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Jul 24
Why Do People Have Periods When Most Mammals Don’t?
About Periods Menstruation is a biological process that occurs primarily in humans, some primates, and a few other mammals, and it involves the shedding of the uterine lining (endometrium) when pregnancy does not occur. Most mammals, however, do not menstruate in the same way, raising the question of why this process exists in certain species […]