Killer Antibiotics

A recent editorial in the L.A Times, "Resisting Antibiotics," stated that "The rise of bacteria such as methicillin-resistant Staphylococcus aureus, or MRSA, which kills more people in this country each year than AIDS, is believed to be a consequence of the overuse of antibiotics in humans and animals."

The editors argued that stricter guidelines for antibiotic use in farm animals and livestock be imposed to prevent the situation from becoming even more dire.

Frequently omitted from stories about killer antibiotic-resistant bacteria, however, is how they came to be. Simply saying that antibiotics are overused doesn't explain how antibiotic-resistant strains develop; and it isn't by divine intervention.

Such bacteria do not just happen by accident, but by a process that approximately 50% of the American population still don't accept -- evolution by natural selection. Only this time, we humans are the agents selecting the killer bacteria by overusing antibiotics.

The process is elegantly simple. Antibiotics kill most of the bacteria they are meant to, but not all. Those that are not killed are naturally resistant, which means that we must develop new antibiotics to kill them. We end up in what evolutionary biologists call an "arms race," with the bacteria currently winning. So, for all the evolution naysayers and intelligent designers out there, here is direct and immediate evidence of evolution by natural selection.

For everyone else, this story shows how an understanding of how the world really works, in this case, evolution by natural selection, may actually save us from ourselves.