Common earwig
The common earwig, a member of the Dermaptera order, is one of over 2,000 species found globally, except in polar regions. Recognizable by its distinctive pincers, or cerci, located at its rear, this insect typically measures about 1/2 inch in length. Despite its appearance, the common earwig is harmless and prefers to remain hidden. These pincers serve multiple purposes, including defense against predators, capturing food, and attracting mates.
Common earwigs are omnivorous scavengers, feeding on both plant material and small insects, and are most active at night. They create homes in dark, damp environments, such as under rocks, tree bark, and in gardens. Female earwigs lay between 20 to 50 eggs, which they care for until hatching, after which they continue to nurture their young for several days. While myths suggest that earwigs can crawl into human ears, this is unfounded; they are not dangerous to people. Overall, the common earwig typically lives for about 1.5 years, contributing to the ecosystem by aiding in decomposition.
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Common earwig
The common earwig is one of the most common and well-known of the 2,000 species of earwigs. They are common to all continents on Earth outside of the polar regions. Their most notable feature is a set of pincers that protrude from their rear tip. Although the pincers make it look dangerous, earwigs are harmless and prefers to stay out of sight.
Kingdom: Animalia
Phylum: Anthropoda
Class: Insecta
Order: Dermaptera
Family: Forficulidae
Genus: Forficula
Species: Auricularia
The pincers, or cerci, serve several important survival functions. Their primary use is for defense against predators. They are also effective for hunting and capturing food as well as to attract a mate. The pincers are normally brown or black.
The common earwig's flat, dark body may grow to be 1/2 inch (a little over one centimeter) long. It is one of the smaller types of earwig, some of which grow to be one to two inches (2 1/2 to 5 centimeters) long. The flat, smooth body of the common earwig has sections connected by joints. These joints give the earwig great flexibility in moving its body and also enable it to flip its pincers forward over its back.
As with other insects, the common earwig has six legs and crawls and scurries much of the time. When it needs to fly, it pulls back the pair of small, hard wing coverings, called elytra, and spreads its large, thin, skin-like wings. After landing, the earwig folds these wings into 40 layers and places them under their protective coverings again so they are not torn when it is crawling.
Two long antennae extend from the earwig's flat head, which can rotate in several directions as the antennae sense the earwig's dark surroundings for food. When the antennae sense an insect, the earwig flips its cerci, forward over its back and seizes the prey. The antennae also detect fungi spores, flowers, fruit, and dead flesh, called carrion. Earwigs are omnivores. This means that in addition to plants, it also consumes animal material. On its nightly scavenging trips the earwig is in danger from other insects, birds, and rodents. It defends itself with its cerci. It is also threatened by homeowners, gardeners, and farmers who consider it a pest.
The common earwig makes its home in dark, damp places, such as rock crevices and underneath tree bark, as well as in similar places in the walls and floors of homes and in gardens.
The common earwig generally lives alone, but a mating pair may spend the winter together and occasionally join other earwigs. The earwig's sex, or gender, can be determined by the size of its cerci. Males generally have a larger cerci than females. The male and female mate in late summer or fall or possibly in spring. The female lays between 20 and 50 white or cream, oval eggs and cares for them until they hatch three to four weeks later. The mother continues to care for the nymphs, or young, for 10 days until they molt for the first time. Molting means they shed the hard shells of their bodies when new and larger ones have developed underneath. Each of these growth stages is called an instar. They leave the nest after the second instar, and the family remains together until the young are fully grown at the end of the summer when the nymphs have passed through four or five instars. Earwigs often live to be around 1 1/2 years old.
The sharp cerci on the rear end of the common earwig have caused many people to think that the earwig is dangerous and fierce. Some people have even believed that the earwig crawls inside people's ears and pierces their eardrums. This is likely where the insect obtained its name. This idea is only a myth, and the common earwig is actually quite harmless.
Related species:
- European earwig (Forficula auricularia)
- Spine-tailed earwig(Doru aculeatum)
- Ring-legged earwigs (Euborellia annulipes)
Bibliography
Blades, Nicole. “Earwigs.” WebMD, 3 Sept. 2022, www.webmd.com/skin-problems-and-treatments/what-are-earwigs. Accessed 2 Apr. 2024.
“Earwig.” A-Z Animals, 2024, a-z-animals.com/animals/earwig. Accessed 2 Apr. 2024.
Vincent, Morgan. “Forficula Auricularia European earwig.” Animal Diversity Web, 2013, animaldiversity.org/accounts/Forficula‗auricularia. Accessed 2 Apr. 2024.