A colony of iron-breathing microbes has survived for millions of years under an Antarctic glacier, thriving without air or sunlight, Reuters cited researchers as reporting today. The tiny organisms were probably trapped when the sea they were living in became sealed in the ice and they may have survived since then on the decomposing remains of other sea life, the researchers reported in the journal Science. "This gives us some insight into how life survives for extended periods of time in cold, dark conditions," Jill Mikucki of Dartmouth College in New Hampshire, who worked on the study, said in a telephone interview. Such creatures survive in extreme environments on Earth and perhaps on other planets and moons, she said. "I think it can provide some insight into space exploration," she said. Antarctica's Blood Falls are well-known -- a frozen waterfall colored bright red by iron, which attracted attention as early as 1911. It comes from a very slow leak from a pool buried deep beneath the ice, Mikucki said -- a pool teeming with tiny, living cells. They are surviving 2.5 miles (4 km) beneath the ice in a brine loaded with iron and sulfur. "The brine comes out through some kind of crack," Mikucki said. "I got lucky one year and we were able to capture samples while it was actively flowing." She was able to culture living microbes, including Thiomicrospira arctica, which metabolizes sulfur, and Desulfocapsa sulfoexigens, which can live without oxygen. Mikucki said it is not clear how many newly discovered species there may be. "It's a bit like finding a forest that nobody has seen for 1.5 million years," Ann Pearson of Harvard University in Massachusetts, who worked on the study, said in a statement. "Intriguingly, the species living there are similar to contemporary organisms, and yet quite different -- a result, no doubt, of having lived in such an inhospitable environment for so long."
