TIL yawning is observed in almost all vertebrate animals and is "contagious" across species. There is no consensus on why yawning occurs.

https://lemmy.world/post/3355076

TIL yawning is observed in almost all vertebrate animals and is "contagious" across species. There is no consensus on why yawning occurs. - Lemmy.world

it exists to make evident it’s time to end the meeting
Prior to the adult life of the individual, however, this is a harmful trait as it only serves to make their teacher angry at them for no good reason whatsoever.