Life Cycle Activities for Caterpillars

Egg

• Adult female butterflies and moths continuously look for opportunities to mate. They lay their eggs on the underside of leaves so the young will have a food source available as soon as they hatch. Females "taste" the leaves with their feet to determine which plants to deposit their eggs on. A glue-like substance secreted with the eggs helps them adhere to the leaves. Some species lay only one egg at a time, while others lay hundreds.

Larva

• The second stage of a caterpillar's life is the larval stage. When the eggs hatch, caterpillars emerge and immediately begin eating the plants they were hatched on. During this stage, eating is the caterpillar's only activity. As it grows, it sheds its exoskeleton, which is known as molting. Most caterpillars are herbivores, although some species do eat other insects. They are considered agricultural pests because they are capable of destroying crops with their ravenous appetites.

Pupa

• Once a caterpillar has reached its full length and weight, it turns into a pupa (also called a chrysalis, in the case of butterflies). The pupa is sometimes erroneously referred to as a cocoon. However, cocoons are the soft silk coverings that enclose some pupae. At the start of this stage, the caterpillar spins a small pad of silk and affixes itself to a branch or leaf with it. It then molts a final time. When its exoskeleton falls away, the chrysalis is exposed. The caterpillar undergoes another metamorphosis during its pupal stage. When it is ready to emerge, it must break through its hard shell.

Adult

• Scientifically known as the imago stage, adulthood is when caterpillars have transformed into butterflies or moths, depending on their species. At this point, they are sexually mature, which means they are capable of reproduction. They also have functional wings for the first time in their lives. The wings of the newly emerged moths and butterflies are folded tightly against their bodies from being inside the pupae. The insects pump blood into their wings to expand and harden them. Usually within four hours of emerging from its pupa, the butterfly or moth is flying around seeking its first mate.