Continuing my ongoing investigation into fertility, I wanted to take another look at who’s having children. This post will look at fertility from a different angle: the spread in fertility by sex, IQ, political orientation, and education.
I was prompted to this by a recent article describing parenthood in Norway. It found that a fifth to a quarter of men from the Boom generation and the generation following had no children.
This finding is highly similar to what I found previously for the U.S.
The Norwegian study found that for high-IQ couples, it was often the husband who wished to delay procreation:
“My wife wanted a child sooner, and I wanted to wait. Hence, we married first. Maybe we then would decide to have children. It was my wife being very eager to have children.”
“To this man marriage was a strategy in order to put children off till later. Among the interviewees belonging to the upper middle class the desire to wait was prominent, especially among men. Many had been in a relationship for 10-12 years and were still childless. Their reason for not having children was that ‘the timing hadn’t been right’. In some cases this involved years of negotiations, mostly because the man wanted to wait,” says Jensen.
When having children was discussed among couples, the topic was normally brought up by the woman. This was a common feature for both classes. According to Jensen, an explanation to the fact that women are more in a hurry than men is that women have a biological time limit for having children, whereas men can produce children for a longer period of time.
By contrast, for low-IQ men, the pattern was different:
“Many of the childless men belonging to the working class were single. Their reason for not having children was primarily that they had not yet met the right partner. And in cases where men from the upper middle class had waited and carefully timed when to become fathers, the fathers among the working class had not given the timing much thought in advance. Having children was a natural part of life, and it happened when it happened,” says the researcher.
All of which sounds about right, and eerily familiar:
The article also notes that a genuine desire for childlessness is uncommon, which would be in agreement with a previous finding of mine.
Overall, my investigations have shown that between 10-25% of people failed to leave descendants, depending on the era. It was around 20% for White Americans for most time periods over the previous century, become lower for a time during the Baby Boom:
And of course, we know of the distinct IQ, sex, and political skew here:
But now, let’s look at it another way: at the discrete frequency breakdowns:
This is the number of children had by non-Hispanic White men, age 45-60, broken down by WORDSUM score (verbal IQ) and stated political orientation, taken from the 2000-2012 General Social Survey (GSS) data.
And below is the same, from men age 35-44. I had to take my data from the 1995-2012 GSS to increase sample size:
Now, while sample sizes across the board are generally small, we see an interesting pattern. As the previous data breaking down fertility by IQ and by sex show, fertility is dysgenic for women and roughly neutral for men by IQ. However, here we see that there is finer pattern behind this when you break it down. What is actually happening is that fertility is highly dysgenic by IQ for liberal men (for whom indeed, the smartest category of such men here – roughly IQ 115+ – about 50% leave no descendants); is slightly dysgenic for moderate men; and is slightly eugenic for conservative men.
And now, for women. These are non-Hispanic White women, age 45-60, broken down by WORDSUM score and stated political orientation, taken from the 2000-2012 GSS data:
And White women, age 35-44, from the 1995-2012 GSS data:
We see a similar pattern as we do with men, but a distinct one. Fertility is dysgenic for liberal women, but not nearly to the degree it appears to be for liberal men. The smartest moderate women however do appear quite unfecund. But, I seem to have uncovered another interesting phenomenon, one which I’ll call the Michele Bachmann/Sarah Palin Effect.
While fertility for conservative White women appears to be slightly eugenic, it is not because the smartest women are having most of the children. Rather, it’s the ones with only somewhat above average intelligence – the Sarah Palins and Michele Bachmanns of the country – who are having the most children, with 10% having 4 or more. Since among conservative men, it is the smartest ones who are having most of the children, this suggests that these men are married to women who are quite a bit less intelligent than their husbands (albeit, still above average in intelligence).
Maybe there is some truth to the notion that Palin and Bachmann attained popularity because they represented an ideal for conservative men: the pretty, dumb (or at least, not terribly smart), subordinate housewife.
Now lets look at this by education. These are the number of children had by non-Hispanic White men, age 45-60, broken down by highest degree attained and stated political orientation, taken from the 2000-2012 GSS data:
And the same, but aged 35-44, also from the 2000-2012 data:
As we can see, for most men, education appears to be roughly neutral on fertility, with the possible exception of liberal men who seem to take a fitness hit at higher levels of education (however, that this shows up only with younger men indicates that educated men may simply be having their children later).
And women (non-Hispanic Whites, age 45-60, 2000-2012 GSS):
And women age 35-44 (2000-2012 GSS):
Interestingly, as we can see, education is primarily a fitness hit for liberal women. It negatively impacts fertility for moderate and conservative women to a much lesser extent. But IQ doesn’t appear to be a huge fitness hit for conservative women, with the exception of the smartest. It seems that conservative women with a modicum of intelligence eschew education and opt for marriage and family, consistent with previous findings by myself and others.
But one thing is clear, even for liberals, the fitness hit of education is far stronger than the hit from IQ. This means that while breeding for liberal Whites selects against IQ, it much more strongly selects against education inclination. For women in particular, the interest in and/or ability for educational attainment is being selected out. This illustrates the finding of Marcus Jokela (discussed by me here) that it is not only the personality trait openness to experience (the hallmark of liberal-minded people) that is being selected out, but conscientiousness as well, at least for women. Because selection on men for this trait is roughly neutral, this trait is also declining in the White population.
Now, for certain of my educated liberal friends (you know who you are), you can see where this is going, and it’s not good. How many more of these reminders do I need to make before you do us all a favor – yourself very much included – and have children? Sooner rather than later, please. Think about it like doing your part to save the environment – or voting for your favorite candidate in an election. Don’t wait for the next guy to do it; you need to take matters into your own hands. Indeed, about saving the environment, having children is the best thing you can do for the future of humanity.
As it has been said, the future belongs to those who show up. At this rate, those who show up will contain a higher fraction of individuals who aren’t exactly the best ones to have around for the best interests for mankind. Only you can do something about that…