The Keel-Billed Toucan

Let'ts talk about this enormous, brilliantly colored beak. Averaging around 12-15 cm (4.7-5.9 in), it's about 1/3 of its total length and although it's bill is very large it only weighs a mere 380-500 g (13-18noz). It is actually a spongy, hollow bone covered in keratin, a very light and hard protein.