The caterpillar is a invertebrate animal that belongs to the breeding of a butterfly o a moth. After 2-3 weeks it wraps itself in silk, forming a cocoon called a pupa. In this stage it remains for about 2 weeks. After that time, the caterpillar emerges looking so differently, and with wings. This entire process is known as metamorphosis.

Close-up of a caterpillar
Close-up of a caterpillar


There are more than 20.000 different species of known caterpillars, as it is believed that there are thousands yet to be discovered because new butterflies or moths are still being discovered in regions where not many humans live.


The caterpillar varies in size, color and appearance according to the species to which they belong. The size ranges from 1 mm to 14 cm of some species. Certain caterpillars are brightly colored, while other caterpillars are totally the opposite.

They are soft, hairy and soft. Each caterpillar has a different appearance that seeks to deter predators and prevent them from being eaten. Different markings on a caterpillar can make it appear poisonous, more threatening (because of size), inedible, or camouflage itself by changing color depending on what they eat.

Other species of caterpillars are very toxic, especially those that live in the rainforest. Not all species are permanently toxic, since some are only so during their larval stage and cease to be after they stop being pupae.

Sometimes the larva of the sawfly is confused with a caterpillar but it has certain differences. These larvae lack prolegomena in the abdominal segments, hooks in the prolegomena, a pair of ocelli in the head capsule, and an absence of an inverted "Y" -shaped suture in the front of the head.


Certain caterpillars are shared in a certain way to avoid predators. Aside from their own defenses, as mentioned above, some caterpillars feed in protected environments, such as inside silk stalks, on rolled leaves, or by punching holes between the leaf surfaces. Others have elongated whip-shaped organs attached to the ends of the body that they use to scare away flies and predatory wasps.

Other species associate with ants for protection. They communicate through vibrations or chemical means, to pay for protection, the ants are rewarded with food. The family of butterflies Lycaenidae (lycene) practices this association.

Caterpillar camouflaged behind a leaf
Caterpillar camouflaged behind a leaf

There are also species that create communities that help reduce levels of parasitization and predation. The pine processionary caterpillar (Thaumetopoea pityocampa) It can be seen in large Indian lines (similar to a train) moving through the trees and over the ground.

Many caterpillars are nocturnal. Caterpillars of the family Noctuidae hide under leaves during the day and take heart at night. Other species, such as gypsy mothLymantria dispar) their activity patterns alternate depending on the density and the larval stage, with more diurnal feeding in the early stages and at high densities.


The caterpillar inhabits a wide variety of environments and depending on the species the habitat can change. They can be found in urban, humid areas, forests, deserts, grasslands, and rain forests.


The caterpillar is distributed throughout the world, in any area where there are forest areas.


The caterpillar varies its diet depending on its species, although most species are herbivorous. They feed mainly on leaves, silver and flowers. You can recognize the presence of a caterpillar by looking at the holes in the leaves.

Some caterpillars are carnivorous and eat a wide variety of foods. A kind of Hawaiian caterpillar, it anchors itself to a leaf upright as I wait to capture an insect.


Due to its small size, the caterpillar is the victim of many scrubbers. The main ones are birds, large insects such as wasps, and are sometimes hunted by small mammals and reptiles.


The caterpillar cannot reproduce until it has completed all stages of metamorphosis. If you are interested in knowing how a caterpillar is born you can see the animal file of the mariposa or moth.

State of conservation

As the caterpillar is not a species in itself, and there may be more than 20.000, a conservation status cannot be specified, but most of them are not in danger.

Relationship with humans

The caterpillar is considered a pest in most species as it makes its way through farm fields, leaving thousands of plants lifeless or inedible. The silkworm is a species that devours thousands of hectares of silk in China and is a big problem for the textile industry.

Approximately 12 families of moths or butterflies can cause serious problems for humans, as caterpillar hairs can contain venom, causing everything from urticarial dermatitis and atopic asthma to osteochondritis, consumption coagulopathy, kidney failure and intracerebral hemorrhage. Lonomy is the most common cause of poisoning in Brazil, with about 354 cases between 1989 and 2005, and with a fatality of up to 20% caused by intracranial hemorrhage.

Caterpillar hairs can cause serious problems for humans
Caterpillar hairs can cause serious problems for humans

Caterpillar hair also causes keratoconjunctivitis, produced by the affiliated barbs that contain the ends of the hairs. These barbs can be inserted into soft tissues or mucous membranes, which can be difficult to remove, causing a greater problem in the injury.

Popular culture

In some cultures, caterpillars are a rich food. In South Africa mopane caterpillars are eaten by the Bushmen and in China silk caterpillars are considered a delicacy.

In the Old Testament of the Bible, caterpillars have appeared to be feared for causing great plagues and were mentioned when they wanted to wish the sea on people.

In the past, the role of the caterpillar as a stage of metamorphosis was not widely accepted among scientists, since it was believed that insects generated spontaneously until in 1679, Maria Sibylla Merian published the first volume of Wonderful Transformation and Strange Floral Food from Las Caugas, which contained 50 illustrations and a description of insects, moths, butterflies and their larvae.

Butterflies were considered as symbols of the human soul since ancient times, and also in the Christian tradition. The metamorphosis from caterpillar to butterfly was a symbol, and even proof, of the resurrection of Christ. Since then, the metamorphosis from caterpillar to butterfly in Western societies has been associated with countless human transformations in folk tales and literature.

In Lewis Carroll's Alice in Wonderland, a blue caterpillar reflects with Alice about the changes they will both undergo. The caterpillar will become a butterfly and she a woman.

List of other interesting animals