Butterfly Cycle

Butterflies are beautiful. In fact, there are pavilions built specifically to watch and marvel in the beauty of these creatures. It is difficult to look at a butterfly and picture it as a caterpillar. Yes, those lovely creatures were once caterpillars. The question is, how does this transformation happen? How does an organism transform from being a caterpillar to an insect that feeds through a straw? This article will help shed light and answer all the questions you have about the butterfly life cycle.

Overview of the Butterfly Life Cycle

The butterfly undergoes four stages of development in its lifetime, namely the egg, then the larvae or caterpillar, followed by the pupal or chrysalide stage, and finally the imago or in layman terms, the adult butterfly. This cycle takes approximately one month. The four stage life cycle is known as a complete metamorphosis , a term which means that the adult form of the butterfly is very different from the juvenile form in terms of features and even feeding habits. From what you know and have already witnessed, the caterpillar is very different from the adult butterfly. It is actually difficult to believe that they are one and the same. We are going to examine the development of the butterfly from stage to stage in order to fully understand it.

Eggs to Caterpillar

Adult female butterflies lay a multitude of eggs in order to increase the chance of survival for their offspring. The eggs are strategically laid. This means that a butterfly will only lay eggs on a plant that it feeds on. As an example, the Monarch butterfly only lays eggs on a milkweed plant. We will tell you more about why in a moment. The butterfly also ensures that it lays the eggs in a protective location, away from predators and curious little children who will take the eggs away. For this reason, eggs are mostly laid under leaves. They stick to the plant using a fast drying glue that the butterfly secrets along with the eggs.

Butterfly eggs differ in shape and color, depending on the species of the butterfly. For instance, the Orange Tip butterfly egg is greenish-white when first laid but it turns to orange in a few days, the Large White butterfly has a yellow egg, and so forth. The eggs are either spherical, oval, or pod-shaped. and again, this depends on the butterfly species.

Eggs have a tough shell which is also quite thin, to a point that you can actually see a caterpillar forming through the walls of the shell. At the top of each egg is a tiny hole that is known as the micropyle. It shows the exact place where the sperm penetrated the egg. This hole also serves as the entry point for oxygen and water when the egg is developing into a caterpillar. The egg yolk acts as a source of nourishment for the caterpillar.

After 5 to 10 days after the egg is laid, it is time to hatch. The caterpillar gnaws on the egg shell using its jaws, and as soon as it is out of the egg, it does the most interesting thing. The caterpillar eats the whole egg as its first meal and then it proceeds to feed on the host plant as its main source of nourishment.

Caterpillar to Chrysalis

The caterpillar is scientifically known as a larva. It is always hungry. This is s because feeding is its main purpose for existing in the first place. Before we proceed to the appetite, though, it is important to note that while the caterpillar is developing in the egg, it grows an imaginal disc for each of its adult body parts, namely the eyes, wings, all of them.

Caterpillars live mostly on the underside of the leaves of the host plants in order to avoid predators. In some species, the caterpillars live on the grass during the day and feed at night. This is their survival mechanism. In order to survive, caterpillars have several adaptations too. The hairy caterpillars contain some sharp bristles on the skin. These bristles pierce the predators, causing irritation. Other species survive through camouflage, where their color matches that of the host plant or their appearance resembles that of the predator. For instance, some butterflies have wings that resemble eyes. This scares away predators. Another survival mechanism is the feeding of poisonous toxins to scare away predators. The Monarch caterpillar feeds on the milkweed, which contains poisonous toxins. This protects the caterpillar from predators and even after the caterpillar has become a butterfly, it is still poisonous, even if it is the most beautiful butterfly in the world.

As we said, caterpillars have one purpose: feeding. From the moment they hatch, they immediately start feeding, first on the egg and then on the host plant, proceeding to feed on almost all leaves or tender shoots of the plant. They have very strong mandibles suited for cutting and chewing. Actually, this is the major reason why caterpillars are the most common pests. They love feeding non-stop. This is because they need to grow fat, and fast. They grow by molting, which means the shedding of their outgrown skin. It sheds because it is incapable of stretching. Due to the level of feeding of the caterpillars, they molt more than once.

One day, the caterpillar just stops feeding. This is after continuous feeding for 10 to 14 days when it has finally reached its full length and size. The caterpillar hangs upside down from a twig or a leaf, and, depending on the species, it does either of the following. The caterpillar can spin itself a silky cocoon called a chrysalis, or it can molt one last time into a shiny chrysalis. Either way, they both become a chrysalis.

Chrysalis to Butterfly

When you look inside the chrysalis, your first thought will be that the caterpillar is resting since you do not observe any changes at this point. But this is not the case. The inside of that cocoon is a factory where changes are rapidly occurring because in 10 days, a butterfly should emerge from that cocoon. This is the most intense stage of change in the butterfly life cycle.

The change from caterpillar to butterfly is exactly what happens when a caterpillar spins that silk or molts into a chrysalis. The chrysalis is mostly brown in color. Inside the cocoon, the caterpillar digests itself, releasing an enzyme that dissolves all of its tissues to form a protein-rich soup. The imaginal discs that I mentioned earlier, the breathing tubes, and the nervous system are the only parts that are not digested. Did you know that due to the butterfly maintaining its nervous system, it can actually remember being a caterpillar? Well, now you know.

Imaginal discs are a highly organized group of cells that forms the parts of the butterfly. These discs utilize the protein-rich soup in the chrysalis to rapidly multiply through cell division, forming the body parts of the butterfly. The cell division is rapid and intense, where 50 cells rapidly divide to 50,000 cells in a very short period of time.

After 10 days, a butterfly emerges from the chrysalis. Its wings are very soft and folded against its body, due to the tight space inside the chrysalis. After a period of a couple of hours, the butterfly supplies blood to the wings, which become strong, allowing the butterfly to fly free.

When you come across a chrysalis or cocoon, please do not touch it. This might disrupt the transformation process, leading to the death of the chrysalis. These insects are delicate in all stages of the butterfly life cycle, but especially in their chrysalis forms.

The Adult Butterfly and Reproduction

Within three to four hours post-emergence, the butterfly has already learned how to fly. The only purpose of the adult butterfly is reproduction, just as the main one for the caterpillar is feeding. Immediately after the butterfly flies free, it begins its quest to find a mate in order to reproduce and lay eggs in its short life span, which is around 14 days. Once it finds a mate, the butterfly constantly lays eggs in order to have thousands of them, to increase survival rates.

The adult butterfly feeds on liquid food compared to the caterpillar that eats solid food. Nectar and water are the major food sources of most butterflies. However, in homes where there are butterfly kits and the butterflies are kept indoors to complete their life cycle, you can make a sugar solution for the butterflies. Slices of freshly cut melons, oranges, and bananas are also a source of food for them. In order to feed, the butterfly uses its sensitive antennae to search the air for wind and nectar. The antennae also aid in determining various scents in different flowers. It then feeds with a straw-like structure known as a proboscis . The butterfly unfolds the proboscis when it is time to feed and uses it to suck or siphon its liquid food. After feeding, the butterfly folds it back underneath its head, where the proboscis is located.

When it comes to laying eggs, the butterfly has to choose a plant known as a host plant. This is a plant that a caterpillar can feed on after its emergence from the egg. Different species of butterflies lay their eggs on different host plants. The eggs have to be laid in a place away from prying eyes and predators, preferably under a leaf. In order to locate a host plant, the butterfly has to taste different types of plants. The amazing fact is that the butterfly uses its feet to taste. The feet are known as tarsi, and, upon landing on a plant, the butterfly can know if it is the host plant or not. After finding the host plant, the butterfly lays hundreds of eggs that form the next generation of butterflies.

Butterflies can survive the winter. Mostly, they survive this cold season as a larvae or chrysalis, but a few species survive winter in their mature stage. The Monarch butterfly however, cannot survive cold weather. The species therefore migrates, like birds and wildebeests. You may be wondering how they pull off migration when their adult lifespan is only two weeks. The Monarch butterfly has a “super fourth generation” of butterflies that live up to 8 or 9 months. It has not yet been established how this is possible. They migrate to escape the winter, using the sun as a compass. They can navigate for a total distance of 3,000 miles, to and fro, without losing their way. After the winter, the descendants of the migrant butterflies return to their original habitat to lay more eggs and complete their life cycle in their ancestors’ home area.

Supporting the Butterfly Life Cycle

Every stage of the butterfly life cycle is important. It is therefore crucial that the eggs be protected through suppressing the urge of wiping them off a leaf in your garden. This allows them to hatch, and hopefully complete their entire life cycle. Butterflies are a symbol of life and a clean environment. Their magnificent wings are particularly very interesting to watch as the butterflies fly around in the garden, making the environment beautiful.

Their role in pollination is also an important reason to let the butterflies live. They play a major role in ensuring that plants reproduce, and, in some scenarios, the transfer of pollen leads to variation, creating new varieties of plants.

You can read more about the butterfly life cycle in National Geographic’s special issue , complete with photos and illustrations.