Picturing mad scientists injecting glowing chemicals into tomatoes even while mega-corporations fill their bank accounts, many health-conscious consumers will do anything to avoid GMOs. But what if we told you that genetically modified crops existed even 8,000 years ago - modified by the hand of nature in the exact same way that scientists alter crops today?

How the heck is that possible? It's one thing to make the argument that any domesticated crop - where its natural selection was guided and even accelerated by human influence  - is a GMO. This argument, which was made widely popular by "science guy" Neil deGrasse Tyson, asserts that even your dog and the organic apples found at your local farmer's market are technically GMOs - as they certainly wouldn't have evolved and developed into the organisms that they are now had it not been for humanity.

"There are no wild, seedless watermelons. There's no wild cows... You list all the fruit, and all the vegetables, and ask yourself, is there a wild counterpart to this? If there is, it's not as large, it's not as sweet, it's not as juicy, and it has way more seeds in it," Tyson explained to several fans at a signing back in 2014. "We have systematically genetically modified all the foods, the vegetables, and animals that we have eaten ever since we cultivated them. It's called artificial selection."

The argument has long been that what is done in a lab - often called genetic editing - is just another form of this artificial selection, in which scientists re-order genetic information naturally found in a crop to ensure it expresses the desired traits. Even the Simplot potato, the latest of nine lab-made crops approved by the US Food and Drug Administration (FDA), was genetically edited so that it boasts LESS potential carcinogens than natural potato varieties.

However, there has always been a second variety of GMO that even educated parties have voiced some concern about. These are transgenic GMOs that were crafted in a process called genetic insertion. Unlike simple editing, these crops actually boast genetic information that the original organism never had - foreign information inserted into a crop's DNA with the help of designer bacteria. (Scroll to read on...)

The very understandable worry has always been that these crops - boasting traits they never could have achieved through natural selection - could contaminate the natural world or even express unforeseen genetic consequences.

Now, however, experts have found evidence that even transgenic crops have occurred naturally, without the help of a lab or even simple human meddling.

That's at least according to a study recently published in the Proceedings of the National Academy of Sciences (PNAS), which details how Scientists at the International Potato Center in Lima, Peru, have found 'foreign' genes in 291 sweet potato varieties untouched by science.

An investigation into the origins of these genes determined that the 'mad scientists' in this case were naturally occurring soil bacteria, and these sweet potatoes were likely first modified at least 8,000 years ago - long before the roots were being boiled, baked, or fried.

How is that possible? It actually shouldn't come as much of a surprise. The same bacteria family that is widely used for lab-side genetic insertion, called Agrobacterium, also happens to be a ubiquitous soil bacterium found all over the globe. Constantly feuding amongst themselves, these bacterium use their own genetic information almost like biological warfare. They attempt to infect one another with bits of DNA in bids to disrupt a neighbor during frequent turf wars. And while this has made soil bacteria particularly resilient antimicrobial powerhouses, it also makes them huge influences on the plant life they surround. (Scroll to read on...)

On occasion, these little 'DNA infections' can become something more, finding a permanent home in an organism's genome. And that's it! Suddenly you have a plant boasting utterly foreign genetic information. It's exceptionally rare, however, for those new genes to have an actual impact on the expression of traits.

And yet, that's exactly what the Potato Center researchers suspect occurred with sweet potatoes, making them the edible plants they are today. You see, unlike your run-of-the-mill potato, sweet potatoes aren't tubers, they're just very swollen roots.

"We think the bacteria genes help the plant produce two hormones that change the root and make it something edible," study lead Jan Kreuze recently told NPR's blog Goats and Soda. "We need to prove that, but right now, we can't find any sweet potatoes without these genes."

The researcher explained that when our ancestors first started farming, they likely stumbled upon the swollen roots and, thinking that they would make a fine soup, started strictly cultivating sweet potatoes boasting the foreign genes.

The rest, as they say, is history.

Still, the greatest irony is that the sweet potato has long been hailed as a healthier alternative compared to your standard starch dish. And health-conscious GMO opponents are no doubt some of the largest consumers of these soft, orangy roots.

Now, the next time you're sharing a basket of sweet potato fries in your favorite organic kale-wrap sandwich house, you can tell your friends that they're gnashing down on a serious GMO. Be sure to record their reactions.

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