Claim: A duck's quack doesn't echo, and nobody knows why.
Analysis: Please note, you won't find this claim made in any scientific journal or textbook. You will find it repeated in such dependable venues as email trivia lists and fruit drink bottle caps reason enough for skepticism.
The obvious logical question, the one neither asked nor answered by those who tout this absurd factoid, is: why wouldn't a duck's quack echo? What could there possibly be about the sound a duck makes that uniquely exempts it from physical laws that apply to all other such sounds, e.g., a dog's bark, a cat's meow, or a lamb's bleat?
The logical answer is: nothing.
For those for whom logic isn't enough, the claim that a duck's quack doesn't echo is empirically disproven by acoustical engineers here.
Sources and further reading:
- Fun Facts About Ducks
About.com: Birding/Wild Birds
- Is It True that a Duck's Quack Doesn't Echo?
Ask the Experts, PhysLink.com
- Is It True a Duck's Quack Won't Echo?
The Straight Dope by Cecil Adams, 22 May 1998
- A Duck's Quack Doesn't Echo?
University of Salford: Accoustics, Audio and Video
- Science 'Quacks' Urban Duck Myth
CNN, 9 September 2003
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