Re: An alternative to ST and AAT
John Waters (jdwaters@dircon.co.uk)
17 Nov 1996 12:33:37 GMT
Susan S. Chin <susansf@netcom.com> wrote in article
<susansfE0zz44.K7I@netcom.com>...
>
> : JW: I cannot site any source or references in respect
of
> : early Australopithicenes, and I doubt if anyone else
can
> : either. I say this because the really early
> : Australopithicene fossils only comprise teeth and
jawbones.
> : As far as middle Australopithicenes are concerned (e.g.
> : Lucy), my references are pretty ancient, but as far as
I am
> : aware they have not yet been seriously contradicted.
>
> Actually, A. anamensis does have a proximal tibia
preserved which show
> a bipedally-adapted anatomy. This early Australopithecine
species is
> dated at 3.8-4.2myo making it the earliest known hominid
(at the moment).
JW: The Australopithicenes I was referring to may not be
officially classified as australopithicenes.
Embarrassingly, I have lost the original data on this. No
doubt it will turn up when I need it the least. The first
*australopithicene* referred to consists of a single molar,
dated at 5.5 Myr. The second consists of a jawbone, dated
at 4.9 Myrs (from memory). If anybody can put official
references to these fossils, I'd be extremely grateful.
> : Jolly and Plog determined that Lucy's walking resembled
> : more of _a pigeon toed and lurching gait_. Perhaps this
is
> : where Paul got his idea of a waddling Lucy.
>
> I'd be interested to know on what basis they came to this
pigeon toed
> lurching biped conclusion. It is also interesting to note
that Jolly
> is a Primatologist while Plog's specialty is Archeology.
>
> On the other side of the bipedalism story, C. Owen
Lovejoy, who
> reconstructed the Lucy pelvis (flattened and distorted
taphonomically),
> calls Lucy a fully functional biped. She may not be as
efficient or
> elegant a strider as later hominids, but neither did she
struggle in her
> bipedal locomotion. I'd like to hear what those who think
otherwise
> explain the evidence of afarensis' bipedal gait from the
Laetoli footprints.
> The same evidence (pelvis, knee joint) can be interpreted
differently by
> various investigators. In this instance, I'd put more
stock in a
> specialist in hominid biomechanics and locomotion such as
Lovejoy.
JW: C. Owen Lovejoy, eh? Ummm. The so-called facts on of
his human evolution theory suggest a man who hasn't really
done his homework. Still full marks to the guy for daring
to put forward a hypothesis. Most professionals prefer to
sit on the fence.
However, you are quite right about the differing views of
the so called experts. How much faith can we have in the
view of Richard Leakey who maintained that Lucy could walk,
but could not run?
> : The part of the Australopithicene anatomy which is most
> : likely to make them less efficient is the heel. Modern
> : humans gain their bipedal efficiency from the ligaments
of
> : the lower leg which attach to the ankle via the
achilles
> : tendon.
>
> Is this what Jolly and Plog state in their 1987 textbook?
JW: I don't know, since I haven't read their book.
The statement is mine. I don't know whether the
austalopithicenes bipedalism was less efficient. My
comments are based upon the statements of the professionals
who have described the Lucy anatomy. In this context, they
say that the part of the leg above the ankle is relatively
modern, but that the foot is primitive.
I assumed (perhaps wrongly) that the word primitive
indicated an anthropoidal anatomy. This view would be
supported by the statement that the femur etc., was very
dense, implying that the leg was strongly muscled like that
of an ape.
As you know, the Laetoli footprints indicate that most of
the weight was placed on the outer edge of the foot. If the
individuals were not bowlegged, this suggests that the
lurching gait described by Jolly & Plog might have some
substance to it.
That said, (speaking as a man who doesn't know a tendon
from a toenail), I am as dependent as the next person on
the heuristic evidence provided by the professional
scientists. If the professionals disagree on the
interpretation of hominid bipedal abilities, I wouldn't
disqualify a person on the grounds that they were a
primatologist, or even an archaeologist. After all hominds
are primates, are they not? And Archaeologists specialise
in scientific reconstructions.
What do you make of the evidence? A climber/walker, or a
walker/runner? I would be interested to hear your views on
this. Also, do you think a bipedal female would have any
special difficulty in carrying dependent infants?
John.
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