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Home / Science / Small animals discovered in Lost Lake under 3500 feet of ice in Antarctica

Small animals discovered in Lost Lake under 3500 feet of ice in Antarctica



Scientists drilling in Mercer Lake, a sub-glacial Antarctic lake that is trapped beneath 3500 feet (1 kilometer) of ice, found the carcasses of tiny animals, including the water bears, in a finding described as "totally unexpected." "Discovered.

On December 26, researchers funded by the US National Science Foundation (NSF) managed to melt a hole through the thick ice and underlying water. A report in the journal Nature reported that the Subglacial Antarctic Lakes Scientific Access (SALSA) team has "melted through a huge, frozen river using a high pressure hot water drill."

The water under the ice sheet is hydraulically active In connection with the Ross Sea and the Mercer Lake, a high risk of collapse has been identified with the West Antarctic ice sheet due to global warming. This is only the second time that people have seen the contents of the lake, and the massive scientific operation has been carried out with technologies including "ice-penetrating radar and other remote sensing techniques," as described in the article in Nature.

  Main: Cross section of an artist showing the drilling process to reach the lake below (public domain). Inset: Mercer Lake (CC by SA 3.0)

Main: Cross section of an artist showing the drilling process to reach the lake below (public domain). Inset: Mercer Lake (CC by SA 3.0)

Rediscovering the Ancient Subaquatic Life

The Guardian reported that the scientists had collected mud samples from the bottom of the lake's icy waters and found "tendrils of plants or fungi and photosynthesis residues Algae that lived and died in the area millions of years ago when the Antarctic was much warmer. "Later, researchers discovered crab-like crustaceans and eight-legged tardigrades or" waterbears ", described as smaller than poppies.

David Harwood, a micro-paleontologist at the University of Nebraska-Lincoln, told Nature reporters that the discovery of the animals in the old lake had been "completely unexpected," but the biologists at Lake Mercer really shocked the realization that some of them were affected The beasts were landlubbers.

The scientists know that these ancient creatures inhabited the Trans-Antarctic mountain ponds and streams when the glaciers receded in warm periods 10,000 or 120,000 years ago. However, one outstanding problem is that these crustaceans and tardigrades have inhabited ponds about 80 kilometers from Lake Mercer, and how they got there is not yet clear.

  Tardigrades taken with a scanning electron microscope (CC by SA 2.5)

Tardigrades

[15] shown with a scanning electron microscope (CC by SA 2.5) could provide the DNA with answers to the ancient origins of the creatures

th January, scientists sealed the hole and they believe it will take several years to analyze and test all collected samples. They must test DNA samples from the crustacean carcasses to determine if they are marine or freshwater species. The SALSA team also wants to determine the age of the carbon-doped organic material and will also sequence the DNA of the animals and try to answer how, when and how far the Antarctic glaciers have retreated over the millennia. In 2013, Slawek Tulaczyk, a glaciologist at the University of California, Santa Cruz, was the co-leader of a drilling expedition on Lake Whillans, a subglacial Antarctic lake, 50 kilometers from Lake Mercer.

Tulaczyk, who has studied sediment samples of lakes under the glacial ice since the 1990s, told The Guardian that "such a thing has never been found under the ice." A previous article in Nature reported that the team at Tulaczyk Lake found Whillans they were full of microbes and had no "signs of a higher life" as discovered at Mercer Lake.

The whole idea of ​​the lakes under the frozen Antarctic Antarctic was not considered until the 1990s, when seismic satellite mapping technologies and ice-penetrating radar revealed evidence for subglacial lakes. Almost 400 scientists are now known, all of whom are fed by the base of the ice surface, which, scientists estimate, is only a few millimeters per year. However, this is not caused by global warming but by the release of ambient heat from deep within the planet.

Top Image: Coast of the Antarctic with centuries-old walls in front of glaciers (Sichkarenko_com / Adobe Stock )

By Ashley Cowie


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