eyespots

Eyespots are circular or ring-shaped markings that resemble eyes. They occur in many animals, but are especially common in insects such as butterflies and moths. On many species they appear on wing surfaces as conspicuous spots or rings.

Most eyespots are not real eyes; they are pigment patterns that create the illusion of a pupil and iris. A typical eyespot has a dark outer ring, a lighter surrounding ring, and a central darker patch, producing a striking contrast.

Functions include predator deterrence and misdirection. When threatened, some butterflies flash their hindwings to reveal the eyespots, startling or deterring attackers or directing strikes toward the wings away from vital organs. In some cases eyespots also serve to confuse predators by breaking the animal’s outline.

Eyespots vary in size, number, and placement among species. In Lepidoptera, large hindwing eyespots are common and may vary with age or season. Caterpillars and other life stages may display eye-like patterns to deter predation.

Evolutionary origin: Eyespots have arisen independently in multiple lineages (convergent evolution) and have been studied as examples of anti-predator coloration. Research with birds indicates predators can learn to avoid eyespots over time.

Beyond insects, some reptiles and amphibians also show eye-like markings that can serve a defensive function, though the term is most often used for wing patterns in butterflies and moths.