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Walking past the park today, I heard a cicada so loud I thought at first it must be some sort of large power tool. How is it that that very small animals like cicadas (crickets, etc.) can make such loud sounds? It seems intuitive that larger animals should be able to make louder sounds, but perhaps:

a) I just fundamentally misunderstand the physics involved

b) A theoretical larger animal should be able to make louder sounds, but cicadas are just extremely efficient, making up for their small size

c) ?

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c) might be 'they can make louder sounds, but usually choose not to'. Blue(?) whales can be heard for thousands of miles underwater. I imagine alerting every lion for thousands of miles isn't a great thing to do if you're an elephant. –  Jeremy Kemball Aug 19 '13 at 14:27
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It is true that the total energy budget for smaller animals should be smaller. Perhaps it's because cicada sounds are spectrally narrow? The total power of the sound might be small, but it's concentrated around a specific pitch. Just a hunch. –  Memming Aug 19 '13 at 14:51
    
Also note that size isn't everything here. Cicadas broadcast at a high frequency because they are moving so fast (which does take up a relatively large amount of energy). If you could get an elephant to move as fast you could probably make some defining sounds, but the energy requirement would probably be to large. –  Atl LED Aug 19 '13 at 19:15
    
I know that "high frequency" affects pitch - does it affect loudness too? –  Oreotrephes Aug 20 '13 at 0:10
    
Yes, since high frequencies have higher energies. Low frequencies can travel further, though. –  Miguel Ángel Naranjo Ortiz Aug 20 '13 at 10:12
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