Antarctic icefish are uniquely adapted to life in the extreme conditions of the Southern Ocean. Waters surrounding Antarctica are unlike any other, they are isolated, very cold, have large amounts of dissolved oxygen, and have low numbers of competing animals. Because of this unique environment, the icefish have evolved with some interesting traits. They do not have a swim bladder, and they spend much of their time near the ocean floor. To help them survive in the very cold waters, they have antifreeze proteins in their blood and body that keep their cells from freezing. Because of the high oxygen content in Antarctic waters, the icefish are able to survive with lower amounts of hemoglobin, the protein that carries oxygen to the rest of the body, than other fishes. |