Census of Marine LifeFinds 235 Common Species at Poles

At least 235 marine species live both in the Arctic and Antarctica, far more than previously thought, according to research by the Census of Marine Life. Although 6,835 miles separate the polar seas, the researchers discovered the same species of cold-water worms, crustaceans, sea cucumbers, and snail-like creatures called pteropods, among others. Scientists suspect that during ice ages, the common species were carried from one pole to the other — most likely from Antarctica to the Arctic — by frigid currents that drop to the bottom of the sea floor and slowly move north. The Census of Marine Life is a decade-long project to catalog the world’s marine species.