Menstruation (mammal)
Menstruation in mammals is the shedding of the uterine lining (endometrium). It occurs on a regular basis in uninseminated sexually reproductive-age females of certain mammal species.
Menopause
Menopause has been observed in several species of nonhuman primates, including rhesus monkeys and chimpanzees. Menopause also has been reported in a variety of other vertebrate species including elephants, short-finned pilot whales, killer whales, narwhals, beluga whales, the guppy, the platyfish, the budgerigar, the laboratory rat and mouse, and the opossum. However, with the exception of the short-finned pilot whale, killer whale, narwhals, and beluga whales, such examples tend to be from captive individuals, and thus they are not necessarily representative of what happens in natural populations in the wild.