January 27, 2010

Aliens Could Be Right Under Our Noses

The question of whether there is life on other planets has kept scientists searching for years, but it now appears that the answer has come in variant life forms, likely miniscule microbes, found right here on Earth, according to award-winning Arizona State University physicist Paul Davies.

Variant life forms could be hanging around "right under our noses "” or even in our noses," Davies told the Associated Press.

"How do we know all life on earth descended from a single origin?" he told a group of scientists Tuesday at London's Royal Society, which serves as Britain's academy of sciences.

"We've just scratched the surface of the microbial world."

The possibility of alien micro-organisms existing on Earth is not a new concept, Jill Tarter told the Associated Press. Tarter is director of Search for Extraterrestrial Intelligence (SETI), a U.S.-based project that listens for signals from civilizations around distant stars.

Many scientists involved in the project wanted to take a deeper look into the subject, which was written about in a 2007 Scientific American article by Davies, titled "Are Aliens Among Us?"

Scientists have yet to find the answer to that question, and Davies himself admitted that finding one would be incredibly hard.

There is an abundance of unusual organisms, such as chemical-eating bacteria that abide deep in the ocean and organisms that thrive in boiling-hot springs. However, this is not enough to prove that they are completely different life forms.

"How weird do they have to be to suggest a second genesis as opposed to just an obscure branch of the family tree?" he asked. He went on to even suggest that the only way to prove that an organism was alien would be if it were built using exotic elements possessed by no other life form.

Bruce Jakosky, an astrobiologist at the University of Colorado at Boulder, said the idea of alien life on Earth was "an interesting theoretical idea," but one that would be impossible to put odds on since "we have no idea what we're looking for."

If such life forms exist, they would not likely pose a threat to humans, as their different biochemistry would tend to decrease the likelihood of infection or disease, he added.

Davies also cautioned against anyone getting carried away, because the idea needs definite verification. Yet he still noted that the vast majority, less than one-percent, of the bacteria in the world has been studied comprehensively, meaning there is much left to discover.


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