Researchers Found Signs of Life in a Lake Deep Beneath Antarctica

According to a news report from Nature, an ice-covered lake in Antarctica is teeming with bacterial life.

The southernmost continent of our planet, Antarctica, is generally considered an inhospitable wasteland of ice and snow but recent research shows that there is much more to it than the extreme environment. The researching team found colonies of bacteria in a subglacial lake, called Lake Mercer, which is 600 kilometers away from the South Pole. Scientists consider this discovery a massive breakthrough for the search for extraterrestrial life, especially for Mars, as the Mars Express Spacecraft of the European Space Agency found signs of a subterranean lake of liquid saltwater on the red planet, last year.

In December 2018, polar scientists drilled a 1000-meter-deep borehole towards Lake Mercer in the hopes of finding some signs of life in Antarctica. The early analysis of the obtained water samples indicates that all those efforts were worth every bit of them because they contain around 10,000 bacterial cells per millimeter. Although it is just 1% of the usual number found in the Open Ocean, this is an extremely positive sign for a water body, buried deep beneath the glacier of Antarctica. John Priscu, the Lead of the research who is a Professor of Polar Ecology at the University of Montana, mentioned that these high levels of bacterial life in such a dark lake mean that we may find microscopic animals (tardigrades, crustaceans, etc.) in Antarctica. He said,

“We saw lots of bacteria — and the [lake] system has enough organic matter, you would think, to support higher life-forms. We are really going to get a good look for higher organisms, like animals … but that won’t be done for another couple of months.”

Whillans Lake

Lake Mercer is not the first subglacial lake to be found in the West Ice Sheet of Antarctica. In 2013, Priscu led a team which discovered high levels of bacterial life in an 800-meter-deep lake called the ‘Whillans Lake’. According to a theory proposed by scientists, these bacteria are consuming the organic deposits laid down by photosynthesizing organisms, some 10,000 years ago, when these buried lakes were a part of the Open Ocean. Similarly, the presence of life in such a hostile environment, like Antarctica, increases the possibility of life in other areas of our Solar System like moons of Jupiter and Saturn.

Findings

The researching team came back from their camp on the West Ice Sheet of Antarctica to the Antarctic Base at McMurdo Station last week. During their stay at the camp, they used hot water and drills to open a borehole down to the buried lake of liquid water. Priscu mentioned that the scientific sampling was stopped twice for widening the borehole, which was kept open for about 10 days. He elaborated that they bored around 1,068 meters of ice to obtain -0.65^o C water, which was about 15 meters deep at that point. They came back to the base with 60 liters of subterranean water. In addition to that, they also collected a 5-meter sediment core from the lake for their research, which is the deepest sediment core ever extracted from the West Ice Sheet of Antarctica.

Sandwiched Ecosystem

Priscu seems very hopeful that the study of these sediment cores will allow scientists to improve their understanding about the West Ice Sheet of Antarctica for the past tens of thousands of years. He explained that they used a number of cameras and a remotely-operated underwater vehicle (ROV) to take images of the buried Lake Mercer. He believes that there are more than 400 buried lakes in Antarctica which form a unique ecosystem of sandwiched (between the frozen rocks of continental crust and the thick ice shelf) liquid water. He referred to that by saying,

“I’ve been proposing that the entire ice sheet is a big wetland, with rivers and lakes — and some of the rivers, they span an area the size of the Amazon, though with not as much water. Here you’ve got 70 percent of the world’s freshwater — it just doesn’t make sense that there is no life under there. And now we’ve proven that there is, we have transformed that view.”

Signs of Life on Mars

He concluded the research by connecting this discovery to the search for life on Mars. He is quite sure that any form of life below the frozen surface of Mars follows the same patterns as the buried lakes of Antarctica. He talked about that in the following words:

“The new knowledge that our research has provided on subglacial environments, particularly the fact that they harbor a diverse microbial assemblage, will provide us with information on the type of life that may have existed on Mars.”                 

You can have a look at this amazing discovery in the following video: