Butterfly Life History

BUTTERFLIES are insects which undergo four distinct stages of development ~ the egg, larva or caterpillar, pupa or chrysalis, and the adult or imago. The duration of each stage, and of the whole life of the creature, varies with species.
     In the tropics, this development is not interrupted by cold weather. The eggs hatch several days or more after they are laid, and the hatchlings eat the eggshells as their first meal. The caterpillars then feed intensively on food plants, which may be a specific host, or a group of related species, or plant species in unrelated groups.
     The caterpillars, which have been described as eating machines, grow rapidly and moult four or five times, i.e. they shed their old, “already too tight” skin to accommodate growth. The stage between moults is known as instar. Depending on species, the caterpillars attain full growth in two to eight weeks and proceed to change into pupae.
     The pupal stage lasts from one to several weeks, depending on species. Outwardly this seems a dormant stage, but dramatic changes are actually taking place inside the pupal case. The tissues of the organism break down and “re-constitute” to make the adult butterfly.
     The adults emerge, after pushing through their pupal cases, with limp and wet wings. These dry out in a few hours. When they are ready for flight, they take off to seek food and mate. Butterflies may live for up to a month.