Earwigs: Myths, Biology & Why They're Actually Beneficial

Earwigs (order Dermaptera, ~2,000 species) are among the most misunderstood insects. They don't crawl into ears or bore into brains. They're harmless to humans and mostly beneficial in gardens.

Anatomy

• Body: Elongated, flattened, 5–50 mm; flexible abdomen.
• Cerci (forceps/pincers): Pair at abdomen tip. Males: curved, caliper-like. Females: straighter. Used for defense, prey capture, mating, wing folding.
• Wings: Short leathery forewings (tegmina); intricate membranous hindwings folded beneath. Most can fly but rarely do.

Habitat & Diet

• Moist, dark: leaf litter, mulch, under bark/stones, basements.
• Omnivorous: decaying plants, fungi, algae, aphids, mites, small insects. Minor live-plant damage in some species.
• Nocturnal; attracted to lights.

Myth vs. Reality

Myth	Fact
Earwigs crawl into ears and eat brains.	No evidence. Name from Old English "ēare wicga" (ear insect)—likely from wing shape or rare accidental entry.
They pinch painfully.	Cerci pinch is weak; no venom. Defensive only.
They're destructive pests.	Mostly decomposers & predators of aphids/mites. Minor crop damage only.

Life Cycle & Behavior

• Gradual metamorphosis: Egg → nymph (4–6 molts) → adult.
• Maternal care: Females guard eggs/nymphs, clean them, protect from mold/predators—rare in insects.
• Sound: Some males stridulate (hiss/click) via abdominal spiracles.
• Defense: Cerci pinch; some secrete foul-smelling quinones.

Ecological Role

• Decomposers: recycle organic matter.
• Predators: consume aphids, mites, insect eggs—beneficial in gardens.
• Prey for birds, toads, spiders, centipedes.

Management (If Indoors)

• Reduce moisture; remove debris near foundation.
• Seal entry points (doors, windows, vents).
• Traps: rolled damp newspaper, oil-filled cans.
• Insecticides rarely needed; not structural pests.

Earwigs indicate a healthy, moist ecosystem. If you see them outside, thank them. If inside, dry it out.