Feral dogs, feral cats, feral horses—what's with this word "feral"? Although often used merely to mean savage, naturalists use it to refer to domesticated animals that have gone wild. Thus the wild horses and burros of our continent can be considered feral, because they all are descended from domesticated animals introduced from the Old World. The various kinds of New World native horses had died out thousands of years earlier.
It's not always apparent even to the biologist whether we are dealing with natural occurrences or cases of human intervention. Take the Wild Turkey. This bird occurs adjacent to the Chihuahuan Desert in mountains that support good woodland or forest. They also occur in much of New Mexico to the north. Long considered native there, it only has been in recent years that we've realized that most New Mexican turkeys are descendents of escapees from Pueblo domesticated flocks. Fossil turkeys from that region were a different, now extinct, species (the Big-footed Turkey).
Thus biological communities evolve—sometimes naturally, sometimes
under the hand of man.
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.
Addendum, 30 March 2012: Since this Desert Diary episode was presented, Wild Turkey fossils have been recovered from two caves in the Sandia Mountains, east of Albuquerque, sowing uncertainty about the origin of modern forms.
Rea, A. M. 1980. Late Pleistocene and Holocene turkeys in the Southwest. Contributions in Science, Natural History Museum of Los Angeles County, 330:209-224.
Feral Horse. Focused on California, but much information on their biology.
Feral Pig, Mammals of Texas
- Online Edition.