Mar 2000 13:59:27 +1100
ok all you self-avowed knuckledraggers, your ancestry is revealed.
Evidence that humans evolved from a knuckle-walking ancestor
BRIAN G. RICHMOND AND DAVID S. STRAIT
Nature 404, 382 - 385 (2000) © Macmillan Publishers Ltd.
Bipedalism has traditionally been regarded as the fundamental adaptation
that sets hominids apart from other primates. Fossil evidence demonstrates
that by 4.1 million years ago, and perhaps earlier, hominids exhibited
adaptations to bipedal walking. At present, however, the fossil record
offers little information about the origin of bipedalism, and despite
nearly a century of research on existing fossils and comparative anatomy,
there is still no consensus concerning the mode of locomotion that preceded
bipedalism. Here we present evidence that fossils attributed to
Australopithecus anamensis (KNM-ER 20419) and A. afarensis (AL 288-1)
retain specialized wrist morphology associated with knuckle-walking. This
distal radial morphology differs from that of later hominids and
non-knuckle-walking anthropoid primates, suggesting that knuckle-walking is
a derived feature of the African ape and human clade. This removes key
morphological evidence for a Pan-Gorilla clade and suggests that bipedal
hominids evolved from a knuckle-walking ancestor that was already partly
terrestrial.
(and partly extra-terrestrial?)
more on topic, were there any native chiles in Africa 4 million years ago?