A butterflies typical behavior is as follows: 

Life cycle: From egg to adult, butterflies undergo a series of physical transformations known as metamorphosis. After mating, the female butterfly lays her eggs on a caterpillar food or “host” plant. The eggs can hatch within a few days, or within months or even years, depending on whether or not conditions are right.

After hatching, a caterpillar begins to eat the host plant.  The caterpillar sheds its skin several times during this stage. It then seeks a sheltered spot, suspends itself by silken threads and sheds one last time to reveal skin that will harden to form the chrysalis or pupa. Days, months or even years later, depending on the species, a fully developed winged adult emerges from the chrysalis and the cycle begins anew.

Defense Mechanisms: Many butterflies have developed interesting ways of defending themselves from predators. One method is disguise, or “cryptic coloration”, where the butterfly has the ability to look like a leaf or blend into the bark of a tree to hide from predators.  Another method is chemical defense, where the butterfly has evolved to have toxic chemicals in its body. These species of butterfly are often brightly colored, and predators have learned over time to associate their bright color with the bad taste of the chemicals.