Butterfly Facts

Butterflies ['bŭ-tûr-flīz]

Insects with two pairs of large, brightly colored wings.


Close up of swallowtail butterfly perched on flowers and sucking nectar

Butterflies are one of the most diverse and most recognizable creatures in the insect world. They are famous for their symmetrical wings that often display amazing colors and patterns. But the life of a butterfly is far more than their beautiful wings. The butterfly's life is one of complex change.

Fritillary Butterfly

The butterfly's scientific name is Lepidoptera which is Greek for "scale winged." They have three body parts: the head, the thorax, and the abdomen. Just like the other members of the insect family, butterflies have 6 jointed legs which are joined to the thorax. The wings are attached to the thorax also. There are 4 wings: two forewings and 2 hindwings. The head holds the eyes and the mouth, or proboscis, which is a tube that they use to drink nectar from flowers. Their eyes are what are called compound eyes and have many, many lenses. They also have antennae on the tops of their head which they use for smell and for feeling things. Their body is protected in a hard covering known as an exoskeleton since they don't have an interior skeleton like a human's.

Butterfly vs. Moth

Atlas moth close-up, also known as snakehead butterfly, displaying beautiful wingspan

Butterflies and moths are often confused. They do look similar and have similar body structures, but they are two distinctly different creatures.

Butterflies are day feeders so their wings are colorful. The moth, which feeds at night, has a more neutral color scheme so that they can hide themselves from predators and blend into the colors of the night.

Butterflies' bodies and antennae are slim and sleek. Sometimes the antennae have small knobs at the ends. The moth tends to have a fatter, furry body and antennae. Their antennae can even take on a featherlike appearance. Notice the differences in these two specimens.

Life Cycle

Butterflies lay very small eggs that can be almost invisible to the naked eye. These eggs are usually laid on the underside of a leaf to protect them from rain and wind. When the eggs hatch, a small caterpillar begins to eat this same leaf. The caterpillar is known as the larva stage of life.


The caterpillar eats and grows and eats and grows. As it grows, it sheds its skin several times. Once the caterpillar is as big as it will get, it is ready to form its chrysalis. At this stage, the caterpillar crawls to a sheltered location and hangs itself upside down by spinning a small cobweb-like material to attach itself to a branch or other structure.

Common Mormon cocoon on citrus plant branch, closeup macro shot, against a black background

As it sheds its skin one last time, the caterpillar's outer skin is now a special container where inside it will change from caterpillar to butterfly. This stage is known as the pupa. Inside this chrysalis, exciting changes are taking place.

When it is time, the adult butterfly will work very hard to emerge from its chrysalis. As it unfolds its wings, blood is pushed into the outer sections of the butterfly's body and the insect is ready in a few days to fly away to find food, a mate, and lay eggs itself. And then the process, known as metamorphosis, begins all over again.

What They Eat

Monarch butterfly

Butterflies are herbivores. They typically eat from plants, but that could be any variety of forms including grasses, leaves, or nectar from the center of the plant's flowers, depending on the stage of their life. Different butterflies are attracted to specific plants. The Monarch caterpillar enjoys milkweed leaves; Painted Lady butterflies drink the nectar from Thistle. In Idaho, the Western Branded Skipper loves the Goldenrod flower.


Colorful European Peacock butterfly

Butterflies are cold-blooded which means that they cannot adjust their own body temperature for the weather conditions. In order to survive, they must live in generally comfortable temperatures where it does not get too hot or too cold.

Brimstone Butterfly

Butterflies are one of the most numerous members of the insect world and live on all of the continents except Antarctica. Many species migrate with the food or weather conditions and can travel thousands of miles in order to locate the best resources. When flowers die off during the winter, butterflies will fly south to find new ones.

The butterfly lives a very short life. The Brimstone Butterfly is said to be the longest living with a 9-10 month life span.

Monarch Butterfly

The Monarch Butterfly is recognized as the state insect or butterfly for seven different states in the U.S. This butterfly is very familiar to most people because of its black, white, and orange coloring during its adulthood and the distinctive black, yellow, and white stripes of the caterpillar.

The Monarch caterpillar eats the leaves of the milkweed which is a very bitter plant. Because of this, the butterflies take on this same bitterness which protects them from being eaten by birds and lizards.

Photo of Monarch butterflies flying to a tree

They are famous for their migration to Mexico and parts of California. This migration is unique in that it takes four generations for the Monarch to make this journey. The first through third generations only live about six weeks, which is not enough time to make this incredible journey. The fourth generation lives four to six months and so is able to make the trip and still have time to begin a new generation by the time springtime arrives.


Closeup shot of a viceroy butterfly on pink flowers

Many butterflies use mimicry to protect themselves from prey. The Viceroy butterfly looks very similar to the Monarch which feasts on bitter-tasting milkweed plants. This trick confuses predators into avoiding the Viceroy, thinking that it will taste bitter like the Monarch.

Closeup shot of an owl butterfly isolated on white background

Another clever-looking butterfly that uses mimicry is the Owl butterfly which has a large "eye spot" on its wings to confuse its predators into thinking it is an owl. No smart bird, lizard, or other butterfly predator would attack an owl.

Top 10 Questions

May 2012

Thanks to Dr. Paul Castrovillo, Butterfly Curator, Orma J. Smith Museum of Natural History; and Steve Burns, Director, Zoo Boise for the answers.

  1. Which butterfly is the largest?

    That would be the Queen Alexandra Birdwing butterfly. Its wingspan is about 11 inches. (From Humzza in Mrs. Hurd's class at Owyhee-Harbor Elementary School in Boise)

  2. Does a butterfly have a brain?

    Yes, a butterfly has a brain. It is attached to a long nerve cord in its body and the brain is up near its head, just like most animals. (From Paige in Mrs. Hunt's class at Cynthia Mann Elementary School in Boise)

  3. How long can butterflies fly without resting?

    Some butterflies can fly for hours and hours because they fly to where the wind can move them along. The butterflies that fly for a long distance usually use the wind for assistance. (From Taley in Mrs. McCamish-Cameron's class at Grace Jordan Elementary School in Boise)

  4. Do monarch butterflies hibernate?

    They don't technically hibernate. They fly south, land in a grove of trees, and remain mostly inactive throughout the winter. Then they wake up and fly off again, but they don't go to sleep like a hibernating animal. (From Claire in Mrs. Childers' class at Hayden Meadows Elementary School in Hayden)

  5. How many butterflies exist?

    There are about 10,000 in the world, 1,000 in the United States, and 150 in Idaho alone that are scattered throughout the state. (From Madison in Mrs. Schweitzer's class at Riverside Elementary School in Boise)

  6. How long is an average butterfly's life?

    It depends on the species that you are asking about. Some butterflies live for a few days and some live for a few months. (From Joie in Mrs. Schweitzer's class at Riverside Elementary School in Coeur d'Alene)

  7. Do butterflies die if you touch their wings?

    A person can touch a butterfly's wing and sometimes the color will rub off. This will not kill a butterfly. It can die if its wings are touched too roughly, as this could cause the veins to become broken causing it to be unable to fly. So, it all depends on how rough a person is with their touch. Most butterflies are fairly tough, and you should be able to handle them carefully without worry. (From Kayla in Mrs. Childers' class at Hayden Meadows Elementary School in Hayden)

  8. How do butterflies grow wings?

    Butterflies always have the cells for wings inside their bodies, even when they are caterpillars. When they reach the pupa part of their cycle, those cells start to grow rapidly and form wings. (From Adam in Mrs. Hudson's class at Dalton Elementary School in Dalton Gardens)

  9. Why do butterflies like milkweed plants?

    Butterflies have what are called host plants. They lay their eggs on the host plant because it is that's what the caterpillars eat. When the eggs hatch and the caterpillars come out, milkweed is one plant caterpillars like to eat. That's why you will see monarchs on milkweed plants. If you want to protect butterflies, you also have to protect their host plants. (From Hayden in Mrs. McCamish-Cameron's class at Grace Jordan Elementary School in Boise

  10. What is a butterfly's defense mechanism?

    Butterflies stay safe in a few different ways. The color on their wings can protect them by allowing them to blend into the background. There are a number of butterflies that look like leaves, bark or dead grass. Also, the ability of flight helps to keep them safe. Being able to get away can be very important to the safety of a butterfly. Then, some butterflies are poisonous like the monarch butterfly. It feeds on milkweed and there are poisons in the milkweed plant that go into the caterpillar's body and end up in the adult butterfly's body. So a predator that feeds on the monarch will have a bad taste or even get sick. The poison protects the other monarchs that weren't fed on. (From Jake in Mrs. Childers' class at Hayden Meadows Elementary School in Hayden)