How Does a Caterpillar Turn Into a Butterfly?
Have you ever wondered how does a caterpillar turn into a butterfly? Do you know about the four stages of the butterfly’s metamorphosis? Let’s take a look at how a caterpillar turns into a butterfly and what this means for the little caterpillar, because the question should really be “how does a butterfly become a butterfly?”
First, not all caterpillars turn into butterflies. Some turn into moths instead. No matter what, all caterpillars go through the same four stages: egg, larva, pupa and adult. Each stage has different goals and time lengths. For example, the monarch butterfly completely changes in about one month.
These transformations are also called metamorphosis, which is Greek for “transformation” or “change in shape.” There are actually two types of metamorphosis for insects: incomplete and complete.
Incomplete metamorphosis is when the young insect looks like a small version of the adult insect. You often see this with cockroaches, crickets, dragonflies, grasshoppers and termites. Complete metamorphosis is when the young insect looks different from the adult insect and must change drastically to look like the adult. Bees, beetles, butterflies, moths and flies undergo complete metamorphosis.
The butterfly’s life starts in a small, round or oval egg. The shape varies depending on the butterfly type. Most butterflies lay their many eggs on leaves. The eggs attach to the leaves with an adhesive fluid.
A mother butterfly can lay hundreds of eggs at one time, as many will not make it to the final stage of metamorphosis.
Once the butterfly hatches from the egg, it becomes a larva. However, this larva stage is actually when the butterfly is in caterpillar form. The tiny caterpillar has small eyes and short legs and antennae. It also has bundles of cells called imaginal discs that are waiting to turn into butterfly features, including long antennae and legs, as well as wings. However, the imaginal discs are prevented from growing by a constant source of juvenile hormones. These hormones will eventually trigger the third stage.
The caterpillar spends most of this time eating, including the leaf it was born on. In fact, caterpillars can be quite picky when it comes to what leaf to eat. This is why it is vital that the butterfly lays the eggs on a leaf the caterpillar will eat. For example, monarch caterpillars only eat milkweed.
Once the caterpillar eats, it grows – about 100 times more than when they first hatched. Some internal organs begin to change, though the imaginal discs continue to stay dormant. Monarch caterpillars reach full growth after about two weeks of eating.
Since their exoskeletons don’t stretch, they grow by molting, or shedding their skin, several times, like a snake. The hormone ecdysone causes the molting.
During this third stage, the caterpillar is now ready for the next stage. Once the caterpillar is done eating and growing, there is a lack of the juvenile hormones, which causes the caterpillar to form a silk cocoon or shiny chrysalis around itself and begin radically transforming into a gorgeous butterfly. The cocoon is often hidden under branches, in a bunch of leaves or even underground.
This transformation is called complete metamorphosis, which we discussed above. From the outside, nothing appears to be happening, but inside is completely different.
The caterpillar dissolves into a soup-like substance using enzymes triggered by hormones. Its tissues, limbs, organs and imaginal discs then begin changing. The discs move to their correct positions, and the caterpillar starts taking a new shape as a butterfly.
It sprouts new colors, wings, long legs and antennae, better, larger eyes and other adult butterfly features. The mouth changes from a chewing mouth into a proboscis that sips nectar, as butterflies don’t eat solid food.
The metamorphosis takes place over a few weeks or months, and the caterpillar transforms into a completely new-looking insect.
The finished product and final stage end with a butterfly. The newly turned butterfly will break free from its cocoon. It will take some time to stretch its long legs and antennae and pump hemolymph (the blood-like substance of insects) into its wings so it can fly. The butterfly must also wait for the wings to dry and grow to their full size.
Once that happens, the butterfly will fly off and find a new mate to start the process all over again. Some butterflies only live a few weeks while others can last for months.
Butterfly Life Cycle
The butterfly and moth develop through a process called metamorphosis. This is a Greek word that means transformation or change in shape.
Insects have two common types of metamorphosis. Grasshoppers, crickets, dragonflies, and cockroaches have incomplete metamorphosis. The young (called a nymph) usually look like small adults but without the wings.
Butterflies, moths, beetles, flies and bees have complete metamorphosis. The young (called a larva instead of a nymph) is very different from the adults. It also usually eats different types of food.
There are four stages in the metamorphosis of butterflies and moths: egg, larva, pupa, and adult.
Eggs are laid on plants by the adult female butterfly. These plants will then become the food for the hatching caterpillars.
Eggs can be laid from spring, summer or fall. This depends on the species of butterfly. Females lay a lot of eggs at once so that at least some of them survive.
Butterfly eggs can be very small.
The next stage is the larva. This is also called a caterpillar if the insect is a butterfly or a moth.
The job of the caterpillar is to eat and eat and eat. As the caterpillar grows it splits its skin and sheds it about 4 or 5 times. Food eaten at this time is stored and used later as an adult.
Caterpillars can grow 100 times their size during this stage. For example, a monarch butterfly egg is the size of a pinhead and the caterpillar that hatches from this tiny egg isn't much bigger. But it will grow up to 2 inches long in several weeks.
When the caterpillar is full grown and stops eating, it becomes a pupa. The pupa of butterflies is also called a chrysalis.
Depending on the species, the pupa may suspended under a branch, hidden in leaves or buried underground. The pupa of many moths is protected inside a coccoon of silk.
This stage can last from a few weeks, a month or even longer. Some species have a pupal stage that lasts for two years.
It may look like nothing is going on but big changes are happening inside. Special cells that were present in the larva are now growing rapidly. They will become the legs, wings, eyes and other parts of the adult butterfly. Many of the original larva cells will provide energy for these growing adult cells.
The adult stage is what most people think of when they think of butterflies. They look very different from the larva. The caterpillar has a few tiny eyes, stubby legs and very short antennae. The adults have long legs, long antennae, and compound eyes. They can also fly by using their large and colorful wings. The one thing they can't do is grow.
The caterpillar's job was to eat. The adult's job is to mate and lay eggs. Some species of adult butterflies get energy by feeding on nectar from flowers but many species don't feed at all.
Flying comes in handy. The adult female can easily fly from place to place to find the right plant for its eggs. This is important because caterpillars can't travel far.
Most adult butterflies live only one or two weeks, but some species hibernate during the winter and may live several months.