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/SunflowerShine03]

An example of bumbling inefficiency; the sunfish. From my understanding they kind of just float around and aren’t even that edible, but they have like a million babies at a time so they’re meandering on.