The polar oceans are not biological deserts after all.

 

A marine census released recently documented 7,500 species living in the Antarctic and 5,500 in the Arctic, including several hundred that researchers believe could be new to science.

 

Most of the discoveries were simpler life forms known as invertebrates, or animals without backbones.

 

Researchers, for example, doubled the number of jellyfish-like Arctic ctenophore known to science from five to 10. One of those was the size and color of an orange, had bungee cord-like tentacles streaming off it and was living at a depth of two kilometers.

 

"The textbooks have said there is less diversity at the poles than the tropics but we found astonishing richness of marine life in the Antarctic and Arctic oceans," said Victoria Wadley, a researcher from the Australian Antarctic Division who took part in the Antarctic survey. "We are rewriting the textbooks."

 

The survey－which included over 500 polar researchers from 25 countries－took place during International Polar Year which ran in 2007-2008.

 

New technology helped make the expeditions more efficient and productive than in the past. 

 

Researchers used cell-phone-like tracking devices, for example, to record the Arctic migration of narwhals, a whale with a long twisted tooth, and remotely operated submersibles to reach several kilometers down into the oceans to study delicate marine animals that are impossible to collect.