From time immemorial it has been known that there is something peculiar about the sexual anatomy and physiology of the spotted hyaena. The writers of antiquity relate the legend that this animal is hermaphrodite, or that it can change its sex at will. Aristotle (384-322 B.C.) mentions the story, but says that it is untrue. He did not, however, distinguish between the spotted and striped hyaenas: the legend relates to the spotted hyaena, but his refutation to the striped, the genital anatomy of which he correctly describes. Pliny the Elder (A.D. 23-79) repeats the legend, mentioning Aristotle’s denial of its truth. Claudius Aelianus ( ca. A.D. 160-220) also states th at the hyaena changes its sex in alternate years.