Why Do We Yawn

Why do we yawn If you think the answer is BORing, then maybe your brain s just overheated. Let Hank explain the new thinking behind why we. .. hold on. .. yawn. Excuse me. Help support us by subscribing to our page on Subbable: Like SciShow Want to help support us, and also get things to put on your walls, cover your torso and hold your liquids Check out our awesome products over at DFTBA Records: Looking for SciShow elsewhere on the internet Facebook: Twitter: Tumblr: Thanks Tank Tumblr: Sources: