It's a kind of genetic photocopying, and it became the basis for all subsequent genetic science, from academic studies to police forensic work. It won Mullis the Nobel Prize in chemistry in 1993.

Meanwhile, scientists were finding even hardier microbes, now known as hyperthermophiles, which demand temperatures of 80 degrees centigrade (176 degrees Fahrenheit) or more. The warmest organism found so far, according to Frances Ashcroft in Life at the Extremes, is Pyrolobus fumarii, which dwells in the walls of ocean vents where the temperature can reach 113 degrees centigrade (235.4 degrees Fahrenheit). The upper limit for life is thought to be about 120 degrees centigrade (248 degrees Fahrenheit), though no one actually knows. At all events, the Brocks' findings completely changed our perception of the living world. As NASA scientist Jay Bergstralh has put it: "Wherever we go on Earth——even into what's seemed like the most hostile possible environments for life—as long as there is liquid water and some source of chemical energy we find life."