It was the absence of feathers that got conservation biologist Thor Hanson thinking about the significance of them. Hanson was in Kenya studying the feeding habits of vultures, and he noticed the advantages that vultures had relative to other birds because of their bare, featherless heads.
"Having lost their feathers allows [vultures] to remain much cleaner and more free from bacteria and parasites and disease," Hanson tells Fresh Air contributor Dave Davies.
Recently, I was listening to a new tribute album covering the songs of Fleetwood Mac, and thought once again how dreadful most tribute albums are: They don't add much to the legacy of the artists being saluted, while inadvertently freezing vital old music in an amber of sentimentality. Then I turned to When I'm President, an album of new songs by Ian Hunter.