Ancient Ecosystem Discovered Beneath Antarctic Glacier
Scientists have found life in an ecosystem trapped underneath a glacier in Antarctica for nearly 2 million years. The microbes, they suggest, are surviving the dark, oxygen-free waters by drawing energy from sulfur and iron. The findings provide insight into how life may have survived "Snowball Earth"--periods when some scientists speculate that the planet was entombed in ice--and hint at the possibility of life in other inhospitable environments, such as Mars and Jupiter's icy moon Europa.
Researchers have found microbial life surviving in the most unusual places: the depths of cold and dark oceans, seething geothermal vents, and the deepest layers of permafrost. And ever since scientists discovered Antarctica's dark and mysterious subglacial lakes in the late 1960s and early 1970s, they've wondered if microbes could make a life for themselves there too. But the challenges of drilling through kilometers of ice and concerns about contaminating these pristine lakes have curtailed previous efforts to find out.
Blood Falls, a small, saltwater outflow from Taylor Glacier's subglacial lake in Antarctica's Dry Valleys, offers an alternative. The lake sits beneath 400 meters of ice and trickles out at the glacier's end, painting an orange stain across the ice as its iron-rich waters rust upon contact with air. The subglacial lake was originally part of a marine fjord system that became trapped as Taylor Glacier enclosed it between 1.5 million and 2 million years ago. Its sporadic outflow allows researchers to explore the lake without drilling or risking contamination of the isolated environment.