Scientists have discovered an Antarctic ecosystem of microorganisms cut off from light and oxygen for as many as 2 million years, the Guardian reports. The microbes, living under one-third of a mile of ice, in a 14-degree lake four times as salty as seawater, give researchers clues to how life could exist on other planets, and how it survived on Earth during extreme conditions in the past.
The researchers believe the organisms, lacking oxygen, “breathe” iron. Without sunlight for photosynthesis, they may subsist on organic matter locked in the lake with them. DNA analysis shows “species living there are similar to contemporary organisms, and yet quite different,” said a scientist. “A result, no doubt, of having lived in such an inhospitable environment for so long.”