Earwigs are common insects belonging to the order Dermaptera, a name derived from Greek words meaning “skin wings,” referring to their unique forewings. They are easily recognized by the distinctive pair of pincer-like appendages, known as cerci, located at the rear of their elongated bodies. Earwigs are primarily nocturnal, active at night, and range in length from 5 to 50 millimeters. They possess two pairs of wings, though the membranous hindwings are rarely used for flight, remaining folded beneath leathery forewings.
Their Role in the Ecosystem and Gardens
Earwigs are omnivores, consuming both plant and animal matter. Their diet includes decaying organic materials like compost and leaf litter, making them valuable detritivores in the ecosystem. They also prey on soft-bodied insects such as aphids, mites, slug eggs, and insect larvae.
These insects prefer moist, dark habitats, found under rocks, logs, leaf litter, or in cracks. Their feeding habits can damage garden plants, as they chew irregular holes in leaves, flowers, and fruits of plants such as dahlias, zinnias, strawberries, and corn silks. This damage can resemble that caused by slugs, though earwigs do not leave a slime trail.
Despite their potential to harm garden plants, earwigs also provide beneficial services by consuming common garden pests. Their role in breaking down organic material contributes to nutrient cycling, supporting soil health and plant growth. This dual role means earwigs can be both a pest and a beneficial insect, depending on their population levels and available food sources.
Interacting with Humans: Behavior and Common Concerns
Earwigs are nocturnal and seek shelter during the day in dark, moist places like under debris or in cracks. When disturbed, they often drop to the ground and quickly scramble away to find new cover.
Their distinctive cerci, or pincers, are used for self-defense and capturing prey. These appendages also help fold their hindwings neatly beneath the forewings. Male earwigs have more curved pincers than females, which are also used during mating.
A persistent myth suggests earwigs intentionally crawl into human ears to burrow into the brain and lay eggs. Entomologists confirm there is no scientific basis for this folklore. The name “earwig” likely originated from Old English terms like “ear creature” or “ear wiggler,” possibly due to their hindwings resembling a human ear. While accidental entry into an ear canal is rare, it is not a deliberate action by the insect.
Earwigs are not known to bite humans. While they possess pincers, they are not aggressive and only pinch if handled or agitated, typically as a defensive reflex. Any pinch is minor, causing slight discomfort but rarely breaking the skin. Earwigs are not venomous and do not pose a significant threat to humans.