For the first time, genetically modified insects have been released in the wild, in a secret location in the cotton fields of Arizona. The insects, pink bollworms, were modified by scientists to effectively destroy their own species; they are designed to be sterile, so that when they mate with natural bollworms, no offspring will result. Concern about the development is coming from an unlikely corner: the pro-GM chemical giant Monsanto. Monsanto sells genetically modified, bollworm-resistant cotton at prices farmers say are exorbitant. So the farmers are backing the GM version of the bollworm instead, which, if successful, would enable them to plant regular cotton and save money on chemical pesticides. Critics of genetic engineering have bigger fish to fry. They say the mutations could take unpredictable paths, and that the health of entire ecosystems are at stake. Although the experimental batch of bollworms has been released under netting, some dread that the experiment will go awry and the modified insects will wreak havoc in the wild.

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