[William Tell]

I think I have read claims that the measured cognitive ability of blacks in the U.S. has risen in the last half century and reduced the gap with whites by about 25%.

This calls into question whether or not cognitive ability of a large population is immutable.

[MtnClimber]

I think much of the African low IQ problem is attributed to tribal inbreeding and childhood malnutrition. Those issues should cease to exist in the USA.