Genetically Modified Organisms and Evolution

When it comes to the long-term effects of GMOs, there's a lot we don't know

GMOs may affect evolution
Genetic modification of tomatoes. Getty/Coneyl Jay

While different organizations seem to have differing opinions on this widely used technique in the world of nutrition, the fact is that agriculture has been using GMO plants for decades. Scientists believed it would be a safer alternative to using pesticides on crops. By using genetic engineering, scientists were able to create a plant that was inherently immune to pests without the harmful chemicals.

Since the genetic engineering of crops and other plants and animals is a relatively new scientific endeavor, no long term studies have been able to produce a definitive answer on the question of safety of the consumption of these modified organisms. Studies are continuing into this question and will scientists will hopefully have an answer for the public about the safety of GMO foods that is neither biased nor fabricated.

There have also been environmental studies of these genetically modified plants and animals to see the effects of these changed individuals on the overall health of the species as well as the evolution of species. Some concerns that are being tested are what effects do these GMO plants and animals have on the wild type plants and animals of the species. Do they behave like invasive species and try to out compete natural organisms in the area and take over the niche while the "regular", non-manipulated organisms begin to die out? Does the changing of the genome give these GMOs a sort of advantage when it comes to natural selection? What happens when a GMO plant and a regular plant cross pollinate? Will the genetically modified DNA be found more frequently in the offspring or will it continue to hold true to what we know about genetic ratios?

If the GMOs do happen to have an advantage for natural selection and live long enough to reproduce while the wild type plants and animals begin to die out, what does this mean for the evolution of those species? If that trend continues where the modified organisms seem to have the desired adaptation, it stands to reason that those adaptations will be passed down to the next generation of offspring and become more prevalent in the population. However, if the environment changes, it could be that the genetically modified genomes are no longer the favorable trait, then natural selection could swing the population in the opposite direction and cause the wild type to become more successful than the GMO.

There have not been any definitive long-term studies published yet that can link the advantages and/or disadvantages of having organisms that have been genetically modified just hanging around out in nature with wild plants and animals. Therefore, the effect GMOs would have on evolution is speculative and has not been fully tested or verified at this point in time. While many short term studies do point to the wild type organisms being affected by the presence of the GMOs, any long term effects that will impact the evolution of the species is yet to be determined. Until these long term studies have been completed, verified, and supported by evidence, these hypotheses will continue to be debated by scientists and the public alike.