The psychological aspect of modernity I find most intriguing (and biologically unexpected) is the strong inverse correlation between IQ and fertility which has emerged in modern societies.

For example: In Lubinski's US top 1 in 10000 IQ sample the completed fertility rate of the women is going to be extremely low (probably about 0.5 child per woman - but 2.1 children per woman is the US replacement level).

http://www.vanderbilt.edu/ Peabod...Science2006.pdf

What, if anything, does this modern chosen-sterility of the most intelligent women tell us about ancestral hunter gatherers?

Jared Diamond in his GGS has revealed similar observation. Demoncracy and Egalitarianism are value of hunter-gagheres. `Human right' is valued more by primitive society.

Current trend is interesting. Wonder how long it gonna last.

One thing that I find especially interesting about these studies is that they seem to suggest a Flynn Effect on personality traits, assuming the difference between primitive peoples and modern peoples is environmental and not genetic.

A flynn effect on personality would I think go in contrast to the work of McRrae, but agree with the work of some others like Twenge and Rogler.

Ecological opportunities allow different responses, which influence development. This highlights the clash between hunter gatherer populations and sedentary agricultural communities. In a traditional hunter gatherer society (picture New York City) the working adults carry a small quantity of food to their home each day for that day's consumption as they lack (or choose not to use) technology to transport larger amounts of food. Due to economical restraints the hunter gatherer family spaces childbirths, often employing infanticide to guarantee sufficient resources are available for (and to insure the success of) a smaller number of children. Agrarian (red state) communities can produce and store large quantities of food, making economies of scale available for family sized units. More children can be supported by this system, and its sedentary nature makes raising a large family practical while also guaranteeing the future work force.

I think this is the first time in history that a hunter gatherer community has forced its cultural will on an agricultural community with any real success.

Karl Max also made same conclusion about human history. In his view, human in primitive tribes are living as communism with equality. Then brutal hiearchy in slavery, feudalism and capitalism. At end, equality coming back as final communism.

Today progressive trend seems confirming Karl Max idea, but not exactly.

I have noticed in Sweden that the men dress more femininely and the women are less dolled up. In summer, both sexes more or less wear the same clothes. There seems to be a morphing of the sexes there, at least in the way the sexes choose to present themselves. There is more male preening and less female preening. The women don't appear to want to pursue the more extreme expressions of femininity that I see in the USA and Australia. The girls may still want a pony but they can generally do without the heavy make up and slatternly clothes.