I can find nothing in the studies there I really disagree with. It would make perfect sense in evolution for different sects to develop different traits to best utilize their environments and, intelligence (as we have devised ways to rate it) would not be immune to that trend.

What it points out to me though is that ultimately testing of individuals is a flawed process because it only evaluates a small percentage of a person's overall makeup. No test can completely assess the actual worth and progress of total human abilities. The superb hunter/gatherer traits the author claims are more highly developed in the African tribes can actually be very valuable traits in our advanced societies event though a standardized test might not even identify their existence.

Ultimately humans, if they must be rated, must be done so individually and, if those results have to be compared against one another, they have to contain the full picture including not only intelligence but artistic talents, social skills, imagination, athletic prowess, adaptation, and much more. I can't imagine any one test that can accurately rate all of those things. It's why for years we allowed our teachers, who got to see the full human essence each day in each of their students, decide who had amassed the skills necessary to go on to the next grade. Now some politician somewhere is allowed to decide a person's worth. I don't see that as a step forward in human evolution.

Art