This chapter explores the role of genetic diversity in crops. Using hybrid corn as an example, it discusses selection—the genetic narrowing that accompanies gains in traits like yield and disease resistance—and the ecological and evolutionary consequences of genetic uniformity in crops. In the activity, students re-enact a class action lawsuit from the 1970's in which farmers sued corn seed companies because of an epidemic caused by lack of genetic diversity in crop. Through acting as the trial's witnesses, students explore social, political, and economic consequences, as well as the ecological and evolutionary pressures, caused by lack of genetic diversity.