Several alien-like organisms have been found thriving on a boulder far below Antarctica‘s ice shelf, in one of the planet’s most extreme environments where food, heat and sunlight are almost non-existent.
A team of geologists stumbled upon the colony of sponge-like lifeforms and animals while drilling for sediment cores beneath the Filchner-Ronne Ice Shelf, according to their findings published Monday in the Frontiers in Marine Science journal. They had no intention of looking for life, but they found it through a pure fluke.
Rock-hunters with the British Antarctic Survey cut through 870 metres of ice to get to the water far below, then tried to plunge a drill into the seafloor when they struck a boulder instead.
Scientists dropped a GoPro camera down the hole to investigate the obstruction and were shocked when they pulled it back up to review the footage.
In the video, the GoPro camera falls through the hole and clanks off a boulder before settling on the seafloor with its lens pointed up. The camera is tilted enough to reveal several moss-like organisms and tiny animals growing under the rock — including some with long stalks that wave in the blackness below the ice. Researchers counted 16 sponges and at least 22 unidentified animals on the rock.
The scientists were stunned to find anything alive in the extreme environment below the ice shelf, where conditions are even more unforgiving than in the pitch-black depths of oceans in warmer parts of the world.
“There’s all sorts of reasons they shouldn’t be there,” marine biologist and lead study author Huw Griffiths, of the British Antarctic Survey, told the New Scientist.
“It’s slightly bonkers,” Griffiths added in a separate interview with The Guardian. “Never in a million years would we have thought about looking for this kind of life, because we didn’t think it would be there.”
Deep-ocean creatures survive by feeding on each other, on swirling plankton or on dead plants and animals that fall down from the more well-lit layers of the water column. However, conditions are much more bleak under the ice shelf, where there are few lifeforms to deliver scavenger meals to the layers below.
Nevertheless, the lifeforms on the rock somehow managed to survive with over one kilometre of ice and nearly-empty water overhead, researchers say. The nearest open water is 260 kilometres away, although food would’ve had to come from an even greater distance based on the direction of underwater currents.
Griffiths says the organisms are likely filter feeders that capture tiny bits of organic material from the water. Their mere existence suggests that underwater currents can sweep food across distances that scientists once thought impossible.
“This isn’t some graveyard where a few things cling on,” Griffiths said. “It’s more complicated than we thought.”
The study authors plan to examine the area in more detail in the future, as there might be some never-before-seen species living in the depths below the ice.
“It was a real shock to find them there,” Griffiths said. “But we can’t do DNA tests, we can’t work out what they’ve been eating, or how old they are. We don’t even know if they are new species, but they’re definitely living in a place where we wouldn’t expect them to be living.”