Life may have begun in clay
LIFE MAY HAVE BEGUN IN CLAY
Mountain View, California:
The theory that life arose from a chemical “soup” in the oceans is being challenged by scientists who have found evidence that a common clay possesses basic properties essential to the generation of life.
“The functional attributes that we associate with life are not necessarily confined to organic systems,” said Lelia Coyne, a San Jose State University chemist who led the research team.
The researchers have verified that clay can store and transfer energy, which would allow it to act as a chemical factory for the generation of life, they told a symposium last week at the National Aeronautics and Space Administration’s Ames Research Center.
The “clay-life theory,” first proposed in the 1960’s by chemist Graham Cairns-Smith of the University of Glasgow, challenges the long-favored notion that life emerged from the primordial oceans after millions of years of chemical reactions between simple organic molecules.
It also is reminiscent of the Bible’s account in Genesis of the Creation, which says, “And the Lord God formed man of dust of the ground,” and refers to it commonly as clay.
Cairns-Smith said he believes that clay was not just a catalyst for life but the actual “low-tech” material that gave rise to progressively more sophisticated or “high-tech” life forms.
“The recognition that many of the specific functions of living systems can be performed by inorganic molecular systems is forcing us to re-examine, at a real, fundamental level, the definition of life,” Coyne said.
The “primordial soup” theory, set forth in the 1930’s by the Soviet scientist A.I. Oparin, suggests that the chemical evolution of life was random, while the clay-life theory proposes a patterned development.
“Most of the chain-lengthening organic reactions that have to occur [to create life] … occur through the elimination of water. It’s hard to eliminate water in an aqueous environment,” Coyne said. “You can have an awful lot of organic matter, but if you dump it in the water, it may not look like much. If you want to lengthen chains, you have to have a lot of these molecules close together. It’s easier to grow things on surfaces.”
Research by Armin Weiss of the University of Munich suggests that clay, which has a mineral structure almost as intricate as a DNA molecule, could be capable of such lifelike attributes as reproducing crystal structures from a “parent” clay to several generations of “daughter” clay.
Cairns-Smith suggests that the creation of life could have been directed by an inorganic pattern developed in clay.
Other theories, such as that life reached Earth from outer space in the form of spores, do not answer the fundamental question of creation – for instance, what created the spores?
The finding that a common ceramic clay can store and transfer energy – sometimes in the form of radioactivity – has been confirmed through experiments showing that clays release soft ultraviolet light when they are wetted with organic liquids or water, irradiated, dried, crushed or ground up.
Despite the new evidence, “the majority of people who work on the origin of life would probably still vote for the old- fashioned soup,” said Leslie Orgel, a biochemist at the Salk Institute in La Jolla.
Lisa Levitt Ryckman … On Associated Press, April 7, 1985