Pleistocene Megafauna

Pleistocene megafauna.  Until just yesterday . . . 10-11,000 years ago . . . Disappeared for mysterious reasons on the heels of the human invasion.  All invaders plunder.  Waste.  Undergo a population explosion at the expense of everything else.

And it is always the big animals (and the big trees too, for that matter) that are easiest—and first—for people to wipe out.  Because they are fewer, slower to reproduce and grow, less fecund, and of course more attractive (you can get a lot more meat, or a lot more lumber—by killing one giant than a hundred dwarfs).  And when the giants are all used up, they are not quick to return.  Ask yourself:  is it easier to wipe out elephants, or gophers, or mosquitoes?

On the other hand, an episode of very intense cold and dry conditions at the end of the last glaciation, a sudden reversal just as all was warming up, marked the end of the megafauna.  It may be that this did indeed wipe out the northern populations that were the survivors of the hunters, while humans wiped out the more southern populations.

In any case, the northern, rich, diverse “prairies” soon turned into boring reproductive monotonous taiga  when the mammalian lawnmowers (especially the mammoth) disappeared.  Just the cows today!  I wouldn’t doubt if this was the genesis of the vast Asian taiga even.

Gone were thirty genera of large mammals (and birds?) (in North America only?) and fifty-two? species.  Whereas the little animals are still with us today.

Cf Yosemite Valley:  Remove Indians and their fires, get solid Ponderosa Pine instead of productive Black Oak “orchards” and rich meadows.  Cf Tuolumne Meadow:  Remove Indians and their fires, get solid Lodgepole Pine instead of productive prairie.  Diversity becomes monotony.  This example is directly applicable to subarctic scenario.  (Or should this be referred to the “lake becomes meadow becomes forest” scenario?)

Computer models show that even light hunting can have devastating consequences on elephants.  People are scattered over the whole continent, like their prey.  The behavior of the elephant is against them—they live in extended-family groups, and are psychologically easily stressed.

This accounts for why bison alone of the big mammals (except moose, elks, and grizzly bears) survived.  They live in huge, migratory herds and reproduce fast.  Feast or famine for their predators.