Ground squirrels are a keystone species. I know what you are thinking: “That means Gunn High School is the epicenter of the ecological universe.” Or maybe “How is it that mounds of dried grass studded with ankle-twisting holes are a paragon of ecological virtue?” I had those same questions after I came across the claim. It made me wonder who determines which species are “keystone”, how the determination is made, and whether, perhaps, we aren’t being picky enough.