Microbiologist Thomas Brock was tramping through Yellowstone in the 1960s when he stumbled upon a species of bacteria that would transform medical science.
Brock was investigating the tiny life-forms that manage to eke out a living in the superheated waters of the park’s thermal pools. There, he and a student found golden mats of stringy growth in Yellowstone’s Mushroom Spring containing a microbe that produces unusual heat-resistant enzymes.
Today, those enzymes are a key component in polymerase chain reaction, or PCR, a method used widely in labs around the world to study small samples of genetic material by making millions of copies. This technique, which would have been impossible without the discovery of heat-resistant bacteria more than half a century ago,