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Desert Diary
Plants/Floral Change


We hear a lot about the effects of mankind on the flora of the natural world--and rightly so. But this emphasis tends to make us forget that animals always have played a part in shaping the natural landscape. Consider the spectacle of an estimated 60 million bison not only feeding on, but also trampling, the grasslands of North America. Who could deny that the effect on the prairie must have been stupendous? And buffalo wallows are still visible in places serving to collect a little bit of extra moisture for a pocket of different vegetation. The grasslands are open in part due to periodic fires, but think of the fate of any tree grown large enough to act as a scratching post for itching bison as they shed their shaggy winter coats.

The vast numbers of bison encountered by the early European explorers likely were a consequence of earlier events. Bison seemingly gained ascendancy only with the extinction of North American horses, camels, and most species of pronghorns. Change happens—sometimes for better, sometimes for worse.
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Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.

Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.


Bull bison wallowing. Photo by Gerald and Buff Corsi, California Academy of Sciences. © 2000 California Academy of Sciences.