“Who is the master of disguises?” asks the little green nymph covered in its own spittle of froth. But no one answers because Geometrid caterpillars dressed as twigs don’t talk. Neither does the flower crab spider who has been awaiting unwitting prey for days on a yellow petal answer, feeling that to do so might involve then having to find another flower. Having to change his color again might take too much effort.
Nature is the expert at the art of deception. A white twig is on my window and when I touch it, the twig flitters off. In the meadow I find foam between the goldenrod leaves. On further investigation, the green nymph of the spittlebug is hiding inside. There are many insects that imitate other animals, plant parts, or even stuff like spittle. The idea behind these simulations is to defend against predation, or to create deception in order to gain prey. Such adaptations for mimicry in physical form and behavior display the amazing evolution of natural selection.
The buff-tip moth is so convincingly a look-a-like for the birch twigs where she lays her eggs that one would never notice her. She is the color of silvery birch, with a head that looks like the broken end of a birch twig and tail tips of similar, freshlysnapped twig color. One minute there is a twig, and the next moment it takes wing and is gone. So too, plume moths resemble twig-like structures.
How many thousands of years, I wonder, does it take to evolve physical characteristics to something one is not? Does one just lean into the tree and spend so much of their life sharing a oneness with that species that over time they become, themselves, a mirror image? Is it like dogs who are said to grow to look like their owners over time? Or couples who in their elder years also begin to resemble one another? Can I, too, lean against a tree for years and begin to resemble it in form? Would my offspring become more and more tree-like if they did the same? Adaptations take time, unless you are, say, a fruit fly. Fruit flies lay about 500 eggs at a time and create a new generation each week. It only takes them about a month to take on a new trait or two.
Camouflage is one of the most notable of all avoidance and protective adaptations. So is playing dead, like the opossum does; but the famed opossum isn’t the only one to imitate a corpse. Hog nose snakes do it. So do male nursery web spiders and some insects. Spiders don’t like eating dead things (believe it or not, they prefer live prey). I recently showed some children at Cumming Nature Center the tough little ironclad beetle that looked oh, so deceased, only to wait a few minutes for it to come back to life and wiggle its six little legs in the air in my palm.
The hawk moth, also known as sphinx moth, uses both camouflage and a shock factor threat for protection. These moths have a bark-like appearance on their powdery wings, but if that doesn’t work, and a predator gets too close, they flash their underwings. Their underwings have markings that resemble brightly colored eyes of something that might be a larger predator than the one about to eat them.
Fear of being eaten, over eating a meal for one’s self, is the nuance here.
If none of these methods work, one can always just imitate the predator they are trying to avoid. Some moths imitate wasps. Tropical metal mark moths of the Brenthia Genus have evolved to mimic their top predator—the jumping spider. They do this with amazing wing color patterns that suggest the shape and eyes of the jumping spider while they, the moth, still maintain their own Lepidoptera form. From a bird’s-eye view, it’s not so convincing, but get down level with a spider’s eye view, and the illusion is more evident. Jumping spiders do not eat other jumping spiders, so being a look-alike spider from the spider’s multiple eyes’ view is a perfect mimicry costume.
One of the most classic examples of mimicry in the Leperdoptera world is that of the monarch and the viceroy. We have all been repeatedly told that the monarch, who feeds primarily on the toxic plant juices of milkweed is thus toxic to birds so they won’t eat them. The viceroy, it has been said, mimics the color pattern of monarchs so they will also be considered distasteful. This belief is now what is termed an old wives’ tale (although I personally believe old wives are quite wise). Studies show that the viceroy is equally as toxic as the monarch. In this case of who is mimicking who, maybe the real question is “who chose their coat of arms first, the monarch or the viceroy?”