Re: Speciation - how do you know?
HARRY R. ERWIN (herwin@mason2.gmu.edu)
10 Sep 1996 15:10:17 GMT
Yousuf Khan (ykhan@achilles.net) wrote:
: On Fri, 6 Sep 1996 12:36:59 GMT, tedwards@DialUp.FranceNet.fr (Tim Edwards
: and/or Marghie Parsons) wrote:
: >In paleoanthropology, how do researchers determine that one creature
: >is not the same species as another? Am I correct in my understanding
: >that the question is still open vis-a-vis modern humans and
: >Neanderthals? Is it pretty much accepted that Homo Erectus was a
: >separate species?
: No, they are not even certain that even Homo Erectus was a separate species
: yet.
: If you look at the bodies (below the neck) of modern man, neanderthals, and
: erectuses, they are identical. The only difference is in the shape of the
: skull. Even within the skull, you find many features like the inner ear
: cavity among other things that are completely identical between them all.
Er, no. The best remains of H. erectus, the Nariokotome boy, dating to
about 1.7 MYr BP, have a number of features in the spine, ribcage, and
pelvis that are distinctly non-modern. The spinal cord channel was small,
the ribcage was conical (adapted to climbing), and the pelvis had a number
of differences in morphology that suggest slightly less specialization for
large-brained babies. H. neanderthalensis had a number of skeletal
specializations for close-in combat with large mammals that goes far
beyond anything seen in American football today.
--
Harry Erwin, Internet: herwin@gmu.edu, Web Page: http://osf1.gmu.edu/~herwin
49 year old PhD student in computational neuroscience ("how bats do it" 8)
and lecturer for CS 211 (data structures and advanced C++)
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