Monday, July 20, 2009

~ the shadow biosphere

What if current conditions on Earth were perfect for the genesis of life? Not life as we know it, but another kind, a different kind starting anew from the inanimate organic soup - while we happily continue on our way, ignorant of a new challenger rising from beneath. Something based on a triple or quadruple helix perhaps, or on plastic, neon and carbon monoxide. Perhaps something congealing in the anoxic depth of the Gulf of Mexico ...

Perhaps the havoc we are wreaking on the planet is making conditions perfect for this new genesis, perhaps our toxic effluents are providing the perfect nutrient mix.

I was going to write a story about this. I have a few scribbled pages in a notebook. But after hearing Paul Davies speak on the Science Show the other week [4 July], I don’t think I’ll bother.

In an absolutely fascinating address, he discusses something he calls the ‘shadow biosphere’. He posits the notion that life may have originated more than once on the Earth, and, asks, if this were the case, how we would go about finding it.

If it was something that has faded away, then we would have to look for ‘ancient biomarkers in the fossil record’ but, if not, if there is indeed a shadow biosphere currently intermingled with our own, he suggests a number of methods by which we could identify it.

Firstly, it would have to be small. If were anything more than microscopic we would have noticed it already. But the vast majority of life on Earth is microscopic and the vast majority is unresearched and unsequenced. If this shadow or ‘weird’ life was ecologically separate, we might find it by subjecting samples to extremes of radiation, acidity, or general contamination, or by looking into extreme environments like the upper atmosphere or around super-hot hydrothermal vents. If it was ‘integrated into our ecology’ we could examine how it cycles carbon [if it is carbon-based], or the chirality [handedness] of the compounds from which it is formed. Davies also suggests that weird life may process arsenic instead of phosphorus.

He presents the enthralling possibility that there may conceivably be, rather than a tree, a forest of life on Earth.

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Marshall-Stacks said...

usual imaginations of
'other life' forms, have a
negative and/or threatening image; but I like to think that if they have a Cerebral cortex, that any New Others will be
Positive and Helpful, Enlightening and Instructive.
That 'They' will know how to eradicate bogans and rednecks, fundies and farkwits, with the result that Policing will become redundant, and the rest of us can relax and enjoy the good stuff on this planet.

Sam Sejavka said...

hear! hear!