In addition to the anemones, the scientists saw fish who routinely swam upside down, the ice shelf serving as the floor of their submarine world, as well as polychaete worms, amphipods and a bizarre little creature they dubbed "the eggroll", a four-inch-long, one-inch-diameter, neutrally-buoyant cylinder, that seemed to swim using appendages at both ends of its body, which was observed bumping along the field of sea anemones under the ice and hanging on to them at times.
The anemones themselves measured less than an inch long in their contracted state--though they get three to four times longer in their relaxed state, Daly said. Each features 20 to 24 tentacles, an inner ring of eight longer tentacles and an outer ring of 12 to 16 tentacles.
After using hot water to stun the creatures, the team used an improvised suction device to retrieve the animals from their burrows. They were then transported to McMurdo Station for preservation and further study.
Because the team wasn't hunting for biological discoveries, they were not equipped with the proper supplies to preserve the specimens for DNA/RNA analyses, Rack said. The specimens were placed in ethanol at the drilling site and some were later preserved in formalin at McMurdo Station.
Many mysteries remain about the creatures, the scientists report. Though some sea anemones burrow into sand by using their tentacles or by expanding and deflating the base of their body, those strategies don't seem feasible for hard ice. It is also unclear how they survive without freezing and how they reproduce. There is no evidence of what they eat, although they likely feed on plankton in the water flowing beneath the ice shelf, Daly said.
Rack said a proposal is being prepared for further study of this unusual environment, using a robot capable of exploring deeper in the ocean and further from the access hole throu
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