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Infrasound, Elephants and Earthquake Detection

mediareport writes "Science News offers a timely antidote to simplistic mumbo-jumbo about the "mythical power" of animal earthquake detection. Anyone intrigued by reports of possible tsunami-avoidance behavior in Sri Lankan wildlife will enjoy this detailed examination of the latest research into low-frequency sound. Elephant rumblings that produce Rayleigh waves are now under serious study for the first time, while others are designing "highly unusual" experiments to test infrasound sensitivity in humans."

7 of 34 comments (clear)

  1. Animals don't win Darwins by Anonymous Coward · · Score: 5, Funny

    I'm sure there was lots of infra-whats-a-ma-gig going on, but regardless of those factors, what it comes down to is that animals just aren't as stupid as humans.

    When confronted with an unusual, confusing situation, they get the fuck out. Whether it was the vibrations, the noise, or the distant sea swell, doesn't matter, they got the fuck out.

    Humans who feel planet earth is one great big disney park in which they have the right, if not the obligation, to experience *all* the rides, wander down the quickly receding waterline to check it out.

    I suppose it could be valid to think of earth as a disney park, so long as you remember that a large number of the attractions are named "death". If you are too blind to notice that on your way to the shiney new thing..... well.. then I've got a darwin for you.

    (this is mainly directed at the forgein tourists on the (now dry) sea bed starely motionlessly at the wave)

    1. Re:Animals don't win Darwins by dasunt · · Score: 4, Interesting

      I'm sure there was lots of infra-whats-a-ma-gig going on, but regardless of those factors, what it comes down to is that animals just aren't as stupid as humans.

      When confronted with an unusual, confusing situation, they get the fuck out. Whether it was the vibrations, the noise, or the distant sea swell, doesn't matter, they got the fuck out.

      That's loser speak. ;)

      What is better for Og: Avoiding the sharp rock that cut him? Or figuring out how to use that sharp rock to cut others?

      Avoid fire like the rest of creation? Or use it to keep him warm and build better spears to kill others?

      Og thinking that, like all other predators, a healthy, adult mammoth shouldn't be messed with? Or scream and taunt the mammoth to the point where, in order to escape this mad creature, the mammoth tries to flee, forgetting about the large cliff...

      Sure, Og's actions lead to a high deathrate amoung Og's kin. But a few Ogs later, the rest of the clan is much better off.

    2. Re:Animals don't win Darwins by JanMark · · Score: 3, Interesting

      (Warning: non native writer.) Also, most animals can outrun humans. As I understand it, tsunami's can be outrun if you run over 20km per hour. Clearly a lot of big mamals can run faster than that. So that combined with the fact that animals usually do not go investigate how far the sea retracted, makes (bigger) animals byfar more tsunami restistant than humans. I would like to point out however that humans are very successfull multiplying wise. Does anyone know if we outnumber any mamal population (even before we start destroing their habitats)?

      --
      -- (:> jms cs.vu.nl (_) --"---
    3. Re:Animals don't win Darwins by R2.0 · · Score: 3, Insightful

      There is a difference between constant, repeatable threats, otherwise known as risk, and random, large scale events.

      The first human reaction to danger was always to get out of Dodge. But if the danger was repeatable and comprehendable, it got dealt with. If tsunamis happened on a weekly basis, we'd be surfing on them, not dying by the metric ton.

      --
      "As God is my witness, I thought turkeys could fly." A. Carlson
  2. Dead fishes by helioquake · · Score: 4, Interesting

    I wondered about those fishes that died ashore after the tsunami...

    The sound wave indeed propagates through water about 1400km/h, much greater than the propagation speed of tsunami wave at this time (~1000km/h). So the fishes most probably have "heard" the low freqency wave. I'm sure no fish can outswim the tsunami, but I'm a tiny bit surprised to see so many of them got stranged in land.

    I know the physics of waves, but have little experience in ocean current under sea. Would tsunami wave actually whirl up and down so fast that deep ocean fishes get dredged up fast and get knocked out before dying ashore? Or do they simply get left behind waves and asphyxiate to death?

    1. Re:Dead fishes by Meetch · · Score: 5, Insightful
      Hmmm... I would put it down to fish generally not being particularly bright outside of their day-to-day survival instincts, and as they are generally spread out, not needing to respond to such major events as a tsunami for the species to go on. They'd stay in their usual habitat, and if that local habitat goes, then the inhabitants go with it. Occasionally they'd ride a current, especially if given no choice. If they get washed ashore, bad luck.

      What I'd be more interested in is if any, and if so how many, larger sea creatures were dumped ashore. (I believe there were whale beachings in the general vicinity within that general window, but AFAIK it's just coincidental).

      I'm no marine biologist, so anyone with facts that support or shoot down my ideas are quite welcome to do so.

  3. Could it be ionospheric disturbance? by helioquake · · Score: 3, Informative

    Could it be ionospheric disturbance?

    There is an on-going research to forecast earthquakes via detecting ionospheric disturbances (can't find a good article now...it has to do with the detection of a very-remote FM radio signal that could only be detected when anomalous disturbance occurs in the ionosphere. An initial finding was done while amateur astronomers were monitoring FM radio signal for meteor detection). Maybe animals can detect minute changes in the terrestrial electro-magnetic field, I wonder?