Difference Between Caterpillar and Butterfly in Life Cycle

The largest phylum under the animal kingdom is Arthropods, and the largest class under it is Insecta or Hexapoda. They are characterized by segmented bodies, jointed legs and exoskeletons. Unlike other arthropods, their bodies can be clearly defined into three major regions:

1. Head- With clearly defined mouthparts, eyes, and antennae.

2. Thorax- Segmented into three and has three pairs of legs.

3. Abdomen- Further segmented into many parts containing the digestive, excretory and reproductive organs.

They further include orders like Hymenoptera (ants), Diptera (mosquitoes), Odonata (Dragonfly), Lepidoptera, and so on. The order Lepidoptera further includes moths and butterflies.

Key Differences between Caterpillar and Butterfly

The following are the key differences between caterpillar and butterfly.

• Caterpillar feeds on solid food by biting and chewing type of mouthparts, while the butterfly feeds on liquid food by sucking nectar from the flower by siphoning type of mouthparts.

• Caterpillar has prolegs, whereas the butterfly has no legs.

• Caterpillar has simple antennae, whereas the butterfly has long club-shaped antennae.

• Caterpillars have no wings, whereas butterflies have wings for flying

Caterpillar and Butterfly

The Lepidoptera order in Insecta further has various super-families. Butterflies are insects that come in the Superfamily of Papilionoidea. They come with colorful wings, a slender body, and legs. Their body is covered with dusty scales, meaning the term Lepidopters- scaly wings.

The Lepidopteran life cycle has four stages, which are:

• Egg- It is laid on leaf surfaces and stems by female butterflies. These tiny eggs can vary in colour and be cylindrical or oval. When the conditions are warm and favorable, they hatch into the larval stage, also called the caterpillar.

• Larva (Caterpillar)- They are cylindrical-shaped creatures with segmented bodies and six small eyes. During this stage, the caterpillars are very hungry, and they go around feeding on leaves constantly and moult repeatedly.

• Pupa (chrysalis)- Once the caterpillar is mature; they form a covering or a vessel around themselves. Layers of skin harden this vessel to protect the larva inside. Once the larva has fully developed wings and transformed into the next stage, the vessel breaks and the butterfly breaks out. 

• Imago (Butterfly)- This is the adult stage where the butterfly has fully developed wings. When blood is pumped into the wings, they can fly and search for food and mates. After successfully mating, the female butterflies lay eggs on a leaf surface to continue the next cycle.

The process by which the egg undergoes drastic bodily changes to transform from a larva into a butterfly is called metamorphosis.

Caterpillars are primed to become Butterflies from Birth

Surprisingly, in the smallest caterpillar which are just hatched from the minuscule egg, bundles of cells are already primed, and predetermined to become adult features such as wings, legs, antennae, and genitalia. 

A burst of the moulting hormone, ecdysone, is released when it reaches a critical size. It will lose its skin several times with regard to ecdysone, each time forming a new instar (stage). But the juvenile hormone keeps it a caterpillar and thereby prevents onward development until, as it approaches full size, concentrations of the latter hormone decline.

The primary differences between caterpillar and butterfly are:

Differentiating a Butterfly from Caterpillar

How does a Caterpillar turn into a Butterfly?

These are some of the exciting differences between caterpillars and butterflies.

The transformation of a caterpillar into a butterfly has been an interesting subject for all. The metamorphosis of a crawling, stubby, land-based insect into a fluttering fairy is the perfect metaphor for change, improvement, escape, even life after death.

It has been observed that all caterpillars do not turn into butterflies, some turn into moths instead. All caterpillars go through the same four stages: egg, larva, pupa and adult, whether they destine to become a butterfly or a moth. All four stages have different goals and time lengths. For instance, the monarch butterfly completely forms in about one month. These transformations are also called metamorphoses. It is a greek word, which means “transformation” or “change in shape.”

There are two types of metamorphosis for insects: incomplete and complete. 

• Incomplete Metamorphosis: When the young insect looks like a small version of the adult insect is called incomplete metamorphosis. For example, cockroaches, crickets, dragonflies, grasshoppers, and termites.

• Complete Metamorphosis: When the young insect looks different from the adult insect and must change drastically to look like the adult is called complete metamorphosis. For example, bees, beetles, butterflies, moths, and flies.

Stage 1: Egg

The life of the butterfly starts in a small, round, or oval egg. The shape of the butterflies depends on their type. Most butterflies lay their eggs on leaves, which are attached to the leaves with an adhesive fluid.

Stage 2: Larva

Once the butterfly formulates from the egg, it becomes a larva. This larva stage is actually when the butterfly is in caterpillar form. The tiny caterpillar has antennae, small eyes, and short legs, and has bundles of cells called imaginary discs that are waiting to turn into butterfly features, including long antennae and legs, as well as wings. 

Stage 3: Pupa

During this pupa stage, the caterpillar is now ready for the next stage. Once the caterpillar is done growing, there is a lack of the juvenile hormones, which causes the caterpillar to form a silk cocoon or shiny chrysalis around itself. Then it begins radically transforming into a beautiful butterfly. 

Stage 4: Adult

The final stage ends with a butterfly. The newly formed butterfly breaks free from its cocoon. It takes some time to stretch its long legs and antennae and pump hemolymph (the blood-like substance of insects) into its wings so it can fly. The butterfly waits for the wings to dry and grow to their full size.

Fun Facts

• Queen Alexandra’s birdwing is the largest species of butterfly amongst 20,000 different species. 

• The most massive caterpillar in the world is the Hickory Horned Devil.

• Humans have three types of photoreceptors that allow us to see all these different colours. Butterflies have 15 types of photoreceptors that would enable them to see shades that we will never know of.

• The 'ordinary colours' on the wings of the butterfly comes from the pigment in their body. This pigment melanin is the same as that found in humans. The shiny 'structural colours' on their wings result from the wing structure and its overlapping scales, causing iridescence or the glossy effect. This helps the butterfly in camouflaging and deceiving its predators.