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Comment by paws | Hacker News Reader

The Greenland shark is pretty unusual.

* Eating it has a deleterious effect on sobriety [1].

* It's also the most toxic shark meat out there. [ibid]

* Female Greenland sharks take 150 years to reach sexual maturity (no word on the gestation period).

The study also shows that Greenland shark females don’t reach sexual maturity until around 150 years old — suggesting that a century of heavy fishing could wipe out the entire species, says Bushnell.

[1] https://en.wikipedia.org/wiki/Greenland_shark#Greenland_shar...

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> It's also the most toxic shark meat out there.

Is that innate or related to the longevity? Other species could just die for they get to that level of toxicity.

Some turtles can live in excess of a hundred years. If they were toxic, surely some tribal community in the South Pacific would've figured that out by now.

Some quick googling didn't turn up much on turtle toxicity other than we seem to be more concerned about us poisoning turtles than them poisoning us. Probably with good reason.

The toxicity comes from trimethylamine oxide (TMAO) which decomposes to trimethylamine (TMA), a neurotoxin. TMA is the compound that produces the odor most associated with rotten fish and it's a very common metabolite found in many different animals (human gut and surface bacteria can produce it too).

The Greenland shark and other ocean life have nervous systems and livers that are better adapted to handling higher concentrations of TMA because it plays an important role in regulating cellular osmosis, which is critical for both salt and fresh water animals. While this may be loosely related to their extraordinary lifespan, it's much more likely that this is an old adaptation from an ancestor species that is irrelevant to their longevity.

It also tastes really really horrible. Thus you eat it with copious amounts of vodka to clear the taste.

https://en.wikipedia.org/wiki/Greenland_shark#Greenland_shar...

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