Here's something I don't get: what's the evolutionary advantage of hopping?

Think about it. At some point in evolutionary history, kangaroos and bunny rabbits must have been given a reason to develop hopping muscles and bone structures instead of walking systems.

There must be some advantage to hopping. It wouldn't develop in two totally different species if there wasn't. Does it expend less energy? Is it faster? Is it easier to change direction quickly? I don't know.

Maybe they just do it because it's funny-looking. A hopping world must be infinitely more amusing. A lot of society's problems could probably be solved if everybody hopped around.