• Question: why is yawning contagious

    Asked by jimmy to Alan, Ciorsdaidh, Lauren, Leonie, Martin, Neil, Shuo on 9 Mar 2018.
    • Photo: Lauren Webster

      Lauren Webster answered on 9 Mar 2018:

      Yes. A yawn is your body realising that the tiny air sacs in your lungs are full of CO2 and need to be expelled (released). On doing so, if someone is watching you, it causes an involuntary response (not controlled or thought about, just happens) and their brain gets reminded that their air sacs too could be filled with CO2, causing them to also yawn. So yes, yawns are contagious. Did you yawn during or after reading about yawning?!

    • Photo: Neil Keddie

      Neil Keddie answered on 9 Mar 2018:

      You got me reading a bit about this, and some of the theories are fractionating. I liked the one that discussed that it was a sign to other members of your tribe (we’re all neanderthal man with limited language skills) that you were tired, so there was a sense of shared empathy (a lot of others in the tribe might yawn in response back).

      Lauren explained the proper physiology of why your body feels the need to yawn, and if you’re tired thats your body helping prepare you for sleep by getting some more oxygen to help you settle down to get into a resting position.

      And yes, the thought of this question made me yawn too – the same happens to me when i even read the word ‘yawn’ in a book when reading to my kids.

    • Photo: Alan McCue

      Alan McCue answered on 9 Mar 2018:

      Thanks Lauren, I learnt a lot from you answer 🙂

    • Photo: Martin McCoustra

      Martin McCoustra answered on 12 Mar 2018:

      No point in me pitching in… Lauren and Neil have done a good job…

    • Photo: Ciorsdaidh Watts

      Ciorsdaidh Watts answered on 13 Mar 2018:

      Thanks Lauren for the chemistry/biology answer. I didn’t know this before! Neil I also like your anthropology answer…we are built to have a tribe!

Comments