This is actually something Art posted on Facebook. I don't know why he didn't post it here, but I don't mind doing it. I think it is really interesting.

http://tinyurl.com/cdvnhar
Will Humans Eventually All Look Like Brazilians?

Other recessive traits will drop to low levels too, according to University of Delaware evolutionary biologist John McDonald. "Because most immigrants to the U.S. are from Asia, Africa or Latin America, any trait that is more common in northern Europeans than in the rest of the world will get less common over the near future in the U.S. due to immigration," McDonald wrote in an email. "Examples would include red and blond hair, blue eyes, and freckles. Traits that are recessive and are more common in some groups than others will decrease due to blending; blue eyes, sickle cell anemia, and cystic fibrosis are examples of this."

A population forged from the long-term mixing of Africans, Native Americans and Europeans serves as an archetype for the future of humanity, Stearns said: A few centuries from now, we're all going to look like Brazilians."