Frigid Polar Regions Teeming With Life
Earth's two ice-covered polar oceans may be the most inhospitable places on the planet, but more than 12,000 species of animals have been found there, according to new research released at the annual meeting of the American Association for the Advancement of Science here.
Remarkably, at least 235 of these species live in both the North and South poles and nowhere else - despite the 11,000-kilometre gap.
"One hundred years ago, Antarctic explorers like Scott and Rutherford saw mostly ice," said Victoria Wadley of the Australian Antarctic Division. "In 2009, we see life everywhere."
Wadley is one of over 500 scientists from 25 countries participating in the "Census of Antarctic Marine Life" survey which saw 18 major research voyages during the International Polar Year (2007-2008) that just concluded.
Scientists have thus far identified 7,500 animals in the Antarctic and 5,500 in the Arctic oceans. Total global marine life is estimated at 230,000-250,000 species. To obtain this new data, researchers took samples from nearly one million locations. Those places include seafloors exposed to light for the first time in as much as 100,000 years when ancient ice shelf lids melted and disintegrated in recent years.
While the analysis of all samples is not yet complete, it is expected that the Antarctic will win the total species count, suggests Bodil Bluhm, a researcher at the University of Alaska. While both are bitterly cold regions of ice and snow, they are also very different.
"The Antarctic is a continent with an ocean around it, while the Arctic is an ocean surrounded by land like the Mediterranean Sea," Bluhm said in an interview.
Of the two, the Antarctic is far larger and open to the rest of the oceans, perhaps explaining the higher level of biodiversity, she suggests.
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