By Siyan (Jen) Huang

Each year, swarms of North American monarch butterflies make their way from Canada and the United States to central Mexico before the fall of winter. The monarchs don’t live long enough to make a return trip, so how do they know when and where they should go?

Ayse Trolander, a graduate student at the University of Chicago Department of Ecology & Evolution, is trying to solve the mystery of monarch migration. Her experiments point to something in the genetic makeup of the butterflies that prompts and guides them to head south to their winter home.