There has never been a genetically modified organism in nature. It belongs to a newborn alien species. It is more competitive than natural organisms because of the special genes in its body. For example, crops implanted with insect-resistant genes will be more resistant to pests and diseases than normal crops. In the long run, GM crops will replace the original crops and cause species extinction. This problem, however, is difficult to detect at the beginning of the development of GMOs, and it may take many years before it becomes apparent, but by the time the problem appears, it will be too late.

There have been examples of this in history. For example, there were no rabbits in Australia, but when they were introduced, their numbers doubled and they ate all the plants, causing major problems for the ecosystem. About a century ago, the introduced mimosa spread rapidly in Australia, greatly crowding out other plants around it. Predatory fish and tortoise-headed flower snakes introduced in the U.S. ate local fish, and in 1959, the Nile perch was introduced to Lake Victoria in the U.K. for people to fish for pleasure. Unexpectedly, decades later, the river perch destroyed the local ecosystem and the native fish suffered extinction.