Life on Earth exists literally everywhere, in wildly varied forms and in
every conceivable environment, so why not in other environments
elsewhere? Microbes, after all, are even now chewing on hydrocarbons
from the disastrous BP oil spill that persists at the bottom of the Gulf
of Mexico 2 miles down, where it's perpetually dark and airless.
Even more advanced forms of life, like giant clams, crabs, shrimp and
strange tube worms, are now thriving in near-boiling water at the mouths
of
volcanoes deep undersea. Such life was discovered more than 20 years ago
8,000
feet down in the Galapagos Rift Zone, where giant plates of the Earth's
crust are slowly splitting apart and sulfur-eating bacteria have evolved
in
the airless total darkness to provide nourishing energy for the higher
life-forms around them.
The highly radioactive wastewater and toxic sludge left over from the
Hanford plutonium reactors in the state of Washington would kill any
animal or
human instantly. But bacteria called Deinococcus radiodurans have been
discovered multiplying there and withstanding radiation a thousand times
the levels deadly to humans.
In the sulfurous gases of a deep, dark South African gold mine, where
oxygen is nonexistent and temperatures run higher than 140 degrees,
there's a
thriving bacterium with a whip-like tail called Desulforudis
audaxviator. That creature gets its energy from the decay products of
uranium, creates its oxygen from saltwater circulating in the rocks
around it, and nourishes itself with organic molecules from water,
carbon and the ammonia in the rocks of its happy habitat.
Hardy microbes thrive in the boiling fumaroles and geysers of Mount
Lassen
and Yellowstone, while others have evolved to colonize the polar ice
caps
of the Arctic and the frigid glaciers of Antarctica.
All these organisms are known as "extremophiles," and there's no extreme
environment on Earth today that isn't home to one or more of them - some
with genetic lineages millions of years old.
In fact, every ecological niche on Earth is occupied today by the living
creatures that have evolved to fit in there.
Read more:
http://ow.ly/2V9zl
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