USA HISTORY

Detailed explanation-1: -Scientists one theorized that the ancestors of today’s Native Americans reached North America by walking across this land bridge and made their way southward by following passages in the ice as they searched for food. New evidence shows that some may have arrived by boat, following ancient coastlines.

Detailed explanation-2: -Earlier studies had indicated that people moved into the Americas at the end of the last ice age, traveling from Siberia to Alaska across a land bridge now under the Bering Sea. They spread southward, eventually reaching the tip of South America.

Detailed explanation-3: -Whereas archaeologists once thought that the earliest arrivals wandered into the continent through a gap in the ice age glaciers covering Canada, most researchers today think the first inhabitants came by sea.

Detailed explanation-4: -Drought, flood, and temperature changes could certainly push people to move on. Climate change also affects the food supply, and anthropologists have assumed that people came to the Americas because they were following food on the hoof.

Detailed explanation-5: -The traditional theory postulates human migration across the Bering Land Bridge and then southward through a deglaciation corridor in western Canada. However, current research supports a maritime route along the southern coast of the Bering Land Bridge and Gulf of Alaska, and then southward along the Northwest Coast.