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Researcher Dave Bowden said [scientists] had found more than 30,000 specimens.They are 11,000km apart, but the Arctic and Antarctic Oceans have more in common than scientists ever believed.
Biologists gathering data for a mammoth marine life survey were startled to find more than 200 seemingly identical species living at both poles.
Now DNA from grey whales, birds, worms, crustaceans, and snail-like creatures called pteropods is being tested to find out if the species are really identical.
If so, scientists want to know where they originated and how they ended up living literally a world apart.
The findings have been released by the Census of Marine Life project, as part of a global census of ocean species that will be unveiled in London in October next year.
The information was gathered during sea voyages by hundreds of scientists in 2007 and last year.
Forty-four New Zealanders braved giant waves and the heaviest sea ice in 30 years to gather samples and deep-sea pictures for the project, working through the night for three months aboard the research vessel Tangaroa in the Ross Sea, which is in the Southern Ocean in Antarctica.
At the same time, researchers from other countries were working at the opposite pole under armed guard to protect them from polar bears.
When the New Zealand scientists returned, Niwa researcher Dave Bowden said they had found more than 30,000 specimens, some of which people had never seen before.
Scientists analysing the Antarctic findings for the Census of Marine Life said there was evidence cold-water snails were migrating south to cooler waters as ocean temperatures rose.
They also discovered Antarctica had been acting as a cold incubator for the world's oceans over glacial cycles lasting millions of years. They believe new species of octopus, sea spiders and crustaceans have been evolving in the Antarctic each time the sea ice expands, then migrating to new homes in deep seas further north when the ice melts.
They said about half of the 1 million species of marine life found below the Antarctic Circle were found nowhere else on Earth.
