Respuesta :
Answer:
Drought, flood, and temperature changes could certainly push people to move on.
Explanation:
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.
Answer:
The ice covering most of the northern part of North America melted.
Explanation:
The land bridge allowed humans to reach North America, but they couldn't move farther south until the ice started to melt.