Even grade schoolers know that the Earth's crust is made up of tectonic plates, continent-sized chunks of rock that drift around our planet's surface ever so slowly.
But what causes all that drifting in the first place?
If you think it's the molten rock flowing inside the Earth's mantle, that's only half of the story. For the rest of the explanation, check out the latest video from the YouTube series Minute Earth above.
"Some of Earth's plates, it turns out, are pulling themselves," series co-creator Henry Reich says in the video. "When an ocean plate collides with another ocean plate--or a plate bearing the thick crust of continental land masses--the thinner of the two plates bends and slides under the other. As the edge of the seafloor sinks into the mantle, it pulls on the plate behind it."
Catch his drift?