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Deepest fish ever caught on camera off Japan

bbc.co.uk

31–40 of 84 posts

Re: Deepest fish ever caught on camera off Japan

#31

I just recently read the Brilliant Abyss[0] and it was a really interesting look at the deep ocean and the complexity of life down there. If this kind of thing interests you at all, I highly recommend it. I didn’t know much going in, but found it fascinating. [0]: https://helenscales.com/portfolio/the-sea-beneath-us/

I just read this as well, excellent and fascinating stuff! I thought I already knew a lot about “deep ocean life” but most of it was brand new to me!

Re: Deepest fish ever caught on camera off Japan

#32
post #21

What does water "feel" like at that depth? There is a lot of weight felt I guess from the pressure, but is it thicker to swim through in some sense?

Water is incompressible, so I think it should behave similarly. Even viscosity remains within a few precent [1] (Mariana Trench is around 100 MPa) [1] https://www.engineeringtoolbox.com/absolute-dynamic-viscosit...

Interesting. Thanks! Upon doing some searching it seems that the water at the bottom of the Mariana Trench is just 5% more dense. I didn't realize that water was that resistant to being compressed.

Re: Deepest fish ever caught on camera off Japan

#33

DSSV Pressure Drop sounded like a Culture ship name to me so I looked that up. It's not, but the name of the DDSV, "Limiting Factor", is. Apparently they also named their utility boats after Culture ships. To those who don't know: "The Culture" is a... society(?) of godlike AI ships/minds from the series of SF books by Ian M. Banks. SpaceX named their landing barges after Culture ships too, the "Of Course I Still Lov…

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I don't agree that this is low quality, but if you haven't already, maybe upvote the other top level comments? (At time of my comment, this is the top thread on the page.)

Re: Deepest fish ever caught on camera off Japan

#34
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…

Is this why they expect this fish is near the depth limit? Does this mechanism stop working at higher pressures?

Yeah, the cited depth limit of ~8.5km appears to be based on “fish use an osmolyte called TMAO to protect their proteins from pressure, and below 8.5km the concentration of TMAO required is so high that it inhibits cell function”. Apparently crustaceans get deeper by using five different osmolytes at once instead of relying on TMAO. (Info from helpful comment by mytailorisrich in this thread https://news.ycombinator.com/item?id=35403838)

Re: Deepest fish ever caught on camera off Japan

#35
post #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…

Another commenter posted a link to a 2014 article that explains how the fish can survive so deep.

https://www.bbc.com/news/science-environment-26423203

It says that fish use the TMAO protein to protect themselves from pressure. But other organisms use a combination of multiple proteins and that apparently lets them survive higher pressures.

So it seems the fish would basically need to re-evolve how to handle pressure, but in a different way, to be able to go deeper.

Re: Deepest fish ever caught on camera off Japan

#36

I just recently read the Brilliant Abyss[0] and it was a really interesting look at the deep ocean and the complexity of life down there. If this kind of thing interests you at all, I highly recommend it. I didn’t know much going in, but found it fascinating. [0]: https://helenscales.com/portfolio/the-sea-beneath-us/

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Re: Deepest fish ever caught on camera off Japan

#38

I just recently read the Brilliant Abyss[0] and it was a really interesting look at the deep ocean and the complexity of life down there. If this kind of thing interests you at all, I highly recommend it. I didn’t know much going in, but found it fascinating. [0]: https://helenscales.com/portfolio/the-sea-beneath-us/

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Re: Deepest fish ever caught on camera off Japan

#39
post #37

I wonder if this fish will be crucial to the survival of life on Earth, if the climate change gets out of control. I would imagine the conditions at the deepest levels of the ocean won't change much, allowing their natural habitat to continue.

And in fact they’ll thrive as more and more detritus rains from above!

Re: Deepest fish ever caught on camera off Japan

#40
post #29

> 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?

Those factors of 10 don't really look so nice if you use e.g. the binary number system.

Indeed. And the SI defining constants are downright ugly.
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