Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Why do we yawn

  1. Apr 27, 2007 #1


    User Avatar

    hey just wondering

    why do we yawn when we are tired ? Whats the body's aim in making us yawn ?
  2. jcsd
  3. Apr 27, 2007 #2

    jim mcnamara

    User Avatar

    Staff: Mentor

  4. Apr 27, 2007 #3
    this is my own personal observation so there's no science or research behind it... but I've always noticed that yawning feels more like stretching than breathing for oxygen. We always stretch our muscles when we just wake up or have been passive for a long time (like our back and neck and legs), these are also the times we most likely yawn... could yawning simply be a way of stretching those internal muscles and jaw muscles?
  5. Apr 27, 2007 #4


    User Avatar

    I learned how to yawn at will or keep myself from yawning if I wish it. How common is that? I found it helpful for pressurizing my head when I lived on top of a mountain and had to drive up and down it everyday.
  6. Apr 30, 2007 #5


    User Avatar

    hum that sounds coherent

    and also does contradict Mk's message

    sometimes u really feel like u wanna stretch, and u can stop urself from doing it
    you can also strecth when u want to

    for yawning seems a bit the same, except its a bit harder to control it


    IF only humans yawn THEN

    it has to give an advante over an human who doesnt/cant yawn
    because every human on earth yaws

    this means that during our evolution, those who didnt yawn must have had at least a small disvantage


    ' same thing , but with the related animals, thus might be really complicated coz we would be going more back in evolution

    END IF
    Last edited: Apr 30, 2007
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Why do we yawn
  1. Why do we age? (Replies: 6)

  2. Why do we die? (Replies: 9)

  3. Why do we age? (Replies: 3)

  4. Why do we yawn? (Replies: 6)

  5. Why do we Sleep? (Replies: 6)