It's strange how I keep getting downvoted. The anti-genetic argument is a common argument brought up. I class it with other creationist style points as a "no, but..." type point. other ones include "no, but race doesn't exist..." and "no, but intelligence is a social construct...". they are common in that they are all objectively false and they're a type of widening of the goal posts of the argument. Intelligence tests measure intelligence in the most direct way they can, by testing intelligence. there is no more direct test that aside from mapping the structure of the brain directly. As far as needing a better understanding of intelligence... I agree that we need a more clearly defined definition. We understand intelligence very well. definition vary, however...each and every one of those definitions has been tested and the results are the same: a gap. The problem lies in our blank slate-ist mentality as a society. Intelligence, and behavior as a matter of fact, are rooted in biology. And biology differs with different human groups. We can see the differences in height and weight and blood type and epicanthic folds and skin color and bone structure and any number of other objectively measurable traits... its only when it comes to the effects of the structure of the brain that people start feeling uncomfortable. differences exist, we need to stop sweeping that fact under the rug and accept it.