“We found that it took triple the dose of one pesticide to have the same lethal effect on fruit flies at the time of day their defenses were strongest, compared to when they were weakest,” said Louisa Hooven, a postdoctoral fellow in the OSU Department of Zoology and lead author on the study. “A different pesticide took twice the dose. This makes it pretty clear that the time of day of an exposure to a pesticide can make a huge difference in its effectiveness.”