The clocks changed this weekend and now Queensland and Canberra are on the same time zone. This means I was talking to Danny at 7.40 am, not 8.40 am (yes, we talk live to air). I’m not really a morning person at the best of times but I was particularly sleepy as Eldest had come into me at 1 am after having nightmares and I didn’t get much sleep.
So I was yawning. A lot.
Therefore it seemed appropriate that we were talking about vertebrates with larger brains and more neurons tending to have longer-lasting yawns.
A large-scale animal study collected data on 1,291 separate yawns from zoo trips and online videos, across a total of 55 mammal and 46 bird species, and found “robust positive correlations” between how long an animal yawns for and the size of its brain.
The researchers don’t make any link to intelligence, only the size of the brain and the number of neurons it packs in; nor is there any reference to the frequency of yawning.
It’s not clear why we yawn at all, and some species don’t (such as giraffes) but there is a theory that we yawn to cool our brains. It would therefore follow that bigger brains need longer yawns to properly cool them.
This data shows that mammals yawn longer than birds. Birds have a higher core temperature than mammals, which means a greater temperature difference with the surrounding air, which means a shorter yawn is enough to pull in cooler air.
I love a yawning baby, and the photo attached to this post is of my Eldest just after he was born. He’ll never know…