Early Prehistory.

More than forty thousand years ago the Paleo-Indians began migrating into North America across the great land bridge that connected the continent to Asia. How they taught their children the skills necessary for survival in the Ice Age environment is unknown. Based on studies of ancient stone tools, refuse sites, and skeletons, archaeologists have forwarded several suggestions about the kind of culture the earliest immigrants had. It is fairly certain, for example, that men and perhaps women hunted in large groups mammals such as mammoths and giant sloths. Extending such inferences to the care and rearing of children, however, is quite difficult.

Archaic America.

Over time changes in the climate of North America and improvements in Paleo-Indian hunting skills decimated the continent's large mammal population. In the absence of big-game animals, Paleo- Indian groups had to adapt to the various local...