A Wonderleaf question
Why do we yawn?
a real page from the book
We yawn because the body seems to help the brain keep a workable temperature, especially when we are sleepy, bored, or newly awake. A wide breath shifts cooler air past blood vessels near the head; studies have not found a real oxygen top-up.
The lovely oddity is that yawns spread socially. Seeing one can set off your own, likely through mirror neurons, brain cells involved in copying and understanding others. Dogs, chimps, and some birds can catch yawns too, as if bodies quietly compare notes.
Wonder words
- oxygen
- neurons
- empathy
- temperature
Try it out
At bedtime, take turns fake-yawning and notice whether a real one sneaks in before lights out.
Read the whole picture book
Watercolour scenes, straight answers, about three minutes cover to cover.
Open the picture bookKeep wondering
- Why does hair grow?
- How do germs get inside the body?
- Why do we cry tears?
- Why do we sweat?
- Why does my stomach growl?
- Why do we have a belly button?
One more wonder: Why is space so dark?
And the next question?
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