Life Didn’t Start on Hot Clay 02/13/2006
Strike off one more proposal for the origin of life. “Darwin’s warm pond theory tested,” announced the BBC News, but it was found wanting.
Origin of life researchers have long recognized the serious problem of concentrating organic molecules in a primordial soup such that they could interact and grow. A popular ingredient in the mix in recent years has been clay. Some suggested that organic molecules could adhere to the surfaces of clay minerals and thereby get close enough to join hands. Rather than occurring in the open ocean, they suggested this process might occur in hot springs or at deep sea vents.
David Deamer (UC Santa Cruz) has revealed a difficulty with this proposal; “in our experiments,” he said, “the organic compounds became so strongly held to the clay particles that they could not undergo any further chemical reactions.” That appears to bring the clay scenario to a dead end. “The results are surprising and in some ways disappointing. It seems that hot acidic waters containing clay do not provide the right conditions for chemicals to assemble themselves into ‘pioneer organisms.’” Deamer is not ruling out the “warm little pond” scenario completely, but his findings dash cold water on hot springs or hydrothermal vents.
The results, not yet published, were presented at an international meeting at the Royal Society to discuss the latest ideas on the origin of life. About 200 were in attendance. Organizer Ian Smith (U of Cambridge) explained the reason for the conference: “Understanding how life emerged on Earth within 1,000 million years of its formation is both a fascinating scientific problem and an essential step in predicting the presence of life elsewhere in the Universe.” Nevertheless, the BBC stated, “While our understanding of the world is rapidly increasing, the answer to how life began on Earth remains elusive.”
