Harvard evolutionary biologist Dan Lieberman is the scientist whose work reshaped how we understand running. His research on human evolution helped popularize the idea that we're born to run, that our bodies, from our toes and tendons to our oversized glutes, are uniquely adapted for endurance. In this conversation, he joins Zoë and Brendan to explore what running reveals about being human.

This week's featured race is the Naughty Hog 100k, 50k, 25k, 10k, and 5k! Dec 20. Register now!

We dig into why ultrarunning is evolutionarily bizarre but still deeply natural, what persistence hunting really looked like, and how belly fat, treadmills-as-torture-devices, and even the barefoot craze all tie into our running story. It's part science lesson, part reminder that while we didn't evolve for nipple tape, running is still one of the most human things we do.

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