back to article You're going to have stop calling people 'cold fish': THIS one is HOT-BLOODED

The world's first warm-blooded fish has been spotted splashing about as bold as brass in Pacific waters, to the delight of Ichthyologists marine boffins – and no doubt of metaphor-busters – around the world. Scientists at the US National Oceanic and Atmospheric Administration (NOAA) have discovered that the opah, or moonfish, …

  1. Anonymous Coward
    Alert

    Warm blooded?

    So, is it an old wives tale (or fishermans tale) that catching a fish on hook and line (like the video) doesn't cause the fish any pain as they are cold blooded. So in this case it does?

    1. Anonymous Coward
      Anonymous Coward

      Re: Warm blooded?

      Of course it is. Poikilothermy is nothing to do with having a functional nervous system. Fish have very well developed external sensors. What they don't have is the ability to cry out, or show emotions.

      Incidentally, this discovery is a wonderful confirmation of the theory of evolution. If something conveys an advantage in a particular environment, we would expect the species using it to adapt by selective fitness of random genetic variance and mutations. We wouldn't expect fish to go "Well, we're poikilothermic, let's just stay out of there." We'd expect some species to adapt as far as possible. And this is just what seems to have happened. Give a lot of genetic monkeys a lot of DNA typewriters, get fish which have become warm blooded by a new route based on existing physiology.

      1. Grikath

        Re: Warm blooded?

        "Fish have very well developed external sensors. What they don't have is the ability to cry out, or show emotions."

        Or even the hardware to "feel" things like "pain" , "existential dread", and al the other things the cuddly hippies try to project onto them. Fish are extremely well-engineered, but emotions are simply not part of the package.

        1. Anonymous Coward
          Anonymous Coward

          Re: Warm blooded?

          "Fish are extremely well-engineered, but emotions are simply not part of the package."

          That's your opinion, and it is as valid as that of James Rose, referenced below.

          Fish show avoidance reactions to negative stimuli. Rose's argument seems to be based on Skinnerian behaviourism - we can't observe "pain" in any humans other than ourselves, so what's unobservable can be regarded as not existing, for scientific purpose. But few of us, other than extreme psychopaths, would regard pain as not existing for other people. And those of us who live with dogs will be very aware of behaviour which shows that they feel something akin to what we feel.

          In human beings, emotions operate at a lower level than consciousness. They are mediated largely by hormonal (or at least chemical) signalling; hormones like oxytocin and serotonin are involved in a lot of emotion. And chemical signalling preceded complex neuronal signalling, in an evolutionary sense. My own feeling is that fish behaviour is more a matter of chemical signalling and "emotion" than complex neural computing. Therefore, when a fish avoids a negative stimulus, it's not unreasonable to describe this in the same terms as our own lower level emotions. By describing fish as "well-engineered" you are making a fundamental category error about the design of fish. They evolved, they were not designed, and they evolved from creatures which used chemical signalling, not digital logic.

          1. Grikath

            Re: Warm blooded? @Arnaut

            If you mean the 2002 paper by James D. Rose as quoted by wikipedia and other sources, his conclusion is the same as mine: Pain, being a psychological phenomenon, needs a psyche to be experienced. And there is no physical evidence whatshowever that fish have actual intelligence, let alone a psyche.

            As far as the engineering goes, I could have used terms like "physically and behaviourally optimised for their niche within the phase space", but as a biologist I tend to appreciate the beasties in the wild as well as on my plate, and "beautifully engineered" is just as applicable, especially since "life" engineers itself against the environment it finds itself in. No need for god-bothering there, as you try to imply.

            1. Anonymous Coward
              Anonymous Coward

              Re: Warm blooded? @Arnaut

              "... but as a biologist ..."

              You may be a biologist, but you also sound like a psychopath. :(

            2. Anonymous Coward
              Anonymous Coward

              Re: Warm blooded? @Arnaut

              ""beautifully engineered" is just as applicable, especially since "life" engineers itself against the environment it finds itself in"

              In one place you want me to agree to a tautology - that pain is psychological so you must have a psyche to experience it (show me a psyche). In another you write "life engineers itself against the environment it finds itself in", which (since engineering is a conscious activity that requires a psyche, in your terms) is engaging in quasi-theological thinking. I'm not doubting that you are a biologist, but I actually don't think you have examined the social conditioning of your thinking about the mind/body problem. (At school we somehow managed to have a biology teacher who was an evangelical Christian, and another one who was a militant atheist. This is probably why even now I'm primed to listen for echoes of creationism in biological thinking. Perhaps I'm overtuned.)

            3. x 7

              Re: Warm blooded? @Arnaut

              "Pain, being a psychological phenomenon,"

              No its not. Its a function of the autonomous nervous system and is a simple reflex action. Put a cat or a mouse on a hot plate and see what happens. Neither have a psyche, but both react as if it hurts.

            4. Triggerfish

              Re: Warm blooded? @Arnaut

              However if you are just quoting Jim Rose, then you are not staying up to date with current opinion, there's plenty of people who have pointed at flaws in his arguments.

              We do not know if fish have a psyche ( you are making the flaw of assuming they do not have one on the judegment of this guys ten year old research.).

              Likewise fish have been known to show varying personalities pufferfish, groupers, sharks all are examples, they have even found some tool using fish, and some quite complex interactions between fish and also other species. All of which argues to some level of intelligence.

              I think you need to do more research.

        2. x 7

          Re: Warm blooded?

          I don't think pain can be described as an emotion

      2. This post has been deleted by its author

      3. P. Lee
        Trollface

        Re: Warm blooded?

        >this discovery is a wonderful confirmation of the theory of evolution.

        and what feature could you find in an animal which would disprove evolution?

        No one has a problem with variation, specialisation and natural selection but all those things, in nature, result from restricting the gene pool of a species. That isn't what most people think of as "evolution."

        The problem with having more DNA typewriters is that you run out of universe before the maths adds up. The "proof" that evolution "works" is that there is stuff around and all other possibilities have been discarded. Everything is proof because the theory is infinitely flexible. Everything will always be evidence of our conclusion, if we've already pre-decided what the conclusion is and we don't have the awkwardness of having to show cause and effect or have anything be demonstrable. Is a fish warm-blooded? That's evidence of evolution. Is a fish warm-blooded? That's evidence of evolution. There is nothing imaginable which could not be attributed to evolution.

        Its an amazing philosophy.

        Materialists run into problems with the mind. If energy/matter are all that exists, then (a) there is no such thing as free will - you are a slave to your biology/chemistry/physics and (b) your thoughts a product of random interactions of the material world and, since they are a product of randomness, are just as likely to be incorrect as correct, including your thoughts on what is right and what is wrong. Since we can deduce that our thoughts are likely to be wrong half the time, it would be irrational to hold a materialist position and claim to be probably correct.

        1. DocJames
          FAIL

          Re: Warm blooded? @ P Lee

          and what feature could you find in an animal which would disprove evolution?

          Well, you'd not find one in an animal (or plant, fwiw) alive today. You'd find an organism that occupied a space that was inconsistent with evolution.

          Like "rabbit fossils in the precambian." R A Fisher's succinct response to how to disprove evolution, dating from the 1920s or 30s. Strangely, despite all the angst over evolution (or more precisely, what it implies about humanity and its place in the universe) nobody has taken up this challenge.

    2. Triggerfish

      Re: Warm blooded?

      The jury is still out on fish feeling pain. Funnily enough because some of the issues is how do you define pain? There's certainly stress indications, and to some degree pain/ or its equivalent makes evolutionary sense I would think.

      This PFK article is pretty good on it.

      http://www.practicalfishkeeping.co.uk/content.php?sid=5436

      1. This post has been deleted by its author

      2. Tom 7

        Re: Warm blooded?

        If you put a hook in a fishermans mouth and drag them around underwater they dont cry out so it cant hurt. They only resist and flail about to make it more fun for the fisherfish.

        1. Eagleon

          Re: Warm blooded?

          Upvoted for fisherfish <3

  2. Swarthy
    Alien

    Full marks for the headline and all, but....

    Should 200m really be considered CTHULHU DEEPS? That would imply that Nessie could be a shoggoth.

    1. Sir Sham Cad

      Re: Full marks for the headline and all, but....

      According to sources (oh, alright, wonkypodiatrist and giggle) R'lyeh lies close to the Nemo Point in the South Pacific. This is pretty much bang in the middle of the Pacific Abyssal Plain which is somewhere between 3650m and 6000-odd metres deep. Cthulhu would be waiting dreaming at roughly 4000m

      Looking up at those wussy Opah that can only handle that mesopelagic fluff.

  3. DJO Silver badge

    Hot blood vs Cold blood

    I thought the definitive differentiation was enzymes, in hot blooded beasties there is just one enzyme to do any specific job but as enzymes are very temperature sensitive a cold blooded critter will be able to make multiple enzymes for any given task, each one effective for a narrow temperature band.

    1. Chris 244
      Boffin

      Re: Hot blood vs Cold blood

      Nope. Central to aerobic metabolism is the TCA or Kreb's Cycle. The enzymes involved are critical to cell function, such core functions tend to be very highly conserved. There is not much difference between us and fish here, and fish do not have multiple sets of TCA enzymes optimized for different temperature ranges. Swapping enzymes can't change the underlying physics: chemical reactions occur more slowly at lower temperatures. That's why even a small boost to core temp is such an advantage for a predatory fish, as it can then outrun both its competition and prey.

  4. Grikath

    The most important question:

    Is there good eatin' on them?

    And yes,they be tasty. :)

    1. RainbowTrout

      Re: The most important question:

      Local restaurant had it on the menu as the weekly special catch a few months ago. Tried to get it but was sad to learn it was sold out.

  5. Little Mouse

    That beastie looks like the kind of thing I used to end up with after leaving El-Fish running overnight...

    1. Gordon 10
      Alien

      Close Encounter

      The poor thing has the same look on its face as abductee's do just before they are probed. Which ironically is just what happened after the photo was taken.

      1. Anonymous Coward
        Anonymous Coward

        Re: Close Encounter

        From the article is sounded more like they cut them apart for study.

  6. Kubla Cant

    Interesting article. I just wish I could stop reading the name of the fish as "oompah".

    1. Bunbury

      You're not alone there. Is it odd that my first reaction was to try and calculate whether it would fit up my jumpah?

    2. This post has been deleted by its author

  7. Greg D

    Do you like fish sticks?

    Oh wait, wrong joke.

  8. Graham Marsden
    Coat

    And I thought...

    ... that sub-headline was a typo for Oprah...

  9. Anonymous Coward
    Anonymous Coward

    In that picture

    Doesn't look like the fish is having much of a good time.

    1. Ken Moorhouse Silver badge

      Re: In that picture

      Don't you mean

      Doesn't look like the fish is having a whale of a time.

  10. PNGuinn
    Joke

    And now for some REAL science...

    Can I be the first to apply for a hefty research grant to discover if there are any warm blooded politicians?

    AND I could charge a tidy sum for the priviledge of manning the harpoon...

    What's not to like?

  11. Tom Maddox Silver badge
    Paris Hilton

    Well, that's great . . .

    . . . but what happens when you stick one in your ear?

  12. P0l0nium

    Not news !!!

    It has been known for years that Tuna fish are warm blooded.

    http://en.wikipedia.org/wiki/Pacific_bluefin_tuna

  13. skeptical i
    Devil

    Opah!

    Not from Greece?

  14. x 7

    I always thought Opah Winfrey was a bit of a cold fish

  15. jmmwill

    They ARE NOT "Warm-Blooded"

    There is a serious logical error in comparing this fish's heat generation with that of "warm-blooded" creatures.

    The observation is that the fish keeps its body temperature five degrees above the water temperature.

    However, "warm-blooded" organisms such as mammals or humans do not maintain a certain temperature above that of their surroundings; they very closely maintain a certain ABSOLUTE temperature, regardless of the surrounding temperature.

    1. This post has been deleted by its author

    2. harmjschoonhoven
      Headmaster

      @jmmwill

      "warm-blooded" organisms such as mammals or humans ...

      "warm-blooded" organisms such as humans and other mammals ...

  16. Martin Budden Silver badge
    Pint

    rete mirabile

    As a homebrewer I can attest to the excellent efficiency of a counter-flow heat exchanger: near-boiling wort entering my plate chiller is cooled to around 20C in just a couple of seconds as it passes through, and the cold tap water flowing in the opposite direction comes out too hot to touch.

POST COMMENT House rules

Not a member of The Register? Create a new account here.

  • Enter your comment

  • Add an icon

Anonymous cowards cannot choose their icon

Other stories you might like