Monarch butterflies use internal compass for epic migration
The compass flips in cold temperatures, UC biologists find
Earth.com highlighted a new study by the University of Cincinnati that found monarch butterflies have an internal compass for its epic migration that flips when the temperatures plunge.
This changing polarity helps butterflies prepare for the return trip on their migration back and forth across North America.
The study was published in the journal PLOS One.
UC Associate Professor Stephen Matter, former UC Assistant Professor Patrick Guerra, now at the North Carolina Department of Environmental Quality, and UC graduate student Samuel Shively-Moore helped explain how monarchs navigate over thousands of miles on their way from their northern range as far away as Canada to their overwintering roosting sites in the mountains of central Mexico.
Monarch primarily use a sun compass calibrated to the number of hours of daylight as a compass. But monarchs also use a magnetic compass to stay the course.
But researchers found that butterflies exposed to 24 days of cold temperatures like the kind they experience in their overwintering grounds reorient to the north, suggesting their internal compass is recalibrated by the cold.
“Our discovery that coldness triggers the northward flight direction in spring re-migrants solves one of the long-standing mysteries of the monarch migration,” Guerra told Earth.com.
Their findings raise questions about how rising temperatures might affect the monarchs' navigational cues.
Featured image at top: UC biologists are unlocking secrets of the monarch butterly's epic migration. Photo/Michael Miller
Former UC Assistant Professor Patrick Guerra found that the monarch butterfly's internal compass is influenced by temperature. Photo/Lisa Ventre/UC
Related Stories
UC professor leads film students to the future
April 6, 2026
As a kid, at the age of 10, Marty Schiff’s dad gave him a Kodak Brownie movie camera, and that led to a lifetime of creating stories on film. He spent his summers with that camera, making eight-millimeter movies, with a camera that taught him how to thread a projector, change the film in a closet, and tell stories with the medium he loved. “I always wanted to go to Hollywood,” Schiff says. So later he did, with $200 in his pocket, and began a career that has spanned acting, directing, producing—pretty much everything with the exception of costumes (“I’m not really good with a sewing machine,” he says).
High Court offers protections for therapy speech
April 5, 2026
Jennifer Bard, a professor in the Donald P. Klekamp College of Law and the UC Department of Internal Medicine, spoke with journalists about the US Supreme Court ruling granting first amendment protections for speech offered during therapy sessions.
Scientists discover how snakes stand upright without limbs
April 3, 2026
Smithsonian magazine highlights a study co-authored by UC Professor Bruce Jayne, an expert in snake locomotion, about how snakes stand upright without arms or legs.