There are more than 20,000 different species of known caterpillar found all around the world and it is estimated that there are many more that are undiscovered as new species of butterflies and moths are regularly found in regions where there is little, of any, human presence.
Caterpillars difference in size, colour and appearance depending on their species. Some caterpillars are very brightly coloured where other caterpillar species are quite dull-looking in comparison. Some species of caterpillars are very hairy, where others are very smooth. The main aim of the appearance of the caterpillar is to intimidate it's predators and to deter them from eating it.
The caterpillar, like the butterfly, is a herbivorous animal but the diets of the caterpillar and the butterfly are very different. Butterflies use their long straw-like tongues to drink the nectar out of flowers, which is an adaptation that occurs in the process where the caterpillar becomes a butterfly. Caterpillars mainly feed on leaves, plants and flowering plants and big holes can often be found in leaves indicating the presence of a caterpillar.
A number of species of caterpillar are known to be carnivorous and eat a variety of insects that pass them. One caterpillar species found in Hawaii, hooks itself onto a leaf where it stands very straight trying to catching passing bugs.
Due to their small size and worm-like shape, caterpillars are preyed upon by numerous different species of animal but the main predators of the caterpillar are birds and large insects such as wasps. Caterpillars are also commonly preyed upon by small mammals and reptiles.