Numerous orders of insects are conditionally divided into two groups. In representatives of the first group, the larvae emerging from the egg are similar to adults and differ from them only in the absence of wings. These include cockroaches, grasshoppers, locusts, bugs, praying mantises, stick insects, etc. These are insects with incomplete transformation. In the second group, eggs hatch into worm-like larvae, completely different from their parents, which then turn into pupae, and only after that adult winged insects emerge from the pupae. Such is the cycle of development of insects with complete transformation. These include mosquitoes, bees, wasps, flies, fleas, beetles, caddis flies, and butterflies.

What is metamorphosis and why is it needed?

Metamorphosis, i.e. a life cycle with a series of successive transformations is a very successful acquisition in the struggle for existence. Therefore, it is widely distributed in nature and is found not only in insects, but also in other living organisms. Metamorphosis allows different stages of the same species to avoid competition among themselves for food and for habitats. After all, the larva eats other food and lives in a different place, there is no competition between larvae and adults. Caterpillars gnaw on leaves, adult butterflies quietly feed on flowers - and no one interferes with anyone. With the help of metamorphosis, the same species simultaneously occupies several ecological niches (feeding both on leaves and flowers in the case of butterflies), which also increases the chances of a species to survive in a constantly changing environment. After the next change, at least one of the stages will survive, which means it will survive, the whole species will continue to exist.

Butterfly development: four stages of the life cycle

So, butterflies are insects with complete transformation - they have all four stages of the corresponding life cycle: egg, pupa, larva caterpillar and imago - an adult insect. Let us consider successively the stages of transformations in butterflies.

Egg

First, an adult butterfly lays an egg and thereby gives rise to a new life. Eggs, depending on the species, can be round, oval, cylindrical, conical, flattened, and even bottle-like. Eggs differ not only in shape, but also in color (usually they are white with a green tint, but other colors are not so rare - brown, red, blue, etc.). Eggs are covered with a dense hard shell - chorion. The embryo under the chorion is supplied with a supply of nutrients, very similar to the well-known egg yolk. It is according to it that the two main life forms of Lepidoptera eggs are distinguished. The eggs of the first group are poor in yolk. In those species of butterflies that lay such eggs, inactive and weak caterpillars develop. Outwardly, they look like tadpoles - a huge head and a thin thin body. Caterpillars of these species should begin to feed immediately after hatching, only after that they acquire quite well-fed proportions. That is why butterflies of these species lay their eggs on a host plant - on leaves, stems or branches. Eggs placed on plants are characteristic of diurnal butterflies, hawks, and many scoops (especially arrowheads).

Butterfly eggs

In other butterflies, the eggs are rich in yolk and ensure the development of strong and active caterpillars. Leaving the egg shell, these caterpillars immediately begin to spread and are able to cover sometimes very considerable distances for them before they find suitable food. Therefore, butterflies that lay such eggs do not have to worry much about their placement - they lay them where they have to. Thinworms, for example, scatter eggs on the ground in bulk right on the fly. In addition to fine-weavers, this method is typical for bagworms, glass-cases, many volnyanka, cocoon-worms and she-bears.

There are also Lepidoptera that try to sink their eggs into the ground (some scoops).

The number of eggs in a clutch also depends on the species and sometimes reaches 1000 or more, but not all of them survive to the adult stage - it depends on factors such as temperature and humidity. In addition, butterfly eggs have no enemies from the world of insects.

The average duration of the egg stage is 8-15 days, but in some species the eggs hibernate and this stage lasts for months.

Caterpillar

A caterpillar is a butterfly larva. It is usually worm-like and has a gnawing mouthpart. As soon as the caterpillar is born, it begins to feed intensively. Most larvae feed on leaves, flowers and fruits of plants. Some species feed on wax and horny substances. There are also larvae - predators, their diet includes sedentary aphids, mealybugs, etc. In the process of growth, the caterpillar molts several times - it changes its outer shell. On average, there are 4-5 molts, but there are also species that molt up to 40 times. After the last molt, it turns into a chrysalis. Butterfly caterpillars living in colder climates often do not have time to complete their life cycle in one summer and fall into winter diapause.

Butterfly caterpillar “Swallowtail”

Many people think that the more beautiful and brighter the caterpillar, the more beautiful the butterfly that has developed from it will be. However, it is often just the opposite. For example, from the bright caterpillar of a large harpy (Cerura vinula), a very modestly colored moth is obtained.

chrysalis

The pupae do not move and do not feed, they only lie (hang) and wait, spending the reserves accumulated by the caterpillar. Outwardly, it seems that nothing is happening, but this last stage of an amazing transformation can be called a “stormy calm”. Inside the pupa at this time, very important vital processes of restructuring the body are boiling, new organs appear and form.

The chrysalis is completely defenseless, the only thing that allows it to survive is its relative invisibility to enemies - birds and predatory insects.

Butterfly chrysalis “Peacock eye”

Usually, the development of a butterfly in a chrysalis lasts 2-3 weeks, however, in some species, the chrysalis is a stage that falls into winter diapause.

Pupae are silent creatures, but there are exceptions: the pupa of the hawk moth dead head and the pupa of the blueberry artaxerxes can ... squeak.

Imago

An adult insect emerges from the pupa - imago. The shell of the pupa bursts, and the imago, clinging to the edge of the shell with its feet, while applying a lot of effort, crawls out.

A newborn butterfly cannot fly yet - its wings are small, as if folded, and wet. The insect necessarily climbs to a vertical elevation, where it remains until it fully spreads its wings. In 2-3 hours, the wings lose their elasticity, harden and acquire their final color. Now you can make the first flight.

The lifespan of an adult varies from a few hours to several months, but the average age of a butterfly is 2-3 weeks.

In contact with

According to most people, a butterfly is one of the most beautiful insects in the world. The history of these Lepidoptera insects begins in the distant Jurassic period and to this day, approximately 157 thousand species can be counted in the order of butterflies. And surprisingly, representatives of this order of insects live, except for Antarctica, in all corners of the globe. Butterflies are amazing and unique insects, the diversity of groups is amazing and delightful. But most of all it is interesting to watch how a butterfly is born.

The life cycle of butterflies can be divided into 4 stages: egg, caterpillar, chrysalis, butterfly. A caterpillar emerges from the egg, which is by nature very voracious, because it needs to gain as many nutrients as possible for the next three cycles. As soon as she leaves the egg, she eats its shell and immediately starts eating the leaf on which the egg was attached.

Throughout its cycle, the caterpillar does what it eats, which is why it grows quickly. In the process of its growth, the caterpillar sheds its skin several times, that is, it molts. Some types of caterpillars increase their weight several thousand times and molt 4-5 times during their life cycle. After the last molt, the caterpillar pupates (turns into a chrysalis). Attached by a silk thread (exuded from the abdomen) to the plant, the caterpillar, hooked on it with its hind legs, hangs in the air. Pupation takes place.

Metamorphosis (complete transformation) occurs at the entire stage of the life cycle of the pupa. From the gluttonous caterpillar, which cared only about food, a producer of offspring will appear - a butterfly. But the chrysalis itself is vulnerable, since it cannot crawl away from danger or fly away. That is why nature has taken care of disguising the pupae, some species cannot be distinguished from twigs or leaves, and many subspecies weave cocoons from many kilometers of silk thread, in which the caterpillars turn into pupae. The life cycle of the pupa depends on the type of butterfly, for some it lasts only a few days, and sometimes up to three years.

When metamorphosis ends, the pupal shell bursts and a butterfly emerges from it. The wings are at first soft and lifeless, as if drooping, so it is very important for a butterfly to find a support, a twig, or a stalk on which it will be convenient for it to gain a foothold and spread its wings. The butterfly begins to flutter its wings, as it needs to dry them.