Cat videos abound, but they rarely explain. They’re  adorable and amusing snippets of cats climbing curtains, pouncing on balls and hiding in drawers.

Why do they do those things? Who knows?

Tony Buffington knows, or he knows a lot more than we do. He’s a well-known veterinarian, professor and “cat guru,” and his knowledge provides the script for an animated TED-Ed video titled, “Why do cats act so weird?”

It’s cute in its own way, and it acts as a sort of CliffsNotes for all the other cat videos that you never waste time at work watching. The pouncing? Cats evolved to “stalk, pounce, kill and eat,” and they’ve still got that instinct. The hiding? Cats long were prey as well as predator, and so they learned how to escape by squeezing into strange spots.

And purring, the purpose of which remains a mystery, happens at a frequency that “can promote tissue regeneration.” So if your cat sleeps on your face, the video suggests, it just might be healing your cheek muscles.

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