We think of evolution as something that happens over millions of
years—and so it does. But it also happens in the here and now. A major problem caused
by current evolution is the spread of bacteria immune to antibiotics. What's
particularly disheartening is that part of this problem is our own fault. Organisms
adapt by natural selection, which is short-hand for any number of things that allow
critters with one genetic makeup to out-reproduce those with a different inheritance.
If we'd use antibiotics the way they were meant to be used, there would be little
problem. But how often do people stop taking antibiotics before the prescribed supply
is used up—because, after all, they're feeling better? But this allows less
susceptible bacteria to survive and reproduce, and now there's a population of more
resistant bacteria at large. Do this again and again, and eventually you have bacteria
that the antibiotic can't begin to faze. And we along the border, especially with
cheap medicines often available without bona fides prescriptions across the line, are
part of the problem.
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.