Walking sticks, or stick insects, are a group of highly camouflaged insects. They escape predation by blending into plant material. As their name suggests, they look just like sticks, and may even sway back and forth to more closely resemble a twig moving in the wind.
Depending on the species, walking sticks can grow from 1 to 12 inches (2.5 to 30 centimeters) long, with females usually growing bigger than the males. Stick insects are the biggest insects in the world—one species measures over 20 inches (51 centimeters) long with its legs outstretched.
Walking sticks are a favorite food of many animals, but perhaps their most effective predators are bats. Most bats hunt by echolocation rather than sight, so they aren’t fooled by the insect’s sticklike appearance.
When camouflage isn’t enough, some species have evolved the ability to release foul-smelling chemicals to deter predators, and others can secrete a liquid that temporarily blinds their foes. Others drop their legs when a predator attacks, but can regrow the appendages.
Walking sticks are one of many species that can reproduce parthenogenetically, meaning the females can produce unfertilized eggs that hatch and grow into new females.
The National Wildlife Federation