How did Humans end up in the Americas.

         I think that the early humans passed threw the land bridge and went down the coast of South and North america. On some parts of North America they had to use rafts because of the ice pack blocking the way. The artifacts and objects found date to around 1300 years ago in North America and South America. My mind changed when I learned about the artifacts under the river in Canada and that pollen that was dated at about the time that the early people passed the land bridge and traveled by foot and sometimes boat.