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.

The annual migration of monarch butterflies is one of science's great mysteries: millions of monarchs know the correct path even though they have never made the long journey themselves. As 60 Minutes ...

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

Monarchs traveled to a remote part of Mexico, a journey they've made for thousands of years, and wintered there. Now tens of ...