Why don fish freeze in the Arctic/Antarctica?
Ecologists drool over Antarctica. It’s an ideal place to study evolution, they say. This is partly because the continent’s harsh environment has contributed to the evolution of an abundance of elegant biological adaptations. Life forms running the gamut—from bacteria and fish to plants and birds—have figured out ingenious ways to survive the continent’s frigid, dry climate and relentless winds. Meet the Notothenioids, a group of more than 120 marine fish species, most of which are native to Antarctic waters. Antarctic Notothenioids have remarkable proteins in their bloodstream that prevent them from freezing. These “antifreeze proteins”, as they are commonly known, bind to tiny ice crystals in their bodies, inhibiting further growth. Arctic Cod (Boreogadus saida) Arctic cod (Boreogadus saida) (click for a larger image) © Dr. Christopher Zimmerman, ISH To survive the frigid waters of the Arctic Ocean, the Arctic cod—a genetically unrelated fish to the Notothenioids—developed an antifree
