Crowley posts again
Alex Duncan (aduncan@mail.utexas.edu)
16 Nov 1995 16:13:24 GMT
Well, Paul posted another one to sci.bio.evolution. Paul, are hoping
that you can post there, and I won't see it, and your inane arguments
will go unanswered? Anyway, here's Paul's latest from the other group,
and my response to it.
In article <48dvrl$bpn@nntp5.u.washington.edu> Paul Crowley,
Paul@crowleyp.demon.co.uk writes:
>> Other features, such as bipedalism, have an
>> evolutionary history that is well-documented by the fossil record. The
>> fossil record provides no evidence that bipedalism evolved in an aquatic
>> habitat.
>
>Does the fact that all hominid fossils are found in lacustrine deposits,
>and are never associated with chimps fossils, mean anything at all?
>
> . . . . . . Naaah.
All hominid fossils found in lacustrine deposits? Again, Crowley
demonstrates an appalling lack of information about the subject at hand.
I would guess the majority of hominid fossils are found in fluvial
deposits (certainly a large proportion of them are). Since most
depostion is associated w/ the action of water, and since most fossils of
terrestrial organisms are found in either lacustrine or fluvial deposits,
it would be a mistake of gargantuan proportions to make much of this
(Paul rushes in where angels fear to tread). (note: yes, I am aware that
fossils are also found in marine and occasionally in aeolian deposits.)
As far as the fact that hominid fossils are never found w/ chimp fossils
... so what? There aren't any chimp fossils.
>> > > - when hands are need to carry food.
>> > > - to obtain a better view of the surrounding area.
>> > > - jumping across small brooks
>> > > - treat displays.
>> > > - when watching an unusual part of the surroundings
>> > > - when locating another member of the group
>> > > - greeting and courtship displays.
>
>> The fact that Paul has produced this as his list leads to the suspicion
>> that, like most of the supporters of the AAT, he hasn't read much in the
>> way of "standard" paleoanthropology, and thus has no concrete idea what
>> it is that he's arguing against.
>
>It seems that Alex disapproves of "standard" paleoanthropology when it
>is quoted, without alteration, directly at him. It must be "standard"
>PA that "thus has no concrete idea of what it is . ."
Apologies then to Jim Moore and Phil Nichols, but this list is a flawed
oversimplification of the ideas put forward to account for the origin of
bipedalism. Again, if Paul were more (even vaguely...?) familiar with
the literature, he would know this.
>> >It does not know how our hominid ancestors survived two billion freezing
>> nights >on the African heartland, surrounded by lions, leopards and hyenas.
>>
>> These issues have been discussed repeatedly in s.a.p. Somehow the fact
>> that other primates are capable of doing exactly what Paul describes
>> above is not considered to be relevant.
>
>All other primates have quite specific adaptions and behaviour for
>obtaining safety at night - in particular four grasping limbs. Their
>infants also have four grasping limbs. So the chimp mother/infant
>dyad can make a nest in the branches where two trees meet and they
>can all hold on and get a good night's sleep.
>
>The hominid mother/infant dyad could *not* do this from at least
>3.6 mya (Lucy) and probably from 5mya. So where did they spend the
>nights? - No answer from PA.
Wrong. There is an answer from PA, but Paul doesn't like it. The
earliest hominids probably spent their evenings in the trees. They were
certainly capable of it. I have a lengthy response to Paul's claims
regarding Dr. Ohman in s.a.p., and urge anyone who wants to see it to go
there.
>Alex's "retained significant grasping capabilities of the hindlimb"
>comes from ignoring the Laetoli footprints at 3.5mya and a curious
>view of Lucy's few footbones. Alex was thoroughly shot down by Dr
>James Oman of John Hopkins Univ. Medical School
My "curious view" of the A. afarensis pedal remains is a view that (as
far as I can tell) is shared by the majority of the people who have ever
thought about the manner and had an opportunity to examine the casts or
fossils first hand. Contrary to Paul's suggestion, my view was not based
upon a view of "Lucy's footbones". Lucy's pedal skeleton consists of an
astragalus and a proximal pedal phalanx. My views are based upon
analysis of the AL 333-115 foot (associated metatarsals and proximal
phalanges), and other metatarsals and phalanges from the Hadar collection.
>Nevertheless he has now forgotten "that we all have our biases"; his bias
>has now slipped back into ineluctable fact:
>
>> Bipedal feet? Well... the earliest
>> hominids were bipedal, but they also retained significant grasping
>> capabilities of the hindlimb, and there are many other indications that
>> they were capable tree climbers.
The retention of grasping capacities in the Hadar pedal remains is about
as close to being "fact" as we can get in functional morphology.
Alex Duncan
Dept. of Anthropology
University of Texas at Austin
Austin, TX 78712-1086
512-471-4206
aduncan@mail.utexas.edu
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