Re: An alternative to ST and AAT
Roger Dodger (rogerdodger@triax.com)
20 Nov 96 12:01:46 -700
Roger Dodger has this to say about that-
>In article <56sgt5$9kv@news.NL.net>
> G.Hanenburg@inter.nl.net "Gerrit Hanenburg" writes:
>> Paul@crowleyp.demon.co.uk (Paul Crowley) wrote:
>>
>> >But any serious thought on Lucy's morphology should lead to
>> >the same conclusion. If you can't stride, you must waddle.
>>
>Striding, in this sense, rules out waddling, which as you say,
>involves excessive lateral displacement. Chimpanzees and gorillas
>cannot stride when they walk bipedally; nor could Lucy or male
>A.afarensis. Surely the development of the bipedal stride was
>the major change with H.erectus morphology?
>> Both Lucy and modern humans have what is called striding bipedalism.
>> Striding bipedalism refers to the kind of locomotion in which the body
>> is supported by first one leg and then the other,and as the body
>> passes over the supporting leg,the other leg swings forward in
>> preparation for the next support fase. During transfer of the body
>> from the trailing to the leading leg there is a brief period when both
>> feet are on the ground.
>I cannot see how you would distinguish "striding bipedalism"
>from "non-striding bipedalism" under your description.
Seems to me that this argument has been settled by the discovery of
the footprints in volcanic ash near Hadar(?), and dated to around the time of
both Lucy and H. habilis (2-2.5 MYBP ?). Please excuse the question marks, I
don't have any of my references handy for exact place and time.
These footprints show without a doubt that the creatures that made them (Lucy
or H. habilis) had a definate 'striding' style of locomotion. The twisting of
the front (or ball) of the foot, inherant with an ape 'waddle', is non-existant
in these prints. The prints definatly show a 'one-foot-in-front-of-the-other'
stride. What makes these prints so interesting is that there are prints of
TWO individuals walking side-by-side.
I also remember that Lucy's Pelvis and Femur, as well as the angles of the knee
joint show that Lucy had a nearl H. habilis shows the same traits.
Ergo, the bi-pedal striding-style of these two beings, obviously had to be
developed in a creature yet to be found.
Roger Dodger
from the City-State of the Invincible Overlord
I always get the fuzzy end of the lollipop.
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