Biology/animal menstrual cycles
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Question
What female animals have a menstrual cycle?
Dear Michelle,
While most mammals have an estrus cycle, only some primates have an overt menstrual cycle that is similar to that of our own (we're primates, after all), in which the endometrium of the uterus is shed and exits via the vagina.
Other species undergo a thickening of the endometrium during estrus, but they resorb the endometrium at the end of the cycle, and do not shed it menstrually. Some sources refer to this as "covert menstruation," but if you're being strict about the definition of menstruation being a bleeding out of endometrium, then it's just humans and chimpanzees, and possibly a few other primates.
Hope that helps.
Dana
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Answers by Expert:
Dana Krempels, Ph.D.
Expertise
I can answer biology-related questions in the areas of evolution, zoology, botany, genetics, and ecology. But I don't answer homework questions or provide ideas for your science fair projects. So students please do your learning the right way by reading your text assignments and studying!
Experience
At the University of Miami, I teach Evolution and Biodiversity, Botany, Zoology, Genetics, Ecology, and a variety of seminars (e.g., the Biology and Evolution of Human Gender Roles).
Education/Credentials
I have a B.S. in Biology and an A.B. in English from the University of Southern California (1980).
I earned my Ph.D. in Biology in the area of evolutionary biology/visual physiology from the University of Miami in 1989.
Past/Present Clients
I am currently an "expert" in both the "Rabbits" and "Wild Animals" categories.
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