"There are black people in every continent who are all over the world," explained Professor Celeste Watkins-Hayes, an African American studies professor at Northwestern University.

To test their hypothesis, the scientists—who somehow were awarded a grant for their work—examined the MRI brain results of people looking at images of faces of black people and white people.

But in Manassas Park, Va. and Weld County, Colo., the mean-life expectancy for Black residents is 96—a national high among all Black citizens by county. Black people are living in their 80s in ...