Dry valleys McMurdo, Antarctica may seem one of the least hospitable places on Earth. It is a cold desert where only the wind searches rocky land and water exists only in the form of ice, the remaining including those times when the valley was covered by the ocean. In short, it's so sad area of the planet that NASA decided to simulate Martian conditions.

Now imagine the surprise of biologists found in this place many different ecosystems. Not on the surface, of course, and under the ice in the salt lakes, which for thousands and millions of years isolated from any external sources of energy and nutrients. In the new study experts have described one of the youngest subglacial lakes, which remained isolated only a few thousand years. Although theoretical estimation talked about the fact that local bacterial community must starve, analysis of water samples have shown that organisms feel fine, eating products of chemical reactions between water and bottom.

Perhaps the most famous sight of the Dry valleys McMurdo - Bloody waterfall, where iron stain the ice in red color and at the same time fuels bacterial community, got there about 1.8 million years ago, when sea Bay were cut off from the ocean and froze under the glacier. Described here is the lake View is located in another valley and, apparently, was in isolation is not so long. It is very salty and does not freeze at a temperature of -12 C. ice Thickness over the water is 16 meters Radiocarbon Dating has shown that the lake exchanged carbon with the atmosphere for at least several thousand years ago.

The scientists believed that organisms if they are still there, are in the final stages of decomposition, that is, some microbes are still supplying the latest organic compounds, releasing methane.

It turned out, however, that anoxic lake is rich in organic compounds, including carbohydrates, and methane there a little. Also found in the water a significant amount of hydrogen. Nitrogen compounds are too frequent, especially nitrous oxide and ammonia. This mixture of reduced and oxidized compounds says that before the final decay is still very far.

Who lives there? Judging by the DNA sequences, 32 species representing eight types of bacteria. What moves them metabolism exactly is unclear. It is only obvious that methanogens in the lake do not dominate. By the way, it should be noted that the samples are completely absent archaea, often in extreme conditions.

The chemical composition of water suggests that bacterial community feed molecular hydrogen vacated as a result of reactions between water and iron silicate bedrock. Then hydrogen could be included in the composition of complex organic compounds. If this is true, lake View has a completely different source of energy than Bloody waterfall.

This is a rather important conclusion, because it assumes that a variety of simple, natural chemical reactions able to provide the energy necessary to sustain life, even in the absence of such things as sunlight or plate tectonics. This, in turn, should affect our view of the prospects of finding life in ice oceans Europe or possible subsurface salty lakes of Mars.

Another intriguing perspective is that almost all dry valleys may be the house of ecosystems with different degree of isolation, as well as with different sources of chemical energy that can withstand any cataclysms up to the global glaciation.

The study is published in the journal PNAS.

Prepared according to Ars Technica.