Do you have any interesting videos about animals in the wild?

In this question, a user posted a video showing a bison sacrificing one of its own in order to secure the safety of its herd from an attacking pack of wolves. Or at least, as I understand from the video.
I don’t know much about animals, so I thought this very peculiar. I didn’t know bisons did stuff like that, and now I’m wondering if anyone has any videos about animals in the wild doing weird stuff. Feeding habits, hunting, defense, grooming, fighting for mates, building their homes, anything else… whatever you got. It would be interesting to learn more about the ways of animals. And it can be any animal from anywhere. I would prefer wild animals, but pets are fine, too. Insects also count.
I’m looking on my own on YouTube and finding cool stuff, but I figured I’d ask Fluther, too.