The science of birdsong - Reader's Digest

It's a sound we're all familiar with—but why do birds sing? And how do they get that perfect pitch? All your questions answered. 
It's a sound we're all familiar with—but why do birds sing? And how do they get that perfect pitch? All your questions answered. 

Nature's Music: The Science of Birdsong eBook : Marler, Peter R., Slabbekoorn, Hans: Kindle Store

The Science of Birdsong

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The science of birdsong - Reader's Digest

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