In the animal kingdom, it is often eat or be eaten. Because of this, many animals have developed some defense mechanisms to keep them safe from predators.
Some of the most well-known defense mechanisms are also the most effective. Take skunks, for example, which are famous for their bad-smelling spray. Others defense mechanisms are pretty weird, like the Texas horned lizard. These lizards can squirt blood from their eyes to keep predators away. And don’t forget about opossums. They pretend to be dead to save themselves from attack.
One of the less celebrated animal defense mechanisms is camouflage. Many animals rely on their coloring to help them avoid detection. In the animal kingdom, there are four types of camouflage: concealing coloration, disguise, disruptive coloration and mimicry.
Concealing coloration is when animals blend in with their surroundings, and disruptive coloration is when an animal has a pattern like spots or stripes that make it difficult to see its outline. Camouflage by disguise is when an animal looks like something else to help it blend in. Mimicry is when a harmless animal looks similar to an animal that is poisonous or venomous.
Among the better-known animals that rely on camouflage are those that turn white in winter, like Arctic foxes. These foxes live in the Arctic tundra, and their fur changes color with the seasons. In the summer, they are brownish-gray in color, allowing them to blend in with the plants and rocks of the tundra. In the winter, they turn white so they can escape detection in the snow.
A little closer to home is the snowshoe hare, which also changes color throughout the year to better blend in with its surroundings. Snowshoe hares live in parts of the United States, including the Rocky Mountains, the Appalachian Mountains, the Pacific Northwest, New England and parts of Michigan, Minnesota and Montana. In the winter, snowshoe hares are white, helping them blend in with the snow. During the warmer times of the year, they are reddish-brown.
Here’s a look at some of the animals that live all around us that stand out for blending in.
Brown creeper
Many songbirds seem designed to stand out. Take the scarlet tanager and northern cardinal, both of which are hard to miss with their bright red plumage. Or blue jays, which are also easy to spot. But not the brown creeper, which blends in almost perfectly with tree bark.
These small, sparrow-sized birds have mottled brown backs and heads. This allows them to remain unseen while doing what they spend most of their time doing — traveling up and down tree trunks looking for insects to eat.
Their camouflage is so good that it’s often easier to identify a brown creeper by its song than by searching tree trunks to find one. Only the male birds sing, and it’s a high, sweet-sounding song. They are sometimes said to sound like they are calling out “trees, trees beautiful trees.”
Owls
While many songbirds seem to stand out in their surroundings, many owls seem designed to blend in. Several of the owls that populate our forests are difficult to see in even the best of circumstances, and not just because they are nocturnal.
Great horned owls are mostly nocturnal, but even by day these large owls are difficult to spot because of their barred brown, gray, black and white markings that help them blend in well in their forested habitat. Even their ear tufts, which aren’t ears or horns but skin projections covered in feathers, help owls camouflage themselves.
Words to know
Cavity: An empty space in a solid object.
Erythrism: A condition that causes redness in an animal’s fur, feathers or skin.
Mimicry: The act of imitating someone or something.
Nocturnal: Active at night.
Vegetation: An assemblage of plants.
Like great horned owls, eastern screech owls are also masters of camouflage because their markings help them blend in with the trees. They also often tuck themselves into small tree cavities, peeking just their heads out on a sunny day.
Snowy owls utilize camouflage too, but only in winter. Unlike Arctic foxes and snowshoe hares, snowy owls are white all year. They spend their summers in the tundra in far northern Canada and then head south to other parts of Canada and the northern United States, sometimes traveling as far south as southern Illinois. During the winter, their nearly all-white feathers help them blend in with the snow.
Bitterns
Both American bitterns and least bitterns are wading birds, and their markings make it difficult to see them among the tall grasses near the water’s edge where they like to hang out. Bitterns eat aquatic animals. While hunting, they stand still at the edge of the water and wait. Then they jab their bills into their catch.
Both American bitterns and least bitterns have streaked breasts that help them blend in, but American bitterns have the better camouflage. The longs streaks on their breasts spread upward to their necks, making them difficult to see in the vegetation where they stalk their prey. While their coloring helps them blend in, they are also difficult to notice along the water’s edge because of their ability to stand still for so long.
Walking sticks
You could be looking right at a walking stick and never know it because they are so cleverly disguised, blending in with the plants they live on. These bugs are so well camouflaged that they actually look like sticks with legs.
The world is home to more than 3,000 species of walking sticks, and each has camouflage designed for their specific habitats. Most are green or brown, but walking sticks can also be gray, black or even blue, depending on what they need to blend in with.
As good as their camouflage may be, walking sticks are preyed on by some creatures. To help them from becoming eaten, many walking sticks have developed other defense mechanisms as well. Some can emit a bad-smelling substance to keep predators away. Others flash their wings as a warning to predators, and still others can use their wings to help them quickly drop to the ground to escape danger.
Katydids
Of the more than 6,000 species of katydids in the world, most are green, which helps them blend in with the plants where they live.
In addition to their green color, katydids often have wings that are shaped like leaves, another feature that helps disguise them. A condition called erythrism affects about 1 in 500 katydids, causing them to be pink instead of green. In nature, this is not beneficial for the insects because they lose their ability to blend in.
Among insects, it’s not just katydids and walking sticks that are good at blending in. The world of insects is actually full of masters of camouflage. Take the dead leaf butterfly, which looks like a dead leaf, making it difficult to spot. The orchid mantis looks like part of the flower from an orchid plant, and the sand grasshopper almost perfectly blends in with the sandy soils where it lives.
Weasels
A few mammals we see locally, like white-tailed deer, use concealing coloration and disruptive coloration to help them blend into their environment, but weasels are one that take it to another level. Like Arctic foxes and snowshoe hares, some species of weasels change color during the year to help them avoid being seen.
In the summer, the back, sides, tail and head of least weasels and long-tailed weasels — the only weasel species that live in Illinois — are a reddish-brown color, and their underparts are white. In the winter, many weasels turn fully white to better match their sometimes snowy habitat. During spring and fall, the weasels can have a mix of white and reddish-brown fur as the color transformation is taking place.
This color change is more common in weasels that live in northern Illinois because snow is more common here. In areas where snow is not as common, weasels often develop white patches on their reddish-brown coats.
Gray tree frogs
Gray tree frogs are small frogs that live in the woodlands near waterways. There’s a good chance you’ve never seen one, but not because of their small size. Instead, it’s because these frogs can change color based on their environment and activities, helping them blend in no matter where they are.
These frogs, also called chameleon tree frogs, can change color because the shape of their pigment cells changes in response to conditions such as light and temperature. In low light or when temperatures drop, the pigment cells expand, making their skin appear darker. When there’s more light or temperatures increase, the shrinking cells make them appear a brighter color.
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