Fish Adapt to Icy Water

Fish have certain adaptations, like blood with built-in antifreeze, to survive in the Antarctic.
© John Weller

This shadowy fish, Trematomus bernacchii, is well adapted to the ice-cold water of the Antarctic: its blood comes equipped with natural antifreeze. This is a necessary adaptation because the surrounding water averages minus 1.8 degrees Celcius, just above the freezing point of saltwater.