Voting: Nature or nurture?

When it comes to where people acquire their political beliefs, political scientists have analyzed many possibilities that might factor in, such as household income, gender and church attendance. It has long been thought that a person’s political ideals are something that comes mostly from their parents, friends or other environmental factors. However, there have emerged an increasing number of studies that suggest genetics may have an underlying role in both voter turnout and the way people vote.

Biology is something political scientists don’t generally acknowledge because it would seem the complex nature of politics is of too recent an origin to have a basis in genetics. But political scientist James Fowler of the University of California, San Diego became interested in the possibility that biology and genetics may indeed play a role when he noticed that people who vote do so consistently, despite the possibility their single vote won’t be a deciding factor in the election. Likewise, those who don’t vote are likely to be chronic non-voters.

What would you count as? Graphic by Steve Furtado.

Fowler started researching the matter by analyzing twin studies. Since identical twins share 100 percent of their DNA, while fraternal twins only share about 50 percent on average, identical twins should show more similarities in voting behavior than fraternal twins if genetics are a factor. His analysis of 326 identical twins and 196 fraternal twins showed that 60 percent of differences in voter turnout related to genetics while the other 40 percent were due to environmental factors.

By contrast, geneticist Robert Plomin of King’s College London analyzed the same data and concluded that only 40 percent of genetics were involved in voter differences in twins, though he says that is still significant. He goes on to say that many genes, not just a single gene, are likely a determining factor in whether people will vote or not, while environmental factors account for the rest.

Although Fowler suggested that genes only play a role in voter turnout, a geneticist named Nicholas Martin suggested that genetics can also play a role in people’s political beliefs according to Nature, the international weekly journal of science. Martin, who now works at Queensland Institute of Medical Research in Brisbane, Australia published, a study analyzing twin data.

His research concluded that identical twins share more political beliefs than fraternal twins. Twins usually grow up in very similar environments, so the differences in their attitudes are likely due to genetics.

However, there can be problems with twin studies. Researchers cannot weed out all environmental factors. Identical twins are more likely to have the same friends and stay in contact when they get older, compared to fraternal twins, for example. Behavioral neuroscientist Evan Balaban of McGill University warns against using twin studies because twins can also share the same bloodstream as fetuses, thus having similar levels of hormones and other biological factors that are not genetic.

An easier way to compare genes to politics would be to analyze how personality affects political beliefs. According to Nature, many political psychologists agree that the basic personality trait that governs people’s political ideas is willingness to change. They state that liberals are more often open to change and more willing to accept policies that lead to social change — such as legalizing gay marriage — while conservatives often are more likely to accept policies that keep the status quo, such as strict immigration laws.

However,  Evan Charney, a political scientist at Duke University in Durham, North Carolina, drew attention to the fact that this is not always the case. Some conservatives propose change, such as changes to the welfare system. He also states that he and most people in his field are liberal which could bias the way they interpret the results of their studies.

John Hibbing, a political scientist at the University of Nebraska–Lincoln, concludes that most importantly, these studies show that people are not as rational in acquiring their political beliefs as they may like to think. Genetics and environmental factors cause people to perceive the world in a certain way, and these perceptions necessarily affect how people behave. With this knowledge, he hopes people will develop more respect for others with opposing beliefs and ideas.