I think I found scientific proof that skunks are at the top of the food chain. I've seen bears attack wolves, mountain lions, elk and bison and win just about every time. I've never seen a bear successfully take down a skunk including this big guy that got schooled.
WARNING: Viewer discretion is advised. It may not be for everyone. The video captures wildlife doing what it does, surviving and fighting. This bear and this bison fight each other and it is all caught on camera.
If you have a security camera anywhere in the western United States, there's at least a chance you'll see a bear on it at some point. One Colorado family learned that a nearby bear really liked their camera a lot.