Humans are all one species but we are not all the same. We're not even evolving the same, if you look at it on a surface level. Americans are taller on average than a hundred years ago and the Dutch are probably the tallest people on the planet. We're guiding evolution, believe everyone except biologists. Why doesn't that extend to social issues? What if pretty people married only pretty people? What if liberals married only pretty people? Would not conservatives die off in evolution because they got uglier and less able to mate?  

'Consensus' is the ugly word political scientists have tried to invoke to try and inject some science into politics. They contend your political party isn't just free thought, rational evidence-based decision-making. 'Consensus' is, of course, a word with emotional verbage attached to it in modern American discourse. Consensus to the public means 'we took a vote' or 'we averaged out our numbers' whereas in science it means 'we have a confidence interval because we have crazy outliers, just like people in any business do'.

In 2009, they also said there was a party happening in your genes.

Even mating obeys the biology of political science. You can learn a lot about a person by learning about their mate,Hibbing and colleagues wrote in 2011.

So liberals, if you really want conservatives to disappear, marry one. The science is settled.

Lincoln, Neb., July 31, 2014 -- Do people make a rational choice to be liberal or conservative? Do their mothers raise them that way? Is it a matter of genetics?

Two political scientists from the University of Nebraska-Lincoln and a colleague from Rice University say that neither conscious decision-making nor parental upbringing fully explain why some people lean left while others lean right.

A growing body of evidence shows that physiological responses and deep-seated psychology are at the core of political differences, the researchers say in the latest issue of the journal Behavioral and Brain Sciences.

"Politics might not be in our souls, but it probably is in our DNA," says the article written by political scientists John Hibbing and Kevin Smith of UNL and John Alford of Rice University. Hibbing has been telling biologists what's what for a long time time. He conjectured that if you are alarmed by bumps in the night, you are more likely to want protection over individual privacy and freedom. In other words, you are a liberal defending the administration's policies on snooping into everyone's lives.

Except he wasn't saying that at all, he was taking a shot at Republicans and insisting they were motivated by fear in 2008. And that is the problem with finding a cultural topology and mapping science to it - it's easy, but a few years later the exact same result can mean the opposite, simply because circumstances change. That, and measuring skin responses of 46 people to declare a physiology of politics isn't valid. 

"These natural tendencies to perceive the physical world in different ways may in turn be responsible for striking moments of political and ideological conflict throughout history," Alford said.

Using eye-tracking equipment and skin conductance detectors, the three researchers have observed that conservatives tend to have more intense reactions to negative stimuli, such as photos of people eating worms, burning houses or maggot-infested wounds.

Combining their own results with similar findings from other researchers around the world, the team proposes that this so-called "negativity bias" may be a common factor that helps define the difference between conservatives, with their emphasis on stability and order, and liberals, with their emphasis on progress and innovation.

Pictured are University of Nebraska-Lincoln political scientists Kevin Smith, left, and John Hibbing, right.

(Photo Credit: University Communications, University of Nebraska-Lincoln/Craig Chandler)

"Across research methods, samples and countries, conservatives have been found to be quicker to focus on the negative, to spend longer looking at the negative, and to be more distracted by the negative," the researchers wrote.

The researchers caution that they make no value judgments about this finding. In fact, some studies show that conservatives, despite their quickness to detect threats, are happier overall than liberals. And all people, whether liberal, conservative or somewhere in between, tend to be more alert to the negative than to the positive -- for good evolutionary reasons. The harm caused by negative events, such as infection, injury and death, often outweighs the benefits brought by positive events.

"We see the 'negativity bias' as a common finding that emerges from a large body of empirical studies done not just by us, but by many other research teams around the world," Smith explained. "We make the case in this article that negativity bias clearly and consistently separates liberals from conservatives."

The most notable feature about the negativity bias is not that it exists, but that it varies so much from person to person, the researchers said.

"Conservatives are fond of saying 'liberals just don't get it,' and liberals are convinced that conservatives magnify threats," Hibbing said. "Systematic evidence suggests both are correct."

Many scientists appear to agree with the findings by Hibbing, Smith and Alford. More than 50 scientists contributed 26 peer commentary articles discussing the Behavioral and Brain Sciences article.

Only three or four of the articles seriously disputed the negativity bias hypothesis. The remainder accepted the general concept, while suggesting modifications such as better defining and conceptualizing a negativity bias; more deeply exploring its nature and origins; and more clearly defining liberalism and conservatism across history and culture.