The Life Cycle of Butterflies and Moths

Life Cycle of Butterflies and Moths

Michele Westmorland / The Image Bank / Getty Images

  • B.A., Political Science, Rutgers University

All members of the order Lepidoptera, the butterflies and moths, progress through a four-stage life cycle, or complete metamorphosis. Each stage—egg, larva, pupa, and adult—serves a purpose in the insect’s development and life.

Egg (Embryonic Stage)

Once she has mated with a male of the same species, a female butterfly or moth will deposit her fertilized eggs, usually on plants that will serve as food for her offspring. This marks the beginning of the life cycle.

Some, like the monarch butterfly, deposit eggs singly, scattering their progeny among the host plants. Others, such as the eastern tent caterpillar, lay their eggs in groups or clusters, so the offspring remain together for at least the early part of their lives.

The length of time required for the egg to hatch is dependent on the species, as well as environmental factors. Some species lay winter-hardy eggs in the fall, which hatch the following spring or summer.

Larva (Larval Stage)

Once development within the egg is completed, a larva hatches from the egg. In butterflies and moths, we also call the larvae (plural of larva) by another name—caterpillars. In most cases, the first meal the caterpillar eats will be its own eggshell, from which it gains essential nutrients. From then on, the caterpillar feeds on its host plant.

The newly hatched larva is said to be in its first instar. Once it grows too big for its cuticle, it must shed or molt. The caterpillar may take a break from eating as it prepares to molt. Once it does, it has reached its second instar. Often, it will consume its old cuticle, recycling the protein and other nutrients back into its body.

Some caterpillars look just the same, only bigger, each time they reach a new instar. In other species, the change in appearance is dramatic, and the caterpillar may seem to be an entirely different kind. The larva continues this cycle—eat, poop, molt, eat, poop, molt—until the caterpillar reaches its final instar and prepares to pupate.

Caterpillars readying for pupation often wander from their host plants, in search of a safe place for the next stage of their lives. Once a suitable site is found, the caterpillar forms a pupal skin, which is thick and strong, and sheds its final larval cuticle.

Pupa (Pupal Stage)

During the pupal stage, the most dramatic transformation occurs. Traditionally, this stage has been referred to as a resting stage, but the insect is far from at rest, in truth. The pupa does not feed during this time, nor can it move, though a gentle touch from a finger may yield an occasional wiggle from some species. Butterflies in this stage are chrysalides and moths in this stage are cocoons.

Within the pupal case, most of the caterpillar body breaks down through a process called histolysis. Special groups of transformative cells, which remained hidden and inert during the larval stage, now become the directors of the body’s reconstruction. These cell groups, called histoblasts, initiate biochemical processes which transform the deconstructed caterpillar into a viable butterfly or moth. This process is called histogenesis, from the Latin words histo, meaning tissue, and genesis, meaning origin or beginning.

Once the metamorphosis within the pupal case is completed, the butterfly or moth may remain at rest until the appropriate trigger signals the time to emerge. Changes in light or temperature, chemical signals, or even hormonal triggers may initiate the adult’s emergence from the chrysalis or cocoon.

Adult (Imaginal Stage)

The adult, also called the imago, emerges from its pupal cuticle with a swollen abdomen and shriveled wings. For the first few hours of its adult life, the butterfly or moth will pump hemolymph into the veins in its wings to expand them. The waste products of metamorphosis, a reddish liquid called meconium, will be discharged from the anus.

Once its wings are fully dried and expanded, the adult butterfly or moth can fly in search of a mate. Mated females lay their fertilized eggs on appropriate host plants, beginning the life cycle anew.

www.thoughtco.com

Galatea butterfly: photo, lifestyle and stages of development of the palearctic species

show/hide words to know

Life Cycle: the sequence of all stages through which an organism passes — going from egg to adult.

Migration: movement of an animal or a group of animals from one place to another.

The Monarch Butterfly Life Cycle

There are four stages in the life cycle of a butterfly. The stages include, egg, larva, pupa, and adult. The entire process is called complete metamorphosis and is one of two ways insects develop from an egg to an adult. The other type of insect development is called incomplete metamorphosis.

Egg

A monarch begins life as a single cream-colored egg attached to the underside of a milkweed leaf.

Illustration of a monarch butterfly egg. Notice this egg surface is not like a chicken or bird egg.

The worm-like larva grows inside the egg. When it is ready, the larva chews a small hole in the egg shell and wriggles its way into the world. After a few minutes, the newly hatched larva has its first meal — the remains of its egg. Female monarchs lay one to three eggs on the underside of milkweed leaves. This process is repeated until the female has laid hundreds of eggs. |top|

Larva

After eating the shell, the larva begins to eat milkweed leaves. Milkweed is the only plant that monarch larvae will eat. The larva eats and grows, grows and eats. The larva grows so much that it outgrows its skin, much like outgrowing old clothes.

In order for the larva to keep growing, molting must occur. The old skin splits, revealing the new skin underneath. The larva wriggles free of the too-tight skin. After freeing itself, the molted larva often eats its old skin before moving on to more milkweed leaves. |top|

After shedding their skins, monarch larvae continue to grow and will have to molt four more times. The last molt is much different than the others. The larva crawls away from its milkweed plant, searching for a suitable place. Some larvae will travel longer distances than others. When the larva has found a suitable place, it weaves a silk mat with a «button» in the center. Once the mat and button are ready, the larva grabs the silk with its legs and hangs upside down. The front part of its body will curve to make a «J-shape.» |top|

Once in the «J», the larva molts for the last time. The skin splits behind the head, and the larva wiggles while it hangs upside down to remove the old skin. This final molt is the trickiest, because the larva must shed its old skin and still hang onto the silk button. Once the larva embeds a hook-like structure at its rear end into the button, the rest of the skin can slip off. |top|

See also:  How Does Too Much Sugar Affect Your Body?

Pupa

When the skin fall off, the larva becomes a pupa. The monarch has no eyes and no antennae. It has no legs, and it cannot move. All of the major changes in body shape, size, and arrangement happen. In monarchs, this stage can last as long as a week. At the end of this stage, an A Monarch butterfly (Danaus plexippus) emerging from a chrysalis. It took about 15 minutes for the Monarch’s wings to fully expand. Image by Megan McCarty – via Wikimedia Commons.

Adult

A newly emerged butterfly will wait two or more hours before it can fly. New wings are small and shriveled, so the butterfly pumps body fluid through its wing veins in order to make them get bigger. Then, the monarch has to wait for air to replace some of the fluid. Until this happens, the monarch cannot fly, and its wings are easily damaged. |top|

After the wings have hardened, the butterfly flies away to find its first meal. From this point on, the monarch drinks all of its food. The butterfly will visit several different kinds of flowers to get its nectar dinner. |top|

A monarch butterfly caterpillar eating a Swan plant leaf. Image by Pseudopanax via Wikimedia Commons.

Food

Part of the life cycle of the butterfly is their change in diet during different stages of development. Monarch larvae only eat the leaves of the milkweed plants. Once they become an adult they switch to feeding on the nectar of different plants including milkweed.

Not only do adult monarchs need to drink nectar, but like other butterflies they also need to drink water. You can sometimes see them on damp ground where they can get water from the soil. This is called mud-puddling, or puddling.

Mating

A monarch butterfly uses its long proboscis to drink nectar from a flower. Image by CJ Kazilek.

Adult monarchs begin mating in the spring, before they return to their summer range. Female monarchs will generally lay one to as many as three eggs on the underside of milkweed leaves. She does this many times until she has laid hundreds of eggs. These eggs will hatch into larva, pupate, and become adults in the summer. These new adults will also mate. The new females will lay eggs as they fly northward. This cycle repeats throughout the summer.

Finally, in September, mating stops. The last generation of the summer is the one that will migrate to the overwintering grounds.

askabiologist.asu.edu

Cockchafer insect. Description, species, lifestyle and habitat of the chafer

Description and Features

Since ancient times, the people of these bugs have been called Khrushchev. At times there were so many of them that they fell in abundance directly to the ground and fell under the feet of passers-by. People stepped on them, while there was a loud crunch.

There is another version about the reasons for this nickname: supposedly these creatures are so voracious that they themselves crunch, eating young foliage with appetite, although few have heard this with their own ears.

Later, scientists, separating these biological organisms into a special subfamily from a more general group — the family of lamellae, gave them the same name: Khrushchev. They were classified as arthropods, because beetle feet in their device are fully consistent with this name.

These creatures brought a lot of damage to humans. Hordes of such prolific vandals can do more damage to farmland than the invasion of enemy armies. It is estimated that the only larva of a gluttonous chafer has such an immense appetite that it is able to gnaw all the roots of a young tree, literally destroying it in one day only.

Such pests eagerly eat important parts of plants: leaves, flowers, fruits, even needles, in a short time exposing branches and trunks. That is why the appearance of these creatures in the infield becomes a terrible threat to the existing green spaces and a real tragedy for the owners who are ready for a desperate war with unbearable «invaders».

But both sides suffer in such a battle, because people brutally take revenge on unpleasant «aggressors» for the problems, without pity poisoning them with pesticides and other killer substances. For example, it is known that as far back as the 19th century, almost 30 thousand centners of these pests were destroyed in Saxony, which, according to conservative estimates, is 15 million copies of gherkins.

And this is not the most stunning of the facts, because in the next century the poisons became more perfect, and there were more victims. And only recently, in connection with the prohibitions on a number of harmful substances, mass persecution slowed down somewhat.

As a result of this war of a person with a gluttonous insect, the number of the latter on Earth at one time decreased catastrophically. However, even despite the fact that the biped and the indicated pests are closely on the same planet, it is impossible not to notice that Chafer — This is a unique creation, incomprehensible to the human mind.

For example, it is known that such creatures belonging to the order of beetles can fly. But scientists, studying this process in detail, just make a helpless gesture, claiming that such movement through the air contradicts all existing laws of aerodynamics, and therefore simply impossible. And this is not the whole list of unique features and mysteries of these creatures.

Khrushchev is voracious, but otherwise harmless and harmless to humans. Many of us remember and love these insects from childhood. They appear every year in May and from these spring days, when birches are actively overgrown with warts — resinous glands, and oaks bloom their leaves, begin their active, including nutritious, activity. That’s why bugs are called May beetles.

It’s easy to observe their life and behavior, it’s only worth going to the countryside. Khrushchev not only harms, but also makes a positive contribution to the ecosystem, turning into an ideal complete protein feed for many birds, hedgehogs, reptiles and other living creatures.

This is the most important Maybug functions in the cycles of nature, because it not only absorbs, but also becomes food itself. These are the laws of nature. These organisms, as biological material, turn out to be useful even to humans, coming in handy as bait for large fish, which is a great pleasure for fishermen. By the way, Khrushchev successfully used in alternative medicine. They treat scrofula, uterine cancer, sciatica and many other ailments.

Khrushchev is not at all a small insect, in some cases capable of reaching sizes up to three or more centimeters. It has an oval, elongated convex body, which can be brown with a reddish tint or black.

The most arbitrary color variations are also possible. Maybug body built of three main parts: the head, chest, as well as the large size of the abdomen in comparison with them. This insect is protected by excellent armor — chitinous shell.

In form, it is semi-oval, in some cases covered with a dotted pattern, and sometimes with scales. In structure, it is glossy, smooth, fragile. The back of the beetle is called pygidium. It is especially developed in males and can be sheer or sloping, obtuse or triangular, depending on the variety.

See also:  Read Download Cockroaches PDF – PDF Download

Structure

If a person could be reduced to the size of a bug or if, as if by magic, it would increase its proportions, then the two-legged would be amazed at what fantastic monsters live on their own planet.

Not only is Khrushchev an armored walking tank, it is also an extremely hairy creature. The indicated vegetation is a kind of hairy scales of very different lengths and colors: yellow, grayish, white.

As for the quantity, in some specimens of beetles the shoots are so dense that the main body color is completely impossible to consider behind it. Similar hairs are located on the head in the form of longitudinal shriveled stripes.

Single protruding, elongated vegetation is on elytra. The insect’s chest is also strewn with yellowish long scaly processes. Different shapes, lengths and colors of hairs are found on other parts of his body.

The external structure of the May beetle bizarre and peculiar. But let’s start with the head. This is a very small part of the body almost square in shape, pulled into the elytra, most often dark, sometimes greenish. Convex organs of vision are located on both sides of it, allowing you to view surrounding objects at a significant angle.

The eyes of Khrushchev have a very complicated structure and consist of a huge number of small eyes, the number of which reaches several thousand. A pair of antennae, similar to antennas, consisting of ten segments and fan-shaped at the ends, is attached to the front of the head.

An important part of the gluttonous grub is the oral apparatus, also located on the head. On top of it is the upper lip in the form of a small plate. The most prominent area of ​​it are mandibles, which serve to successfully absorb and grind food.

They are actually the upper jaw, and the lower has tactile palps with receptors. These are the first two pairs of oral formations. The third is the lower lip with similar organs of touch. In general, palps exist to promote food, and such creatures actively use their jaws to eat it.

The chest is built from three areas. Its lower part is important because the legs are attached to it. There are six of them and each pair of them departs from one of the parts. The limbs consist of segments and end with claws with a sharp tooth.

The upper zone is called the prothorax. Hard elytra adjoin it. They protect the more delicate parts from the back and most importantly — the hind wings of the insect, which have a brownish-yellowish, or brownish-red hue. The belly of the beetle contains many important organs for life and is built of eight segments.

Atmospheric oxygen enters the body of the insect through the spiracles — small holes. In total there are 18 pieces. They are located not only on the abdomen, but also on the chest of such creatures. Air passes through them at the may bug in trachea.

This is a kind of breathing tube. It is as if they envelop all the organs with themselves, and therefore the life-giving air freely spreads into each zone of the body. Khrushchev has no lungs. And therefore, like some other terrestrial organisms that do not have them, he carries out breathing in a similar way.

Beetles have blood. However, its circulation system is underdeveloped and open. She is involved in the transfer of nutrients, but not in respiration. In supplying all parts of the body with life-saving oxygen, it consists chafer beetle function.

Food absorbed by a gluttonous insect enters through the mouth into the esophagus, then into the stomach, and its remnants enter the environment through the anus.

The brain of a beetle is only an accumulation of nerve cells in a small head. Therefore, attributing it to the number of intellectual insects, such as, for example, bees, is in no way possible.

Kinds

Regarding how many types of gherkins are on the list of inhabitants of the planet, there are the most conflicting data. Just structure of may bugs, as well as their size and color parameters are diverse. And it is not clear whether to attribute them to intraspecific individual traits or to consider them as features of whole groups.

In addition, the insect world is so rich that data about them is updated. Mutations are constantly occurring, new species are being identified, and some of the types of beetles disappear from the face of the planet or are simply considered extinct due to a rarity. Therefore, some people count up to hundreds of species in the subfamily of khrushchev. Although other data is much more modest.

Consider some of the examples described by scientists found in Eurasia.

1. Western Khrushchev — a fairly long representative of its subfamily, growing on average to almost 3 cm. The back of the beetle tapers towards the end smoothly and gradually, and not sharply, as in many species. Such insects, in comparison with their counterparts, are thermophilic, and therefore begin their vital activity in the spring later than others.

Their body is predominantly black in color, with the exception of the elytra. They can also be dark, but also brown with a reddish tint or brown, although there are very different color variations.

Such beetles live in Europe. And more specifically, in accordance with the name, mainly spread throughout its western part. In Russia, they usually do not occur further than Smolensk and Kharkov, if we move eastward.

2. Eastern Khrushchev — slightly smaller than the previous variety in size. Adult beetles usually have a little more than 2 cm in length. Such creatures are famous for the variability of color schemes, however, brown-red is considered the predominant shade.

The thickened back of the torso, as well as the legs and antennae, are painted black. The head is dotted with clearly visible yellowish hairs and dotted dots. Such creatures are found in the center and in the north of Europe. Further, their range extends east to Siberia and the Asian regions to Beijing. In the south, the habitats of such bugs reach Altai.

3. March Khrushchev. His body, in comparison with relatives, is not long, but wide, has a black color with the addition of a brilliant tint. The back is blunt. The front area is covered with thick hairs.

Elytra brown with yellowness and dark side. Such bugs live in the eastern regions of Uzbekistan. And thanks to the mild climate of those parts, they begin seasonal activities in the early spring, therefore they are called March.

4. Transcaucasian Khrushchev appears stocky, with a convex and very wide body. The average length of such creatures is 2.5 cm. The head and lower regions are black, the elytra is brown with the addition of brown, red, black or whitish hues. Such bugs are found in the Caucasus and southern Europe.

Often, along with May man, in nature, brilliant green bugs are found. They are called colloquially bronzes. At first glance, these insects are similar, although their biology is different.

See also:  Termite Infestation Probability Map For The USA, Australia - The World

Bronze bronzes, like khrushchs, are harmless to humans, so picking them up is not at all dangerous. But they are not so voracious, although they like to feast on the pulp of fruits and flowers, and therefore do not fall into the list of malicious pests.

Lifestyle & Habitat

In the photo of the May beetle You can examine in more detail the appearance of this inhabitant of the planet. Most varieties from the subfamily of Khrushchev have chosen the lands of the Palearctic. It is in the zone of this biogeographic region that the overwhelming majority of groups of such insects live.

Eurasia is especially rich in their diversity, but its part is not always eternally cold; there the beetles did not take root there. Some of the species, although they are much smaller, inhabit Africa and even South America, but are mainly found only in the Northern Hemisphere.

For the successful existence of insects in the area, the proximity of reservoirs, as well as sandy loose soil are necessary. It is important not only for bugs, but also for plants growing on it, as a guarantee of abundance of feed.

In addition, if the soils are clay, they impede the successful distribution and May bug developmentsince it is unsuitable for digging tunnels in which the raspberries tend to lay their eggs. That is why these creatures most remarkable take root in the river valleys.

In the spring, males appear first of their grunts. And only after a week and a half, their friends join their gentlemen in order to begin the usual summer life for such bugs. The stages of development of such biological organisms are such that they are able to fly for the entire time of their existence for no more than forty days.

But if they mature, they try to make full use of their natural capabilities. During air travel, they accelerate to 10 km / h and accompany their flights with a noisy buzz. In their quest to find sources of food, beetles can overcome up to two tens of kilometers in a day.

These creatures are rare stubborn. And if they have set a goal for themselves, it’s difficult for outsiders to push them off course. Even if a joker catches a stubborn traveler and firmly tries to disorient him, being on the outside, the beetle will still fly with enviable persistence in the same direction.

But if the Khrushchev managed to find food, then they strive to work more actively with their jaws. And next to the objects they love, it’s easy to find gnawed scraps of leaves and numerous excrement in abundance. They can eat in the daytime and after midnight.

When the supply of quality food runs out, the beetles again set off in search of food adventures. Their activity, depending on the species, can occur in the predawn hours or evening twilight. May beetle It can also fly, and when it sees burning lanterns or bulbs, it hurries quickly to the light source.

Enough has already been said about the appetite of these insects, as well as about what attracts the krashchik exclusively to the vegetable menu. It’s time to talk about taste preferences.

May bugs can be considered gourmets, because they especially like to feast on fresh shoots and young herbs. As a result, wild plants and crops are affected. Of the latter, especially favorite are: apple tree, plum, cherry, cherry.

However, since khrushchev is practically omnivorous in terms of plant diet, all values ​​of a gardener may suffer from their gluttony: currants, gooseberries, sea buckthorn and others.

Of the forest trees in danger are: birch, oak, aspen, poplar and others, others, others, as well as more rare: hazel, chestnut and others. More specifically, feed preferences to a large extent depend on the type of beetle, as well as on its habitat and the representatives of the flora that grow there.

Khrushchev destroy various parts of plants: ovaries, flowers, leaves, roots. Whether it is woody food, shrubbery or grass is largely determined by the stage of development of these gluttonous creatures.

For instance, beetle larva, which begins its life in the soil, in the first year of its existence does not have a great destructive power. She eats rhizomes of herbs and humus.

But after a year already eats the roots of forest trees, berry and fruit crops. In the same way, significant damage is caused to strawberries, potatoes, carrots and others. Adult beetles that exist in the above-ground world prefer the upper parts of shrubs and woody flora. How it all ends is already known.

Reproduction and longevity

If a human cub, coming into this world, although it does not externally copy adults, but still resembles representatives of the human species in proportions and body parts, then this is not so for insects.

Khrushchev, for example, appearing in nature from grayish-white eggs similar to beads, are not at all what they become in the end. And only in the process of passing certain stages of transformations mature beetle organs and an adult is born in the already described form.

And it all starts like this. Since the end of May, the female has been feeding and mating intensively, digging tunnels in the soil and placing eggs in them. Then it is saturated again and repeats the reproductive cycle, making it three, or even four times a season, after which it dies. The total number of eggs that she manages to lay reaches 70 pieces.

After a month or more later, larvae, also called grooves, hatch from the underground masonry. It looks like an unpleasant elongated “something”, similar to white caterpillars with sparse hairs, curved and thick, having three pairs of legs and powerful jaws. Such creatures will spend about three, and sometimes four, years in the underworld.

In winter, the furrow, digging the soil, goes deeper into the earth, and rises higher by spring, so that it is saturated with plant roots all summer. In search of food, the larva is able to move within a day to the distance of a human step and grows over time to five centimeters or more. Further, by the end of the third summer, it turns into a chrysalis, resembling in this state a beetle immured in a bizarre cell.

Until the next spring, this creature remains underground, undergoing a series of transformations and gradually freeing itself from its doll swaddles. And in April or May of the next season, the formed individual (imago) makes its way out to a new life.

Caught in the above-ground world, driven by hunger, at first she was only concerned with the search for food and intensely sought to get enough of young shoots, buds, leaves. In the adult stage, the bug will last about a year, until death. And the full life cycle of the khrushch is no more than five years.

lr.highriverlabs.com

Share:
No comments

Добавить комментарий

Your e-mail will not be published. All fields are required.

×
Recommend
Adblock
detector