>However, Paul S. Martin's "Pleistocene Overkill" theory is considered
>entirely without merit by myself and my archaeological colleagues. His
>claim that the loss of 31 genera of mammalian megafauna at the end of the
>Pleistocene in North & South America was due primarily if not entirely to
>predation by "big game hunting" Paleoindians using spears tipped with
>Clovis points requires us to believe that these people were somehow
>motivated to massacre 5x to 50x the animal biomass they would have
>required to meet their per capita food energy requirements. It takes
>effort to dispatch a mammoth or a mastodon. It is totally absurd to
>assume people would so waste their finite energies for the sheer blood
>lust of it.

Whether or not the overkill theory can be defended in North America (but see
below), I submit that there is ample evidence from other parts of the world
to show that the arrival of aboriginal peoples in uninhabited areas was
followed, often in short order, by some faunal collapse. I believe it is
pretty much universally accepted that the moas of New Zealand were
exterminated by humans. Work by Storrs Olson and others on oceanic islands
has shown that a large number of bird extinctions followed human settlement;
this is particularly marked in Hawaii, where some forty species disappeared
including flightless geese and ibises. As these areas were settled
relatively recently it is easier to establish timelines than for continental
areas, and I admit that continental faunas may have been more resilient to
invaders, but I believe this data is at least suggestive.

Furthermore, studies of faunal changes in areas of Africa after the removal
of megafaunal populations has shown that extinctions can occur by a sort of
ripple effect. Megafauna can alter habitat in a way thatcreates niches for
other species that may disappear if the megafauna are removed - so one
extinction can lead to others. Therefore if a connection can be drawn
between human activity and the extinction of even a few of these species it
may be possible that our actions led, at one or more removes, to some of the
others.

On the specific issue of human-mammoth interactions see G. Haynes 1991,
"Mammoths, mastodons and elephants" (Cambridge U. Press). Chapter 7 (pp.
264-317) deals with the extinction of mammoths in North America in great
detail. While Haynes does not accept the overkill theory holus bolus, he is
open to the idea that Clovis hunters may have, by adding to the stresses on
an already stressed population, made it impossible for these animals to
recover (p. 317):

"But Clovis hunters perhaps made an already bad situation worse for
megamammals: While climatic changes were driving proboscideans to die off
[that is, suffer a serious but not terminal population crash], the added
stress of Clovis hunting drove them to die out. In the absence of Clovis
hunters, mammoths and mastodonts (and other megafauna) should have been able
to survive the changing conditions of terminal Pleistocene environments.
What I am leading up to is my inability to reject the prospect that
Pleistocene proboscideans were in fact killed off. I cannot discard this
possibility in spite of the fact that the best evidence I can find does not
contradict the thesis that drought or some other serious environmental
stress accounted for the terminal Pleistocene accumulations of mammoth and
mastodont bones."

Haynes notes that modern elephants have a remarkable ability to recover from
severe environmental stress, with human hunting the obvious exception. His
scenario may or may not be correct, but it involves far less actual
slaughter than is supposed above and seems to me at least to be more plausible.
--
Ronald I. Orenstein Phone: (905) 820-7886 (home)
International Wildlife Coalition Fax/Modem: (905) 569-0116 (home)
Home: 1825 Shady Creek Court Messages: (416) 368-4661
Mississauga, Ontario, Canada L5L 3W2 Internet: ornstn at inforamp.net
Office: 130 Adelaide Street W., Suite 1940
Toronto, Ontario Canada M5H 3P5