Beneath the water lies a whole world of sound: snorts, boops, croaks, grunts. Fish, it turns out, have a lot to say, and they’ve been communicating for a long time. In this episode, we take a dive with some of the planet’s oldest vertebrates

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Special thanks to Lauren Hawkins, Miles Parsons, and Tim Lamont for many of the fish recordings. Clara Amorim and Raquel Vasconcelos recorded the Lusitanian toadfish, Herbert Tiepelt recorded the pikeperch percussionist, and Marta Bolgan provided the “unknown kwa.” Additional recordings came from more than a dozen other scientists, many of whom have contributed sounds to the website Fishsounds.