Earwigs are common insects frequently found in gardens and occasionally indoors. Their distinctive appearance often sparks curiosity. This article clarifies their characteristics and behaviors.
Identifying Features
Earwigs, belonging to the insect order Dermaptera, are identifiable by several physical traits. Their bodies range from dark brown to reddish-brown, though some species may exhibit lighter markings. Most earwigs are small, measuring between 5 and 25 millimeters in length. They possess an elongated, flattened body shape and slender, thread-like antennae.
Their most notable feature is the pair of prominent, forceps-like appendages, known as cerci, located at the tip of their abdomen. These cerci vary in shape between sexes; males often have more curved pincers, while females typically have straighter ones. While most earwig species have two pairs of wings—a short, leathery forewing and a fan-shaped, membranous hindwing—they rarely use them for flight, preferring to scuttle or run.
Habitat and Diet
Earwigs thrive in dark, damp, and cool environments. Common outdoor habitats include areas under rocks, logs, leaf litter, mulch, dense shrubbery, woodpiles, and at the base of trees. They are nocturnal, becoming active at night to forage.
These insects are omnivorous. They primarily feed on decaying organic matter, such as composting leaves and dead insects, making them beneficial scavengers. Earwigs also feed on living plant material, including soft fruits, vegetables, flowers, and tender plant shoots. Some species are predatory, consuming small insects like aphids, mites, and spiders, which can be advantageous for gardeners. If earwigs venture indoors, they seek out moist areas like basements, bathrooms, and laundry rooms, often entering through cracks or gaps.
Are They a Threat?
Despite their intimidating appearance, earwigs are generally harmless to humans. Their pincers are primarily used for defense against predators, capturing small prey, and during mating rituals. While an earwig might pinch if handled carelessly or threatened, the pinch is rarely strong enough to break human skin and is typically more startling than painful.
A common misconception is that earwigs crawl into human ears to lay eggs or burrow into the brain; this folklore is unfounded. Earwigs are not venomous and do not transmit diseases to humans. Their presence indoors is usually a nuisance rather than a danger, often indicating a search for moisture or accidental entry.