People moved here looking for more land and room to grow.
People came here for opportunity and a chance to have a better life.
People came here across the land bridge trying to find a warmer climate.
People came here across the land bridge as nomads following the animals they hunted.
All of the above
Climate got colder and food was in short supply
Farming began after a long drought (no rain)
Advanced civilization began after farming allowed trade to happen
People were able to change their language because they no longer lived in the same place as before
Taking a boat across the Pacific Ocean from what is now Japan
Walking over a land bridge in what is now the Bering Strait
Swimming across a channel separating modern Russia and Alaska
Canoeing across the Atlantic Ocean from northern Africa
Here's an interesting quiz for you.