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.

Egg

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.

Caterpillar: The Feeding Stage

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.

Pupa: The Transition Stage

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.

Adult: The Reproductive Stage

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.

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life cycle of frog

The Egg

Frogs lay their eggs in water or wet places.  A floating clump of eggs is called frog spawn.    

The large and slippery mass of eggs are too big to be eaten.  This is nature's way of protecting them.  But, the smaller clumps of eggs will be eaten by the creatures living near or in the pond.

The egg begins as a single cell. Several thousand  are sometimes laid at once. It becomes surrounded by a jellylike covering, which protects the egg. The female may or may not stay with the eggs to take care of the young after she has laid them. The egg slowly develops. But, only a few develop into adults.  Ducks, fish, insects, and other water creatures eat the eggs.

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The Cell Splits

The single cell in the egg eventually splits into two. These two split making four cells, and so on. Eventually, there are many cells in the egg.

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The Embryo

The mass of cells in the egg come to form an embryo. Organs and gills begin to form, and in the meantime, the embryo lives off of its internal yolk. This supplies it with nutrients for 21 days. Then . . .

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The Tadpole

After its 21 day development period, the embryo leaves its jelly shell, and attaches itself to a weed in the water. This quickly becomes a tadpole, a baby frog.   The tadpoles grow until they are big enough to break free into the water.  This can take from 3 days to 3 weeks, depending on what kind of frog they will become.  They eat very small plants that stick to larger plants in the water.  These tiny plants are called algae. The tadpole has a long tail, and lives in the water. It is extremely vulnerable, and must rely on its camouflage to protect it. 

The tadpole has a long tail, and lives in the water. It is extremely vulnerable, and must rely on its camouflage to protect it.  The tadpoles also face danger by being eaten by other water animals.  Sometimes the pond dries up. As a result the tadpoles die.

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The Tadpole Begins To Change

After about five weeks, the tadpole begins to change. It starts to grow hind legs, which are soon followed with forelegs.   Behind their heads bulges appear where their front legs are growing. Their tails become smaller.  Lungs begin to develop, preparing the frog for its life on land.   Now and then, they wiggle to the surface to breathe in air.  The tail becomes larger and makes it now possible for the tadpole to swim around and catch food.  They eat plants and decaying animal matter.  Some tadpoles eat frogs eggs and other tadpoles.

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Almost There . . .

Over time, the tadpole becomes even more froglike.  They have shed their skin and lips. Its mouth widens, and it loses its horny jaws. The tail becomes much smaller, and the legs grow. The lungs are almost functioning at this point.

 

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The Frog

Eleven weeks after the egg was laid, a fully developed frog with lungs, legs, and no tail emerges from the water. This frog will live mostly on land, with occasional swims. The tiny frogs begin to eat insects and worms.  Eventually, it will find a mate. The way this is done varies depending on the species. The female lays the eggs, the male fertilizes them, and the whole process begins again. 

 

 
 

animalia metamorphosis |Insect metamorphosis| Metamorphosis is a biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some insects, amphibians, molluscs, crustaceans, Cnidarians, echinoderms and tunicates undergo metamorphosis, which is usually accompanied by a change of habitat or behavior. Scientific usage of the term is exclusive, and is not applied to general aspects of cell growth, including rapid growth spurts. References to "metamorphosis" in mammals are imprecise and only colloquial, but historically idealist ideas of transformation and monadology, as in Goethe's Metamorphosis of Plants, influenced the development of ideas of evolution.

All insects in the Pterygota undergo a marked change in form, texture and physical appearance or metamorphosis, from immature to adult. These insects either have hemimetabolous development, and undergo an incomplete or partial metamorphosis, or holometabolous development, which undergo a complete metamorphosis, including a pupal or resting stage between the larval and adult forms.[3] Incomplete metamorphosis in the grasshopper with different instar nymphs In hemimetabolous insects, immature stages are called nymphs. Development proceeds in repeated stages of growth and ecdysis (moulting); these stages are called instars. The juvenile forms closely resemble adults, but are smaller and lack adult features such as wings and genitalia. This process is known as "partial" or "incomplete" metamorphosis. The differences between nymphs in different instars are small, often just differences in body proportions and the number of segments, although external wing buds will form in later instars. In holometabolous insects, immature stages are called larvae, and differ markedly from the adults. Insects which undergo holometabolism pass through a larval stage, then enter an inactive state called pupa, or chrysalis, and finally emerge as adults. This process is called "complete" metamorphosis. It is theorized that the pupal stage is the evolutionary compaction of all the nymphal stages of their hemimetabolous ancestors, while the larval stage is an extended, mobile form of the developing embryo[4]. According to recent research, adult Manduca sexta is able to retain the behaviour learned as a caterpillar.[5] Many observations have indicated that programmed cell death plays a considerable role during physiological processes of multicellular organisms, particularly during embryogenesis and metamorphosis.