Nature's Perfect Partners

In the animal kingdom, what do you do if you've got an itch you can't scratch, food you can't get your teeth into or you simply need some home security? Well, you find yourself a partner - and not necessarily someone like you! Hippos are joining forces with fish for a full-body exfoliation. Ravens are inviting wolverines to dinner for some bone-crunching assistance. Bill Bailey introduces these and so many more extraordinary partnerships found in nature.