Domino theory has long been a part of the political world. The name comes from a pastime of children who set the rectangular dominos on end in a file or gentle curve. Knock one over and a wave of falling dominos, each striking the next one in line, mows them all down. In politics, governments feared that if a key nation fell to the enemy, others would swiftly follow.
Ecologists have similar fears—that the extinction of a key
species will send a cascade of losses throughout the plants and animals of the land. A
problem is that we know too little about ecological interrelationships—but we do
know that there are interdependencies in every biological community. What's worse,
we have the recent fossil record that may show just such a collapse. Our northern
desert area in the last ice age supported a diverse fauna of herbivores: mammoth,
bison, brush ox, three or four species of horses, two camels, two or three deer,
bighorn sheep, and at least three of the antelope-like pronghorns—two-thirds
quickly extinct. Dominos anyone?
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.