extremophile

No, an extremophile is not an enthusiast of extreme sports (though -phile does mean "one who loves or has an affinity for"). Rather, extremophiles are microbes that thrive in environments once considered uninhabitable, from places with high levels of toxicity and radiation to boiling-hot deep-sea volcanoes to Antarctic ice sheets. Scientists have even created a new biological domain to classify some of these microbes: Archaea (from Greek archaios, meaning "ancient"). These extremophiles may have a lot in common with the first organisms to appear on earth billions of years ago. If so, they can give us insight into how life on our planet may have arisen. They are also being studied to learn about possible life forms on other planets, where conditions are extreme compared to conditions on Earth.