3 ms·

After reading the article it seems they don't really know why we yawn.

• prawn 12y ago
  I think that's been true of every "why we yawn" article I've ever read. Maybe it just relates to the jaw making sure that at various points it's fully opened, for whatever reason.
  • derefr 12y ago
    Related to that idea: I've heard the suggestion that development of dementia is accelerated by (unreplaced) loss of teeth in old age. As in, when you stop chewing and just start taking your food by liquid, your brain stops working as well, possibly because it's now suffering chronic under-oxygenation on top of everything else. This, along with the chewing gum/migraines connection, seems to suggest the motion of the jaw has a lot to do with brain function. My personal hypothesis: given that the jaw specialized from the fusion and hardening of gills, perhaps the brain still expects it to perform gill-like functions in regularly "pumping" oxygen upward.