Earwigs are common insects found across the globe, instantly recognizable by their distinctive appearance. They belong to the scientific order Dermaptera, a name that translates to “skin wings,” referring to their unique wing structure. While often regarded with apprehension, the earwig is a fascinating component of many ecosystems, primarily living outdoors. This article explores the earwig’s physical traits, debunks the myth behind its name, and details its role in the natural world.
Physical Characteristics and Identification
The typical earwig species measures approximately one-half to three-quarters of an inch in length. They possess a reddish-brown to dark brown or black coloration with an elongated and flattened body. Like all insects, their body is segmented into a head, thorax, and abdomen, featuring six legs and a pair of long, thread-like antennae.
The most prominent feature is the pair of pincer-like appendages, known as cerci. These cerci are muscular and used for defense, capturing prey, and courtship rituals. The sexes are distinguished by the cerci: males generally have more curved pincers, while the female’s tend to be straighter. Although most species have two sets of wings, including short, leathery forewings, they rarely use them for flight.
The Origin of the Name
The name “earwig” is the source of much misunderstanding and persistent, unfounded superstition. Common folklore suggests these insects crawl into the ears of sleeping people, a belief that is entirely false. Historically, the name likely originated from the Old English words Δ“are (ear) and wicga (insect), essentially meaning “ear creature.”
Some entomologists suggest an alternative origin, pointing to the insect’s intricate hindwings. When unfolded, the membranous hindwings are semicircular and resemble the shape of a human ear. Earwigs do not seek out human ears to lay eggs or bore into the brain, and the chance of one accidentally entering an ear is extremely rare.
Habitat, Diet, and Behavior
Earwigs prefer to live in dark, cool, and damp environments. They are commonly found outdoors hiding under leaf litter, mulch, decaying wood, rocks, and in soil crevices. They may occasionally enter homes seeking moisture, often found in damp basements or crawl spaces.
The earwig is primarily nocturnal when foraging for food. Their diet is omnivorous, consisting of decaying organic matter, molds, and various plants; they also feed on small insects and aphids. Females exhibit maternal care, which is uncommon among insects. The mother guards her eggs in an underground nest, cleaning them regularly and protecting the newly hatched nymphs until their first molt.
Impact on Humans and Gardens
Earwigs are considered a nuisance pest when they congregate in large numbers or find their way inside a residence. In the garden, their omnivorous diet can cause minor damage, such as chewing holes in soft fruits, flowers, and the tender leaves of seedlings. However, they also play a beneficial role by preying on soft-bodied garden pests like aphids and insect eggs.
Despite their menacing appearance, earwigs are not venomous and do not transmit diseases to humans. While they can pinch a person if handled or accidentally trapped against the skin, their cerci are not strong enough to cause serious harm. The pinch is generally harmless, resulting in only a momentary sensation.