Re: Large animal extinctions caused by early man
Bob Keeter (b_keeter@owens.ridgecrest.ca.us)
Wed, 10 Jul 1996 02:49:28 GMT
I have to agree with most of what you said. Any people that made it to
the New World via Siberia and Berengia would definitely not fit into the
modern "98-lb weakling" category. I suspect that like pioneering people
of every era, these
were the tough and rugged fringe of what was already a very
survival oriented society. I am also quite certain that
they had no reservations about killing every last horse,
camel, mammoth or mastodon if it ment food at the campfire!
At the same time, I have to wonder about a few "facts".
First, if we are to accept the Clovis dating and those
of some of the more credible pre-Clovis sites, it pushes
human habitation right to the very end of the last real
ice age and opening of the Bering land bridge. Even if
we assume that these hearty adventurers sprinted across
the land bridge, down the west coast of North and South
America, they did not really have "a few centuries" to
do their dirty deed of wiping out all of the big, fattened,
but comatose megafauna!
As for Occams Razor, some of the simplest explainations
might be:
1. Some force connected with human habitation or migration
also led to megafauna extinction (this is in essence the
climatic theory)
2. Some form of old world disease(s), applicable to the
local megafauna trashed all of the different species.
3. Men ate everything bigger than a modern bison! (or at
least killed enough to destroy the reproductive vigor)
4. Martians turned them into SPAM (i.e. the canned variety).
5. A combination of all of the above.
6. None of the above.
Please add others if you have a compelling urge!
Unless I misunderstand Occams Razor, the idea is to choose
the simplest explaination for a phenomena that is not
contradicted by fact nor so improbable as to be ridiculous.
If I start with my short list, lets thow out #4 (I havent
seen Independence Day yet, so forgive me my cynicism!).
Got real problems with #2 as well. If the disease, and I
could imagine something like modern anthrax which is not
really species dependent, came streaming over from Siberia
with a handfull of immune/resistant creatures, where are
the decendents? Also if the Asian relatives of the New
World megafauna had coexisted with this strain of disease
and acquired immunity to the bug, where did they go? Now
we have to hypothesize another bug making the trip from New
World to Old. That is not an entirely unlikely event, but
we need to have not just _any_ disease, we need one virilent
enought to totally decimate a population of Asiatic megafauna
that was at least as "toughened" as the humans that made the
trip to Alaska! Sort of does not sound right from a
probs & stats point of view. Drop the Razor on this one!
Man's appatite is well known along with his ability to excess;
(Please no cries of social conciousness!), but it takes
time for things to happen. It took the better part of
300 years for European man to spread from the east and
west coasts of North America to the middle of the continent.
This is with a steady influx of immigrants, modern innovations
such as beasts of burden, steam ships and trains! On bare
foot, could nomadic bands have done the same (while
simultaneously stopping long enough to have 10-child families
and exterminate every mammoth in sight?) Unless I am mistaken
most, recent nomadic bands tended to move when required or
when customary, but really didnt move their range of
influence unless forced to do so by environmental pressure
or more belligerant nomads! Stepping into this buffet of
food on the hoof, there would have been little need for a
wandering band to move on until forced to by the season,
migratory food animals or population pressure. Seasonal pressure moves
the population generally north and south,
following heards. Population pressure pushes out in all
directions, but requires time (centuries you said?) to start.
Long odds here again my friend.
Leaves me with #1, #3, and #5. Just because, I want to keep
#5 as an option. I dont think that we KNOW a lot about the
causes. Until we do, one guess may be better than another, but
both are just guesses!
As for #1, the climatic change obviously would have effected
local populations. Lakes dry up and fish die. An ice sheet
in Utah disappears and the cold-loving mammoths of California
die (or do they just move to Oregon, BC and Alaska? Remember
these are big, long legged "survival oriented" animals.) They
stand and die in the 100 deg heat of the Mohave or move north.
Furthermore the climatic change would have to be just as
drastic in Europe and northern Asia as in the Americas. Dont
know of any weather pattern that would have hammered the
megafauna of Europe, Asia, North and South America and have
spared Africa!
Having eliminated everything except a sentimental attachment
to #5, let me offer another option. As I see it there is no
other explaination than that a tribe of elephant-killing African
pygmies were abducted by flying saucers, deposited in Kansas
whereupon the proceeded to nail all of the mega-herds of
megafauna with their poisoned arrows! OK, a bit far fetched,
but we do have the dear ole Razor again!
Could be, might be, ITS TRUE! #5 is the winner and still champ!
We dont know the answers. Some of the theories look quite a bit
better than my new Pygmy hypothesis, 8-))), and few are really worth
ridicule! If I remember, the "ether" and "phlogiston" were all
supported by learned men of their times. May be that there is
something stil to learn here as well!
Sorry boss, this here ole country boy just aint so sure 'bout
none o those high faluting theries! So i'll jes lay back here
on this ole stump and throw mule muffins at the whole lot of em!
I wont even leave the newsgroup if someone laughs at my comments!
Well maybee on second thought, a few snickers might be OK as long
as it doesnt transmute into a guffaw! 8-/
Regards
bk
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