[meteorite-list] What killed the woolly mammoth? A whole bunch ofthings

From: Sterling K. Webb <sterling_k_webb_at_meteoritecentral.com>
Date: Wed, 13 Jun 2012 01:47:25 -0500
Message-ID: <780FE6D021104923A862B2FF340E0179_at_ATARIENGINE2>

> What killed the woolly mammoth?

That's only a small part of the tangle of the
Proboscideans. The Woolly Mammoth evolved
from the Steppe Mammoth about 250,000 years
ago, and the Steppe Mammoth evolved from the
Ancestral Mammoths about 700,000 years ago.
The Ancestral Mammoths appear about 2.5-3.0
million years before that --- in Sub-Sarahan
Africa!

You have to admit Africa is a strange place for
Woolly Mammoths to trace their family tree from,
the Asian Elephants and Mammoths spitting
off at about the time.

The Mammoths are related to the Mastodons
who appear 28 million years ago and covered
every continent except Antarctica and Australia.
The South American Mastodons lasted until
9000 years ago, but North American Mastodons
(equally "woolly") died out about 12,000 years
ago, very like the Mammoths themselves.

The causes cannot be same, despite the fact
that the timeline is so similar, as Mammoths
and Mastodons have different diets, need
different terrain, environment, and climate,
but they disappeared together.... One thing
stands out, though: each successive Mammoth
species was smaller than the one before it,
ending with the Wrangel Mammoths who
are no longer considered "dwarf;" they were
about 2 meters at the shoulder. (Mediterranean
Dwarf Mammoths were tiny, about the size of
a Saint Bernard dog.)

Scores of genera of "giant" mammals vanished
from North America at the same time, with
nothing much in common except that a) they
were big, and b) there were suddenly humans
in the neighborhood.

The climate change argument is a poor one,
as the climate of North America had been cycling
through the usual changes of an Ice Age for some
millions of years. And Man The Mighty Hunter
doesn't convince me either. On the other hand,
Man The Massive Environmental Changer might
convince me, but there's no evidence of that in
North American 12,000 years ago.

Similar arguments have been raging about the
megafaunal extinctions in Australia, the theory
being that the massive environmental change
was caused by the human use of fire, not hunting.
That's been the big theory in Australia for decades,
but now chronometric cores say the megafauna
disappeared before fire increased, so they are back
to the Mighty Hunter theory.

See, they don't need a Dryas to generate lots of
controversy.

Poor Mammoths! Everything just ganged up on
them all at once, I guess. Is that the current
consensus? Did anyone ever considered that
mere Giantism itself could be a self-defeating
evolutionary strategy? In the long run, I mean.
Giantism has been around for hundreds of
millions of years, so there are lots of arguments
for what a good idea it is. I think that's because
we humans are always impressed by sheer
bigness (Jurassic Park Syndrome).

So why were the Mammoths "trying" to get
small? There are so many things a "giant" can't
do. It can't climb trees; it can't fly; it can't burrow;
it can't live in the hills -- it doesn't function well
in anything but flat terrain. There is a huge
"investment" in huge individuals and their
numbers are limited by that. Their range of
"livable" conditions is very narrow.

That's always a "giant" risk.


Sterling K. Webb
-----------------------------------------------------------
----- Original Message -----
From: "Paul H." <oxytropidoceras at cox.net>
To: <meteorite-list at meteoritecentral.com>
Sent: Tuesday, June 12, 2012 3:49 PM
Subject: [meteorite-list] What killed the woolly mammoth? A whole bunch
ofthings


> What killed the woolly mammoth? A whole bunch of things,
> scientists say, Christian Science Monitor, June 12, 2012,
> http://www.csmonitor.com/Science/2012/0612/What-killed-the-woolly-mammoth-A-whole-bunch-of-things-scientists-say.-video
>
> Woolly Mammoth Extinction Has Lessons for Modern
> Climate Change, ScienceDaily, June 12, 2012
> http://www.sciencedaily.com/releases/2012/06/120612144809.htm
>
> Many factors in extinction of mammoths, SBS,
> June 12, 2012,
> http://www.sbs.com.au/news/article/1658619/Many-factors-in-extinction-of-mammoths
>
> Study: Many factors in mammoth extinction, UPI.com, June 12, 2012
> http://www.upi.com/Science_News/2012/06/12/Study-Many-factors-in-mammoth-extinction/UPI-96671339529828/?spt=hs&or=sn
>
> The paper is:
>
> MacDonald, G. M., D. W. Beilman, Y. V. Kuzmin, L. A. Orlova, K. V.
> Kremenetski, B. Shapiro, R. K. Wayne, and B. Van Valkenburgh, 2012,
> Pattern of extinction of the woolly mammoth in Beringia.
> Nature Communications, 2012 DOI: 10.1038/ncomms1881
> http://www.nature.com/ncomms/journal/v3/n6/full/ncomms1881.html
>
> Best wishes,
>
> Paul H.
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Received on Wed 13 Jun 2012 02:47:25 AM PDT