13. Reproductive Economics, Intelligence, Civilization, and Welfare

One of the most striking findings in psychometrics and sociology generally is that ~all positive things are mutually correlated. Here, “positive” refers to traits and behaviors generally seen as prosocial and individually beneficial in post-agricultural society. But why is this the case?

As it turns out, civilized human development can be well-modeled by a single axis. In this post, I’ll explain why, and talk about the various correlates of this axis.

The key variable of interest is paternal investment. This refers to the amount of time, effort, and resources a father invests in his children. Why is this more relevant than maternal investment? Because mothers must invest in their children. By default, reproduction costs men almost nothing but costs women a great deal in terms of calories, vulnerability during pregnancy, and risk of death from childbirth. Women will always care about making sure their children are well-fed and well-protected. But men’s investment is much more variable. Any unit of time men invest in caring for their children could also be spent procuring more mates and having more children. For paternal investment to be selected for evolutionarily, it must produce a higher expected number of grandchildren than the alternative strategy of impregnating as many women as possible. What variables increase the value of paternal investment relative to male promiscuity? One is paternity certainty. Women always know that their children are their genetic offspring, but men don’t. Investing resources in another man’s child is an evolutionary disadvantage. Men who do this will have fewer offspring on average and so will become a decreasing proportion of the population over time. Strategies that emphasize paternity certainty select for youth, since younger women will have had fewer previous male partners on average. This in turn creates selective pressure for women to continue looking young as they age. This results in a phenomenon known as neoteny, where adults increasingly retain childlike features as they age, such as large eyes, large heads, and slender builds. We also expect to see paternal investment co-evolve with cultural norms favoring fidelity and monogamy.

Agriculture and civilization also increase the relative benefit of paternal investment. In hunter-gatherer societies, a man generally does not accumulate property that he can leave to his children. But in settled societies, inheritance can meaningfully increase the reproductive success of one’s children. Thus, behaviors that result in inheritances (such as a well-run farm) are selected for. Selection for paternity certainty (and therefore neoteny) has a bidirectional relationship with intelligence. Passing the head through the vaginal canal is generally the riskiest part of pregnancy, so having children with large heads increases the chance that the woman will require a lot of care during recovery, and so she will need to select for men likely to stick around and provide that care. Furthermore, since there is such a large cost to birthing large heads, this creates pressure for more of development to happen after birth, resulting in more defenseless children and longer, slower life histories. All of these things make paternal investment more important. In the reverse direction, having a large head is a component of neoteny (since children have larger heads relative to their bodies than adults do). So men attracted to neotenous women need to stick around for their children or those children will likely die. This axis of development also reduces sexual dimorphism - the average physical and mental differences between the two sexes. Sexual dimorphism is a result of the different reproductive economy for men (reproduction is low-cost) and women (reproduction is high-cost). When paternal investment is common, this difference is less sharp. So, for example, women need to carry less fat if they can expect a loyal male partner to bring them food while they are vulnerable, and men in such societies will favor fat women less and thin (young-looking) women more.

This end of the development spectrum is k-selected. This is a biological term referring to a reproductive strategy where organisms have relatively fewer offspring but work to ensure their survival. Elephants are k-selected. The opposite strategy is r-selected, where organisms have as many offspring as possible and worry less about how many of them survive and reproduce. Locusts are r-selected. R-selected males prefer mates that seem highly fertile. K-selected males prefer mates that seem young and intelligent. K-selection is advantageous under a civilized, agricultural environment. It is selected for by this environment and produces people who prefer and are adapted to this environment. Recent results from the Reich lab confirm strong selection for intelligence and conscientiousness, and strong selection against obesity in post-agricultural civilizations. R-selection is suited to low-trust, low-inheritance hunter-gatherer environments.

How does this relate to welfare? In most modern liberal societies, welfare is given out in proportion to need, with particular sensitivity to the needs of children and single mothers. When such a society contains a mix of k-selected and r-selected peoples, the predictable result is that r-selected men will abandon their children (as they would generally do anyway) but rather than the natural counterbalance to this occurring (namely, that the children die of neglect) they are subsidized by the taxpaying k-selected population. Ks generally only feel secure having children when they can provide them a high material standard of living, while Rs will have children regardless. Thus, over time, the population of Rs will increase, which increases the tax burden on Ks, which reduces the propensity of Ks to have children, which further skews the population balance towards Rs and worsens these problems. Put simply, welfare is an engine that produces selective pressures against the very traits that make welfare states possible in the first place. It is a form of autocannabilism of advanced societies. Because of our unwillingness to watch children starve to death, we are slowly destroying the human capital that has produced all the amazing economic progress we enjoy today. Because we cannot tolerate this pain in the short term, we are incurring a debt that will result in incalculable misery for our descendants when the whole thing falls apart. This is not moral. This is cowardly.