• Question: why do you yawn????

    Asked by cupcake94 to Amar, Ana, Andrea, Leah, Matt on 18 Mar 2014.
    • Photo: Anastasia Wass

      Anastasia Wass answered on 18 Mar 2014:

      As far as I know there’s lots of theories but no-ones quite sure.
      When we yawn it’s normally because we’re tired. We do this from being little babies all throughout life.
      However have you ever noticed how if one person yawns someone else usualy does to? This is known as an infectious yawn. Yawns don’t become infectious until we’re about 5 or older. Before then we only ever yawn if we’re tired, around or after this age we also yawn if someone else does. This shows part of yawning is a learned behaviour.

    • Photo: Andrea Hanvey

      Andrea Hanvey answered on 18 Mar 2014:

      I know that there’s quite a few theories on yawning, the two I know of are; firstly a physiological theory that the body makes you yawn to draw in oxygen to get rid of excess carbon dioxide in the body. The second theory is an evolutionary one that early man yawned to show his teeth To warn other people off. I know there are other theories out there!

    • Photo: Amar Joshi

      Amar Joshi answered on 18 Mar 2014:

      No one really truly understands why we yawn but there are several competing ideas at the moment.

      Some people think that we yawn when we have too much carbon dioxide in out blood but experiments did not support this idea. Another competing idea is that we yawn to stretch out mouth and tongue to prevent it cramping.

    • Photo: Leah Fitzsimmons

      Leah Fitzsimmons answered on 18 Mar 2014:

      In the last few years scientists have done quite a few experiments to try to figure out the reasons why we yawn. Since all animals and humans do it surely it must have an important function? Well, a current popular idea is that it help our brains to cool down.
      When scientists compared people with warmed heads to those who wore ice packs to cool them down, they found the people with cool heads yawned much less. Scientists have also shown that mice with warmer brains yawn more and that their brain temperature decreases after they yawn.
      There is more detail about current research here: http://www.smithsonianmag.com/science-nature/why-do-we-yawn-and-why-is-it-contagious-3749674/?no-ist

Comments