Hiding in Plain Sight: The Domain of Life We Missed Until the 1970s
The domain of life constituting 20% of Earth’s biomass has proven important to practically every field of science
Yellowstone Park, USA is home to a colourful and diverse range of life. Every year, millions of tourists crowd around hot geysers and thermal pools, their floors covered in brilliant blue and emerald-green mats. The strangest, most fascinating form of life was teeming under the steaming surface waiting to be found. Professor Thomas Brock was vacationing in 1964 when he first saw these mats.
I got out of the car and, by chance, a ranger was giving a talk near a thermal pool. I saw all this color, and he said it was blue-green algae. I got interested right away.
Curious, he yearned to uncover the organism thriving in such an extreme environment. There he discovered an unknown microbe that he named Thermus aquaticus. He called this oddity an extremophile because it thrived in unforgiving environments [1]. In his landmark 1967 paper, Brock concluded there is no upper-temperature limit for life [1]. He could never have guessed that the other species lurking in the geyser were like nothing we’d characterized before.
