I was just digitally flipping through a new book called “Crime Against Nature“, which describes various reproductive behaviors in the animal kingdom. It is written by an artist, Gwenn Seemel, not a scientist, so I cannot vouch for the scientific accuracy of the book as a whole. However, the illustrations are quite nice and the content is seemingly scandalous, which makes for an interesting read.
For example, did you know that male Dayak fruit bats can lactate to feed their young (True according to this article in Nature)?
However, the notion that female spotted hyenas have a “penis” is not entirely accurate. It turns out that high-ranking alpha female hyenas are very aggressive and provide their developing offspring with higher levels of androgen (male sex hormone) than lower-ranking females in late pregnancy. This androgen boost increases the offspring’s chance of survival as it makes them more aggressive at fighting for food and at mating earlier and more often than those receiving less androgen. The problem is that the high androgen levels damage the mother’s ovaries and cause her clitoris to enlarge (up to 7 inches), thereby resembling a penis. Since the opening of the vaginal canal is at the end of the clitoris, it makes birthing a 2-pound cub through a 2-inch canal dangerous and often fatal for first time mothers. (Source: Michigan State University press release).
To judge the book for yourself, click here.