These hardy bacteria subsist on minimal water and only the nutrients they can extract from the subterranean rock. And they do it in total darkness. The microbiologists tested the bacteria against more than 25 different antibiotics, expecting these bacteria to succumb to these modern drugs. Instead, they found that all the microbes were resistant to at least one of the antibiotics. This surprising discovery suggests that bacteria have an ancient mechanism for evading toxic chemicals. Microbiologists have assumed that today’s antibiotic-resistance crisis was caused by increasing exposure of germs to antibiotics in the past 50 years. That is undoubtedly still true, but the newly discovered cave bacteria might give clues as to how germs evade drugs that they have never before confronted.

Rich mixtures of bacteria live in Lechuguilla Cave, Carlsbad Caverns National Park, 1,600 feet below the Earth’s surface. [Dave Bunnell, 2007]