Okay, but what's it like as a bird at the top of the world?

E29. Standing at 11,000 feet, lungs burning, Scott watched birds go about their afternoon in the exact thin air that had nearly taken him out. This week he sits down with Dr. Chris Witt, evolutionary biologist at the University of New Mexico and curator of birds at the Museum of Southwestern Biology, who has spent his career figuring out how birds make a living in the thinnest air on Earth. From the hummingbird blood that rewrites itself to match a mountainside to a five-pound coot that has no business existing, this one is about the birds thriving where our bodies would quit.

In this episode:

• Why a single Andean slope can stack dozens of hummingbird species right on top of each other, each locked to its own band of elevation
• How the same oxygen-grabbing protein keeps evolving the same way, over and over, in a pattern so predictable it runs in reverse
• The record-holders pulling off things up high that sound like they shouldn't be possible

Chris doesn't just tell us about these birds, he shows us, so you may want to watch this one.

All audio, video, and images in this episode are either original to Okay, But... Birds (© Okay Media, LLC) or used under license/permission from the respective rights holders. Bird media from the Macaulay Library is used courtesy of the Cornell Lab of Ornithology as follows:

• House Finch audio contributed by William R. Fish, ML12932
• Giant Coot audio contributed by Steven L. Hilty, ML56377