There's a video blowing up on Facebook of a kid jumping up and down in front of a bear enclosure at the Nashville Zoo. And a bear on the other side of the glass starts doing it with him.
Also, three professional wrestlers recently went to the San Antonio Zoo, and used a huge rope to play tug of war with a LION. And they couldn't even get it to budge. It's kind of like a dog that won't let go of its toy. But the lion is much stronger