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Earth Science

Cetaceans Able To Focus Sound For Echolocation 25

Rambo Tribble writes A recent study from Denmark has determined that porpoises, dolphins and whales can focus the sounds they make, described as "clicks and buzzes", when hunting. This appears to exceed even the capabilities of bats. One researcher described the ability as, "like adjusting a flashlight." The BBC offers approachable, and illustrated coverage.
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Cetaceans Able To Focus Sound For Echolocation

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  • Oh yeah? (Score:4, Interesting)

    by Rei ( 128717 ) on Tuesday March 31, 2015 @10:34AM (#49379303) Homepage

    Cetaceans Able To Focus Sound For Echolocation

    Well crustacians are able to focus sound for murder [wired.com] . Beat that, cetaceans!

    • Humans have learned to focus sound too. We've already gone the cetacean/bat route [wikipedia.org], and are now working merrily on the crustacian's methods. [wikipedia.org]

    • by azav ( 469988 )

      Yeah, dolphins too.

      They stun flounder with sound pulses.

      Sweet, huh?

      Well, unless you're a flounder.

    • Re:Oh yeah? (Score:5, Interesting)

      by The Grim Reefer ( 1162755 ) on Tuesday March 31, 2015 @12:27PM (#49379805)
      I didn't RTFA, but I though this was already known. Dolphins can also stun and kill prey using sound . Mantis and Pistol shrimp, obviously, generate sound in a different way.

      It's been a while since I've studied them, but I think they can generate a force equal to a .22 caliber round with those sound waves.

      There are two types of Mantis shrimp attacks. The "spearers" and "smashers". The smashers have the fastest known attack of any animal known to us at the moment, and until recently the fastest known voluntary motion of any animal. Their clubbing appendages accelerate over 10,000g. Even if they don't directly strike their prey, the shock wave of the bubbles (created by cavitation) collapsing will kill their prey. If they don't miss, they first get hit by the shrimp and then again by the shock waves.

      Mantis shrimp also have the most complex eyes of any known animal. Over all a really cool critter. I've kept them in aquariums, and they adapt well and will learn to recognize you after a short period of time and shed their shy nature. But they can be a nightmare if they end up in an aquarium as an unwanted hitchhiker. They usually kill the most expensive inhabitants first.

  • Hasn't this been known for some time?

    I've seen footage of hunting dolphins and whales herding fish into "sonar corrals" and then eating them, and I though I'd heard that the dolphins et al can focus their sonar to fight off things like sharks.

    Maybe I'm missing something, but I thought it had been established for a very long time that these things have really fine control over their sonar and can do all sorts of stuff with them.

    Is this actually something new? Or am I just reading this wrong?

    Surely if I know

    • by tomhath ( 637240 )
      As I read it this study concludes that they not only focus the sound, but they can modify the sound cone at will. Narrower when farther away from their prey, open it up as they get closer to keep it in the beam.
      • Well, having seen the videos of dolphins herding fish into a swirling snack-bar using their sonar, and have seen the explanation of them changing their sonar output.

        They have a huge chunk of their brain dedicated to doing this stuff, and I thought they could even stun fish with it.

        I'm not saying I could do it, but I got the impression this is stuff we've already know they can do.

    • by PPH ( 736903 )

      Hasn't this been known for some time?

      I think so. Research dating back a few decades has associated cetacean melons [wikipedia.org] with the echolocation function, including some species ability to shape this organ. The purpose of such shaping has probably been understood, as some advanved sonars use similar techniques for beam forming and impedance coupling.

  • What did they do, look up the wikipedia article?
    http://en.wikipedia.org/wiki/A... [wikipedia.org]

    Or maybe this Encarta article from 2000
    "The echolocation sounds of toothed whales, produced in their nasal passages, are focused into a narrow beam as they pass through the melon, a waxy, lens-shaped body in the forehead. The echoes are received by the lower jaw and pass through oil-filled sinuses to the inner ear, which is insulated from the skull by a foamlike pad that cuts out irrelevant noise. Upon closing in on their prey,

    • by ceoyoyo ( 59147 )

      Did you read the article? They measured how their porpoises have control over the focus.

      • Yes I did read the article and the idea that something can aim and focus it's primary means of imaging seem intrinsic to that ability, much like different types of animals that can see visible light with their eyes can aim and focus them

        • by ceoyoyo ( 59147 )

          The ability to focus an eye is a relatively specialized adaptation. There's also this thing in science about not making groundless assumptions.

          • Yes, and from the Encarta article that I linked:
              "are focused into a narrow beam as they pass through the melon, a waxy, lens-shaped body in the forehead"

            So, there is your focusing, and apparent scientific understanding of it in 2000
            The linked article is a summary, what other in depth knowledge was brought forward by their study, that it can be aimed by turning the head?

    • by rossdee ( 243626 )

      Well scientists did some research and found out something that has been known for ages.

      In related news, japanese scientists have discovered that whales still taste good, but they still need to do more 'research'.

  • How many of you know what cetaceans are, because of Star Trek IV? [imdb.com]
  • You can navigate in the dark.

  • He could improve our Ki Ai :)

  • It just seems like an obvious finding... like... birds can control which way they move in the air when they fly...

    Really?

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