Caterpillar

Caterpillars hold an outsized niche in most terrestrial food webs: they are some of the most efficient small herbivores on the planet, and a critical high-energy food source for thousands of species of birds, predatory insects, and small mammals. A small share of caterpillar species are classified as agricultural pests, capable of causing extensive damage to commercial crop yields, while a small number are intentionally cultivated by humans, most notably silkworm caterpillars that produce the raw material for global silk production. In mainstream culture, caterpillars are a common symbolic shorthand for transformation, most famously appearing as the contemplative hookah-smoking character in Lewis Carroll's Alice's Adventures in Wonderland and the titular character of Eric Carle's classic children's book The Very Hungry Caterpillar.

While many laypeople think of caterpillars as a relatively uniform worm-like form, the group has evolved a vast range of extreme defensive traits that are rarely covered in general reference materials. Many species have evolved stinging venomous hairs, camouflage that perfectly mimics plant foliage or even fresh bird droppings to avoid predator detection, or mimicry that makes small caterpillars appear to be venomous mini snakes to scare off threats. Their distinctive crawling motion, which uses sequential contraction of segments along their body length, is the original inspiration for the name of the major heavy equipment brand Caterpillar Inc., a secondary namesake that is far less widely known than the insect itself.