Monarch Butterfly and moth life cycle

Every butterfly or moth goes through four stages in its life. Each stage is very different from the others.
The cycle of stages is called metamorphosis.


The egg is the first stage in the butterfly and moth life cycle. Butterfly and moth eggs are very small and round, oval or cylindrical. Many have ribs or other tiny features. Females lay their eggs on or near the plants that will later become caterpillar food.
Monarch Butterfly Egg
Monarch butterfly egg


The larva hatches from the egg. Butterfly and moth larvae are usually called caterpillars. Caterpillars spend most of their time eating. Butterflies and moths do all of their growing when they're caterpillars, and food gives them the energy and body-building materials they need. A caterpillar's exoskeleton can't stretch or grow, so the caterpillar sheds its skin, or molts, several times as it grows.
Monarch Butterfly Caterpillar
Monarch butterfly caterpillar


When a caterpillar has finished growing, it forms a pupa. From the outside, the pupa looks as if it's resting. But inside, every part of the caterpillar is changing. Most of its organs and other body parts dissolve and re-form into the organs, tissues, limbs and wings of the adult. Butterfly pupae are called chrysalises. Many moth caterpillars spin cocoons and form pupae inside them.
Monarch Butterfly Chrysalis
Monarch butterfly chrysalis


When the pupa has finished changing, it molts one last time and emerges as an adult butterfly or moth. The adult emerges with its wings folded up against its body. The butterfly or moth pumps blood into the wings to expand them. The adult is the stage when butterflies and moths mate and reproduce. Females lay their eggs on plants or other surfaces, and the cycle starts all over again.
Freshly Emerged Monarch Butterfly
Newly emerged adult

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