FIELD 01Antarctic notothenioid fish live in seawater cold enough to freeze ordinary fish blood.
FIELD 02Their answer is not a thicker coat. It is antifreeze glycoproteins circulating through body fluids.
FIELD 03These proteins bind tiny ice crystals and keep them from growing into lethal structures.
FIELD 04One origin story is especially strange: the AFGP gene appears to have evolved from a pancreatic trypsinogen-like gene.
FIELD 05Cold turned a digestive enzyme ancestor into a survival system for an ocean.
A fish survived Antarctica by editing an old digestive gene into antifreeze.