Why do we yawn?
Talk about it together
Who do you notice yawning with you at home?
What about...?
Ask your child's own question
Transcript
Have you ever opened your mouth wide and yawned? Why does that happen?
When you feel sleepy, a sleepy signal grows stronger in your body. A yawn is one way your body changes gears.
Your mouth opens wide, and you take in a big breath. Your face and jaw stretch as your body wakes up a little.
Seeing someone yawn can make you yawn too. Brains often copy what other people do, especially people nearby.
So that's why we yawn: our bodies may be changing gears when we are sleepy. Yawns can spread when we see someone else yawn!
For grown-ups: the science
We yawn when our bodies are changing gears, often when we feel sleepy, and yawns can spread.
Yawning is common during transitions in alertness, especially sleepiness and waking, and may help regulate arousal. Its exact purpose is still not fully known. Contagious yawning is linked to social observation and develops during early childhood; it is not simply caused by needing more oxygen.