[From teratology to mythology: ancient legends].

The mythology of the Greeks and Romans is full of monsters of fiction: giants, cyclops, centaurs, hydras, Gorgons… The accounts of travelers, reproduced in the Natural History of Pline l'Ancien reported the existence, in distant countries, of men with a dog's head (baboons), of men with a single tall foot (sciapode), beings whose face is embedded in the chest (or acephala blemmyes), to which must be added a wide variety of men with no mouth, no nose, or equipped with giant ears or feet turned backwards, as well as hermaphrodites. Teratology reports on monstrous births, which have constituted the factual basis from which the imagination conceived adults whose morphology corresponds to the monsters of legend. Newborns sirenomelia were behind the legend of sciapode and sirens. Cyclopia have inspired the legend of the cyclops. Anencephaly probably explains the description of headless or blemmyes. The genesis of the legend of baboons may have multiple origins: firstly the existence of people suffering from congenital hypertrichosis, on the other hand, the influence of Egyptian mythology where the god Anubis has a dog's head. The acardiac fetus may explain some monstrous forms, features the work of Hieronymus Bosch. The significance of the monsters of legend, their genesis, their persistence through the ages is complex. By approaching teratology, we added a new field of exploration of real monsters of antiquity and Middle Ages.