Re: Lamarckist Contradiction

Susan S. Chin (susansf@netcom.com)
Sat, 23 Nov 1996 05:18:34 GMT

Rabbi Bruce Cohen (ravbar@mail.idt.net) wrote:
: A point I wish to raise in regard to postings like the one I just
: read. Even the most amateur of paleoarchaeologists knows that
: Larmarckism (the belief that the genetic material of a species can be
: altered by the external, non-radioactive, non-chemical influences of
: its enviromment, such as climatic changes), is false.

: So why are we getting discussion about climate changes producing
: changes in the pedal architecture of primates? Are there hidden
: Lamarckists among us? The fossil record does not justify at this point
: the conjecture that climate change somehow yielded a biped, because
: bipedalism would make for better scavengers than quardrapedal, or
: semi-erect ape-like locomotion. There are no transitional forms in the
: fossil record to make such conjecture justifible publicly, are there?

Okay, one more try at this one. I would have to agree that currently,
there isn't enough information to justify statements that bipedalism came
about because "freeing the hands for other uses was advantageous" or
"bipedalism was an adaptation of apes who left the forrest," and so on. I
think it's great that there are so many in this newsgroup, and elsewhere,
who are looking into this "mystery" of bipedalism, and why? I don't claim
to know why it happened, except that it did. And my semi-educated
guess would be that adaptations to a previously unexploited niche had
something to do with it, along with possible climatic and environmental
changes which required that early proto-hominids adapt, and adapt
fast, or face extinction, which likely happened for many early ape
species,lineages and possibly some early hominid species and lineages too.
Homo sapiens just happened to descend from ancestors that made it this
far. Looking at the recent finds of early hominid species, anamensis,
possibly ramidus, one has to wonder how many other early hominids are
still out there to be found...

But when you ask where the transitional forms are, it seems to me that
early Australopithecines are it, in many respects. Here we have bipeds
walking around with ape-like cranial, facial and dental features. A very
specialized adaptation in locomotion coupled with primitive craniofacial,
and dental traits. All the Australopithecine species display these traits
to some degree or other, from the material currently known. At least we
know that the first steps towards becoming human were literally steps.

Susan

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                                             susansf@netcom.com