Most people don't pay attention to caterpillar, because they are not nearly as interesting as butterflies, but it turns out that some caterpillars actually are!! Look at this one, for instance; could anyone actually say this is not a cool caterpillar?!?!
This beautiful caterpillar is a Colobura dirce, and the butterfly is known as Dirce Beauty, Mosaic, or Zebra Mosaic. It can be found in South and Central America, and two subspecies are recognized: Colobura dirce dirce, and Colobura dirce wolcotti. It shares the Colobura genus with only one other species, the Colobura annulata; the caterpillars of this species has white stripes, and the spikes are orange instead of yellow.
Caterpillars are the larval stage of butterflies and moths. Eating and storing energy for the transformation into the adult stage is what they do.
The bristles, or setae, are a defense mechanism for many species. Although some do not cause irritation, others have urticating hairs that cause irritation, and there are two types of urticating hairs: envenomating hairs, which are hollow and filled with venom, and when touched, the tips break off allowing the venom to be released; and non-envenomating hairs, which do not produce or contain venom, but are sharp and can easily penetrate the skin, causing irritation. Because predators experience extreme discomfort when they try to eat such caterpillars, the species with non-irritating bristles are left alone, since predators are not capable of differentiating the two.
Aside from the spines, caterpillars have other strategies to stay alive: some rely on camouflage, others mimic other animals. Many caterpillars have feeding behaviors that allow them to remain hidden; many feed in protected environments, such as rolled leaves, enclosed inside silk galleries, or by mining between the leaf surfaces. Some have long "whip-like" organs attached to the ends of their body, which they wiggle to frighten away flies and predatory wasps. Others can evade predators by using a silk line and dropping off from branches when in danger. There are those that thrash about violently, to scare away potential predators, and one species even makes a high pitched sound that scares away birds.