At io9, Annalee Newitz argues that five earth-bound creatures that live under extreme conditions make the idea of life existing on other planets realistic. One of them, pictured above, is a tube worm that lives in the extreme heat of the ocean floor near volcanic vents:
They live at the edges of molten-hot volcanic vents deep beneath the ocean, and they feed on sulfides delivered to them by local bacteria. These giant tube worms, which can reach 7 feet in length, live a mile below the ocean surface under extreme pressure. Their tips are bright red because they're filled with blood - these worms are seriously packed with blood vessels. And they prefer live at the edge of "black smokers," volcanic vents where temperatures can be extremely hot.
What does this tell us about life on other planets?
The interesting thing about giant tube worms isn't that they can withstand extreme heat, but that they can gain nourishment in an environment with chemistry radically different from our atmosphere. They're basically eating sulfides, which are abundant on planets like Venus, where it occasionally snows iron sulfide. Could tube worms thrive on Venus, with its heat and high pressures and sulfide weather?
Link | Photo: NASA