Re: Large animal extinctions caused by early man
Karen (karen@uab.edu)
Mon, 01 Jul 1996 22:41:29 GMT
p3voices <p3voices@earthlink.net> wrote:
>:In article <31D1F591.58B0@earthlink.net>, p3voices
>:<p3voices@earthlink.net> says:
>:>
>:>I was just trying to compile a list of large animals whose extinctions
>:could be
>:>the result to a significant extent the predations of early man. I
>:>believe a reasonable case could be made for the following man-driven
>:>extinctions:
>:>wooly mammoth
>:<SNIP>
>:----
>:From: timo.niroma@tilmari.pp.fi (Timo Niroma)
>:says::
>:Brian Fagan has in his "People of the Earth":
>:"In the northern latitudes of both Old World and New at the end of the
>:Pleistocene, many big-game species became extinct, but nowhere were the
>:extinctions so drastic as in the Americas. <SNIP>
>:How many paleo-Indians were there 12600 year ago? I think there were
>:so few men and so much big animals,
Is there evidence to support the contention that there were so few men
and so many big animals 12,600 years ago in the Americas?
that it is very difficult to
>:imagine that they could have been capable of doing anything like that
>:in the short time the extinction happened. And what weapons did they
>:have at that time to do such a deed?
There are also other factors involved in extinctions besides hunting.
Human culture has had profound effects on other populations, effects
that have nothing to do with hunting. This should be considered too.
>:Timo Niroma says:: <SNIP> My pet theory says that it was an
>:allright catastrophe caused by an asteroid or a comet hitting the
>:Northern Atlantic. There is no direct evidence for this, but all that
>:happened 12600 years ago, hints at that direction.
What happened 12,600 years ago that hints at that direction? If there
is no direct evidence for it, why is it your theory?
>:<SNIP> The latest investigations imply that
>:both Greenland and Antarctis were warmed by twice that amount in a few
>:years 12600 years ago. That if anything would have caused extinctions
>:in northern America and northern Europe.
As far as i am aware, the geological record does not show any major
flood in the americas from 12,600 years ago. If there had been a
major flood causing massive extinctions in North America, wouldn't it
have caused human extinction as well?
And it renders my catastrophe
>:theory still more plausible, because I don't know any other pattern
>:that can cause such a high increase in temperature in such a short
>:time.
WHen you say such a high increase in temperature in such a short time,
exactly what increase in temperature are you talking about and exactly
how short a time are you talking about? How does this make your idea
more plausible?
>:<SNIP>It is tempting to explain mass extinctions by finding unique and
>:irresistible agents that clearly are not part of the ordinary ebb and
>:flow of biotic change on earth.
Yet that is what it sounds like you have done. A catastrophe is a
unique agent when it is so great that it causes mass extinction.
For example, in the case of the
>:Cretaceous-boundary extinctions, the possibility of extraterrestrial
>:bodies catastrophically impacting the earth has been eagerly accepted
>:by some scholars as a robust explanation for the sudden disappearance
>:of so many dinosaur species.
You say that the impact theory for the extinction of the dinosaurs has
been eagerly accepted but this is misleading since for at least ten
years, paleontologists scoffed at the Alvarez theory. It was only
accepted gradually as the evidence came in and was studied and
researched and re-studied again and again. The evidence was only
accepted after stringent testing. One of the reasons it was so hard
to accept at first is that scientists are aware of how easily tempting
it is to use some colossal catastrophic event to explain a great
number of things. Most paleontologists as well as other evolution
scientists therefore are wary of such ideas. The Alvarez theory has
evidence to support it. First the irridium layer, the crater from the
impact was found, and the shock evidence of rocks have been found too.
In the case of the Pleistocene/Holocene
>:extinctions, every empirical comparison I can make between my
>:actualistic data and the fossil data seem to provide support for the
>:die-off scenario rather than for the kill-of scenario, therefore making
>:Clovis hunting unnecessary to explain extinction."
Again, hunting is not the only thing that humans have done to cause
extinctions. What is your actualistic data and what is your fossil
data? If you really have some evidence, you should share it.
>:I argued this thing in January in the sci.arhaeology group, but left
>:the debate, when it began to be a fruitless yes-no debate <SNIP>I think my
>:hypothesis gains more credibility.
I would be glad to listen to the evidence for your hypothesis and give
it credit, but haven't seen what it is yet. Admittedly, I couldn't
for some reason, find your original posting on this so I may have
missed what the empirical evidence that you claim is. If so, would
you please send it to me? Thanks.
Besides there are many examples of the
>:animals dying in heaps as if a great tsunami had thrown them and also of
>:animals that had collapsed on their straight feet as if they had caught by
>:a sudden tremendous heat.
A lot of animals die standing up, they just fall to the ground dead.
Is there something else that shows that they died in "heaps"?
>:<SNIP
>:Timo
>:+++++++++++++
>:p3voices replies:
>:Timo, sorry for all the snips, but I had to make a point....
>:First, your (and Brian Fagan's) hypothesis IS UTTERLY ABSURB!
To p3voices: I wish I had seen the original post of this because the
only quote I saw of Fagan's was not absurd and actually Fagan is known
to be pretty straight forward. I would like to see what the rest of
the issue is that you find absurd. Did Fagan really make this
hypothesis about great catastrophic events or was that just Timo using
Fagan out of context? It would be hard for me to imagine Fagan
proposing a great and convenient catastrophe on this subject.
>:Back to the original hypothesis of man's role:
>:It is certianly within the realm of possibility that early man's hunting
>:weakened the survivability of N.American large fauna, causing some
>:extinctions. Early man at this time had a good, lethal stone age weapons
>:technology. These large animals sure must have been tempting targets!
>:But, as you and others point out, they did not have a very large
>:population. Still, give enough time, focussed hunting on these animals
>:could have contributed to their decline. Maybe climatic changes also
>:played a role in this. Who knows for sure?
Again, is there direct evidence to support that at 12 kya, there were
great amounts of these animal populations and small human populations?
Giraffe's do not have a great population in the Kalahari of Africa and
neither do the humans that live there. The Kalahari is not able to
support large populations of either animal. The giraffe's are all but
extinct nonetheless from the nomadic hunters (the !Kung).
>:After all, consider what damage man, equipped with only stone weapons, did
>:when he first landed on New Zealand, Hawaii, or Madagascar. Shortly after
>:man's colonization of these islands most of the large fauna were hunted to
>:extiinction. Now, of course it is easier to kill off all of a species on
>:a (large) island than a continent. However this makes the point that man
>:could have played a role in other extinction events. Maybe man's role in
>:these extinction events was insiginificant; maybe not; new data will have
>:to be uncovered to prove this point one way or the other. It does serve
>:(as I thought it would) a beginning to an interesting discussion flow.
Again, cultural events play significant roles in extinctions too. It
is one of the biggest problems in primate conservation today. It is
not merely a matter of monkeys being hunted, but their habitat is
shrinking due to human primates. And there are a wide range of other
human culture based problems that are killing off the populations.
Just keep in mind that human interference is not limited to
intentional killing of populations.
P3... wrote this to Timo:
>:--> Back to your "extraterrestrial bodies catastrophe" theory killing the
>:N.American Pleistocene large fauna: It's so absurd that it hardly
>:deserves rebuttal. WHERE'S THE IMPACT CRATER? WHERE'S THE SHOCK-DAMAGED
>:ROCK'S? WHERE'S THE ASHFALL/DEPOSITS/WAVE/IMPACT DEBRIS DEPOSITS?
>:(enough caps) Where's the corollary extinction events among smaller
>:animal & plant fauna..etc...etc??
I agree with P3 that your idea needs supportive data. And if there
was some huge crash wave Tsunami style, why would the big animals not
survive, but the smaller bipedal ones survive?
--
Karen
>:P3
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