How Insects Hide in Plain Sight
Many insects pretend to be something they are not. Entomologist Dr. Art Evans and VPM radio producer Steve Clark explore camouflage and other related defense strategies that help insects to hide in plain sight.
Some insects are brightly and boldly colored, but most species are more somber in coloration. These species rely on some form of crypsis, such as camouflage, to conceal themselves and avoid becoming food for hungry predators. Grasshoppers, katydids, and stink bugs, among other insects, are usually found on specific backgrounds in their environment such as leaves, sand, and bark, that match their colors and help them seem to disappear.
While the colors of insects help them to blend in, some have the added advantage of having body shapes that render them less insect-like. As their common names suggest, stick and leaf insects look like specific vegetative structures that are of little or no interest to a hungry predator. Green lacewing larvae covered in bits of lichen are less likely to attract attention, too, as are caterpillars and other insects that resemble bird droppings. The resemblance of insects to various vegetative structures or inanimate objects such as feces, considered inedible from the point of view of a predator, is a form of crypsis called mimesis. Mimesis is not to be confused with mimicry, which involves the superficial resemblance of two or more unrelated species, mimics and models.
In Batesian mimicry, the harmless mimic derives the same protection from predation as afforded to the harmful model. For example, flies that are incapable of biting or stinging often mimic bees and wasps capable of defending themselves by delivering a painful sting.
In Mullerian mimicry, both the models and mimics are chemically defended with toxins. They collectively advertise this fact by sharing similarly bold colors and patterns known as aposematic or warning colors. The resemblance of monarch and viceroy butterflies to one another is a well-known example of Mullerian mimicry. Once a predator attempts to eat a Batesian model or a member of a Mullerian mimicry complex, it quickly learns to avoid all lookalikes.
For insects, it is all about eating or being eaten. To avoid becoming meals themselves, many insects engage in cryptic behaviors, including camouflage and mimesis, to avoid detection. Still others engage in forms of mimicry by resembling species that predators find harmful in some way.
Here’s another WBY animated video about insect defense strategies that involves a beetle looking like something it’s not.