Did you know that the Greenland shark, formerly assumed to live solely in arctic waters, has been found as far south as the Gulf of Mexico?

However, a video featuring a Greenland shark off the coast of Brasil shows most likely its nearest relative, the pacific sleeper shark. Just like it, the Greenland shark uses trimethylamine N-oxide (TMAO) as natural antifreeze and to counteract the protein-destabilizing effects of (deep sea) pressure. This makes it possible to adapt to chilling water temperatures of 4 °C or lower, like in arctic waters, but also in deep sea waters all around the world. And it causes toxic shark meat, which doesn’t deter Icelanders from regarding decayed Greenland shark meat as a national dish.

Greenland sharks are born at about 90 cm -35 in- in length and grow only 0.56 cm -1/4 in- per year (proven by tagging), which means that 6 m -21-ft- long specimen could be several centuries old.

The normally sluggish Greenland shark, additionally afflicted with a parasite in its eyeballs rendering it nearly blind, is able to feed from seals, polar bears and caribous as well as fish, seaweed, jellyfish and squid (based on stomach contents). One could assume that it is only a scavenger – if there weren’t eye-witness accounts of Greenland sharks exploding from the shore und dragging Caribous back into the water. They seem to sneak up on napping seals, too.

Sources: herehere and here

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