For thousands of years, millions of monarch butterflies have migrated from the northern U.S. and Canada to Mexico for the winter. But exactly how they know where to go is still a mystery.

Monarchs traveled to a remote part of Mexico, a journey they've made for thousands of years, and wintered there. Now tens of millions of the butterflies are on an epic aerial journey back north.

Scientists have recently mapped the painted lady butterfly's annual flight from equatorial Africa to northern Europe and back ...

A new butterfly species, Satyrium curiosolus, was discovered in a recent study at Blakiston Fan in Waterton Lakes National Park, Alberta. It has unique evolutionary history, having likely remained in ...