Comments on Intelligence and Intelligence testing
 What does I.Q. Measure? An IQ score is one measure of how well an individual did on a particular test (or set of tests) at one particular point in time.

 Note that there are different types of intelligences, e.g., Gardner's, and 'practical intelligence'

 Key question: What factors influence IQ?
Heredity?
Environment?
e.g., birth order, S.E.S.,
What about 'race'?
Why are there differences in the IQ scores of black and white Americans? (Note these are group effects only - huge variability for both groups.)

There are several possible reasons:
Test bias?
Genetics?
Environment?

Heredity is a factor within groups, accounting for perhaps 30-50% of variation (not the 80% argued by Jensen), but: there is no evidence that it accounts for differences between groups (e.g., blacks and whites).

Heritability is not inevitability (there is a very large reaction range)

Also flaws of 'reification' (believing that there really is something called an IQ) and 'ranking' (assuming this 'thing' can be quantified in such a way that individuals and/or groups can be ranked along the measure)
There are no conclusive data demonstrating that group differences in IQ are genetically related.

To learn more, I encourage reading of the APA release on intelligence. It can be found here.