A recent study published in the journal Frontiers in Marine Science about unexpected animal life far beneath Antarctica’s floating ice shelves.
At a distance of 260km away from the open ocean, the researchers found out the existence of stationary animals attached to a boulder on the seafloor. The geologists used hot-water equipment to drill the borehole through more than half a mile of the Filchner-Ronne Ice Shelf, on the southern edge of Antarctica’s Weddell Sea with their cameras lowered down.
They had expected the seafloor to be mud, but were dismayed when they hit a boulder, which meant they couldn’t get the intended sediment samples. But to their surprise, the camera showed colonies of “stationary” animals attached to the rock – probably sponges and related sea creatures.
It’s thought both types of stationary animals are types of sponges or are related to sponges, but scientists did not expect to find them beneath the ice shelf, in pitch-blackness and hundreds of miles from the coast.
Dr Huw Griffiths, marine biologist and lead author of the study, said that the stationary animals are like sponges and potentially several previously unknown species.
“This discovery is one of those fortunate acc.id.ents that pushes ideas in a different direction and shows us that Antarctic marine life is incredibly special and amazingly adapted to a frozen world,” the biogeographer said in a separate statement.
After lowering the sediment corer through the borehole, the scientists then lowered it through about 1,600 feet of seawater below the floating ice shelf.
Small mobile animals such as shrimp and crustaceans called sea fleas have been seen before beneath ice shelves, but no one expected to see stationary animals like these. “The only things you would expect to find … are things that can wander around and find food,” he said. “Whereas if you’re st.uc.k to a rock and you’re waiting for food to come to you, then the one bit that comes past this year could go past you.”
The discovery appears to go against all previous theories of what kind of life could survive in such an ex.tre me condition.
“We have no idea what species these animals are. We don’t know how they are coping with these ex.tre me conditions. And the only way we are going to be able to answer those questions is to come up with a new way of investigating their world,” added Griffiths.
The bloblike protrusions seen in the right of the video are clearly a type of sponge, while the stalked creatures on the left are similar to some other sponges found near the Antarctic. There are also indications other animals may be fixed to the boulder, such as tube worms, stalked barnacles, or hydroids, which are related to jellyfish.
In order to survive, the organisms would have to feed on floating material from other animals or plants, because it is impossible for plants to photosynthesize in the sunless seawater. While the boulder is located about 150 miles from the ocean, the direction of the currents beneath the ice shelf suggests the nearest plant life is up to 1,000 miles away, Griffiths said.