One argument that you’ll often hear from supporters of GMOs is that people have been creating seed hybrids and selecting for certain genes for nearly as long as farming has been around…and today’s genetically engineered crops are no different. It sounds like a pretty good argument, but once you understand the science behind natural propagation, hybrid seeds, and genetically modified seeds, you’ll see that the argument is based on ignorance rather than science.
In the history of farming, there have been different ways that people have manipulated seeds in order to produce the result they’re looking for. In looking at a brief overview of the three basic ways to create seeds, you’ll quickly see that genetic engineering is far different from traditional methods of trait selection or seed production.
Open pollination is the natural means by which seeds propagate. Pollen travels from place to place on the wind or through pollinators like butterflies and bees, and seeds develop. The resulting plants will be very similar, but will vary slightly—in other words, they won’t be clones of the original so mutations and changes can occur, but they’ll be a very similar plant. Seeds that are created in this way are called “heirloom” seeds.
Open pollination is what happens naturally on a daily basis, and it can also be manipulated by human farmers. To breed plants for a certain trait using open pollination, a gardener can isolate a certain patch of plants so that it won’t be cross-pollinated. Over time, you can change some of the aspects of the plants in this way…that’s how much of our current produce developed, in fact. Natural pollination produces plants, the plants produce seeds, and the seeds are sold to produce similar plants.
Heirloom plants produce seeds that, when harvested and planted, produce another generation of very similar plants.
If you were to explain open pollination in terms of the animal world, this would be like two stray cats meeting up and creating a litter of kittens: the offspring of the cats would vary slightly in size, color, and whisker length but they would still be cats, and most of the kittens would look like their mother, father, or a blend of both.
Another method of manipulating seeds that have been in use for generation is the hybrid. Hybrid plants can be created in the wild naturally when pollens cross—but humans can also create hybrid seeds by purposely choosing the plants they want to combine. This will only work with similar plants, which is why we have a wide variety of apple types (from Granny Smith to Pink Lady) but we don’t have tomato-apples or cranberries.
By picking traits that make a healthy, hearty plant or produce pleasing fruit, seeds can be created by purposefully pollinating plants that have been carefully selected. This can be done in low-tech, easy ways (for example, by keeping the two types of plants you’re combining together in an enclosed space) or it can become much more technical and be done in a lab. Either way, however, the genetic “manipulation” that’s occurring never exceeds that which is possible in nature, and the genes of the plants are simply mixed as they might do in the wild.
Hybrid seeds, unlike heirloom, will produce the plants and fruit they’re created for in the first generation—but if you were to plant the seeds from that crop, you wouldn’t end up with similar plants. Instead, you’d have a variety of different plants that might express traits that were not present in the hybrid but are present in the gene pool…that’s why “volunteer” tomatoes from last year’s plants don’t produce as well as the original. You’ll have to buy a new packet of seeds to get the results you expect, rather than saving seeds from last year’s crop.
If we think of hybrids in terms of cats, this would be like pairing up a housecat and a wildcat…Bengal cats are a blend of a small Asian leopard cat and a typical housecat. These cats would have been quite unlikely to have encountered one another in the wild, and would likely not have mated. However, they are both still cats—and the resulting litter of kittens is a larger, spottier, and slightly wilder version of a housecat.
Genetically Modified Seeds
Now enter the genetically modified seed. While both heirloom seeds and hybrid seeds are created with plants that are genetically compatible, GMO seeds are created in a lab using genes from plants that could never be combined naturally. In fact, they are created not just from different species, but from different organisms entirely. That means that the DNA in a genetically modified seed might not even come from a plant!
For example, one of the biggest GMO crops is Bt corn. This corn is engineered in a lab to contain both plant DNA and bacteria DNA, a combination that would not be possible in nature. The bacteria that’s been spliced into the seeds kill a certain kind of pest. There are no natural means by which a plant like this would develop in the wild, and it can’t be recreated by a farmer.
GMO seeds are regulated by the companies that create them, in order to ensure that the company receives revenue from every seed sold. However, although the seeds themselves could not have developed naturally, the can cross-pollinate—which means that, even when they are not wanted, they can spread. Farmers have been sued by Monsanto for having GMO corn in their fields, despite the fact that they are not intending to grow mutated corn.
If we’re using our cat analogy for GMOs, just about anything goes. Let’s say a cat owner has had trouble finding their pet at night. In a lab, genes from glow-in-the-dark jellyfish might be spliced into cat embryos, and the resulting kittens glow in the dark—allowing their owners to find them easily when it’s time to come in at night.
Does this sound crazy, impossible even? The images above are actual photos of cats created in just this way.
Anyone who argues that GMOs are simply another way of natural propagation either does not understand natural propagation or is assuming that you don’t. There is no comparison between seeds (or animals!) created in a lab by forcing incompatible DNA together and seeds created using similar plants and natural means—and we have no way of knowing what the long-term consequences of manipulating genes in this way might be.