Gabriel Melo-Santos studies Araguaian river dolphins in Brazil — his work has revealed that the species is much chattier than we’d previously known, and could potentially help us better understand the evolution of underwater communication in marine mammals. He plays some of the recordings he’s made of the dolphins, explains how he managed to study the elusive creatures thanks to their fondness for a certain riverside fish market, and discusses how the study of their vocalizations could yield insights into how their sea-faring relatives use their own calls to maintain social cohesion.

If you enjoy this show, please visit www.patreon.com/mongabay to pledge a dollar or more to keep it growing. Mongabay is a nonproft media outlet, so all support helps.

We love reviews, so please find the reviews section of the app that delivers your podcasts and say what you like about the Mongabay Newscast, and how we can improve. Thank you!

Also, please invite your friends to subscribe via Android, Apple Podcasts, Google Podcasts, Stitcher, TuneIn, Spotify or wherever they get podcasts.

Thank you! And please send thoughts, questions, or feedback about this show to [email protected].

Get full access to Planet: Critical at www.planetcritical.com/subscribe