Children who Run on all Fours: and other Animal-like Behaviors in the Human Child

Abstract

SOME thirty years ago, Dr. Hrdlička, travelling in Mexico with Carl Lumholtz, saw an Indian child, well advanced in his second year, who ran about on all fours with hands and feet flat on the ground, knees slightly bent, body not far from the horizontal, and the head nearly in a line with the body. He was much struck by this unusual quadrupoid type of locomotion, very different from the young child's usual creeping, and obviously suggestive of the walking of gorilla, chimpanzee, and orang utan, when these apes are on all fours and not trying to be bipedal. There is this difference, however, that these apes rest their fore weight on their knuckles, and that the orang rests its hind weight on the outer edge of its foot.