Even the mention of a yawn can trigger it.
Perhaps we are almost always in a state of needing a yawn, but the trigger is seldom met, and seeing or hearing about it is enough to make our brain go "oh yeah I forgot about that".
Perhaps yawning is actually underdeveloped and an ideal human would yawn at regular intervals without any prompting.
Same goes for sneezing, actually that's even worse for driving, I literally don't see anything for a second at least. Sometimes can be blocked, sometimes not so much.
That's a simplification, but you get the idea.
That depends. It can still affect genetic fitness if it affects an individual's ability to confer benefits on their descendants. Of note: most of the most wealthy and influential people in our society are beyond their reproductive years (not technically true for men, but mostly true in practice).
Edit: why am I being downvoted for this?
No, it isn't. It can be socially impolite to yawn unexcused, when someone is talking to you, as it has come to be interpreted as boredom rather than tiredness or similar. But it isn't inherently impolite to, for instance, yawn when walking down the street, or in a setting where someone isn't talking to you.
Because you don’t know what detrimental means in this context and clearly don’t understand evolutionary timescales?
Strangely, dogs sneeze to show deference.
Is that the paper in question?
I’m looking forward to “yawn to unlock”.
Also, what’s the deal with that article image?
> Anecdotal evidence suggests that yawning helps increase a person's alertness.
> Paratroopers have been noted to yawn during the moments before they exit their aircraft.
Brilliant, I'll use that next time I yawn somewhere inappropriately.
Distinctly remember being outraged.
Makes more sense I suppose if yawning isn't just signalling sleepiness to do it even while asleep!
Or - a change in those fluids makes me yawn?
happens to me a lot when i am on shrooms too
