Here's my take, as an animal trainer: for the first 13 seconds, the lioness was looking to stalk/hunt/kill the baby. You can see she's going for the element of surprise. But for the glass, the baby would have been toast. For the rest of the video, she's displaying more of a playful curiosity (which could still have the same outcome, of course). The difference? Cats usually only attack when their prey is facing away from them.
