It’s been hypothesized that pesticides are the source of the global collapse of bee populations, but there had been no controlled experiments demonstrating correlation. A French government group performed just such an experiment and found that, indeed, colonies exposed to low levels of imidacloprid (a common, Bayer-developed insecticide) failed to thrive. They were 100–200% more likely to die while away from their nests, possibly because imidacloprid damages their ability to navigate back. →