[rand_r]

The evolutionary history of how we developed an instinct to hyperventilate is an interesting question.

However, I have to put up a warning that hyperventilating doesn't actually increase oxygen levels. It's a dangerous practice because it surpasses the natural drive to breath by depleting CO2 in the blood to abnormally low levels.

Our breath drive depends on CO2 levels and can get fooled by hyperventilation into letting you black out from lack of oxygen. This section on Wikipedia explains the physics of the situation really well: https://en.wikipedia.org/wiki/Freediving_blackout#Shallow_wa...

[rusk]

> The evolutionary history of how we developed an instinct to hyperventilate

Presumably it's a fight or flight response. It's redundant and counterproductive of course in many modern stress situations but if you had to fight off a predator or catch that animal the extra jolt of vascular activity probably makes perfect sense.

[bichiliad]

That was a really interesting link. It sounds here like hyperventilation, in practice, is dangerous only if you might become oxygen-starved right after (like in diving). A lot of these breathing exercises, like the one in the video above, aren't necessarily dangerous for that reason.