NCBI ROFL: And the most racist study of the year award goes to…

By ncbi rofl | March 10, 2011 7:00 pm

Associations between climate and IQ in the United States of America.

“Relations between average temperature of each of the 48 contiguous states and estimates of state IQ were inspected. Additional state variables were controlled in the correlational analyses, namely gross state product, percent Hispanic, Black, and Asian in the state population, and the pupil-to-teacher ratio for each state. A significant correlation between average temperature and state IQ was found (r = -.70, p < .001). Possible explanations are discussed.”

Bonus excerpt from the text:
“Significant negative relationships were found between state IQ and both winter (r = −.73, p < .001) and summer (r = −.53, p < .001) temperatures. Moreover, a significant negative association was found between state IQs and year-round temperatures (r = −.70, p < .001). Thus, as environmental temperature decreases, the state IQ tended to increase, congruent with the hypothesis and the findings of Templer and Arikawa (2006). While expected, these results are difficult to explain. Previous research has attributed the relationship between climate and IQ to the evolutionary process. Lynn (1991) posited that early humans who migrated from tropical climates to colder ones, were forced to undertake challenging cognitive tasks which resulted in selection for larger brain size and increased intelligence, relative to individuals and groups who remained in the warmer climates.

The United States population is composed largely of immigrant groups representing a wide range of ethnicities and geographical origins, with only 1.5% indigenous peoples. Relations between state IQ and climatic data must reflect characteristics of the various ethnic groups prior to their arrival in North America. Currently there are few additional challenges related to living in colder states, so it is difficult to see why the correlation between temperature and IQ persists. Perhaps, individuals from colder climates in Europe and Asia tended to migrate to similar colder climates in the USA. Whatever the cause, studies that have examined the stratification variables of intelligence test standardization samples have reported regional differences that agree with the present findings. ”

Photo: flickr/phunkstarr

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  • Neil
  • Georg

    What about IQ of Aleutians, Eskimos and so on?

  • Justin willcott

    Does this mean Sarah Palin is smarter than most of us?!

  • Swartz

    Cold weather is more likely to kill you if you are not smart. You must be smart to find food and shelter in colder climates. (Most likely this is all residual from periods where that was more true.) If you live you pass on genes. Ergo…

  • Steve D

    What, precisely is racist about this? Seriously, stow the invective and snide remarks and explain, step by painful step, how this is racist. The authors don’t claim any particular racial or ethnic groups have higher or lower IQ. In my experience, most people don’t have a clue how proof works, so this may be a novel experience for you.

    Reply to Justin Willcott: Sarah Palin is dumb as a bag of hammers, but she shines compared to most of the folks who comment at Daily Kos, Huffington Post or Crooks and Liars.

  • Joseph Hertzlinger

    We can obviously raise the average IQ of humanity with nuclear winter.

  • AC

    As contradictory evidence, I present the Teabaggers (and Republicans, in general).

  • ShunkW

    If this were true then the southern states wouldn’t be dumb enough to keep electing wingnuts.

  • Andrew

    @ Steve D

    This “explanation” from the institute of correlation=causation is racist for the reason that it supports the idea that Smart People come from Northern climates like Europe while hotter climates like Africa create Dumb People. As a result, the earnings inequality between black and white populations can be “justified” as a difference in intellectual ability.

    Using the the US data might not seem to imply this explicitly, but its an implicit conclusion that if lower temperature directly creates higher intelligence then the European conquest of the world between 1560-1945 is completely legitimate because they are somehow “superior”. I disagree, because there are too many counter examples (wheres the hyper-intelligent Inuit?), IQ is a poor measure of intellectual ability (it’s weighted towards Middle class type answers etc), and the study blatantly ignores every intervening variable between environment and individuals (like society, culture, history, institutions, customs, etc).

  • JChen

    Interesting to contrast this with the oft-expressed complaint that Caucasians are getting slowly pushed out of universities by Asians.

    I’ve an alternative hypothesis: it’s an economic, not climatic, pressure. Warmer climes encourages low-skill agricultural industries – hard labor, like that so loved and glorified by Conservatives. Colder climes don’t encourage intelligence directly – that’s simply where the cheaper land to establish more complex industry happens to be. In effect, there is no genetic variable in this – it’s simply a matter of what attracts what.

    The study, in other words, is incomplete. It’s noted a correlation, but hasn’t even begun to scratch causation.

  • Bryan

    I noted the following fatal flaw:

    Study presume IQ is primarily determined by heritability.

    Studies of heritability of IQ range from 20% to 80% heritable. That leaves open the possibility of up to an 80% environmental effect.

  • Thomas

    Historically, a higher parasite load in warmer climate led to worse health and thus lower intelligence.

  • Kwame


    citation needed.

  • Pedro Pagan

    Ok, why has the most seemingly-obvious answer gone overlooked here? Bryan hit on it a bit – “That leaves open the possibility of up to an 80% environmental effect.” Warmer climates encourage play. Socializing. Going out. Partying. Hell, having sex. The colder the climate, the fewer the distractions. People are far less likely to sit in a class or read a book if it’s 80 degrees and sunny outside vs 33 degrees and partly cloudy (current NYC weather.)

    As for the racist bit, I can see how it sounds racist, but only if the link was genetic. Here’s the perfect argument against that: India is really freaking hot. Intelligence is more about cultural/environmental influence than genetics. And yes, I’m thankful for this whenever I meet my relatives.

    I recommend reading “The Dumbest Generation”. It’s relevant, even if it’s just slightly over the top.

  • Matt B.

    @6 Joseph Hertzlinger
    Nuclear winter isn’t cold. It’s just analogous to winter in that not much is alive and moving.

    @8 Shunk Wugga
    You have it backward. High temperature correlates to stupidity.

  • Eric B.

    Perhaps people just perform better on tests when they are colder? I know I’m more alert when in cold temperatures. I wonder if the temperature of the room where the IQ tests were conducted were standardized? Seems like a pointless study with little to prove causation.

  • retarded white supremacists

    I have Joined your Feed =)


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NCBI ROFL is the brainchild of two Molecular and Cell Biology graduate students at UC Berkeley and features real research articles from the PubMed database (which is housed by the National Center for Biotechnology information, aka NCBI) that they find amusing (ROFL is a commonly-used internet acronym for "rolling on the floor, laughing"). Follow us on twitter: @ncbirofl


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