[escepticos] Evolucion humana

["Ramón Díaz-Alersi" <rda@...>]

Dedicado a mi amigo y "adversario" Ernesto, a ver si se anima a escribir:

Del Nature de ayer:

Evidence that humans evolved from a knuckle-walking
ancestor
BRIAN G. RICHMOND AND DAVID S. STRAIT
Department of Anthropology, The George Washington University, 2110 G Street,
NW, Washington, DC 20052, USA

Correspondence and requests for materials should be addressed to B.G.R.
(e-mail: brich en gwu.edu)


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 ago1, and perhaps earlier2, 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
bipedalism3-10. Here we present evidence that fossils attributed to
Australopithecus anamensis (KNM-ER 20419)11 and A. afarensis (AL 288-1)12
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.

Nada, que cada vez está más claro que somos monos :-)

RDA