Bees are among the most sensitive and hardest-working creatures in nature.
A mysterious ailment, however, is causing the great pollinators to lose their way home. The disorder, called "colony collapse,'' has resulted in the deaths of millions of honeybees worldwide and up to half of the 2.5 million colonies in the United States.
The chief suspect, say many scientists, is the most commonly used insecticide on the planet: imidacloprid.
Launched in 1994 by Bayer, the German health care and chemical company, imidacloprid is used to combat insects such as aphids that attack more than 140 crops, including fruits and vegetables, cotton, alfalfa and hops. Sold under various brand names, such as Admire, Advantage, Gaucho, Merit, Premise and Provado, imidacloprid also is manufactured for use on flowers, lawns, trees, golf courses and even pets in the form of flea collars.