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Monday, November 23, 2009

Photo: Earliest Animals Were Sea Sponges, Fossils Hint


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Fish glide past barrel sponges on a coral reef in an undated photo.

Sea sponges were thriving about a hundred million years before the evolutionary growth spurt that gave rise to modern animals, according to a February 2009 study. Fossil steroids produced by the sponges are now the oldest known fossil evidence of animal life, the study says.

Photograph by Commander William Harrigan/Florida Keys National Marine Sanctuary/NOAA