Buried alive: Half of Earth's life may lie below land

Scientists estimate that about half of living creatures live on the planet hidden in or beneath the ocean or in rocks, soil, tree roots, mines, oil wells, lakes and aquifers. They call it the "sunsurface biosphere," a dark world where sun and stars don't shine.  "Earth's habitable zone extends to depths of hundreds or thousands of meters," says Katrina Edwards, a microbiologist at the University of Southern California, Los Angeles. "The organisms that live in this envirnment may collectively have a mass equivalent to that of all surface dewellers and may provide keys to solving major environmental, agricultural and industrial problems".  Scientists say research on "intraterrestrial life" complements astromers' hunt for "extraterrestrial life" around other stars and planets. The search for E.T. starts at home.  To advance their understanding of subsurface life, marine geogogists are about to launch three drill ship expeditions to explore the seafloor and implant long-term scientific "observations" intsruments.

source:  Robert S Boyd,  McClatchy Newspapers.