I guess there's no one thing that separates humans from the rest of the animal kingdom. Sure, we have opposable thumbs and higher reasoning abilities and pattern recognition and speech and use of tools going for us, but there are other animals that can do some of those things as well.
For my money, creativity has to be up there for uniquely human things. We have a drive to make things and use our imaginations to solve problems. Sometimes that creativity can lead us in odd directions, however.
But even so, you've got to go with it, just like these folks did.