Where the Mute swans do their grooming and preening, there is always a profusion of white feathers, large and small, stiff and downy. I grabbed this one because I liked the way it showed the constituent parts of the feather.

Rather than repeat what others have so ably published, I thought I’d just post the pretty pictures here and, if you want to learn more, you can check out this particularly good post (with excellent illustrated drawings to aid their explanations) on The Cornell Lab website.