Explainer: why do women go through menopause?

Menstruation is a reproductive quirk that humans share with only a few other mammals. But even stranger is the fact that women stop menstruating when they have a whole third of their lives left to live.

All animals have a finite reproductive life. But more often than not, their reproductive system winds down at roughly the same time as every other system in the body – the menopausal killer whale is a notable exception.