When eight-year-old Hugo Deans discovered a handful of BB-sized objects lying near an ant nest beneath a log in his backyard, he thought they were a type of seed. His father, Andrew Deans, professor of entomology at Penn State, however, knew immediately what they were—oak galls, or plant growths triggered by insects. What he didn't realize right away was that the galls were part of an elaborate relationship among ants, wasps and oak trees, the discovery of which would turn a century of knowledge about plant-insect interactions on its head.