A popular group of religious publications, the "Left Behind" series, warns of the fate of sinners left behind to meet their fate. But for some critters, it's not always such a bad thing—at least, when you consider the alternative. And for many plants and animals, the alternative is death.
The Eastern Mole is a good example of this. Requiring moist loamy or
sandy soils and a rich, underground food source of insects and other invertebrates, it
soon disappears when its needs aren't met. Back in moister times, these fossorial
animals that spend their entire lives underground extended far west of their
present-day, main geographic range. Increasing aridity on the western margin slowly
drove local populations into extinction. There were, however, a couple of favored
patches forming islands of suitable conditions in the sea of developing dryness—patches
where moles continued to eke out a living, unaware even that they'd been left
behind. Thus, marooned in the eastern parts of the Chihuahuan Desert, in Presidio
County, Texas, and in Coahuila, Mexico, two populations have survived for
millennia.
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.
Painting by Louis Agassiz Fuertes of an Oregon Mole (a good image of our species being not available) with its prey. After Nelson, 1918.
A mole has been obtained recently (2003) in Coahuila—apparently the first one taken in over 50 years. So, the population still hangs on.
Nelson, E. W. 1918. Wild animals of North America. National Geographic Society, Washington, D.C. 612 pp.
Schmidly, D. J. 1977. The Mammals of Trans-Pecos Texas. Texas A&M University Press, College Station. 225.