Some like it very hot

By Bryan Appleyard

Russian scientists have now poured 60 tonnes of freon and kerosene down the four-kilometre bore hole that plunges through the ice above Lake Vostok in Antarctica. This will stop the hole freezing up during the long Antarctic winter. When summer comes, the Russian team will return to drill the last 100 metres and expose the surface of a lake that has been buried beneath the ice for at least 15m years. Eventually they intend to explore this lost world, a place unseen by human eyes, with a robot submarine.

The temperature of the lake is about -3°C, but the water remains liquid because of the pressure exerted by the ice sheet. The pressure should also have kept the water super-saturated with oxygen and nitrogen. Once we would have assumed that this cold, lost lake would be no more than a geological curiosity, a dead relic of the time when Antarctica separated from Africa and drifted south. Now we can be almost certain that it is full of life. Most of these creatures will be tiny single-celled organisms, microbes, visible only under a microscope. But they will have novel genetic structures, they will use previously undiscovered enzymes and they will have evolved unique survival strategies. They will be a class of creature now known as extremophiles, lovers of extreme conditions.