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More response to Elaine Morgan...
Ralph L Holloway (rlh2@columbia.edu)
Wed, 19 Jul 1995 00:12:25 -0400
Dear Elaine,
This is the beginning of what may be a long set of communications.
This particular one is not very intense and not very long, nor in very
much depth. I've corrected my outlook on your AAH, and have decided to
take you very seriously indeed. Consequently, I have read most of your
two books, "Scars of Evolution" and "The Aquatic Ape". I should finish
them in a day or so.
I'd like to make some observations. First, I like the way you write.
It is clear, has humor, and is entirely engaging. I does have facts and
interpretations, and you have been making very serious efforts at synthesis.
Secondly, I still believe that there are serious contradictions in your
understanding of evolutionary theory and how you apply it to the problems
of the fossil record, behavior of living animals and the
paleontolotgical past. I will try to enlarge on that criticism somewhat
later.
Third, as I explained in a previous post, I came to AAH through Sci.
anthropology. paleo, and thus many of my reactions were to the exchanges
I encountered between Mr. Dooley, Mr. Troy, Phil Nichols, J. Moore, Alex
Duncan, etc., etc. Myt only point here is that I believe Mr. Dooley and
Mr. Troy have pretty accurately characterized most of the major points
of your hypothesis, and that the "detractors" have also fairly
characterized your position and offered illuminative critiques of some of
sequelae of your hypothesis (e.g., tears, fat, predation, fossil record,
heat dissipation, etc.), some of which have involved useful research
(without playing favorites I might mention the innervation of the
lacrimal glands, composition of tear, and yes, the crocodile information,
which I certainly never found "tedious"). I was very worried that in fact by
paying so much attention to these
fragments I might have been quite in error in not going directly to the
source ( and I thank you for providing Hardy's comments in the Appendices
of the AA book). I find that I am not that much in error, but do regret
that I hadn't done the proper thing which is always to consult the
original and not second hand attempts. I don't blamed you for being
pissed off at me, and publicly apologise.
Let me start with page 1 of "Scars...". You mention that the sheer
resemblance between ourselves and the African apes suggested to Darwin
that we share a common ancestry. You then say that "...this solution
immediately raised a further problem. If we are so closely related to
them-and everything we have learned since suggests that the relationship
is even closer than Darwin-supposed-then why are we not more like them?"
You might as well ask why we are not identical to each other. The
differences strike some as enormous and others as minimal. The molecular
genetic evidence suggests about 1% between ourselves and chimpanzee, and
only slightly more between ourselves and gorilla. Ah, but that one %? It
seems most likely that regulatory (rather than structural ones) genes will
eventually be identified to
explain differences in growth rates, durations, initiations and
cessations of various cell lines, etc, that will account for almost all
of the minor morphological differences we see. The game is still on to
really demonstrate true physiological differences between ourselves and
the great apes. Chimpanzees have been observed to weep over lost
relatives, and Gorillas have been observed to sweat.
You go on to say "... When a species splits and gives rise to three
separate lineages, there is no reason to expect that species C will
differ from A and B any more widely than A and B differ from one another.
Yet in the case of the anthropoids this is what happened..."
GG Simpson, the paleontologist has some excellent discussions of
morphological differences in one of Washburn's edition volumes that the
Wenner -Gren published (I think it is the one on Classification). It is
worth reading, because I know of none
trained in paleontology who would make the claim you have. Speciation is
something that happens between populations because they are usually
confronted by different environments and are most often faced with some
barrier, usually geographic, to gene flow. It is perfectly reasonable to
expect that the total conditions faced by C might be quite different that
those faced by A and B. Remember, evolution is opportunistic, and without
a fossil record for chmpanzee and gorilla, we cannot hope to know whether
the deparation as between Aand B to C was a truly punctuated event,
whereas between A and B, the punctuation was less manifest. At least
consider random genetic drift as a partial evolutionary force in this
A,B, C scenario, and there might be very good reasons why the differences
between A,B,C are not uniform.
In essence, although you don't mean it so, you statement on page 3
that: "...the essential point is that evolution takes place in response to
things which have happened (italics yours), not things which are
predestined to happen. Man is no more an evolutionary pinnacle than a
tree is, or a termite or an octupus. His emergence was no more inevitable
than that of any other species." This is surely correct, but it flies in
the face of what you previously said, and what follows below:
"The present state of play may be summarised as follows. Four of the
most outstanding mysteries about humans are: (1) why they walk on two
legs? (2) why have they lost their fur? (3) why have they developed such
large brains? (4) why did they learn to speak?
The Orthodox answers to these questions..." you say, is "we do not
yet know..."
The problem for me is that you so overstress the differences as to
almost make them of a quantum nature. I don't see chimpas and gorillas as
furry. I see them having more hair than we do. Humans haven't lost their
"fur" (please, hair), there is less of it, which incidentally varies
widely among different human groups, and in which case, to be true to
your logic, would involves various dregrees of an aquatic adaptation in
different human groups...I don't see the
differences between ape locomotion and our own as something more than
modifications of existing anatomy and neurological and
neuromuscular integration that makes bipedalism
a quantum leap from knuckle-walking, or as something so incredibly
different that it required evolutionary nourishment in an aquatic medium
for a couple of million of years. More to the point, it is arguable if we
can ever "know" in the sense you might have meant "we do not know yet",
but some of the alternative hypotheses out there do actually suggest
reasons 'why', such as the standard savannah standard theory, or some of
Wheeler's ideas regarding heat loss, sweating, hair, etc.
In sum, I am not convinced that you always apply the same standards
to your ideas regarding evolutionary dynamics that you apply to others.
This is very striking to me when I read ytour statement regarding the
savannah theory on page 8: "One serious weakness in the savannah theory
lies in the disproportion between the commonplace event it depicts and
the spectacular consequences alleged to have flowed from it. Many primate
species such as baboons and vervet monkeys and patas monkeys have left
the trees to live on the savannah. They have lived there quite as long as
your ancestors ever did, YET THEY SHOW NO SIGNS OF ACQUIRING ANY
HUMAN-LIKE FEATURES SUCH AS HAIRLESSNESS OR BIPEDALISM (emphasis mine)".
This expectation flies in the face of all of your previous 7-8 pages of
references to evolutionary theory. You expect species in different
superfamilies to give the same adaptive response to the same environment?
I thought you said evolution works on the genetic materials at hand...Why
these monkeys, who incidentally are never far from trees, or in the case
od baboons, acacia thorn trees, should develop the same adaptations as
the human animal based on what I know of evolutionary theory and genetics
is totally beyond my understanding. It is like expecting all sea animals
to be morphological the same. They aren't.
So there is my initial reaction to your first hand first chapter in
"Scars..." I still believe that the anatomical and physiological details
that create "problems" for standard scenarios are far overblown and that you
are selectively using evolutionary paradigms to suit your purposes.
If I have duplicated some previous discussions of earlier AAH
threads that I have't seen, forgive me. More will come.
Ralph Holloway.
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