The Greenland shark is the longest-lived vertebrate known, with lifespans of 272–510 years confirmed by radiocarbon dating of eye lens crystals. It matures at ~150 years, gestates pups for 8–18 years, and lives in deep, frigid North Atlantic and Arctic waters. Its extreme slowness — lowest swim speed for its size — reflects a metabolism tuned to cold, darkness, and pressure. It eats carrion and general prey, poses no threat to humans, and faces conservation risk due to bycatch, late maturity, and low reproductive output.
It lives longer than any other vertebrate — up to 510 years — dated by carbon in its eye lenses.
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Reproduction on geological time
It reaches sexual maturity at ~150 years and gives birth after 8–18 years of gestation.
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Sluggish in the abyss
It lives in freezing deep water (−1.1 to 7.4°C, 100–1,200 m) and swims slower than any fish its size.
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Generalist, harmless, unseen
It eats carrion and whatever else it finds — but never humans, thanks to its remote habitat.
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Worth your time?
Yes. See the whole thing.
4.5/ 5
What works
redefines vertebrate longevity
matches physiology precisely to cold, deep, high-pressure environment
links metabolic slowness directly to lifespan and reproduction
What does not
threaten humans
live in warm or shallow water
reproduce early or frequently
See it if
deep-time biologists
Arctic ecologists
physiological adaptation researchers
Skip it if
divers
beachgoers
anyone expecting dynamic behaviour
Who should see it, and who should skipHide who it is for
The written brief1 min read
What the species is and where it came from
The Greenland shark (Somniosus microcephalus) is a cold-adapted, deep-water shark native to the North Atlantic and Arctic Oceans.
How it works, in terms someone would actually use
It swims at the lowest speed for its size of any fish — sluggish, cold-blooded, metabolically slow — in deep, dark, near-freezing water from 100 to 1,200 metres down.
What it gets right
It gets cold, deep, high-pressure existence right: enhanced rod vision, lateral line reliance, TMAO/urea physiology, and DNA repair all match its Arctic abyssal niche.
What it does not
It does not threaten humans. It does not live in warm or shallow water. It does not reproduce early, often, or quickly.
What it changed
It redefines vertebrate longevity: no other known animal lives longer, and none ties lifespan so tightly to metabolic slowness, cold adaptation, and delayed reproduction.
Who it is for, and who it is not
It is for people who study deep-time biology, Arctic ecology, or extreme physiological adaptation. It is not for divers, beachgoers, or anyone expecting action.
Is it worth your time
Yes — if you want to see how life stretches time itself: a vertebrate that outlives nations, reproduces once in a lifetime, and moves so slowly its gestation spans human generations.
