It's rare that you get to see Nature play out at this level right in front of you. Recently in Yellowstone National Park in the parking lot of Grand Prismatic Overlook, a tourist watched firsthand as a grizzly bear and a bison fought to the death.

Just a warming: The video below may be hard to watch for some. But remember, this is Nature at its rawest, and how it functions in the wild everyday away from cellphones and cameras.

This is also a great reminder that you should also always carry bear spray, even if you're visiting sites in Yellowstone that are heavy-trafficked with lots of people around.

More Fun Yellowstone Pictures