In bestselling author Susan Casey’s third book, she explores the intimate relationship between humans and dolphins.

One of the stories that inspired bestselling author Susan Casey’s new book on the intricate world of dolphins, Voices of the Earth, is almost too beautiful to be believed.

A biologist named Maddalena Bearzi was studying a group of dolphins off the coast of Los Angeles when she noticed something strange. The “pod” (group of dolphins) had just landed upon a herd of sardines. They were about to start feeding—something that usually transfixes the whole group—when one, unexpectedly, darted off.

In moments, the rest followed, swimming full speed out to sea. When she reached them, three miles offshore, the pod had a formed a circle—in the middle of it, a girl’s floating body. Very near death, the girl had a plastic bag with her identification and a suicide note wrapped around her neck. With the dolphins help, she was saved.

“I still think about and dream about that cold day,” Bearzi wrote of the sighting. “And that tiny, pale girl lost in the ocean and found again for some inexplicable reason, by us, by the dolphins.”

Our inexplicably intimate relationship and longtime fascination with dolphins provides a backdrop for Casey’s third book. From bizarre 1950s scientists to a community of dolphin worshippers, it’s an eye-opening look at the world below the sea.

I’ve looked into the eyes of white sharks and you see this incredible creature that’s adapted for 400 million years that’s adapted into its niche, but you don’t see someone looking back at you necessarily. With dolphins, there’s someone looking back at you. That’s the shocking thing.

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CLICK HERE for her book, "Voices in the Ocean," on Amazon.com.