Butterfly and Moth Life Cycle

Image A: Black Swallowtail caterpillar Papilio polyxenes

Image B: Anise Swallowtail chrysalis Papilio zelicaon

Image C: Monarch Danaus plexippus

Image D: Eastern Tiger Swallowtail Papilio glaucus

The butterfly life cycle includes four stages: egg, caterpillar (or larva), pupa, and adult.

After courtship and mating, female butterflies deposit their eggs, often on the undersides of leaves. Many lay their eggs on plants that will provide food for the caterpillars when they hatch.

The caterpillar is the main eating and growth stage (Image A). A caterpillar will eat until it grows too big for its skin! When this happens, it sheds its skin for a new one, and will do this four to six times as it grows.

The pupa is the transformation stage where the caterpillar turns into an adult. A butterfly’s pupa is called a chrysalis (Image B). Moths, unlike butterflies, usually enclose their pupa in a silk cocoon spun from special glands.

Flight
Butterflies are creatures of the sun and fly best when they’re warm. On cool days, they perch on rocks or bask in the sun to absorb heat and rev up their metabolism.

Monarch butterflies (Image C) migrate thousands of miles between Canada or the northern United States and Mexico each winter. While a single generation makes the trip south, monarchs returning north are shorter-lived, and it takes several generations to complete the trip north the next year.

Feeding
Adult butterflies don’t eat--they only drink. They drink liquids from flowers, juice from rotten fruit, or even sweat or liquid animal waste (Image D). Caterpillars, on the other hand, do very little but eat--leaves or other plant parts for most species. Some moths, including the luna, have no mouth parts at all as adults and cannot eat. They live just a few days, reproduce, and die.