What common between the northeast southeast region?

A similarity that the Northeast and Southeast region have in common is that they contain areas of the Appalachian Trail. Speaking of the Appalachian Trail, they both have mountains. They both have the same cultures. They have farmers and do farming, but they do it in a different way and grow different crops. They both get 3 hurricanes each year. Finally, they both suffered great losses from the Civil War. 
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Yes you are cute answer theories to explain the colonization of the new world the last great habitable landmass to be occupied by humans focus on the bering land bridge, or beringia, which emerge by siberia and alaska the last ice age.