The Insane Biology of: The Greenland Shark

Greenland sharks represent the longest-living vertebrate on Earth, with individuals potentially exceeding 500 years of age and reaching sexual maturity only after 156 years, growing at approximately 1 centimeter per year.

Greenland sharks and related spiny dogfish possess among the highest recorded cellular concentrations of trimethylamine N-oxide (TMAO), enabling survival in extreme Arctic conditions where temperatures reach -2°C and pressures exceed 290 atmospheres at 2,900-meter depths.

Greenland shark flesh contains dangerous toxins causing intoxication symptoms including hypersalivation, vomiting, explosive diarrhea, convulsions, and potentially death in animals consuming large quantities, with sled dogs becoming “shark drunk” after eating shark meat.

Approximately 98.9% of Greenland sharks host parasitic copepods (Ommatokoita elongata) latching directly onto eyeballs, with some sharks carrying multiple 6-centimeter parasites dangling from both eyes like hair blowing in current.

Greenland sharks possess dense concentrations of tiny black pores called ampullae of Lorenzini covering their snouts, mouths, and head tops, enabling detection of electrical fields generated by living organisms.

Greenland sharks possess disproportionately enlarged olfactory bulbs—brain regions processing smell—compared to other sharks, with these structures representing the only brain components exceeding relative size expectations given their overall small brain-to-body ratio.

Greenland sharks function as apex predators despite maximum swimming speeds of only 3 kilometers per hour, successfully hunting agile prey including cod, squid, seals, and occasionally whales through methods still debated by scientists.

Greenland sharks possess distinctive upper and lower tooth sets creating a unique bite pattern functioning like a giant hole punch, leaving perfectly circular wounds on prey too large to swallow whole.

Greenland sharks possess the largest genome sequenced among all shark species, containing approximately 6.5 billion base pairs compared to humans’ 3 billion, with over 60% composed of transposable elements or “jumping genes.”

Greenland sharks occupy the entire Arctic water column from surface ice to bathypelagic zones at 2,900 meters near the Mid-Atlantic Ridge, traversing pressure gradients from 1 to 290 atmospheres without physiological constraints affecting bony fish.

Greenland sharks demonstrate extreme metabolic reduction reflected in 3 kilometers per hour maximum swimming speeds and 1 centimeter annual growth rates, exhibiting metabolic rates slower than tectonic plate movement (plates drift apart at 2 centimeters annually).