[HN Gopher] Deepest fish ever caught on camera off Japan
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Deepest fish ever caught on camera off Japan
Author : mywacaday
Score : 99 points
Date : 2023-04-01 17:10 UTC (5 hours ago)
(HTM) web link (www.bbc.co.uk)
(TXT) w3m dump (www.bbc.co.uk)
| ericrallen wrote:
| 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/
| terlisimo wrote:
| 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 Love You", "Just Read The Instructions" and "A
| Shortfall of Gravitas".
|
| https://theculture.fandom.com/wiki/List_of_spacecraft
| andrewflnr wrote:
| There's definitely an MSV Pressure Drop on that page, under the
| list of ships in _Hydrogen Sonata_. :)
| rowanG077 wrote:
| So what exactly does this incredibly tangential information add
| to this article? Seriously. I'm getting fed up with hackernews
| discussions spiraling into low quality tangents.
| Kaibeezy wrote:
| Ah, thought you were talking about _Tangents_ , the Greg Bear
| short story collection.
| bmitc wrote:
| 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?
| sixQuarks wrote:
| I'm wondering the same thing. You can see their fins flopping
| around as if it's regular depths
| RicoElectrico wrote:
| 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...
| mytailorisrich wrote:
| I've found a 2014 article by the BBC that explains why fish are
| not expected to survive beyond about 8,000-8,500m:
|
| https://www.bbc.com/news/science-environment-26423203
| Waterluvian wrote:
| > 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?
| elorant wrote:
| Every ten meters pressure raises by one atmosphere. So I'd say
| it's just a coincidence.
| Ekaros wrote:
| I think it is just that gravity happens to be 9,81 m/s^2.
|
| On other hand 1kg being equal to 1 litre of water is by design
| in metric system.
|
| Other happens stance is that pressure on surface is about 101
| 325 pascals.
|
| So things work out that way...
| dakial1 wrote:
| This is rounding. 8km would actually be 80304.7 kPa. So not as
| beautiful as you imagine.
| Waterluvian wrote:
| I'm guessing the salinity of the water might affect the
| pressure?
| [deleted]
| dmix wrote:
| > 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...
| bobthepanda wrote:
| I would imagine it is the extreme pressure. At that kind of
| depth you either need a really strong body and small surface
| area (tiny crustacean) or a gelatinous body where that doesn't
| matter (snailfish). Those are probably disadvantageous at lower
| pressure environments. (I'm curious how molting would work at
| high pressures though, since the crustacean would lose its
| shell.)
|
| as far as blindness, there's not really visible sunlight
| reaching there, so sight probably doesn't do a lot, and
| eyeballs are squishy.
| Retric wrote:
| Creatures living in the deep simply equalize their internal
| and external pressures and don't feel the pressure as some
| kind of weight they need to withstand.
|
| This is why when you bring them to the surface quickly they
| die from the sudden decrease in pressure. As to eyes
| bioluminescence is common in the deep and nothing would
| bother if nobody had eyes.
| nntwozz wrote:
| 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).
| fallingknife wrote:
| Is this why they expect this fish is near the depth limit? Does
| this mechanism stop working at higher pressures?
| transcriptase wrote:
| 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.
| crazygringo wrote:
| Fun fact: the (in)famous Icelandic "rotted shark" (hakarl) food
| is rotted/fermented in order to remove the toxic TMAO (and
| urea):
|
| https://en.wikipedia.org/wiki/H%C3%A1karl
| Kaibeezy wrote:
| So what's natto's excuse?
| Mistletoe wrote:
| >Chef Anthony Bourdain described fermented shark as "the
| single worst, most disgusting and terrible tasting thing" he
| had ever eaten.[2]
|
| Ok that's saying something.
| ldhough wrote:
| I tried a ~1x1cm cube of it when I was in Iceland... that
| assessment is pretty spot-on.
| dmix wrote:
| 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.
| undersolved5 wrote:
| Very cool. the wiki for that other fish, the shallow water
| snailfish, Amblystomopsis.
|
| According to Wikipedia, the Pseudoliparis amblystomopsis is a
| species of fish that belongs to the family Liparidae. Here
| are some key facts about the shallow water snailfish:
|
| The shallow water snailfish is found in the Pacific Ocean,
| specifically in the Kuril-Kamchatka Trench, which is one of
| the deepest parts of the ocean.
|
| Despite its name, the shallow water snailfish is actually
| adapted to live at extreme depths, with individuals having
| been found at depths of up to 7,500 meters (24,600 feet).
|
| The shallow water snailfish is a small fish, typically
| measuring between 12 and 15 centimeters (4.7 to 5.9 inches)
| in length.
|
| This fish has a soft, gelatinous body and lacks a swim
| bladder, which helps it to survive at high pressures in the
| deep sea.
|
| The shallow water snailfish is a predator, feeding on small
| crustaceans and other fish that live in the deep ocean.
|
| Because of its extreme depth range and unique adaptations,
| the shallow water snailfish has attracted the interest of
| researchers studying deep sea biology and physiology.
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(page generated 2023-04-01 23:01 UTC)