On a steamy June evening, Curtis Eckerman embarks on a mothing expedition in the Bauerle Ranch greenbelt, in far South Austin. Towing a wagon full of supplies, he follows a narrow trail that leads between mesquite trees and into a secluded oak grove suffused with golden late-afternoon light. Eckerman, the chair of the biology department at Austin Community College, parks the wagon and begins to wrap a tree trunk in white cloth. Next he suspends a battery-powered ultraviolet light from a low branch. He’s optimistic we’ll see lots of different moths tonight; it’s been a warm, humid day, conducive to plant growth and, by extension, activity by plant-eating creatures. The oak grove is full of frostweed, persimmon trees, and various grasses, each vital to different…