Crops are genetically engineered to contain a substance that is toxic to the targeted organism. Through cross pollination there is a potential danger that the toxic substance tended for a specific crop's pest will be transferred to a different crop. The trans-gene can potentially escape into other surroundings and cross pollinate with weed plants, which result in the weed plants containing herbicide-resistant genes making them resistant to herbicides which would compromise current weed control methods. There has also been a study in 1999, at Cornell University where scientisits had concluded that the pollen from the Bt corn could harm the unintended organisms, like the Monarch butterflies but were actually aimed at the European corn borer. Another complication that comes with cross pollinating G.M. crops is the potential loss in biodiversity. Biodiversity is the range of organisms living in an ecosystem. Biodiversity could potentially be threatened if G.M. crops cross pollinates with a non-GM plant; as a result, the G.M. crop’s gene would be dominate causing there to be more genetically modified crops. And since genetically modified crops are designed to be more suitable for the surroundings, they would out compete other species of crops which will eventually lead to their complete eradication from the ecosystem. An extreme risk of the lack of biodiversity, also meaning the lack of variety of genes in crops, could result in many plant outbreaks. (3)