The Alaskan blackfish (Dallia pectoralis), important in the diet of Alaskan
Indians, is an abundant large-mouthed little fish that grows to about eight
inches. The fish freezes solid in the winter, but when spring comes it thaws
out, revives, and is as lively as ever. Another frozen fish is the ice fish (Chaenocephalus
aceratus) of Antarctica, which was not discovered by scientists until the 1930s,
although whalers had told tales of it long before this. The pallid ice fish,
which grows to about two feet long, has crocodile-like jaws and no real blood.
Its pale appearance is due to a lack of red blood cells. Flowing through its
body in place of blood is a colorless plasma that enables the ice fish to
inhabit waters below the freezing point – the plasma is composed of chemicals
very similar to those contained in your car’s antifreeze. Unknown fish with this
adaptation might live in cold unexplored ocean depths that were once thought
uninhabitable.