12/24/2023 0 Comments Translucent fishThe discovery provides insight into what kind of complex but undiscovered life might inhabit the vast areas beneath Antarctica’s ice shelves-comprising more than a million square kilometers of unexplored seafloor. “You get the picture of these areas having very little food, being desolate, not supporting much life.” The ecosystem has somehow managed to survive incredibly far from sunlight, the source of energy that drives most life on Earth. “I’ve worked in this area for my whole career,” he says-studying the underbellies where glaciers flow into oceans. Powell spoke with me via satellite phone from the remote location on the West Antarctic Ice Sheet, where 40 scientists, ice drillers and technicians were dropped by ski-mounted planes. “I’m surprised,” says Ross Powell, a 63-year old glacial geologist from Northern Illinois University who co-led the expedition with two other scientists. The spot sits 850 kilometers from the outer edge of the ice shelf, the nearest place where the ocean is in contact with sunlight that allows tiny plankton to grow and sustain a food chain. The remote water they tapped sits beneath the back corner of the floating shelf, where the shelf meets what would be the shore of Antarctica if all that ice were removed. The animals inhabit a wedge of seawater only 10 meters deep, sealed between the ice above and a barren, rocky seafloor below-a location so remote and hostile the many scientists expected to find nothing but scant microbial life.Ī team of ice drillers and scientists made the discovery after lowering a small, custom-built robot down a narrow hole they bored through the Ross Ice Shelf, a slab of glacial ice the size of France that hangs off the coastline of Antarctica and floats on the ocean. “We do spend a lot of time exploring down there, so I can say with some confidence that they’re quite rare.Stunned researchers in Antarctica have discovered fish and other aquatic animals living in perpetual darkness and cold, beneath a roof of ice 740 meters thick. In his 30-year career, Mr Robison says he has only seen these 15cm-long fish alive maybe eight times. Their tactic may be to swim up to siphonophores and nibble on the small prey snagged in their tentacles, using the transparent shield to protect their green eyes from stings.īut encountering barreleyes in the wild is not easy. He thinks this canopy probably helps protect their eyes as they steal food from among the stinging tentacles of siphonophores - animals that float through the deep sea in long, deadly strings, like drift nets.īarreleyes have been found with a mix of food in their stomachs, including siphonophores’ tentacles, as well as animals that siphonophores feed on, including small crustaceans called copepods. “It had this canopy over its eyes like on a jet fighter,” he said, referring to the transparent front part of the barreleye’s body, which had been torn off all the specimens he had previously brought to the surface. Seeing a barreleye alive in the deep, Mr Robison saw something else that scientists had previously missed. This means the fish can track prey drifting down through the water until it is right in front of their mouth. “Suddenly the lightbulb lit and I thought ‘A-ha, that’s what’s going on! They can rotate their eyes," he said. “It always puzzled me that their eyes aimed upward, but the field of view did not include their mouths,” Mr Robison said.īut, after years of only seeing dead, net-caught specimens, Mr Robison and colleagues finally got a good look at a living barreleye through the high-definition cameras of a remotely operated vehicle. Mr Robison was initially mystified that their eyes seemed fixed upwards on the small spot of water, right above their heads. The barreleye’s tubular eyes are extremely sensitive and take in a lot of light, which is useful in the inky depths of the twilight zone. It helps barreleyes to get a clear view of the animals trying to erase their shadows Their eye pigment allows the fish to distinguish between sunlight and bioluminescence, says Bruce Robison, deep-sea biologist at the Monterey Bay Aquarium Research Institute in California.
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