Okay, but what about birds that can't fly?
5/28/202633 min
E24. Flight is the thing we associate most with birds, so what does it mean when a lineage gives it up? Dr. Scott Edwards, Harvard, joins Scott to unpack how flightlessness evolves, why it keeps happening across the bird family tree, and what the genome reveals about how a bird loses the ability to fly.
In this episode you'll hear about:
- How losing flight reshapes a bird's body, from feathers to forelimbs to that one famously enormous egg
- Why the answer wasn't where geneticists expected to find it
- What an extinct giant and a tiny tropical relative can tell us about where moa actually came from
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:
- Falkland Steamer-Duck audio contributed by Maurice A. E. Rumboll, ML4114
- Great Tinamou audio contributed by David L. Ross, Jr., ML57320
Clips
Transcript preview
First 90 secondsScott Taylor· Host0:00
All flightless birds on the planet evolved from flighted ancestors as far as we understand it, right? So even though we think of ostriches and emus as these classic, like, flightless creatures, their ancestors were flighted, which is true of kiwis and even of penguins. The first flightless bird I remember learning about, other than penguins, was the dodo. You know, the cartoon version, round, dopey, a sort of confused turkey with a beak too big for its face, lumbering towards the camera while a Dutch sailor sharpens a knife in the background. The story I got as a kid was basically birds, but worse. They forgot how to fly, they forgot how to be afraid of humans, they got eaten, and now they're a metaphor for being out of date, dead as a dodo. The whole thing felt like a cautionary tale about evolutionary laziness. Almost none of that turns out to be right. The dodo wasn't fat or slow. It was a giant pigeon, active, well-adapted to its forest, and its closest living relative is something called the Nicobar pigeon, which is shockingly beautiful and very much still flying around Southeast Asia. Mauritius was first sighted by Dutch sailors in 1598. By 1681, the dodo was gone, less than 100