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This is in reference to Could an organism have evolved to kill its prey by shouting at it?

However, most answers here speak towards the brute force side of the equation, measure by it's decibel level. I'd like to redirect the question to give a static Decibel amount (we will say 110, so it's loud but not loud enough to cause the stunning effect) and allow the user to change through a variety of frequencies.

A singer can crack a glass after some trial and error if they hit the right frequency...could a predator use changing frequencies to hunt it's prey?

Hard-science here please.

Edit in clarifications:

  • Whatever prey you feel is best to capture
  • Whichever environment is best suited works, I imagine it'll be a paremeter in some answers
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This question asks for hard science. All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See the tag description for more information.

  • $\begingroup$ This seems related to the recent "resonating sword of doom" question. Also, what did you have in mind for the prey? Is it just one specific species that it can stun, should it be able to stun almost anything, or just whatever you can get? $\endgroup$ – Rob Watts Mar 31 '17 at 21:31
  • $\begingroup$ Also, what sort of environment do you imagine the hunting taking place in? $\endgroup$ – Joe Kissling Mar 31 '17 at 21:32
  • $\begingroup$ Editted in answers for questions above...whatever prey item is most susceptible to the attack and whatever environment that works best in is fine. $\endgroup$ – Twelfth Mar 31 '17 at 21:42
  • $\begingroup$ Since when can a singer crack glass? As far as i know this is not possible using the sound equipment we humans are equipped with $\endgroup$ – BlueWizard Apr 1 '17 at 19:53
  • $\begingroup$ discovery.com/tv-shows/mythbusters/mythbusters-database/… @JonasDralle not the best source...but mythbusters confirmed this one a while back. Its as mucb to do with finding the glasses resounance frequency...but it Works! $\endgroup$ – Twelfth Apr 2 '17 at 23:04
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Yes

It's not well understood but apparently, dolphins can do just that with their sonar. It's speculated that either a pulse of sound or some kind of constant frequency disorients and even sometimes kills their prey.

These speculations are based on the observations scientists. Here is the relevant section from the article:

Marten had noticed before that dolphins close to herring would emit low bangs at the frequency the fish hear best at, and had suggested the bangs were designed to damage the fish's hearing apparatus. He has now taped a dolphin emitting a sequence of low- frequency "bangs" while chasing a fish.

In a further experiment, Marten showed that low sounds with similar acoustic properties to dolphins' clicks disorientated anchovies to the point where they swam in circles, remained still or died. "It could also mess up their schooling," he says.

Meanwhile, Herzing has found evidence of a different strategy. She recorded wild Atlantic spotted dolphins emitting a medium-frequency buzz while searching for prey in sand on the seabed. She says buried eels jumped out of the sand, and either stopped completely or moved sluggishly as if they were stunned, giving the dolphin time to catch them.

This paper and abstract list sound frequency of 196 kHz with an intensity of 10 W/cm². The authors also speculate that whales may have this capability too because their prey is often found in the stomach without signs of struggling while being eaten.

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  • $\begingroup$ Interesting link. Can you add a better summary of it to your answer in case the link dies in the future? $\endgroup$ – Rob Watts Mar 31 '17 at 21:33
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    $\begingroup$ Just a note: water is one thousand times more dense than air. What's possible in water is not necessarily possible in air, and vice-versa. $\endgroup$ – AlexP Apr 1 '17 at 0:08
  • $\begingroup$ @AlexP this is true, but any way you slice it 10w/cm^2 is ton of energy. Though In air that qualifies as a shockwave more than a sound wave. $\endgroup$ – Joe Kissling Apr 1 '17 at 15:34
  • $\begingroup$ Marking this as correct...The dolphins here seem to readily be altering their frequency of their 'sonic assault'. Exactly what I was looking for, thanks! $\endgroup$ – Twelfth Apr 4 '17 at 20:42
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Yes!

To piggyback off Kiplings answer, pistol shrimp also do this underwater:

The animal snaps a specialized claw shut to create a cavitation bubble that generates acoustic pressures of up to 80 kPa at a distance of 4 cm from the claw. As it extends out from the claw, the bubble reaches speeds of 100 km/h (62 mph) and releases a sound reaching 218 decibels. The pressure is strong enough to kill small fish

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  • $\begingroup$ right idea, but not quite what im looking for...we went over killing and stunning with high db levels, but im looking for the same ability using the frequency of the sound and not the volume $\endgroup$ – Twelfth Apr 1 '17 at 5:33
  • $\begingroup$ «same ability using the frequency of the sound and not the volume» a particular frequency alone can’t have the desired effect. You are looking at transferring energy, not just signaling a bit of information. $\endgroup$ – JDługosz Apr 1 '17 at 10:14
  • $\begingroup$ Is a Wikipedia link enough to countbas “hard science”? I think you might need to cite the primary source instead. $\endgroup$ – JDługosz Apr 1 '17 at 10:17
  • $\begingroup$ Ah you're correct, I should have read the OP better, sorry about that. @JDługosz I'll be sure to do that in the future, as this particular answer doesn't seem to be what OP is looking for anwyay. $\endgroup$ – Stephen Schroeder Apr 2 '17 at 14:34

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