These Crows Are More Clever Than Non-Human Apes When It Comes to Building Compound Tools

Let's say there is a hundred dollar bill wedged behind a bookshelf just beyond your reach, and beside the shelf is a set of TinkerToys. Even a toddler could probably snap together a few of the sticks to fish the bill out. But what about an animal? One especially smart crow species seems to have figured out this...