9:07 a.m., March 30, 2009----On April 1, 1996, Taco Bell announced that it had bought the Liberty Bell from the federal government and was renaming it the Taco Liberty Bell -- which happens to be one of our personal favorite April Fools' gags. April 1 is just a few days away - are you ready with a practical joke or two?

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In the insect world, getting punked isn't exclusive to April 1. A number of insects have developed evolutionary strategies that are designed to fool their predators, says Brian Kunkel, an entomologist with University of Delaware Cooperative Extension.

And some are just as dramatic, in their own right, as Taco Bell's big stunt. Take the hoverfly, a native fly that, like bees, feeds on nectar and pollen. And, like the bee, it has yellow and black stripes. From a distance (and who wants to get too close to a bee, anyway?) the hoverfly looks a lot like a bee.

Which is precisely the point, says Kunkel. “The hoverfly's mimicry of the bee is an effective way to ward off predators,” says Kunkel.

If you want to be sure it's a hoverfly and not a bee, watch the way the insect flies. Hoverflies, as their name implies, have a characteristic flight pattern -- hovering in one spot, suddenly moving forwards or sideways, and then hovering again.

Other insects that engage in mimicry include the viceroy butterfly, which is an almost perfect copycat of the brilliantly colored monarch butterfly. The monarch has wings of red, orange, yellow and/or gold, with veins of black running through them. The viceroy has very similar markings, except for the fact that it has a black band crossing its lower hind wings.

For a long time it was thought that the viceroy was a Batesian mimic - which means it's a species that is palatable to predators but mimics the look of another species that isn't so tasty, such as the monarch. (Birds throw up if they happen to eat a monarch butterfly.) But research conducted in the 1990s demonstrated that viceroys taste just as nasty as monarchs do, which means they are referred to as Mullerian mimics.

As for why this was only recently discovered, Kunkel says that entomologists don't enjoy eating butterflies any more than the next person. But, as part of his doctoral defense, Kiunkel's professors made him eat a few viceroys. (Do you think Kunkel is punking us?)

In addition to mimicry, camouflage and deceptive behavior are two other common strategies that insects use to fool predators.

The walking sticks are an order of insects, more technically known as Phasmida, that look like -- you guessed it - sticks that can walk. Found in Europe, the U.S. and Australia, the insect's appearance resembles the plant life of the region in which it resides.

Walking sticks don't fly well and most don't even have wings. Those that do have wings keep them tucked in close to their body when not in use - giving them the appearance of a shriveled leaf. When they move, they rock back and forth as if being buffetted by the wind, just the way a twig on a tree would.

The larvae of the spicebush swallowtail butterfly take camouflage a (gross) step further. Early stages of the larvae are bumpy, blackish green and have white spots - making them look like bird droppings, and thus, certainly nothing a predator would want to dine on.

The mature spicebush swallowtail doesn't utilize camouflage but it does exhibit mimicry behavior. The lower edges of its bottom wings have tails that extend out from the wing margin just laterally to red eye-spots. These tails and eye spots are mimics of the butterfly's real antennae and eye structures. An attacking bird often grabs onto this false head, which gives the spice swallowtail enough time to fly away, minus, perhaps, a portion of its wing. (Even with missing lower wings, spicebush swallowtails are still capable of flight.)

One of Kunkel's personal favorite “tricky” insects is the underwing moth, which employs a two-pronged strategy involving both camouflage and deception. The moth's drab-colored forewings look like tree bark, which keeps most predators from investigating further. But if a predator does get close, the moth suddenly flashes its hindwings - which, at rest, lie tucked beneath its forewings. These hindwings are brilliant shades of red and yellow, colors that deceive the predator into believing that danger is imminent. The startled bird flees - and the underwing moth lives to see another day.

Article by Margo McDonough