Evolution and the Human Tail

THE birth of a child with a caudal appendage resembling a tail generates an unusual amount of interest, excitement, and anxiety. There is something seemingly unhuman about the presence on a human infant of a "tail" like the tails found on other primates. It is incongruous; it violates our sense of anthropocentricity, and it raises issues that involve not only teratology and embryology but also our view of ourselves and our place in evolution.The human tail has long been an object of scientific curiosity.1 2 3 During the early part of the 19th century the caudal appendage was considered to be . . .