Don't know much about biology. But I know more than Eric Carle, apparently.
And someone else pointed out to me that the butterfly wings are on upside down. He's not an airplane, he's a moth-- butterfly-- whatever. Butterfly and moth wings are wider on the top and narrower on the bottom. So either his wings are upside-down, or his whole body is upside-down in the picture and what everyone thinks is his head is actually his butt.