Maybe, but if so the planetary spread does not cause political differences -- and the two might not even be correlated.
That's the conclusion reached by Maria Konnikova writing at the New Yorker about linkages between personality and politics: Politics and Personality: Most of What You Read is Malarkey.
For many political psychologists, it seems abundantly clear that traits and politics go together. There’s evidence that many aspects of personality develop quite early in life and have a genetic component, but we don’t become actively political until we are older. So it’s sensible to assume that the one might have some bearing on the other. But most of the work on the subject in the past decades has consisted merely of scientists conducting surveys and observing correlations. Few researchers have ever asked whether what they’re seeing actually implies causality or if the correlations are even meaningful. (The fact that correlation does not equal causation has been amply illustrated by a self-styled correlation debunker, Tyler Vigen; a recent visit to his eponymous Web site shows a 0.998 regional correlation between U.S. spending on science and technology and suicides by hanging, strangulation, and suffocation.) And so, almost a decade ago, Brad Verhulst, a behavioral geneticist now at Virginia Commonwealth University, asked himself just that: Is the personality-politics link truly causal? A relationship between personality and political leanings is “a completely reasonable thing to expect,” he told me when we spoke recently. He wanted to use his knowledge as a geneticist to explore the causal linkage that he was certain would be there.
The short of it is that the behavioral genetics research - studies with twins vs. siblings - showed no causal linkages between political affiliation and personality. In one of the studies, twins and siblings were tested and then retested 10 years later.
... They found that personality did shift over time—not by huge amounts, but perceptibly. People could become more or less extroverted, more agreeable or conscientious, or any number of things. Political attitudes were slightly more stable, among both the adolescents and the adults: people who were conservative tended to stay conservative. And, most important, changes in personality did not predict changes in politics. “We conclude that both personality traits and political attitudes are independently part of one’s psychological architecture,” the authors write.
So why do we persist in believing that there are correlations, even causal linkages, between personality and politics? Even when what we desperately want to believe is not so.
... At least in the U.S., the party you believe in plays a big role in how you conceive of yourself. It feels good to think that your party is smarter, and that the smarts are what drive people to your party. It also feels good to say that the other guys are psychos. “ ‘It’s spurious, there’s no causal relationship,’ ” Verhulst says. “That could be pretty depressing for people who’ve invested a lot of time in this.” Here’s what won’t make a good headline: “Small and Spurious Correlation Shown to Have Been Backward, but It Doesn’t Matter That Much, Because the Point of the Paper Was That There Is No Underlying Causation After All.”
Social psychology touches on our most cherished beliefs about how the world should operate. We are more than happy to accept the counterintuitive—as long as it doesn’t conflict with our central notions of what ought to be. And, when it comes to politics, it can be awfully difficult to put your desires aside and to acknowledge that the world is a much messier place, where open-minded people might be conservative and liberals may well be conscientious. “People get passionate when they’re talking about these things,” Verhulst points out. “It would be nice if it was less passionate, but political values really do have a profound impact on our daily lives, as do the personality traits we have. They are fundamentally striking at what it means to be human.” And so levelheadedness remains difficult. Here’s a headline you’re not so likely to see: “Conservatives Are from Earth, Liberals Are from Earth, and Scientists Aren’t Really Sure About How They End Up That Way.”