It may be genetics.

Researchers have claimed that our urge to explore the world is at least partially rooted in a genetic mutation known as DRD4-7R, aka the explorer's or adventurer's gene. In 1999, an extensive study by the University of California found this genetic mutation more common in nomadic, migratory populations. A follow-up study looked at 18 indigenous populations living along the ancient African migratory routes, and found that the DRD4-7R gene, along with its cousin 2R, is indeed more common in the people who have traveled the farthest from their ancestral homes.

NASA
Some farther than others.

And you might have it too! The explorer's gene is thought to be in 20 percent of the population, and it's probably the reason you're shifting in your chair right now, yearning to explore strange new frontiers and bone exotic green women.

Denmark consistently ranks as the world's happiest nation. Why is that? After accounting for known causes of public euphoria, like spiked water supplies and marijuana infernos, researchers from the University of Warwick finally isolated a genetic mutation in the Danish population which grants them an almost superhuman proclivity for joy.

kaorinne/iStock/Getty Images
All the pastry probably doesn't hurt anybody's mood, either.

This gene exists in both "short" and "long" versions, with the long version causing happiness by regulating increased re-uptake of the "feel-good" chemical serotonin, and the shorter version causing neuroses and vague dissatisfaction. The Dutch and the Danes are the least likely populations to harbor short-gened individuals (yet strangely, amongst the most likely to wear jean shorts).

Halfpoint/iStock/Getty Images
Apparently, the trade-off for all that happiness is a nation where everybody looks like your dad at a barbecue.

It's not tied solely to location -- Danish-derived populations born elsewhere still retain their giddy genetics -- but it also works inversely. Since Denmark is the genetic epicenter of world happiness, that means that the farther a country is from Denmark's genetic composition, the more likely it is to be a miserable place. So fuck you yet again, Papua New Guinea.

So it was that the people of San Antonio de los Cobres set about evolving humanity's first known adaptation to a toxic chemical. With at least 7,000 years of practice under their belt, they're now so accustomed to their bullshit poisoned H2O that they can withstand its arsenic concentration -- which is a ridiculous 20 times more than what WHO deems safe for human consumption.

chameleonseye/iStock/Getty Images
"Choke on it, biochemistry."

Normally, metallic arsenic accumulates in the body, causing all sorts of problems, including the three Cs (convulsions, coma, and cancers). But the residents of los Cobres have developed a genetic mutation that gives their livers the ability to detoxify arsenic much more efficiently than regular people and expel it right out of their bodies. And that's their much cooler second superpower: the ability to pee straight poison.

The human body has two types of sweat glands. Eccrine glands are found all over the body and produce the sweat you're probably thinking of -- watery, salty, and relatively odorless. Apocrine glands excrete a thicker fluid, and the odor-producing bacteria it attracts is responsible for that funky smell you're starting to get real self-conscious about as you read this sentence.

Todd Warnock/DigitalVision/Getty Images
You may convince yourself that it's all in your head, but the buffer zone of empty cubicles is entirely too real.

That is, unless you're ethnically Asian.

East Asian and Korean populations have a millennia-old mutation that renders them relatively odorless. Their bodies are dotted with fewer apocrine glands, and they benefit from a genetic variant which regulates the composition of sweat. As result, their underarm secretions lack the tasty proteins and lipids that bacteria love to munch on, which goes a long way toward deleting their body odor.

Which is helpful, since there's not exactly an abundance of personal buffer space in East Asia.

The gene variant responsible for the apocrine gland drought is called ABCC11, and although there's a chance that the odd non-Asian person could have it, it's basically the genetic lottery. Only 2 percent of Europeans are estimated to have the "get out of body odor jail for free" gene. There's a flip side, though: If a population produces less body odor, it also tends to be more sensitive to said odor. Which is why everybody looks at you weird whenever you visit Seoul, you friggin' ogre.

Researchers used to think that the omega-3 fatty acids heavily present in their diet gifted the Inuit an uncommon resistance to cardiac disease and diabetes -- a "fact" that fish oil purveyors have exploited to the tune of billions of dollars. To figure out the real reason Inuit hearts don't just explode by the time they're 20, a Berkeley-led study analyzed the genetic differences between 191 Inuit Greenlanders, 60 Europeans, and 44 Han Chinese. Almost all of the Greenlanders (as opposed to just 2 percent of the Europeans and 15 percent of the Chinese) turned out to exhibit a genetic mutation that limits the body's own production of omega fats. This in itself might seem like a bad thing, because omega fats are good for you. But by lowering their production, the body also lowers the production of bad, heart-disease-causing LDL cholesterol, because those processes are related.

photonaj/iStock/Getty Images
Translation: Dust off the deep fryer.

It's not all rainbows and poutine, though. The genes that control fatty acid profiles are also implicated in height, so for their increased resistance to disease, the Inuit are an average 0.8 inches shorter than the average person. That's okay; we'd happily trade our prospective basketball career for an invulnerability to cheeseburgers.

Humanity's Sir-Mix-A-Lot-approved buttocks came about so we could better keep our torso upright. We developed relatively narrow waists and swinging arm motions to counter-balance our wildly flailing legs. We even borrowed a page from the kangaroo playbook with springy Achilles tendons which store and release mass amounts of energy. Last but not least, we lost our thick coats of hair to better allow body-wide sweating -- try running a marathon in a Bigfoot costume and you'll see why.

Internets_dalry/flickr
Which it turns out is an annual event in Austin, because of fucking course it's in Austin.

And that's just our engine and bodywork. The brain provides the nitro with a number of chemical cheat codes that can make us actually want to run. When our leptin (the hormone that makes you feel full) levels get low, they turbocharge the body, inducing an urge to find food and go as far as you have to in order to do it. And then there's the famous "runner's high," which, shockingly, isn't bullshit. Running was such an important facet to our evolution that our brain rewards runners by releasing natural narcotics known as endocannabinoids.

So go on: Get fucked up on jogging.

For more ways we're all a bunch of X-Men, check out 5 Superpowers We All Had As Babies (According To Science) and 5 Real Athletes With Strange-Ass Superpowers.

Subscribe to our YouTube channel, and check out Why Invisibility Is The Worst Superpower, and other videos you won't see on the site!

Also, follow us on Facebook, and let's go fight big mean people together.