About Monarchs

Each year, over the course of a few generations, monarchs make an incredible journey across North America to overwintering sites in Mexico and California.

From egg to adult, monarchs undergo a fascinating metamorphosis. The life cycle of monarchs is well-known and inspirational, making these iconic insects ideal for research and science education.

Monarchs rely on specific habitats to shelter and feed their larvae and to provide nectar to fuel adult movement and survival.

The downward trend in the monarch population is due to factors including the loss in abundance and quality of breeding and overwintering habitats.

Monarchs are native to North and South America but spread throughout much of the world in the 1800s (though recent analysis supports earlier dispersal (Kronforst et al. 2014).

If you observe adult monarchs in the wild, you will notice many differences between them. Some are larger than others, and some look very tattered and worn, while others look fresh and new.

In this section, we’ll explore the amazing process that ends in egg laying by female monarch butterflies.

Monarchs, like other insects with complete metamorphosis, undergo a development process that appears very different from humans.

In this section, learn about how cardenolides in milkweed benefit monarchs, how milkweeds and monarchs vary in the type and concentration of cardenolides they contain, and how milkweed defenses affect monarch larvae.

The science of systematics gives us the tools to communicate clearly about the natural world and imposes order by describing the relationships between living organisms.

Butterfly sensory systems are very different from humans. This page introduces important organs associated with sensory systems at different life stages and explains how a butterfly uses its senses to navigate through its world.

Why Monarchs? While monarchs are intrinsically important, conserving them matters for more than their own protection.