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A Compensation for Cold Weather: Higher IQs

New research finds that within the U.S., those states with cooler temperatures tend to have populations with higher IQs.
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With the red state/blue state divide rapidly devolving into a cliché, it’s clearly time to find a new way to splice the nation into subsections. Try this adversarial alignment on for size:

Smart states/dumb states. Which is to say, cold states/warm states.

It turns out those benumbed residents of Maine, Montana and Minnesota have something to brag about. A paper recently published in the journal Psychological Reports concludes that of the 48 contiguous United States, those with cooler average temperatures tend to have populations with higher IQs.

A research team led by psychologist Joseph Ryan of the University of Central Missouri calculated the mean year-round temperature for each state and compared it with estimated IQs. Those scores were measured by a standardized test, the National Assessment of Educational Progress, which is administered to fourth-, eighth- and 12th-graders across the nation.

Ryan and his colleagues then controlled for certain variables that could skew the results, including gross state product (which measures economic productivity), the percentages of black, Hispanic and Asian residents, and the average pupil-to-teacher ratio in the state’s schools.

Even with such factors removed from the equation, “a significant negative association was found between state IQs and year-round temperatures,” they report. “Thus, as environmental temperature decreases, the state IQ tended to increase.”

“While expected,” they add, “these results are difficult to explain.”

Expected? In a sense, yes. The results mirror those of an internationally focused 2006 study, which examined the relationship between climate and IQ in more than 120 countries. Donald Templer of the California School of Professional Psychology reported nations with lower temperatures tend to have higher IQs.

Ryan’s research found that same formula applies within the U.S. But it also calls into question the conclusions that have been drawn from such earlier studies.

“Previous research has attributed the relationship between climate and IQ to the evolutionary process,” Ryan and his colleagues note. As the theory goes, the ancestors of Swedes and Norwegians who were clever and resourceful enough to survive in that harsh climate passed down those heightened mental abilities to their descendants.

But as Ryan notes, less than 2 percent of the U.S. population is composed of indigenous people, which makes it unlikely that greater intelligence is a matter of climate-induced adaptation. “Perhaps individuals from colder climates in Europe and Asia tended to migrate to similar colder climates in the USA,” they speculate.

Of course, plenty of people have also migrated from frigid climates to Florida and California. What’s more, any cognitive challenges posed by colder climates were largely eliminated many generations ago. “It is difficult to see why the correlation between IQ and temperature persists,” the researchers concede.

It’s worth noting that IQ is only one measure of intelligence, and its critics contend it measures little more than the ability to take tests. In another newly published paper, Eliza Byington and Will Felps suggest the link between IQ and academic and career success can be traced in part to institutional reasons.

“IQ-reflective tests are used in primary and secondary schools to sort students into groups, and by universities and employers to select between applicants,” they note in the journal Research in Organizational Behavior. “We argue that (these processes) allow individuals with high IQ scores to receive greater access to developmental resources, enabling them to acquire additional capabilities over time, and ultimately perform their jobs better.”

But even if the validity of the IQ test is questionable, the relationship between a state's scores and its average temperature remains an intriguing puzzle. Perhaps it’s time to set up an institute to look at it further. Sounds like a job for those bitterly cold brainiacs at North Dakota State University at Fargo.