Montshire Minute: Camouflage

Originally aired during the week of July 20, 1998

Monday

This is Neal at the Montshire. Or, perhaps it's NOT Neal at the Montshire. You see, I could be someone else, cleverly disguising his voice to SOUND like Neal. Why would I do that? Well, if the person knocking on my door right now is an encyclopedia salesman, I'd kind of like to keep a low profile. If, however, it's Ed McMahon waiting to tell me I've just won the publishers clearinghouse sweepstakes, I'd answer the door in a nanosecond. Some animals - the chameleon, for instance - are experts at adapting to their surroundings by changing their color, or blending in with their environment. This week on the program . . . excuse me while I see who's at the door. Oh, hey, Ed! Yeah, that's me! Neal! Wait . . don't go away . . . it's ME . . . No REALLY, I'm Neal . . . from the MONTSHIIIIIIIIRE!!!!!

Tuesday

The color of some animals depends on the season, or a stage of development. Some moths hatch as brown caterpillars, so they can feed off brown autumn leaves and hibernate on tree branches without being seen. Some moths can even change their color based on changes in the environment caused by humans. The peppered moth got its name because it has bright wings with dark spots. It could hang out on birch trees and keep a pretty low profile. But in some cities in England, after the industrial revolution had pumped tons of ash into the atmosphere, a rare variety of the peppered moth with darker-colored wings was able to blend in with it's new, soot-blackened world. This dark-winged species thrived because it was more difficult for predators to recognize than its paler counterpart.

Wednesday

What's black and white and red all over? If you said a zebra in a union suit, you . . . . have a weird sense of humor. But you also have good instincts for camouflage. One basic type of animal camouflage is called "disruptive coloring." In this case, the animal's markings don't blend in with the landscape. Instead, the markings are meant to confuse predators. The zebra is a good example. To us, the zebra looks almost garish--this horse with crazy black and white stripes. But to a lion, the zebra may look like a big Rorshact ink blot. The stripes break up the outline of the animal, making it less distinct to color-blind predators. It's believed that the zebra evolved from another horse-like animal that didn't have stripes. Rare foals born with white stripes might have survived due to their protective coloring. Through natural selection, this breed survived to become the modern day zebra.

Thursday

The word camouflage means "a whiff of smoke." The word wasn't invented until World War I, when military leaders discovered the advantages of making soldiers and equipment seem to disappear through the clever use of colors and patterns. But many creatures have long used the principles of camouflage to avoid predators or to sneak up on their prey. The North American underwing moth flattens itself so closely against the surface it rests on that its wings cast no shadow. You have to look really hard to see it when its resting on a tree trunk. Watch a South American tree frog hop around, and it's hard to see how its complex stripe pattern helps it stay concealed. But when the frog is at rest, with its legs curled under its body, the markings form a pattern of continuous stripes. The frog seem can seem to disappear in the surrounding vegetation!

Friday

Many animals are masters of disguise. The looper, a kind of inchworm that will eventually become a moth, is the spitting image of a small twig. Other creatures use a whole grab-bag of camouflage techniques during their lives. The tiger swallowtail larva bears a startling resemblance to a bird dropping. I'm telling you, the likeness is uncanny! Then, after it has molted, the caterpillar turns green to match the color of the leaves it feeds on. And, it develops a pair of false yellow eyes that gives it a vague "snakelike creature from the black lagoon" look. Finally, some animals disguise themselves to look like other animals. The caligo (CAL-i-go) butterfly has a pair of black bulls-eyes on its wings, surrounded by bright yellow circles. For a moment, perhaps the one moment it needs to escape a predator, the butterfly's outspread wings look like the startling night eyes of an owl.