The earwig (order Dermaptera) is a familiar insect found in gardens and sometimes inside homes. This creature is often misunderstood, recognized primarily by its elongated body and unique posterior appendages. The earwig’s true nature involves a complex balance of roles, ranging from a minor garden annoyance to a beneficial predator. To understand what an earwig truly does, we must separate its biological functions from the widespread myths surrounding its name.
Physical Characteristics and Habitat
Earwigs are small insects, typically 12 to 15 millimeters long, usually dark reddish-brown or black. Their defining feature is the pair of prominent, pincer-like appendages, known as cerci, located at the end of the abdomen. The cerci shape varies between sexes; the male’s are more curved, while the female’s are straighter. These appendages are used primarily for defense, mating rituals, and occasionally for grasping prey.
Earwigs are largely nocturnal. During the day, they retreat to dark, sheltered environments to conserve moisture and avoid predators. Their preferred habitats are damp locations, such as under mulch, stones, leaf litter, and wood piles in the garden. When conditions become too hot or dry, earwigs may seek refuge indoors, often found in moist areas like basements and bathrooms.
Their Dual Role in the Garden
Earwigs are omnivores, giving them a dual status in the garden environment. They can be pests that cause plant damage or beneficial contributors to pest control. As pests, they target the tender, soft tissues of plants, causing irregular holes in leaves and flower petals. They feed on vegetable seedlings, corn silks, and soft fruits like strawberries, which can be a nuisance to gardeners.
Despite their potential for destruction, earwigs also function as natural predators. They actively consume soft-bodied insect pests, including aphids, mites, and the eggs of other insects. They contribute to the regulation of pest populations by preying on these common nuisances. Furthermore, earwigs act as scavengers by feeding on decaying organic matter, assisting in decomposition and nutrient cycling in the soil.
Dispelling the Common Earwig Myths
The name “earwig” derives from an ancient, unfounded European superstition that these creatures crawl into the ears of sleeping people. This folklore claimed the insect would bore into the brain or lay eggs inside the ear canal, an idea modern entomology has shown to be baseless. Earwigs are attracted to dark, moist crevices for shelter, but they do not actively seek human ears. Accidental entry is possible, as with any small insect, but it is exceptionally rare.
The menacing appearance of the cerci contributes to an exaggerated fear of the earwig. These pincers are not venomous, and the insect does not possess a stinger or a bite that transmits disease. If handled, an earwig may use its cerci defensively to deliver a slight pinch. However, the cerci are not strong enough to break human skin or cause serious harm.