How Did Polar Species Find Their Way to Opposite Ends of Earth?

sand flea picture.jpg

Sand-fleas such as Hyperoche capucinus, are common predators swimming in polar waters. This specimen is about the width of a finger.

Russ Hopcroft, University of Alaska Fairbanks, Census of Marine Life.

Earth’s unique, forbidding ice oceans of the Arctic and Antarctic have revealed secrets to explorers, who were especially surprised to find at least 235 species live in both polar seas despite a distance of more than 7,000-mile (13,000-kilometer) distance in between, the Census of Marine Life (CoML) project announced today.


“The scientists found marine life that both poles apparently share in common include marathoners such as grey whales and birds, but also worms, crustaceans, and angelic snail-like pteropods, the latter discoveries opening a host of future research questions about where they originated and how they wound up at both ends of the Earth,” the CoML said in a news statement.

DNA analysis is underway to confirm whether the species are indeed identical.

Among many other findings, the scientists also documented evidence of cold water-loving species shifting towards both poles to escape rising ocean temperatures.

The discoveries are the result of a series of voyages conducted during International Polar Year, 2007-2008.

The studies by a global network of polar researchers have added substantially to human knowledge about the diversity, distribution and abundance of marine life, with results to be fully detailed in the world’s first Census report, to be released in London October 4, 2010.

“The polar seas, far from being biological deserts, teem with an amazing quantity and variety of life,” said Ian Poiner, chair of the Census Scientific Steering Committee. “Only through the co-operation of 500 people from more than 25 countries could the daunting environmental challenges be overcome to produce research of such unprecedented scale and importance. And humanity is only starting to understand the nature of these regions.”

Census researchers last year established that several octopus types have repeatedly colonized the deep sea, each migration coinciding with retreating Antarctic ice over 30 million years.

Russ Hopcroft, University of Alaska Fairbanks, Census of Marine Life.

“Today they theorize that the Antarctic also regularly refreshes the world’s oceans with new varieties of sea spiders, isopods (crustaceans related to shrimp and crabs), and others as well. They believe the new species evolve when expansions of ice cloister Antarctica; when the ice retreats, they radiate northward along the same pathways followed by the octopuses,” the CoML release said.


The nemertean Pelagonemertes rollestoni, about 1.2 inches (3 centimeters) long, hunts for zooplankton prey that it will harpoon with a dart attached to the tongue coiled within it. It yellow stomach reaches out to feed all parts of the body.

Russ Hopcroft, University of Alaska Fairbanks, Census of Marine Life.

More from National Geographic News:

PHOTOS: Odd, Identical Species Found at Both Poles

PHOTOS: New Deep-Sea Species Revealed by Marine Census

Ocean Life Survey Reveals World of Deep-Sea Creatures


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