We’re back at my home base, the Michigan State University Museum, and today we’re taking a closer look at cryptic coloration, better known as camouflage. Whether furry or feathered, scaly or shelled, herd dweller or loner, a wide range of animals use camouflage to grab or avoid becoming dinner. Following is a brief description of the various ways animals conceal themselves through camouflage.
Aposematism – Is the use of bright colors to warn predators that they are toxic. A ladybug’s bright red, orange and black markings warn birds and other predators to find dinner elsewhere or risk an upset stomach. Some animals cleverly use aposematism as camouflage by mimicking the coloring and markings of a less tasty relative. A good example is the harmless and no doubt more palatable scarlet king snake. It sports rings of red, black and yellow similar to its venomous cousin, the coral snake. A handy way to tell them apart is by the old saying, red to yellow, kill a fellow; red to black, venom lack. Keep that in mind next time you’re tiptoeing through the Florida Everglades.
Background Matching –Just like the name indicates, animals camouflage themselves by blending into their surroundings. Chameleons are best known for their color matching skills. This defense mechanism is a form of protection, as well as a warning to fellow chameleons that predators are near. Click on the following link and watch a chameleon changing color not once, not twice but multiple times, including several different shades of green — Chameleon Changing Color Clip.
Polar bears are another example of background matching. Their white fur helps them blend into their snowy climate, but did you know their skin is actually black? The willow ptarmigan also sports a white coat in the winter. Twice a year this Canadian grouse molts its feathers, alternating between white in the winter and gray or brown in the summer.
Countershading – Animals that use countershading have dark bodies with lightly colored underbellies. Sharks are good examples of countershading. Above water their deep gray bodies are but mere shadows innocently circling beneath you. If, however, you’re snorkeling along the ocean floor, a shark’s lighter belly will blend in with the brighter water near the surface. Watch any of the Jaws movies and you’ll witness the chilling effect.
Disruptive Coloration –Stripes or spots that contrast from dark to light is another type of camouflage. These distinct patterns break up the outline of an animal and confuse the eye. For example, a single zebra, standing (or running like hellfire!) within its herd, is difficult for a lion to pinpoint because all the lion sees is a mass of moving stripes. Similarly, the contrasting stripes on a tiger, conceal its shape. Tigger can skulk undetected in the brush and pounce on unsuspecting prey.
Mimicry – Animals that use this type of camouflage, look or act like an object or another animal. Insects, in particular, are good at mimicry. The walking stick resembles a stick, the katydid mimics a leaf, and the owl butterfly and io silk moth both have big brown spots on their wings that look like an owl’s eyes.
Next time you’re strolling through the park or catching a wave, I encourage you to take a moment and witness nature’s many examples of cryptic coloration. And if you catch sight of any teeth, make like a zebra and run like hellfire.
Fun Squirrely Facts: The California ground squirrel chews up the discarded skin of its most hated enemy, the rattlesnake. It then spits out and applies the spittle to its fur. This isn’t some war paint-type ritual, but instead, a means of masking its squirrely scent. If a rattlesnake slithers by, it will smell a potential rival and back off. Click on this link to witness this gross but clever form of olfactory camouflage.
Fun Scottish Facts: My previous two posts highlighted several castles in the Scottish Highlands. I was delighted to find myself back in the land of kilts and castles while conducting research for this post. It turns out Scottish highlanders were the first to wear ghillie suits to hunt deer and other wildlife. A ghillie suit is clothing designed to blend into a particular environment, such as a forest, desert, jungle, and so on. In 1900, the Lovat Scouts, a Scottish Highland sniper regiment, were the first to use ghillie suits in the military.
Next week, we’ll be getting our Michigan on with a tour through the Michigan History Museum. It just so happens that yesterday, January 26th was the state of Michigan’s 180th birthday. See you next week 🙂
Sources:
365 Reasons to be Proud to be Scottish (2013), by Richard Happer
Museum Bites 