Ever see a cat get watered—not a happy sight! Yet, if you're spraying water around a somewhat overgrown yard, it's amazing how easy it is to inadvertently hose down a feline happily snoozing away in the grass. Camouflage really works, even when as imperfect as that of most domestic cats.
The ability to blend in is one of the most widespread phenomena in the animal world—and apparently one of the easiest for natural selection to shape. Animals have a range of genetic variation in virtually all characteristics. When a variation in coat color or pattern helps an animal to escape notice just a little bit better than others in the population, the bearer is more apt to survive and pass on its genes than is a more conspicuous relative.
The Chihuahuan Desert abounds with examples, with such animals as the walking stick, looking like a twig, or the Spotted Ground Squirrel, blending in with its sandy background.
Jealous? Remember your school days, when you would have given anything
to have been invisible at question time!
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.