Folks, your biology teacher was right: Science is cool. This realization is as much a part of growing up as having fewer friends, but who needs friends when you can watch hundreds of thousands of spider crabs marching together under the sea.
If that sounds appealing (welcome to your new life), check out the above clip. It's part of BBC's new Blue Planet II, a sequel to the wildly popular 2001 series. Make sure to watch it with audio, because David Attenborough's British accent trumpeting phrases like, "Around the first full moon of winter an army materializes: spider crabs," really puts the wonder of the ocean in perspective.
The synchronized spider crab shuffle at 0:50 is good comedy, but things get terrifying when they start climbing on top of one another and become a living mound that's "nearly 100 meters long." At times the footage looks more alien invasion than nature doc.