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 ...

The Xerces Society for Invertebrate Conservation says, along the California coast, 4.5 million monarchs overwintered in the ...

The plight of the monarch butterfly could cost farmers a valuable tool in the fight to protect crops from weeds and pests. An effort is underway to list the monarch butterfly as threatened under ...

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.

They often fly more than ... Scientists assess US monarch populations each winter by measuring the area they occupy in this fir grove in Mexico, and by counting butterflies in coastal California ...

Monarch butterflies are migrating through San Antonio, laying eggs on milkweed, while other species like the Gulf fritillary ...

Beauty on the Wing: Life Story of the Monarch Butterfly is available to stream on pbs.org and the free PBS App, available on iPhone, Apple TV, Android TV, Android smartphones, Amazon Fire TV ...