Some of the species are just plain odd, and others demonstrate how little we still know about this planet. Take the new nematode species Halicephalobus mephisto. It's named for Faust's demon Mephistopheles, because it lives in hellish, hot conditions in the bowels of the Earth. It was discovered in a mine in South Africa, and carbon dating suggests the worms have been living there between 3,000 and 12,000 years. The worm was a brilliant find for exobiology, because it proved that multi-celled organisms can subsist completely isolated from other complex ecosystems.