Scientists utilized clean coring techniques explore the sediments at the bottom of the lake.
According to a news release from the British Antarctic Survey, researchers have discovered 100,000-year-old microbes in the sediments of an Antarctic subglacial lake for the first time. The idea that life forms might live in the lakes hidden kilometers beneath the Antarctic ice sheet has enthralled scientists for years.
However, direct sampling of these cold and dark lakes in the interior of Antarctica requires researchers to overcome several significant technical obstacles. Given these impediments to their research, scientists from the BAS and the Universities of Northumbria and Edinburgh have been looking around the withdrawing margins of the ice sheet for subglacial lakes that are being exposed.
The scientists settled on Lake Hodgson on the Antarctic Peninsula, as it is now covered by only 3-4 meters of ice (at the end of the last Ice Age, this lake was covered by more than 400 meters of ice).
According to the news release, scientists utilized clean coring techniques to explore the sediments at the bottom of the lake. The lake itself is 93 meters deep.
Although the lake was believed to be an extreme environment for any form of life, the sediments at the bottom of Lake Hodgson act as a storage facility for the DNA of the microbes which have resided there for thousands of years. The researchers noted that 3.2 meters deep the microbes discovered most likely date back almost 100,000 years.
“What was surprising was the high biomass and diversity we found,” posits lead author David Pearce of the University of Northumbria. “This is the first time microbes have been identified living in the sediments of a subglacial Antarctic lake and indicates that life can exist and potentially thrive in environments we would consider too extreme.”
“The fact these organisms have survived in such a unique environment could mean they have developed in unique ways which could lead to exciting discoveries for us,” Pearce adds. “This is the early stage and we now need to do more work to further investigate these life forms.”
Some of the life found was in the form of Fossil DNA revealing that many varying types of bacteria reside there, including a number of extremophiles which are species adjusted to the harshest conditions. These species utilize several chemical techniques to keep alive both with and without oxygen at their disposal.
According to the scientists, one DNA sequence was even linked to the oldest organisms known on Earth and parts of the DNA in 23 percent has not been previously characterized.
These research expeditions are important because many scientists think that organisms residing in subglacial lakes, like Lake Hodgson, could contain hints for how life might survive in extreme conditions on other distant worlds.
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