Our nation’s children are in peril. Two-career couples and single moms have little spare time for parenting. And don’t we all know that nothing is more important for children’s development than parenting? When you put those pervasive assumptions together, the future of the next generation seems bleak.
Fortunately, this gloomy forecast is probably mistaken. Researchers have examined its underlying assumptions and found that they are misleading at best. As often happens in academe, though, different disciplines have scrutinized different assumptions. As a result, no one group of researchers seems to fully appreciate how wrong the popular picture is.
Sociologists focus on the theory that parents spend less time with their kids than they used to. What do we really know about how people spend the hours of their day? A great deal, actually. For decades sociologists have been using surveys known as “time diaries” to study time usage. The idea is simple: You ask a random sample of people to walk you through a typical day, minute by minute.
High-quality time-diary studies go back about 40 years, which makes it possible to fact-check popular perceptions about the evolution of parenting. One major finding is unsurprising: Fathers spend much more time with their children than they used to. In 1965, the average father did three hours per week of primary child care; by 2000, he did seven. The next big result, though, is amazing: Today’s average mother spends more time in primary child care, too! That is true despite the fact that fathers do a lot more, despite the fact that families have fewer children, and despite the fact that modern moms are far more likely to work outside the home.
During any given era, admittedly, working moms spend less time taking care of their children than stay-at-home moms. Over time, however, both working and stay-at-home moms have sharply increased their hours of primary child care. In 2000, stay-at-home moms did 60 percent more than working moms; but working moms in 2000 did about as much as stay-at-home moms did in 1975.
Sociologists who publicize the shocking rise in parental effort usually embrace it as good news. Changing Rhythms of American Family Life (Russell Sage Foundation, 2006), probably the best book on the topic, concludes that time diaries “paint a rather optimistic picture of family change. Families can undergo great change and still somehow protect that which seems most dear. Mothers are maintaining their high levels of investment in child rearing, fathers are increasing theirs.” Like most of us, these sociologists seem to take for granted what Judith Harris calls “the nurture assumption” — the premise that parental upbringing has a large effect on how kids turn out. But psychologists have found that, once again, popularity is a poor test of truth.
“Nature versus nurture” may seem like an irresolvable debate, but psychologists who specialize in behavioral genetics have made enormous progress during the last few dec-ades. The main problem they faced is that, in the typical family, parents and children share both a home and half their genes; nature and nurture seamlessly blend together. Behavioral geneticists’ response was to find special families where the seams of heredity and upbringing are visible.
There are two kinds of special families: those with twins and those with adoptees. If you want to disentangle the effects of nature and nurture, one approach is to compare identical twins, who share all of their genes, to fraternal twins, who share only half. Another approach is to compare adoptees to members of their adoptive families. If identical twins are more similar than fraternal twins, we have strong reason to believe that the cause is nature. If adoptees resemble members of the families they grew up with, we have strong reason to believe that the cause is nurture.
By using — and refining — these twin and adoption methods, behavioral geneticists have produced credible answers to the nature-nurture controversy. To put it simply, nature wins. Heredity alone can account for almost all shared traits among siblings. “Environment” broadly defined has to matter, because even genetically identical twins are never literally identical. But the specific effects of family environment (“nurture”) are small to nonexistent. As Steven Pinker, a professor of psychology at Harvard University, summarizes the evidence:
“First, adult siblings are equally similar whether they grew up together or apart. Second, adoptive siblings are no more similar than two people plucked off the street at random. And third, identical twins are no more similar than one would expect from the effects of their shared genes.”
The punch line is that, at least within the normal range of parenting styles, how you raise your children has little effect on how your children turn out. You can be strict or permissive, involved or distant, encouraging or critical, religious or secular. In the long run, your kids will resemble you in many ways; but they would have resembled you about as much if they had never met you.
Recent scholarship does highlight some exceptions. For example, while earlier researchers found that divorce runs in families for purely genetic reasons, some new studies find that both nature and nurture play a role. Another study finds that controlling for genes, run-of-the-mill spanking does no lasting harm, but harsh physical punishment can leave lasting psychological scars. But even if many exceptions accumulate, the fact remains that people tend to greatly overestimate the power of nurture.
If family environment has little effect, why does almost everyone think the opposite? Behavior geneticists have a plausible explanation for our confusion: Family environment has substantial effects on children. Casual observers are right to think that parents can change their kids; the catch is that the effect of family environment largely fades out by adulthood. For example, one prominent study found that when adoptees are 3 to 4 years old, their IQ has a .20 correlation with the IQ of their adopting parents; but by the time adoptees are 12 years old, that correlation falls to 0. The lesson: Children are not like lumps of clay that parents mold for life; they are more like pieces of flexible plastic that respond to pressure, but pop back to their original shape when that pressure is released.
Many of us worry that our nation will pay a heavy price in years to come because modern parents are shirking their responsibilities to the next generation. If you combine the results from time diaries and behavioral genetics, however, you get a different picture. It turns out that there is some really good news and some mildly bad news. The really good news is that we can stop worrying about the horrible fate of the next generation. The bad news is that parents today are making large “investments” in their children that are unlikely to pay off.
Now if parents enjoyed every minute of child care, there wouldn’t be any bad news. Parents’ huge time commitment would be successful consumption, not failed investment. If you study parents at the next children’s event you attend, though, you will probably notice a lot of tired, grouchy faces. Happiness researchers confirm that impression. According to a study by a team of scholars led by the Nobel Prize-winning psychologist Daniel Kahneman, mothers enjoy child care just a little more than housework, and a lot less than watching television. As an economist, I have to suspect that a major reason for parents’ lack of enthusiasm for their role is simply diminishing marginal utility: Average enjoyment of parenting is low because parents are overdoing it.
You might respond, “Yes, but at least parental attention makes the children happier.” It’s striking, then, that even kids don’t seem to want all this parental attention. One notable study by Ellen Galinsky of the Families and Work Institute found that while most parents believe their children want more face time, only a tiny minority of children actually do. In contrast, about a third of children wish their parents were less stressed and tired. What kids seem to want from their parents isn’t more time; it’s a better attitude.
Ironically, then, a bird’s-eye view of parenting research suggests that it would be good for the world if parents stopped trying so hard. Parents would be better off, because they would be doing less of something that — through excessive familiarity — has lost its charm. Children wouldn’t be worse off, because parental “investment” has little payoff anyway. In fact, if we take children at their word, they’d be better off. Kids know better than anyone that if mom and dad aren’t happy, nobody’s happy.
Bryan Caplan is an associate professor of economics at George Mason University and author of The Myth of the Rational Voter: Why Democracies Choose Bad Policies (Princeton University Press, 2007). His next book, Selfish Reasons to Have More Kids, is scheduled to be published by Basic Books in 2011.
http://chronicle.com Section: The Chronicle Review Volume 55, Issue 20, Page B5
