"Frogs do for the night what birds do for the day: They give it a voice. And the voice is a varied and stirring one that ought to be better known." — Archie Carr
© John Netherton, Clyde Peeling's Reptiland
Green tree frog, Hylid cinerea, with throat pouch inflated
Frogs were the first land animals with vocal cords: they have been singing for 180 million years. With its mouth closed, a frog pumps air back and forth across its vocal cords. Many male frogs have vocal sacs-pouches of skin that fill with air. These balloons resonate sounds like a megaphone, and some frog choruses can be heard from a mile away.