Mimicry and Camouflage
I think you must all have heard the story of the Monarch butterfly (Danaus plexippus) and its evil twin the Viceroy ( Limenitis archippus archippus). The Monarch has a noxious taste because of its favorite foodstuff (milkweed leaves), and birds quickly learn not to eat them. The Viceroy just tastes like generic butterfly. But the Viceroy looks enough like a Monarch that many birds who have learned the bitter truth about the Monarch will not touch a Viceroy. Here you see the Monarch who, as an adult, loves purple coneflowers and other Rudbeckia relatives , but when she is ready to lay her eggs, she deposits them one by one on a milkweed leaf, where they grow into large fat caterpillars with rings of white, yellow and black around them. (Viceroy larvae eat willow, poplar, aspen, and fruit (apple, cherry, and plum) leaves.) I haven't seen a Viceroy for years, but this picture was cropped out of a photo of some of my specimens that I saved from 1954.
Once the caterpillars have reached their ultimate fatness, they hang themselves upside down and make a pretty green chrysalis, which after a few days (10-12) becomes clear and shows an orange and black pattern inside. This means the chrysalis (the pupa) is ready to hatch as an adult and after some rest to fly away to start the adventure all over again. In fact, I do believe that the black with white dots (the body of the butterfly) is on its way out at the bottom of the chrysalis!
Remember that there is information in the name of the file for each image. You can see it by mousing over the image - look at the lower left of the screen. Or you can click on the image to get to the (usually) larger image. Then the info is displayed in the address line above. Sometimes the second click will actually display a different view of the original image.
Mimicry isn't limited to creatures imitating another of the same general shape, size and color. Here is a fly (Sparnopolius confusus) imitating a bee. Since most of the fly's predators are afraid of bees, they avoid this fly like crazy. There is even a whole family of flies who mimic various predator-types. Many of the hover flies look like wasps or bees. The last three flies on this row (three and four are the same species) are all wasp imitators. The first time I saw one of these large flies was while I was taking pictures in the goldenrod. The "wasp" flew towards me making a terrible buzzing sound. I was sure I was being attacked by a huge wasp. I finally backed away far enough for the attack to end. I didn't realize until I was cropping the day's haul of pictures that it had been a FLY!
Amazing fly from BG
I always get a thrill when I think I have found a new wasp, and this first one had all the right ingredients: yellow and black markings especially. But when I calmed down I saw the fly eyes - this one was a fly mimicking a wasp! and so are these next two...
Here's even a wasp mimicking a hover fly!
Here is a little table with some fly heads and some waspish ones. You can see how hemispherical the flies' eyes are. The wasps' heads have more variety in shape (some round, some squarish, some pointy).
Look at these cute colorful little moths. Or are they? Moths have 2 pairs of wings, these puppies only have one pair. Too bad the eyes are so small and well hidden by the fluffy "hair". But they really are flies.
Another creature that is shunned by humans is the mighty mosquito. It bears quite a lot of resemblance in shape and posture to the humble midge, of which there are biting and non-biting ones. At any rate, the midge defuses any hostility toward him/her by simply looking like its relative the mosquito. The first picture here is one of my favorite mosquitoes - it has the black and white banded legs of the Aedes genus?. The next two are midges, many of whom are innocent little things. Ooops, the midge in the middle is afflicted with a red parasitic mite. Note that male midges such as these are have elaborately fluffed up antennae. That's one way you know midge from mosquito.
Sometimes the difference in two or more creatures that look so similar is important. For the past two or three years two members of the Aedes genus, Aedes aegypti and Aedes albopictus, have been spreading tragedy in tropical and subtroptical regions of the world in the form of the Zika virus. Last mosquito season, I was pretty sure that I had seen A. albopictus, the Asian Tiger Mosquito, which is picture #1 in this row. But a friend showed me that what we get here (for now) in Michigan is actually Ochlerotatus japonicus, the Asian Rock Pool mosquito, and for now totally harmless. But the next two links are the real A. Aegypti and A. albopictus. Note that even though the Asian Rock Pool Mosquito has lots of white dots on black as well as the black and white banded legs, the A. albopictus has even more white dots on black. Note that A. Albopictus doesn't even show up in Michigan, though it is in Ohio and maybe in Michigan but just not reported. Maybe someone will report one this year.
Another group of flies that resemble huge mosquitos is the Crane Flies. Most of the adults don't eat much at all, but their larvae might eat larvae of other flies, like mosquito larvae. They also will eat roots of plants below the ground. You might like to look up "snow crane fly". Crane flies are almost always beautiful with unexpectedly patterned body and wings. Here we have a largish crane fly called the Tiger Crane Fly, one with a lovely pattern resembling a block-printed fabric pattern, and a mating pair. I must confess that I joined two pictures, one showing the female bright and crisp, the other the male. You get the point. Though it sounds opposite to us humans, the female's tail ends with a pointy section that can open to allow the male to enter. Confusing? Not to crane flies. After all, our genders have quite spectacular outward patterns. In most cases, the females are quite a lot larger than the males. That little whitish "thing" hanging from the female is the male. We'll talk later about the phenomenon of sexual dimorphism.
There is an amazing animal that I have never been able to catch on film (electronic of course). It is the so-called phantom crane fly. Its joints are bright white on black legs. It seems to float up or down and resembles a kind of fairy-like creature. I was quite awe-struck when I saw one floating around in the asters around the pond. But one day I found what must be one on my workshop siding. At least its joints were whitish. When I submitted it to Bugguide.net, I was nicely told that it was no such thing, but rather a Thread-legged Bug, and closer related to an Assassin Bug. Like the Assassin Bug, it has a long long tube hanging from its mouth, which is hard to see here because it is folded tight against its chest. It also has "hands" that look a bit like the way a praying mantis folds his or her last joints. When it spots a menu item, it extends its tube (rostrum)and grasps the item and then unfolds his mouthpart to suck the life from the item. We will come back later to carnivorous insects.
Phantom Crane Fly>
Many other orders of insects mimic other orders' members. Ants are a popular "mimickee".
Here is a nice Wiki article on mimicry
Here are some ant mimics from my yard (or so I believe or hope): The first may indeed be a cricket nymph behaving as an ant. Next is a jumping spider, while the third and fourth are the Lupine BUG: the nymph is the ant mimic, the adult is a beautiful pink BUG.
Another form of mimicry occurs when one creature's body is shaped and/or colored to look like a different object.
Here's the famous dead leaf butterfly. The top is (was 60 years ago) brightly colored while when the butterfly alights with wings folded looks amazingly like a dead leaf. Third is a walking stick insect.
Here is an old old film clip showing the gait of the walking stick as it braves the branches of a geranium. If that insect expects for its guise to work, it will have to stay still for a while. By the way, walking sticks eat only plant matter. Did you know that walking sticks, praying mantids, cockroaches, and grasshoppers USED to be in the same order, Orthoptera?? Well, with the use of DNA we now know they are all in separate orders? EXTRA! They have only in the past couple of years determined from DNA evidence that the termites are now in the Cockroach order. Can you imagine?
Let me just say that in the beginning of life, a creature may mutate to various forms and colors. Now if that mutation confers an advantage to the creature that has this mutation, we can say that the creature evolved to a new form. In the subsequent generations, that new form may continue to mutate and at each step the offspring with the mutation may become the preferred organism. It may produce a poison that keeps birds from eating it (each stage of this is a mutation) or it may be shaped in color, form, ability to fly (for instance) to a more viable group.
Mimicry is thus an example of the situation in which mutations are encouraged by natural selection.
A very interesting kind of evolution might be called parallel evolution. Here's an example in which some Orchids and Orchid-seeking Bees "force" changes in each other. Say that pollination of the orchid by the bee is most productive when the bee is hairy, and thus gathers more pollen from the orchid's "throat". Say that different bees have various "hairiness" factors. Now the bees head for the orchids. Say the hairiest bees thus cause most pollination, meaning that in the next generation of orchids, ones that were pollinated by the hairy bee are more plentiful than the other orchids. The orchid has achieved a benefit by being pollinated by the hairy bee. On the other hand, say the bee prefers the color blue (for example, actually I'm not sure any bees prefer blue) and suppose that a certain orchid comes in a variety of shades of color. The bees will flock to the orchids that are bluer than others. So in the next generation the bluer orchids have more offspring, and so after a number of generations there will be more and more blue orchids. The orchid AND the bees have influenced the evolution of each other.
In case you can't remember (me neither) the subtleties among the types of mimicry, here is a nice article on the various types, right out of the Encyclopedia Britannica.
Kinds of Mimicry
Top 10 Animals With Amazing Camouflage
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copyright Martha O'Kennon 2017