More intelligent people are significantly more likely to exhibit social values and religious and political preferences that are novel to the human species in evolutionary history. Specifically, liberalism and atheism, and for men (but not women), preference for sexual exclusivity correlate with higher intelligence, a new study finds.
The study, published in the March 2010 issue of the peer-reviewed scientific journal Social Psychology Quarterly, advances a new theory to explain why people form particular preferences and values. The theory suggests that more intelligent people are more likely than less intelligent people to adopt evolutionarily novel preferences and values, but intelligence does not correlate with preferences and values that are old enough to have been shaped by evolution over millions of years."
"Evolutionarily novel" preferences and values are those that humans are not biologically designed to have and our ancestors probably did not possess. In contrast, those that our ancestors had for millions of years are "evolutionarily familiar."
"General intelligence, the ability to think and reason, endowed our ancestors with advantages in solving evolutionarily novel problems for which they did not have innate solutions," says Satoshi Kanazawa, an evolutionary psychologist at the London School of Economics and Political Science. "As a result, more intelligent people are more likely to recognize and understand such novel entities and situations than less intelligent people, and some of these entities and situations are preferences, values, and lifestyles."
An earlier study by Kanazawa found that more intelligent individuals were more nocturnal, waking up and staying up later than less intelligent individuals. Because our ancestors lacked artificial light, they tended to wake up shortly before dawn and go to sleep shortly after dusk. Being nocturnal is evolutionarily novel.
In the current study, Kanazawa argues that humans are evolutionarily designed to be conservative, caring mostly about their family and friends, and being liberal, caring about an indefinite number of genetically unrelated strangers they never meet or interact with, is evolutionarily novel. So more intelligent children may be more likely to grow up to be liberals.
Data from the National Longitudinal Study of Adolescent Health (Add Health) support Kanazawa's hypothesis. Young adults who subjectively identify themselves as "very liberal" have an average IQ of 106 during adolescence while those who identify themselves as "very conservative" have an average IQ of 95 during adolescence.
Similarly, religion is a byproduct of humans' tendency to perceive agency and intention as causes of events, to see "the hands of God" at work behind otherwise natural phenomena. "Humans are evolutionarily designed to be paranoid, and they believe in God because they are paranoid," says Kanazawa. This innate bias toward paranoia served humans well when self-preservation and protection of their families and clans depended on extreme vigilance to all potential dangers. "So, more intelligent children are more likely to grow up to go against their natural evolutionary tendency to believe in God, and they become atheists."
Young adults who identify themselves as "not at all religious" have an average IQ of 103 during adolescence, while those who identify themselves as "very religious" have an average IQ of 97 during adolescence.
In addition, humans have always been mildly polygynous in evolutionary history. Men in polygynous marriages were not expected to be sexually exclusive to one mate, whereas men in monogamous marriages were. In sharp contrast, whether they are in a monogamous or polygynous marriage, women were always expected to be sexually exclusive to one mate. So being sexually exclusive is evolutionarily novel for men, but not for women. And the theory predicts that more intelligent men are more likely to value sexual exclusivity than less intelligent men, but general intelligence makes no difference for women's value on sexual exclusivity. Kanazawa's analysis of Add Health data supports these sex-specific predictions as well.
One intriguing but theoretically predicted finding of the study is that more intelligent people are no more or no less likely to value such evolutionarily familiar entities as marriage, family, children, and friends.
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The article "Why Liberals and Atheists Are More Intelligent" will be published in the March 2010 issue of Social Psychology Quarterly.