No. 11: Summer 1980
A flurry of papers and at least one TV documentary have widely promulgated the news that many life forms thrive near the thermal vents 2,550 meters under the sea along the Galapagos Rift. Mollusks, worms, crabs, and other forms of life make up a successful biological community where light never penetrates. Terrestrial heat rather than the sun keeps this life going. The geothermal heat reduces sulfur compounds emitted from the vents and chemosynthesis proceeds up the biological ladder without need for sunlight.
(Karl, D.M., et al; "Deep-Sea Primary Production at the Galapagos Hydrothermal Vents," Science, 207:1345, 1980.)
Comment. The implications are far-reaching. Does life exist at great depths in the earth and beneath the apparently lifeless surfaces of the other planets? Photosynthetically sustained life may represent only a small slice of the biological pie. Was sunlight necessary for life to originate and evolve -- assuming it did each?