Science has long known that some microorganisms flourished at high temperatures. As early as 1924, a researcher suggested that the first forms of life were thermophiles that had originated in hot springs. But scientists did not speculate on the existence of hyperthermophiles until less than two decades ago. These organisms prosper at temperatures near and even at 100-degrees C, the boiling point of water. Even more important, perhaps, scientists led by Dr. Carl Woese of the University of Illinois, used a cutting-edge technique to discover that hyperthermophiles are the most slowly evolving of all extant life forms. These facts together led many scientists to conclude that life may first have evolved on Earth under hyperthermophilic conditions.
In a sense, it's not surprising that important discoveries about the origins of life are coming from microorganisms, since they are so varied.
"Some bacteria are much farther apart on the phylogenetic scale from other bacteria and archaea than humans are from plants," said Wiegel. "Man is much, much more closely related to the cockroach than most bacteria are to other bacteria."
Indeed, science may know less than one percent of the existing species of microbes on Earth while knowing probably 99 percent of all animals and more than 95 percent of all plants. Bacteria that flourish in hot conditions, in fact, can be found nearly everywhere, from the soil to compost heaps. But the ones that live under the most extreme conditions of heat may reveal more to science about the origins of life.
While a number of the chapters argue that life might have begun in
conditions such as
those now found in hot springs or in undersea thermal vents, the book is not
unanimous on this point. In fact, a chapter written by Stanley Miller of UC-La
Jolla and Antonio Lazcano of the University of Mexico argues that life did not
and could not have begun at the grow
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Contact: Phil Williams
philwpio@arches.uga.edu
706-542-8501
University of Georgia
10-Nov-1998