Process Description of the Life Cycle of a Butterfly INTRODUCTION ...

Process Description of the Life Cycle of a Butterfly
INTRODUCTION
Subject
Butterflies are winged insects that evolved from moths about 150 million years ago (Feltwell 1).
Since that time thousands of species have evolved, becoming an indispensable part of our planet’s
ecology. Butterflies provide a food source for a myriad of insects and animals, and have influenced
the evolution of flowering plants (Douglas 177). This ecological importance extends throughout its
entire life cycle.
Audience, Purpose
The life cycle of the common butterfly is a complex and fascinating process, yet one most people are
unaware of. This report is intended to offer general information on the life cycle of a butterfly for
those interested in, but unfamiliar with, this process.
Scope
This report will explore the four stages of butterfly development: egg, larva, pupa and adult.
COLLECTED DATA
The Egg
The first stage in the butterfly life cycle is the egg. These eggs come in a variety of colors and shapes,
from spheres to cones to discs, and the shape of the egg can often identify the species. Butterflies
might lay as few as 100, or as many as 2000 eggs on or near food plant (Douglas 9). Once they are
laid, the fertilized cells multiply very quickly. Nourishment is provided from a food supply in the egg
itself . and oxygen and carbon dioxide are exchanged through pores or ducts in the egg shell. The
eggs can hatch in as little as three days or suspend development until the following spring (14).
The Larval Stage
Like butterfly eggs, the larva, more commonly known as caterpillars, also come in many shapes and
sizes. Most are wiener shaped but others look like slugs, and still others are covered with fur or
spines. Whatever the differences, caterpillars do have common characteristics. They each have a well
defined head with tiny antenna, mouth parts, and six pairs of primitive eyes (14).

The body of the caterpillar has thirteen segments. Three of the forward segments contain the clawed
walking legs, at least one pair to each segment. The five pairs of grasping legs are located on five of
the ten rear segments (see figure 1). Most of the internal portion of the larva is dedicated to digestion
(Douglas 16).
The sole purpose of the caterpillar is eating. Immediately after hatching it begins to consume huge
quantities of food. This singularity of purpose results in an extremely rapid weight gain. Mass
consumption of food is necessary for the changes that will occur during the pupal stage (18).
The Pupal Stage
Figure 1 The Butterfly Larva
Source: Golden Book of Insects
The pupal stage occurs when the larva anchors itself to a branch or leaf, loses its outer skin and forms
a hardened case called a pupa, around its internal organs (see figure 2). The purpose of this casing is
to protect the larva as it undergoes the changes that transform it into a butterfly. The pupal stage is
the bridge between larva and adult. In this stage complex biological changes are taking place inside
the pupa. The larva is being chemically dismantled and its larval structures (legs, organs, antenna,
etc.) are being rebuilt into adult structures. This process may take months or only a few days (Douglas
25).
Figure 2. The Pupa
Source: Golden Book of Insects

Adult
After the pupal stage is complete the adult butterfly will emerge from the pupa with shriveled wings.
The wings are quickly pumped full of liquid from the butterfly’s body, causing them to expand and
stiffen into usable wings. At this stage the butterfly becomes the familiar brightly colored and intricately
decorated insect that nearly everyone will recognize.
The adult butterfly concerns itself mainly with mating and laying eggs. Soon after emerging from the
pupa, butterflies begin to search out a mate to insure the production of the next generation. A butterfly
lives in the adult form from two weeks to ten months and most of this time is divided between
mating and consuming the nectar of flowers. After the female has mated, she locates an appropriate
site and lays her eggs. Then the entire cycle repeats itself.
CONCLUSION
The four stages of the butterfly life cycle: egg, larva, pupa and adult, encompass radical biological
and chemical transformations which are excellent examples of the hidden miracles of nature (see
figure 3).
Figure 3. The Monarch Butterfly

Works Cited
Douglas, Laura. The World of Butterflies, Buffalo, NY: Textile Bridge Press, 1990.
Feltwell, John. Butterflies and Moths, New York: Dorling Kindersley, 1993.