One chart reveals the most widely believed conspiracy theories in America

Americans believe in some seriously wacky conspiracy theories. Did you know, for example, that millions of Americans may believe our government is run by "lizard people"? Did you know that one third of the country thinks global warming is a lie? And 36% think Obama is hiding something about his past? And that apparently, the entire internet believes One Direction singer Louis Tomlinson's baby isn't real?

Conspiracy theories aren't inherently bad. Even the psychologists who study them say that a healthy dose of skepticism is a good thing.

"If we were all completely trusting, it would not be good for survival," psychologist Rob Brotherton told the Guardian. "Sometimes people really don't have our best interests in mind."

But there's a clear line between healthy skepticism and plain paranoia. Researchers still haven't figured out what causes someone step from logical thinking into the illogical thinking that underlies a conspiracy theory. It might have to do with people trying to regain a sense of control over their life, according to the Guardian. And people who are more suspicious and untrusting by nature may be more likely to subscribe to a conspiracy theory, like the whole reptilian-overlords thing.

But regardless of how it happens, psychologists say a fairly large number of people believe in at least some version of a conspiracy theory. According to the Guardian, you probably know at least one of them.

To calculate America's most popular conspiracy theories, we used data from a Public Policy Polling survey in 2013 (with 1,247 respondents), a poll from SSRS of Media in 2015 (with 1,018 respondents) and a Fairleigh Dickinson University poll in 2012 (with 814 respondents).

The comparison isn't perfect, but we were able to find the 10 conspiracies with the highest number of believers across the three polls.

Here are the findings:

• 51% think the JFK assassination was a conspiracy

• 44% think Bush lied about weapons of mass destruction in Iraq

• 37% think global warming is a hoax

• 36% think Obama lied about his background

• 29% think aliens exist

• 29% think the Central Intelligence Agency tested LSD on Americans

• 28% think the New World Order is real

• 25% think Bush knew 9/11 would happen

• 23% think Bush committed voter fraud 2004

• 21% think a UFO crashed in Minnesota in 1947

Seriously, America? The polls only represent a small sample size of Americans, that's still a surprising number of people. Over half of all respondents think the JFK assassination was part of a larger conspiracy.

See photos of JFK through the years:

Less widespread theories still have staggering numbers of believers.

• 14% of Americans believe Bigfoot is real

• 7% think the mood landing was fake

The most bizarre of all?

• 4% think the government is run by "lizard people."

Incredible. But hey, it's still less far-fetched than Ted Cruz being the Zodiac killer, right?

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