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Deepest fish ever caught on camera off Japan

bbc.co.uk

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Re: Deepest fish ever caught on camera off Japan

#2
> Likewise, their approach to food - they are suction feeders and consume tiny crustaceans, of which there are many in trenches.

I remember James Cameron’s dive and the main life pictured was crustaceans. I’ve also read they are a significant amount of life in underground aquifers [1] was crustaceans, which also had blind reptiles which also fed on crustaceans and had transparent skin similar to those snailfish. I’m curious what makes them so unique to flourish in these sorts of places.

[1] https://www.americanscientist.org/article/creatures-of-the-d...

Re: Deepest fish ever caught on camera off Japan

#3
If you ever wondered how they survive the pressure, from wikipedia:

TMAO (Trimethylamine N-oxide) is found in the tissues of marine crustaceans and marine fish, where it prevents water pressure from distorting proteins and thus killing the animal. The concentration of TMAO increases with the depth at which the animal lives; TMAO is found in high concentrations in the deepest-living described fish species, Pseudoliparis swirei, which was found in the Mariana Trench, at a recorded depth of 8,076 m (26,496 ft).

Re: Deepest fish ever caught on camera off Japan

#4
post #3

If you ever wondered how they survive the pressure, from wikipedia: TMAO (Trimethylamine N-oxide) is found in the tissues of marine crustaceans and marine fish, where it prevents water pressure from distorting proteins and thus killing the animal. The concentration of TMAO increases with the depth at which the animal lives; TMAO is found in high concentrations in the deepest-living described fish species, Pseudolipar…

Neat, the wiki for that fish:

https://en.wikipedia.org/wiki/Pseudoliparis_swirei

> Compared to shallow-water snailfish, Pseudoliparis swirei has several unusual adaptions for its dark and high pressure habitat, including transparent skin that lacks pigment, certain organs and eggs that are enlarged, the muscles are thinner, the ossification of its bones (notably the skull) is incomplete, it appears to have little or no ability to see, there are mechanisms that allow proteins in its body to still function, and differences in the cell membranes for maintaining their flexibility.

Re: Deepest fish ever caught on camera off Japan

#5
post #3

If you ever wondered how they survive the pressure, from wikipedia: TMAO (Trimethylamine N-oxide) is found in the tissues of marine crustaceans and marine fish, where it prevents water pressure from distorting proteins and thus killing the animal. The concentration of TMAO increases with the depth at which the animal lives; TMAO is found in high concentrations in the deepest-living described fish species, Pseudolipar…

An interesting case of evolution. In theory the first populations to become fixed for an allele or allelic combination that results in even a small increase in TMAO would be able to access previously untouched feeding grounds and flourish for some time.

Re: Deepest fish ever caught on camera off Japan

#6
post #4
post #3

If you ever wondered how they survive the pressure, from wikipedia: TMAO (Trimethylamine N-oxide) is found in the tissues of marine crustaceans and marine fish, where it prevents water pressure from distorting proteins and thus killing the animal. The concentration of TMAO increases with the depth at which the animal lives; TMAO is found in high concentrations in the deepest-living described fish species, Pseudolipar…

Neat, the wiki for that fish: https://en.wikipedia.org/wiki/Pseudoliparis_swirei > Compared to shallow-water snailfish, Pseudoliparis swirei has several unusual adaptions for its dark and high pressure habitat, including transparent skin that lacks pigment, certain organs and eggs that are enlarged, the muscles are thinner, the ossification of its bones (notably the skull) is incomplete, it appears to have little or…

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Re: Deepest fish ever caught on camera off Japan

#7
post #3

If you ever wondered how they survive the pressure, from wikipedia: TMAO (Trimethylamine N-oxide) is found in the tissues of marine crustaceans and marine fish, where it prevents water pressure from distorting proteins and thus killing the animal. The concentration of TMAO increases with the depth at which the animal lives; TMAO is found in high concentrations in the deepest-living described fish species, Pseudolipar…

Fun fact: the (in)famous Icelandic "rotted shark" (hákarl) food is rotted/fermented in order to remove the toxic TMAO (and urea):

https://en.wikipedia.org/wiki/H%C3%A1karl

Re: Deepest fish ever caught on camera off Japan

#9

> At 8km down, they are experiencing more than 80 megapascals, or 800 times the pressure at the ocean surface. Is this somewhat a coincidence or is this the beauty of the metric system?

This is rounding. 8km would actually be 80304.7 kPa. So not as beautiful as you imagine.

Re: Deepest fish ever caught on camera off Japan

#10
post #9

> At 8km down, they are experiencing more than 80 megapascals, or 800 times the pressure at the ocean surface. Is this somewhat a coincidence or is this the beauty of the metric system?

This is rounding. 8km would actually be 80304.7 kPa. So not as beautiful as you imagine.

I’m guessing the salinity of the water might affect the pressure?
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