Re: Savanna: a slow demise

Phil Nicholls (pnich@globalone.net)
Mon, 02 Oct 1995 15:07:00 GMT

clarke@acme.ist.ucf.edu (Thomas Clarke) graced us with the following
words:

>In article <4463oo$5hj@news.global1.net> pnich@globalone.net (Phil Nicholls)
>writes:

>> First of all, that early hominids occupied savanna
>> habitats is not a theory. It is a fact.

>Is it? Where have the fossils been found?

Early hominid fossils are found East Africa and Southern Africa.
Paleoclimatological evidence shows them to be associated with savanna
habitats. This really is not an issue, even for the AAH people.

>>> I have a very simple standard that I believe all scientist use
>> -- evidence. Show me the evidence.

>As a person of theoretical bent, who likes to read cosmology.
>I resent that. You imply that my interest is not scientific.

If you are constructing your theories without evidence then you are
engaging in groundless speculation and they are not theories at all.
Most people I know with an interest in cosmology base there
speculations on the available evidence.

>> Fact: Pre-hominids were forest dwellers
>> Fact: Early hominids were savanna dwellers

>As, I asked. is this a fact? Don't forget the 1-2 MY gap
>in the record.

Yes, it is a fact and again this is not in dispute. What is in
dispute is the side trip into the aquatic environment proposed by the
AAH supporters and for which there is no evidence. A gap is not
evidence.

>> The transition is critical.

>Yes indeed. If all that is required for a knuckle walking to
>bipedal transition is an ape and a forest margin, they why is not
>the world today full of many bipdal ape species?

First of all we are fairly certain that the common ancestor of modern
apes and humans was not a knuckle-walker. It is very likely that
knuckle-walking developed after the hominid-pongid split.

The second part of your question makes no evolutionary sense
whatsoever.

>> I believe it took place in the zone at
>> which forests border on savannas. This is because some of the
>> earliest hominids clearly retained arboreal adaptations. It makes a
>> great deal of sense.

>Point of logic: the retention of arboreal adaptations does not imply an
>arboreal life style. An arboreal foot with a little webbing could
>serve an aquatic/wading life style very well - but I stretch the evidence
>as you do.

Arboreal adaptations do indicate an arboreal lifestyle unless you have
EVIDENCE to indicate otherwise. It is not a stretch to note the
curvature of the hand bones in A. afarensis and the intermembrial
index and compare it w ith living arboreal apes.

>> Therefore, even if we find the fossils of such apes we have
>> no way to know they are aquatic apes.
>
>> So you see, this is not just posturing about definitions and words.

>Them's fighting words in cosmological circles. Just because
>the transition from a unified force to the seperate strong and
>electroweak forces as the universe cooled a few seconds after the big
>bang is not directly observable and leaves nothing in the way of
>unambiguous signatures in element abundances etc, are you saying
>that discussions of this event are not science, are just posturing
>about definitions and words?

No, that is not what I said at all. Please notice the "not" before
the words "just posturing."

>Tom Clarke

Phil Nicholls pnich@globalone.net
"To ask a question you must first know most of the answer"
-Robert Sheckley