Bird Sings With Its Feathers!

Bird sings with its feathers! "...But when the nine feathers closest to the special feathers were still attached to the ligaments, they vibrated at around 1500 hertz, harmonized with the club feathers, and amplified the volume of the sound."

Thanks to Chelsie for passing on this really fascinating article.

http://news.nationalgeographic.com/news/2009/11/091111-birds-sing-feathers-wings.html