Thursday, August 21, 2014

Cold, Dark and Alive! Life Discovered in Buried Antarctic Lake

Antarctica, the coldest place on Earth, teems with microscopic life. Tiny organisms dwell on the ice and live inside glaciers, and now, researchers confirm, a rich microbial ecosystem persists underneath the thick ice sheet, where no sunlight has been felt for millions of years. Nearly 4,000 species of microbes inhabit Lake Whillans, which lies beneath 2,625 feet (800 meters) of ice in West Antarctica, researchers report today (Aug. 20) in the journal Nature. These are the first organisms ever retrieved from a subglacial Antarctic lake. "We found not just that things are alive, but that there's an active ecosystem," said lead study author Brent Christner, a microbiologist at Louisiana State University in Baton Rouge. "If you had to think up what would be the coolest scenario for an ecosystem in Antarctica, you couldn't make this up." [See Photos of Lake Whillans' Drilling Project & Microbial Life] Antarctica has nearly 400 lakes trapped under its ice sheet. Some of them — like Lake Whillans — are connected by rivers and streams. Others are deep, isolated basins like Lake Vostok, where drillers have yet to successfully recover uncontaminated water samples. The new Lake Whillans discovery raises scientists' hopes that these other hidden waterways also carry life.  Drillers broke through to Lake Whillans in January 2013, after years of planning and more than $10 million spent by the National Science Foundation. The team, called WISSARD, used a custom hot-water drill with its own decontamination system. Within a day of pulling out the tea-colored water, tests done in a temporary lab confirmed the lake sparked with life. Researchers returned to the United States with 8 gallons (30 liters) of lake water and eight sediment cores from the lake bottom. Scientists at Montana State University, the University of Tennessee and other institutions parsed out the precious samples, growing cultures of different cell types and sequencing the DNA. The results show evidence for 3,931 species of single-celled life in Lake Whillans. [Video: Life Discovered in Subglacial Lake Whillans]...more 

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