For most of our planet’s existence, the Earth was quiet. The boisterous sounds of life we know today are a recent development, one that the growing field of bioacoustics is helping us understand and interpret. In this episode, we travel to Australia to listen to dolphins and meet the microbes that helped usher in life on the planet.

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Threshold is listener-funded.To keep making this work and sharing it with audiences for free, we have to raise $75,000 by the end of the year — and we’re over 80% of the way there! If you haven’t chipped in yet, consider making a gift today.

We're So Close

This giving season listening matters. To keep making our show, Threshold needs to raise $75,000 by the end of the year — and we’re over 85% of the way there!