Why Do We Yawn?

We yawn a lot when we’re tired or warm, and sometimes we even yawn just because we see other people yawning! But why do we yawn in the first place? ---------- Love SciShow Kids and want to help support it? Become a patron on Patreon: ---------- Looking for SciShow elsewhere on the internet? Facebook: Twitter: Tumblr: Instagram: SOURCES: https://ac.e