Many people misjudge the number of kinds of mammals in an area because most mammals tend to be nocturnal, wandering about out in the open only at night. On the other hand, people are—mostly—diurnal, active during the daylight hours. Or at least we were until artificial illumination became possible. We share the diurnal nature with our close relatives and with a few other mammalian groups.
If, in wandering through our desert, you happen to see a small mammal
scampering about during full daylight, guessing that it's a member of the squirrel
family is a pretty good bet. Almost all of the squirrels other than the flying
squirrels snooze the nights away and go off to work after sunrise. Lacking the lowland
forests common in the better watered parts of the world, the hot Chihuahuan Desert
boasts mostly of ground squirrels and prairie dogs. Rock Squirrels, Texas Antelope
Squirrels, Spotted Ground Squirrels, or Mexican Ground Squirrels inhabit almost every
acre of our desert, and in the higher grasslands, a few Black-tailed Prairie Dogs
manage to hang on.
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.