Well-Adapted, Complex Lifeforms Thriving Under Massive Volumes of Ice in Antarctica, Study Shows

Scientists studying Antarctica are starting to find thriving vast networks of well-adapted and complex life forms beneath the continent's enormous amounts of ice.

Antarctica's ice is divided into two categories: sea ice and land ice. When the Southern Ocean's upper layers freeze over, sea ice is created. Since the ice cover is seasonal, the majority of this ocean ice melts away in the summer.

As soon as the ice melts, photosynthetic algae blooms have been seen in these areas. But up until recently, it was frequently believed that the dense sea ice blocked all light from penetrating the layers beneath before this seasonal change.

But according to recent findings, phytoplankton blooms-a type of photosynthetic algae-can develop and even flourish before the ice begins to melt.

Thriving Phytoplankton

The majority of aquatic life is based on phytoplankton, which also fosters the development of other complex life forms. The Antarctic Ocean's frozen surface is home to vast areas of these photosynthetic life forms, according to research.

Christopher Horvat, the lead author of the study, said that finding these blooms raises important new queries about the food webs that might exist beneath the ice in Antarctica and helps to refute the idea that areas under sea ice are unpopulated.

The study spearheaded by Horvat was published in Frontiers in Marine Science.

He added that about 5 million sq km of the Southern Ocean's under-ice region could be covered by the blooms.

Separate sheets of packed ice make up the sea ice in the Southern Ocean. Small pockets of open water permit light to pass through between these sheets, enabling photosynthesis.

Thick Ice Shelves

Huw Griffiths, one of the marine biogeographers from the British Antarctic Survey, explained that Since the sea ice is typically only three to ten feet thick, some light can also pass through and directly reach the surface waters below.

Nevertheless, life has also been found in places that have never been exposed to the sun.

Land ice, the second type of Antarctic ice, makes up the majority of ice shelves. They are created when massive ice slabs are forced from the land and onto the ocean's surface. These slabs can sometimes be thousands of feet deep, unlike sea ice.

Griffiths and his team found complex marine life forms on a large rock on the seafloor 3,000 feet below an Antarctic ice shelf in 2021, which was presented in their study and published in Research Gate.

Life in Ice Shelves

He claimed that very little was known about the life found beneath the floating ice shelves of Antarctica. The current body of knowledge is based on a small number of records from boreholes that were drilled through the ice shelves, even though ice shelves cover about a third of the continental shelf or about 1.5 million square kilometers.

Griffiths added that most of what is known today comes from brief video clips or photographs covering a very small area rather than the small glimpses provided by these holes into the life that exists on the seafloor and in the water column.

He continued to say that according to current theories on the types of life that could exist beneath ice shelves, all life becomes less common the farther away it is from sunlight and open water.

Griffiths pointed out that small mobile scavengers as well as predators, like fish, worms, jellyfish, or krill, have been discovered in these habitats in earlier studies. They discovered the first-ever evidence of a community on a hard substrate deep beneath an ice shelf, which is likely made up of sponges and other animals that feed on filters.

Read also: River Found Under Antarctica Accelerates Ice Loss as Global Temperatures Rise 

Subglacial Microbial Species

As you travel further inland in Antarctica, you will find a hidden kingdom of subglacial rivers and lakes that are teeming with life. The third-largest lake on the continent, Lake Whillans, which is located 2600 feet underneath the West Antarctic Ice Sheet, was discovered to have about 4,000 various bacterial species in 2014.

Clusters of shrimp-like creatures were discovered in June by New Zealand researchers in an underground river that runs underneath the Ross Ice Shelf at the southernmost tip of the continent.

Together, these findings show how varied the various life forms are beneath the Antarctic ice.

More than Just Microbes

According to Griffiths, animals that live deep beneath ice shelves must be adapted to survive in water that can be as cold as -2.2 degrees Celsius. Similar to deep-sea animals, these animals would also need to be able to adapt to small amounts of food. These creatures are hundreds of kilometers away from the nearest sources of fresh phytoplankton and daylight.

Similar ecosystems may exist in other frozen landscapes as a result of these adaptations.

Griffiths also said that The finding of complex animal lifeforms-more than just microbes-in such harsh environments raises the possibility that complex life could exist outside of the Earth on frozen planets and moons, like Jupiter'sGanymede, Europa, and Callisto, where liquid water is present beneath the massive icy surface, Newsweek reports.

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