Deceptive Coloration |
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Deceptive coloration
is when an organism's color fools either its predators or its prey. There are
two types of deceptive coloration: camouflage and mimicry. CamouflageCamouflage helps an organism blend in with its surroundings. Camouflage can be colors or patterns or both. When organisms are camouflaged, they are harder to find. This means predators have to spend longer finding them. That's a waste of energy! Blending In: Stripes or Solids?There are lots of different examples of camouflage. Some colors and patterns help animals blend into areas with light and shadow. The American bittern spends most of its time hidden in the reeds. When a threat approaches, it either freezes in place or stretches its neck up towards the sky and sways back and forth. The stripes on its breast and belly look like reeds waving in the breeze, and a predator may be fooled! If that doesn't work, it calls out with its loud, booming voice and flies away! Other animals, like the bobcat, have spots that help them blend into their environment. Their spots work the same way the bittern's stripes do. The dark spots blend in with the shadows and the lighter fur blends in with lighter areas of their surroundings, like the sunlight shining on the plants around them. Disruptive Coloration - Break It Up Stripes and spots can be disruptive coloration. Disruptive coloration helps break up an animal's outline. This makes it difficult for other animals to see it. You'd think that the black and white stripes of the zebra would make it easy for predators to see it! The main predator of the zebra is the lion. Lions don't like to hunt in the heat of the day, they prefer sleeping in the shade. They hunt as it gets dark. As the sun goes down, the black and white stripes of the zebra help it blend into the tall grass. But the zebra's stripes have another purpose. Solid ColorSometimes an animal blends best into its environment when it is a solid color. The white fur of the polar bear is perfect for an arctic environment. Top and BottomAnother type of camouflage is called counter shading. Animals with countershading have different colors on their backs and stomachs. The red squirrel has reddish-brown fur on top and white fur on its undersides. The darker top fur makes it harder for predators to see the squirrel when it is on the ground. When it is perched on a tree branch, the white fur on its belly helps it to blend into the lighter sky above. | MimicrySome animals and plants look like other things -- they mimic them. Mimicry is another type of deceptive coloration. It can protect the mimic from predators or hide the mimic from prey. If mimicry was a play, there would be three characters. The Model - the species or object that is copied. The Mimic - looks and acts like another species or object. The Dupe- the tricked predator or prey. The poisonous coral snake and the harmless king snake can look a lot alike. Predators avoid the king snake because they think it is poisonous. This type of mimicry is called Batesian mimicry. In Batesian mimicry a harmless species mimics a toxic or dangerous species. Studies conducted in the early 1990's suggest that the viceroy and the monarch are actually examples of Mullerian mimicry where two equally toxic species mimic each other to the benefit of each. Just goes to show you that there's always something new to discover in the natural world! Can You Tell the Difference? Aggressive MimicrySome mimics look like something else, not to avoid predators, but to catch prey. Aggressive mimics resemble their background or signal that they are something else to help them catch their prey. The frogfish or angler fish lures its prey to where it can strike. It has a long antenna-like extension on its head that it wiggles. Other fish and crustaceans think its a little fish and come in close to eat it. When they do, the anglerfish eats them! Cryptic ColorationSome organisms look so much like another object that they almost disappear! The walking stick looks so much like a twig that it's easy to overlook it. Walking sticks are members of the Phasmatodea order of insects. There are over 2,500 species in this order and over 32 species in North America. Most species in this order are found in the tropics. Species in this order all have one thing in common - they are masters of disguise! Because walking sticks look like twigs and sticks it is very difficult for predators to spot them! Most species of walking stick have no wings or very small, non-functioning wings. Walking sticks also move slowly, so they don't attract predators. The katydid looks like a leaf. Katydids are also known as leaf bugs or bush crickets. Katydids are members of the grasshopper family. There are over 6,000 species of katydids in the world. The praying mantis can look like a leaf and a twig! The praying mantis is a member of the Mantidae family of insects. There are over 2,400 species of mantises found around the world. Eyespots: I'm Watching You!Some butterflies and moths have large eyespots. These eyespots trick birds into thinking the butterfly or moth is much larger than it really is!
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