Scientists Discover Freshwater Hidden Beneath Antarctic Ice, Defying Belief That It Was Completely Frozen
Antarctica continues to surprise experts, as researchers found a thriving ecosystem under one of the continent's frozen lakes. Lake Enigma was long thought to be frozen solid by experts, but examinations undertaken a few years ago showcase a different story, Live Science reported. Marine scientists uncovered a layer of fresh water inside the icy exterior and spotted a diverse cast of microorganisms. Findings regarding the astounding ecosystem under Lake Enigma have been published in the journal Communications Earth and Environment.
Researchers analyzed the waterbody with a ground-penetrating radar during an expedition lasting from November 2019 to January 2020. The results indicated that there were around 40 feet (12 meters) of liquid water under Lake Enigma. This did not match the previously held assumptions about the lake at all and therefore the team drilled into the ice. Thereafter they sent a camera inside to get a picture of what exactly was happening inside. The video backed up the results produced by the radar.
The team examined the water to determine its source. As per the salt composition of the water, researchers believe that the water comes from the Amorphous Glacier. As to how the glacier manages to supply the water, experts think that a yet-to-be-discovered underground pathway is at play. More than the water, the finding that truly astounded the experts was the presence of various microbes.
Researchers identified several species of Patescibacteria in the microbial population. The organism's detection was out of the blue for researchers, as they had never seen them in ice-covered lakes. Experts have also never tried to find them, because the high-oxygen condition prevalent in such habitats is not suitable for their survival. This implies that the organism has undertaken some unique adaptations to live in Enigma.
Researchers observed that these microbes accumulated together in different groupings, and formed what is known as microbial mats. All microbial mats were not of the same texture. Some had spikes while others looked like "a crumpled thick carpet, sometimes forming large amorphous tree-like structures up to 40 cm [centimeters, or 16 inches] high and up to 50 to 60 cm [20 to 24 inches] in diameter," according to researchers. Experts further believe that many of these microbes are photosynthetic and hence contribute to the high concentration of dissolved oxygen in the lake.
This discovery is indicative that there is much more biodiversity to explore in Antarctica. "This finding highlights the complexity and diversity of food webs in Antarctic permanently ice-covered lakes, with symbiotic and predatory lifestyles a possibility not previously recognized," the researchers wrote in the study. The finding also has extraterrestrial prospects, as the environment in spots like Lake Enigma is similar to what is found in icy moons like Europa or Enceladus. The organisms found in Enigma could showcase what kind of microbes could thrive in those moons. This is not the first time an icy lake in Antarctica has been discovered housing a community of organisms. Before Lake Enigma, Lake Vida was found hosting a community of bacteria by NASA.