Week 3: Americans on the move.....

http://www.nytimes.com/interactive/2009/03/10/us/20090310-immigration-explorer.html

This is an interactive map of the changing patterns/distributions of the American population.

What are the reasons for the changes? - why do people migrate and relocate?
Why are Americans so 'mobile'?
Are the reasons the same for each historical period?
Look at the different patterns of the ethnic groups - what generalisations can you make?
This is a map of great complexity; it's a challenge to find the simple patterns, but, the simple approach is.....
Where? And, why there?
Are "environmental factors" influential? What evidence is there?
Good wishes,
John