But as the weather gets warmer so does the water, and then some of the predators might be able to live there, threatening animals like the ribbon worms.
The warning comes from a US scientist called Professor Rich Aronson, who explained that when the seas in Antarctica got really cold 35 million years ago, all the predators vanished.
Aronson also said that even a very small rise in sea temperature of just few degrees could be enough to make big changes to the animals that live there.
Images courtesy of the British Antarctic Survey.
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'I helped clean up Antarctica'
