How does caterpillar become butterfly

Puss moth caterpillars in the US are said to have such a terrible poison in their stings that they will make your bones hurt. While the cinnabar moth caterpillar warns of its concentrated toxins through bright and contrasting colours. The life of a caterpillar is focused on growing and eating. The amount they eat will affect their chances as an adult, and therefore the likelihood they will have offspring.

Most caterpillars go from egg to pupa in weeks. However some, like the grizzled skipper, take two months. Those that overwinter as caterpillars can stay in this form even longer, and the most extreme example has to be the banded woolly bear caterpillar. This caterpillar lives for up to fourteen years in its larval form.

It has adapted to freeze solid during the winter, without damaging its body, unfreezing in the spring and continuing to eat. The pupa is a largely stationary stage in which the caterpillar completely alters its anatomy. In butterflies, the pupa is commonly called a chrysalis, though both words can be used. To become a pupa, the caterpillar must rid itself of its old skin, moulting a final time.

The way different species go about the pupal stage varies quite significantly. For all caterpillars, it requires their old skin to be shrugged off and a new form to appear. The outside is often relatively featureless, though the outline of some limbs and bodyparts can sometimes be made out.

Many butterfly species they will attach themselves to a plant with silk and then hang upside down, wriggling themselves out of their outer layer of skin. Others will face upwards instead and wrap a small line of silk around their bodies to keep them from toppling over once their limbs are no longer able to hold them.

Many moth species will add an extra layer of silk around their pupa, known as a cocoon. The most famous cocoon maker is the silkworm, which spins a dense layer of silk around its body. This silk has long been harvested by humans for use in the production of expensive fabrics. Cocoons can provide an additional layer of protection from the elements, or parasites. Although we tend to think of pupa hanging from plants and other vegetation, many species pupate on the ground or in the soil.

As many of these pupae are brown, they become very hard to spot amongst winter leaves or dirt. Some butterflies have a clever way to make sure they are taken extra care of during these vulnerable months. The chalk hill blue caterpillar feeds on plant species, but when it becomes a pupa, it releases scents that encourage ants to collect it and bury it somewhere safe. Many chrysalis are well camouflaged, their forms resembling dead leaves or thorns.

Some moth caterpillars cover their cocoons in bits of dirt or vegetation to keep it hidden, while others rely on tucking it away out of sight. For all species, this is a risky time. Some pupae can move or make sounds if disturbed, to scare away predators. The pupa of the green hairstreak makes a squeak so loud it is audible to human ears. Also read: What do Caterpillars Eat? Before hatching, when a caterpillar is still developing inside its egg, it grows an imaginal disc for each of the adult body parts it will need as a mature butterfly or moth—discs for its eyes, for its wings, its legs and so on.

In some species, these imaginal discs remain dormant throughout the caterpillar's life; in other species, the discs begin to take the shape of adult body parts even before the caterpillar forms a chrysalis or cocoon. Some caterpillars walk around with tiny rudimentary wings tucked inside their bodies, though you would never know it by looking at them. Once a caterpillar has disintegrated all of its tissues except for the imaginal discs, those discs use the protein-rich soup all around them to fuel the rapid cell division required to form the wings, antennae, legs, eyes, genitals and all the other features of an adult butterfly or moth.

The imaginal disc for a fruit fly's wing, for example, might begin with only 50 cells and increase to more than 50, cells by the end of metamorphosis. Depending on the species, certain caterpillar muscles and sections of the nervous system are largely preserved in the adult butterfly. One study even suggests that moths remember what they learned in later stages of their lives as caterpillars.

Getting a look at this metamorphosis as it happens is difficult; disturbing a caterpillar inside its cocoon or chrysalis risks botching the transformation. But Michael Cook, who maintains a fantastic website about silkworms , has some incredible photos of a Tussah silkmoth Antheraea penyi that failed to spin a cocoon. You can see the delicate, translucent jade wings, antennae and legs of a pupa that has not yet matured into an adult moth—a glimpse of what usually remains concealed.

Ferris Jabr is a contributing writer for Scientific American. Follow Ferris Jabr on Twitter. Already a subscriber? A whopping 75 percent of known insects —among them bees, beetles, flies, and moths—develop in four stages: egg, larva, pupa, and adult. Most striking about complete metamorphosis is how different the larva looks and behaves from the adult.

Watch a time-lapse video of a caterpillar becoming a butterfly. Other species, such as grasshoppers and dragonflies , experience incomplete, or simple, metamorphosis, which involves three life stages—egg, larva or nymph, and adult or imago. The nymphs look like tiny adults, eating and shedding their skins until they reach adulthood. Nearly all insects start out as eggs and then hatch into larvae.

Caterpillars are a type of larvae that many people are familiar with, but others resemble worms or tiny insects, as occurs in ladybugs aka ladybirds. Each stage of molting is called an instar, and some insects molt up to five times before moving onto the next stage.

Metamorphosis changes almost everything. In insects that undergo incomplete metamorphosis, the larvae are called nymphs. Many, such as grasshoppers, look and behave much like tiny versions of the adult insects. Others, such as leafhoppers , look a bit different from adults, with small wing buds. But these insects eat the same things as adults and move the same way, going through multiple molts until they mature. Cicadas can take 17 years to metamorphose into adulthood , spending most of that time underground.

After shedding their final instar, insects that experience complete metamorphosis become pupae. In some cases, pupae enclose themselves inside a hard cocoon, or chrysalis, which butterflies and moths make from their own silk. Others deploy different techniques. After a worm-like larval stage of nearly two years, Hercules beetles of the American tropics store up enough feces to form sturdy cocoons. It's odd that these giant beetles make a cocoon at all, explains Richard Jones , an author and entomologist in the U.

K not affiliated with a university or organization. Other beetles, such as the eastern firefly of the United States, nestle in soil. Some caddisflies build cases out of rocks and shells from their native rivers and streams and pupate inside after sealing them up. Honeybee larvae resemble white grubs, pupating inside sealed cells within the honeycomb. After emerging from its chrysalis, a newly minted butterfly may look wilted—its wings are wet and need a couple of hours to expand before taking flight.