"as the average level of education in the population drives technological progress. This in turn increases the incentive to invest in education" (...) "Eventually, the rate of technological progress gets high enough to induce the quantity-preferring genotypes to invest in education." Why?

"eurocommunism was a working-class phenomenon from what i recall" 
 
I imagine that you want to say with "eurocommunismo" is "West European communism", and not exactly the ideology that it was known as "eurocommunismo" (who was, basically, Gorbachov-15-years-before). There is some overlapp between the 2 concepts, but they are not the same: Portuguese and Greek CP never were "eurocommunists", but hard-line traditional communists, and they were and are parties with strong support in the working-class; also the French and Italian CP were strong working-class parties even before his conversion to eurocommunism (in reality, specially in the french case, can be argued that the adoption of eurocommunism was the begining of the transformation of the CP from working-class parties to parties of "progressive intelectuals")

If left is "1-5" and right is "6-10", a median of 5.6 it is almost geometrical center (the center will be 5.5 » 0.1 points of difference could be only the statistically error, or the "Vietnam factor")

"I would guess that the women who accept the idea of personality being at least partly dependent on genes are women who have had more than one child. That is the "a-ha!" moment for many of us, when we notice that our children all have such dramatically different personalities despite all living in the same environment." 
 
I doubt, because I suspect that most people see "dramatically different personalities between brothers" as an argument against genetic personality. 
 
The reasoning "dramatically different personalities between brothers, then personality is genetic" could be logically true (or maybee not...), but it is much counter-intuitive.

Remember that "african"-americans are, in reallity, a mix of african and european ascenstry.