For millennia, humans have modified plant genes in order to develop crops best suited for food, fiber, feed, and energy production. The earliest efforts, far predating Gregor Mendel's 19th-century discoveries on trait inheritance, involved the selective breeding of plants with desirable characteristics, but the recombination of DNA in offspring was random. Consequently, plant breeding often took decades and frequently yielded crop varieties with unforeseen and undesirable properties. Today, conventional plant breeding remains inherently random and slow, constrained by the availability of desirable traits in closely related plant species. In contrast, agricultural biotechnology employs the modern tools of genetic engineering to reduce uncertainty and breeding time and to transfer traits from more distantly related plants.Arguments in support of and in opposition to the use of genetically engineered seeds have changed little since the technology emerged in the 1980s. On one side, critics express concerns that the technology imposes negative environmental effects and jeopardizes the health of those who consume the "frankenfoods." On the other side, supporters emphasize potential gains from boosting output and lowering food prices for consumers. They argue that such gains are achieved contemporaneous with the adoption of farming practices that lower agrochemical use and lessen soil