Intelligence: How much is heredity and how much environment?

Double helix DNA pioneer James Watson had to resign his job recently over remarks about race and intelligence. Recently, I learned about a finding on intelligence that might prompt people to rethink their approach to it - the Flynn effect. As Richard Restak explains it in American Scholar,

Flynn’s most intriguing and controversial claim concerns the preponderant influence of the environment over genetic inheritance in determining intelligence. The direct effect of genes on IQ accounts for only 36 percent of IQ variance, Flynn tells us, with 64 percent resulting from the indirect effect of genes plus environmental differences uncorrelated with genes. Yet this cheeky claim would seem to be contradicted by the fact that identical twins separated at birth and raised apart end up with very similar IQs, presumably because of their identical genes. Not so, says Flynn, who buttresses his argument by drawing on an analogy from basketball.

If on the basis of their genetic inheritance, separated-twin pairs are tall, quick, and athletically inclined, both members are likely to be interested in basketball, practice assiduously, play better, and eventually attract the attention of basketball coaches capable of transforming them into world-class competitors. Other twin pairs, in contrast, endowed with shared genes that predispose them to be shorter and stodgier than average will display little aptitude or enthusiasm for playing basketball and will end up as spectators rather than as players.

Well, that’s basketball. What about IQ?

“Genetic advantages that may have been quite modest at birth have a huge effect on eventual basketball skills by getting matched with better environments,” Flynn writes. He suggests a similar environmental influence on genetic inheritance in regard to IQ: Twins with even a slight genetic IQ advantage are more likely to be drawn toward learning, perform better during their primary and secondary education, and thereby gain acceptance into top-tier universities. In the process, their IQ levels are likely to increase even further.

According to Flynn, the environment will always be the principal determinant of whether or not a particular genetic predisposition gets to be fully expressed. “There is a strong tendency for a genetic advantage or disadvantage to get more and more matched to a corresponding environment,” he writes.

In other words, the focus on genetic inheritance is misplaced if it encourages people to look for smart genes, at the expense of looking for environments in which they may be expressed.

While we’re here, one thing has always bugged me about the stories of “identical twins raised apart” who turned out to be similar: While they do provide strong evidence for genetic inheritance of some characteristics, it may not be as strong as some think. When social workers must find homes for identical twins, they don’t send one to live with a drug dealer down on the waterfront and the other to live with a mad prophet up on a lonely mountain. They place children with conventional people who can’t have kids. So the people who get to adopt babies are not a random sample of humanity. They are people whom social workers expect to be responsible parents. They are also people willing to undergo the hassle of home studies and the endless waits for a baby (and also unwilling or unable to just raise $50,000 cash and hit the black or grey market).

I am not knocking identical twin studies. I just think that we shouldn’t discount the “who do social workers think would make a good parent?” effect in determining outcomes. And remember, it was usually the same social workers making the decision for both of the twins ...

US anti-religious group loses standing to fight lawsuits

In a move that might well signal a move toward reasonable accommodation of religious practice in public spaces, the American Civil Liberties Union was refused standing in two recent decisions.

The legal concept of “standing” discourages nuisance lawsuits by requiring that the plaintiff (person who is suing) has suffered actual harm. For example, if my neighbour builds a shrine in his back yard and prays there, I do not suffer actual harm in the eyes of the law simply because I think the shrine is ugly, and anyway I belong to a different religion that just doesn’t “do” back yard shrines.

However, the ACLU had - for years - got courts to agree to waive the requirement of showing actual harm. But now, courts are digging in their heels.

Columnist Jared Lorence explains:

Two federal appellate courts said “enough” and have recently thrown out ACLU lawsuits brought to stop prayer before the Indiana Legislature and a school board in Louisiana because the ACLU’s clients had suffered no harm—that is, they “lacked standing” to bring a lawsuit in the first place. So, rulings on “standing” are now protecting public prayer.

He adds,

The ACLU and its allies have been getting away with this for decades. Representing clients that have experienced no real harm, they have succeeded in eliminating ceremonies and other practices mentioning God and our nation’s dependence on Him, some of which date back to before the founding of our Republic. But finally the courts are waking up. They are imposing the standing rules across the board and rejecting these lawsuits until the ACLU finds someone who has actually been harmed by the government’s actions.

“Harmed”, notice, not merely “offended”. Let alone convinced that the world would be a better place if everyone had to do whatever they told us.

Religious freedom: Canadian Broadcasting Corporation lifts ban on persecution documentary

The documentary Beyond the Red Wall, that the Canadian Broadcasting Corporation tried to scuttle - because the Chinese government disapproved of its revelations about the persecution of Falun Gong in China - did apparently run.

Books at home predict student success better than parents’ education

This article by Motoko Rich in the New York Times reveals a striking fact that seems intuitively right:

In examining the average 2005 math scores of 12th graders who lived in homes with fewer than 10 books, an analysis of federal Education Department statistics found that those students scored much lower than those who lived in homes with more than 100 books. Although some of those results could be attributed to income gaps, Mr. Iyengar noted that students who lived in homes with more than 100 books but whose parents only completed high school scored higher on math tests than those students whose parents held college degrees (and were therefore likely to earn higher incomes) but who lived in homes with fewer than 10 books.

Why might lots of books predict educational success better than parent degrees? Well, homes with 100 or more books are homes where people think that reading is a normal way to learn. If I were asked to make a case for books, I would NOT say that people “ought” to read books (rather than watch TV or surf the net or trade creative profanities with passers-by).

Speaking as a non-fiction writer, I would say rather that reading is a more EFFICIENT way to learn and intelligently experience life – in other words, a better use of one’s time.

Once people have got used to learning from books, I find that they tend to prefer it. The reason is that concentrating on a still page is actually more efficient than watching a flickering procession of images troll past. It takes time to get used to reading, but once you have, you don’t go back to methods where you have less control and less ability to concentrate.

So why do I blog? Because it takes years to get a book into production. The Spiritual Brain was started in July 2005 and didn’t see print until September 2007. A lot of work went into that book, and the person who reads it will have a very clear grasp of the case for non-materialist neuroscience (and against materialist neuroscience). But it’s not the very latest news. Thus, I have found, blogging and writing books go very well together. I write a book every couple of years, and blog continually in the meantime.

Faking out brain injury tests, with a little help from friends

When I first saw this headline, “Brain Injury Tests Changed Because Troops Caught Cheating,” on a November 19 story by Catherine Donaldson-Evans for Fox News, I assumed that troops were faking a brain injury to get out of a danger zone.

Not at all. They were pretending that they did not have a brain injury, in order to rejoin their comrades. One way they did it was by learning the answers to standard questions from other soldiers who had been through the routine. So now the questions have been changed. Apparently, football players have also been known to try to fake out brain injury tests in order to return to the game as soon as possible.

The problem that concerns the army medics is that people with brain injuries may not make good decisions, and they could put others at risk as well as themselves.

Troop leaders know that injured soldiers who beat the diagnostic exam may make costly mistakes when they return to battle, but many of the soldiers and Marines who cheat may not be fully cognizant of the possible consequences — and if they are, they may be willing to take that chance.

The injuries were, of course, minor; if open, bleeding wounds were noticed, the soldier would not be sent back even if all the questions were answered correctly.

I can remember when, decades ago, brain injuries were considered a neural and mental death sentence. But in the 1990s, neuroscientists began to address the remarkable plasticity of the brain. And the key to that plasticity is - as in this story - the plasticity of the mind. Presumably, the army medics had not realized that soldiers would simply teach their buddies how to fake out the test and get back to the unit ASAP.

Service note

Toronto-based Canadian journalist Denyse O'Leary (www.designorchance.com) is the author of the multiple award-winning By Design or by Chance? (Augsburg Fortress 2004), anoverview of the intelligent design controversy, and of Faith@Science. She was named CBA Canada's Recommended Author of the Year in 2005 and is co-author, with Montreal neuroscientist Mario Beauregard, of the The Spiritual Brain: A neuroscientist's case for the existence of the soul (Harper 2007).

My other blog is the Post-Darwinist, detailing events of interest in the intelligent design controversy.