Double-headed Beings and Other Monsters

Abstract

Now and then a calf with two heads and six legs will be exhibited at a county or state fair, usually among the sideshows. Monsters of many kinds are known to occur in all sorts of animals and in humans as well. Among laymen, such malformations tend to be regarded as grotesque curiosities or, where human birth defects are involved, as something frightening and tragic. For the scientist, however, such cases of abnormal development represent “experiments of nature”—he wants to learn what has “gone wrong”, hoping thereby to gain a better understanding of the fundamental processes underlying all of development, as well as knowledge of more direct applicability to the medical problems of congenital malformations.