As with other evolved creatures, our sight and hearing are sensitive only to the parts
of light and sound vital to our survival. We can't see infrared radiation, though
we can feel part of it as heat, and ultraviolet radiation is invisible to us, though
not to some other animals. Elephants use sound at frequencies so low that we've
realized only recently that they communicate in this manner. On the other hand,
we've known for decades that the life of bats is built around sounds pitched far
higher than we can hear.
But as in many areas of human existence, ignorance can kill. Among the
"invisible" frequencies of the sun's rays are those that set the stage
for skin cancers. This is especially a problem in our desert, where there are few
clouds and little water vapor to blunt the solar radiation. The darker skin of Native
Americans gives some advantage over the lighter skin of European descent, but the sun
ultimately plays no favorites. Remember, we all can fall prey to the deadly rays of the
sun.
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.
Skincheck: Melanoma Education Foundation.