Quote Originally Posted by bikerz
Sarah - how do you know things like this?

School field trips to Audobon centers and the like.

The birds gorge themselves til they are so full they can't fly. So if a predator comes, their defense is projectile vomiting. Their feet get filthy from rooting around in carcasses, so they pee on them to clean. They have to feathers on their heads for basically the same reason - they are digging around in dead bodies to eat, so the skin head stays cleaner.