Lake Vostok Found Teeming With Life

jpyeck writes "Lake Vostok, Antarctica's biggest and deepest subsurface lake, might contain thousands of different kinds of tiny organisms — and perhaps bigger fish as well, researchers report. The lake, buried under more than 2 miles (3.7 kilometers) of Antarctic ice, has been seen as an earthly analog for ice-covered seas on such worlds as Europa and Enceladus. It's thought to have been cut off from the outside world for as long as 15 million years. But the latest results, reported in the open-access journal PLOS ONE, suggest that the lake isn't as sterile or otherworldly as some scientists might have thought. More than 3,500 different DNA sequences were identified in samples extracted from layers of ice that have built up just above the surface of the lake."

It's not contamination

[dfm3]

If you read TFA, you'll see that 1) they did sequence DNA, 2) they found many, many species which are not the usual ones associated with contamination due to methodology, and 3) they found organisms that can theoretically survive in the extreme and varied environments believed to be present in the lake (thermophiles near suspected geothermal areas, halophiles in brackish/salty water, etc). As a microbiologist, I find it fascinating that the authors not only provide a list of species, but go so far as to paint a complete picture of how each could possibly exist in a completely functioning ecosystem. For example, they found organisms responsible for carbon and nitrogen fixation, and hypothesize that these same species will also be found throughout the lake water in their various niches.

Re:"More than"

[Samantha Wright]

The exact number is 3,507. I hope you're now able to sleep well at night.

...and if you're curious, that number is actually extremely low by the standards for this type of experiment; they didn't analyse anywhere near enough data. Metagenomics is supposed to take up gigabytes of disk space; the amount of usable data they got was around 37 MB.