An increase of just 2 degrees centigrade could devastate “anti-freeze” fish in the Southern Oceans. Nototheniods is a species of fish that uses glycoproteins as an anti-freeze to survive in the extreme cold of the Southern Ocean. The fish are a major food source for whale, penguins and seals.
Nototheniods flourished and diversified into over 100 distinct varieties as the waters around the Southern Ocean cooled around 40 million years ago, leading to a mass extinction of fish suited to warmer temperatures.
The Southern Ocean around Antarctica is one of the most rapidly warming areas on earth.