Tools, hell. Bats make their own audio amplifiers! Rock on.

Aside from using curled leaves as mechanical amplifiers, the researchers found that the leaves also worked as a megaphone, increasing the volume of sounds emitted from inside the leaves by 1 to 2 decibels (by focusing the sound as it leaves). They also found that because different sound frequencies were impacted in different ways by the shape of the leaves, bat calls heard inside would be nearly impossible for the hiding bats to distinguish between family, friend or stranger.

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