Antarctic fish with 'antifreeze for blood' under threat as oceans become less chilly

By ROB WAUGH

The sailfin plunderfish is a notothenioid: The species evolved 'antifreeze' in their blood millions of years ago, but the trait could prove to be their downfalll

A fish which has used a 'natural antifreeze' to thrive in the Antarctic for millions of years is under threat, scientists say.
The 'antifreeze' glycoproteins in notothenioid fish - known as icefish - enabled them to survive when a global freeze led to a mass extinction of other species around 42 million years ago.
This gave them an evolutionary edge - there are now 100 different species of notothenioids - but is now putting the species, a major food for penguins and seals, at risk.

The fish have thrived in the Antarctic, becoming a major food for penguins and seals, after evolving 'antifreeze' in their blood to survive low water temperatures

The biggest growth in species happened ten million years ago, reports the Proceedings of the National Academy of Sciences.
But Prof Thomas Near, of Yale university, warns that the very adaptations which enabled them to thrive in the cold periods make them particularly vulnerable as the world warms up.
He said: ‘A rise of two degrees centigrade of water temperature will likely have a devastating impact on this Antarctic fish lineage, which is so well adapted to water at freezing temperatures.’

source: dailymail