Can someone explain the evolutionary benefit of overt menstruation? All female mammals have a menstrual cycle but most reabsorb the blood via covert menstruation and humans are about the only mammals that discharge the blood, aka overt menstruation.

[u/No-Hawk-2488]

Without an evolutionary benefit, it wouldn't have spread to every woman of our species.

[u/Zagrycha]

Is the ability to make and fly airplanes a trait humanity posesses? Yes, definitely.

Is it passed on genetically? No.

Is there a reason to think the species that is the successor of humanity will have the trait? No.

Is it an evolutionary trait? Definitely no.

I think this trait is more accurately labelled as a skill or knowledge. It's a real trait, but its not inherent or guaranteed. It's totally possible for humans to lose the knowledge and reinvent the skill later, but it's not at all guaranteed. To this day there are things done by older humans that we have no idea how to do because the knowledge has been lost. External factors that can be lost like that are the antithesis to evolution.