Nature can be harsh and unforgiving. In order to survive, animals around the globe have evolved to better blend into their environment. But in the animal world, blending in can look different from species to species.
Some animals, like the Vietnamese mossy frog (shown above), have evolved to match a specific habitat. Others, like multiple species of octopus, will shift their color as needed to blend in with new environments. And still others change colors seasonally so they can continue to hide from predators or prey in changing weather.
Each of these types of visual camouflage is known as “cryptic coloration.” And when it comes to cryptic coloration, there’s more than meets the eye!
How Basic Cryptic Coloration Helps Animals Blend In
If you’ve ever been hiking in the woods and didn’t notice a rabbit or deer until you were very close to it, you’ve seen cryptic coloration in action. Basic camouflage (technically called “concealing coloration”) lets animals blend in with their surroundings.
Deer spend a good bit of time in wooded areas, so their brownish coloration helps them to better blend in. Hares and rabbits usually are also colored similarly to their environments. The animal pictured above is a European hare — as you can see, its color is nearly identical to that of the stones around it.
The way this type of cryptic coloration works is obvious to us, but not all types of camouflage are. To us, the zebra’s bold stripes of black and white make it stand out more against the golden savanna. However, lions are the main predators of zebras, and they are color-blind. That means that the back and white stripes might blend in with the surrounding grasses (which also look black and white to lions).
However, more recent research suggests that stripes may not make it harder for lions to distinguish zebras from their backgrounds after all. Even if they don’t, the stripes have another purpose — they help the zebras blend into each other.
Zebras are herd creatures, so when they’re close together, the stripes make it harder for predators to distinguish individual animals. You can see that effect in the picture above.
In this context, the patterns of zebras work as something called “disruptive coloration.” This is a form of camouflage that breaks up (or disrupts) an animal’s outline so the animal is less visible to predators or prey.
Zebras aren’t the only animals that rely on disruptive coloration. Leopards are another great example.
It might seem like their striking, rosette-like spots would just make them more conspicuous. However, leopards often hunt in areas full of trees or other vegetation, and their spots help them blend in with the spots of sun reaching through the leaves.
Countershading: A Different Type of Camouflage
You may not be familiar with the term “countershading,” but you’ve almost certainly seen this type of camouflage in action. Countershaded animals have darker coloration on the dorsal part of the body and lighter coloration on the ventral (belly) side. Countershading can be found in a wide variety of land and sea animals.
Sharks (like the great white in the picture) are famously countershaded — the tops of their bodies are gray, and their bellies are white. Both shades help them camouflage.
If you view a shark from above, its darker gray body will likely blend in with the ocean. But if it’s viewed from below, its light belly will blend in with the sunlight filtering through the surface of the water. Sharks are hardly unique here — countless fish and other marine animals are similarly colored. Countershading also helps black and white penguins hide from predators.
This type of camouflage also appears in land animals, and it’s remarkably common. Why?
One of the main theories used to explain countershading is that of “self-shadow concealment.” In other words, the shading reduces the appearance of shadowing on the animal itself. As a result, the animal looks flat, and it becomes harder to spot.
Take a deer, for example. If a deer is standing in the sunlight, the upper part of its body casts a shadow on the belly. If the deer was just one color, the belly would look noticeably darker than the rest of the body, and it would be easier for a predator to spot.
However, when the deer’s upper body casts a shadow on the lighter-colored belly, the belly doesn’t look any darker than the rest of the body. With “self-shadowing” hidden, the deer becomes harder for would-be predators to notice.
Countershading and other types of cryptic coloration are remarkable in their own right. But as we’ll see in a moment, things get really interesting when animals start to be able to change their colors to blend in.
Quick Color Changes and Their Role in Camouflage
If humans decide to blend in somewhere, we have the luxury of changing our clothing — like putting on a camouflage-patterned jacket before going hunting. Animals can’t change into and out of clothing, but some do have the ability to change colors rapidly. In some cases, the color change can happen in seconds!
Chameleons are probably nature’s most famous color-changers. Many of their color changes are for social signaling purposes, but these fascinating lizards can also adjust their coloration to help them blend into their surroundings (to an extent).
Have you ever wondered how chameleons manage to change color? They use two kinds of cells, called dermal chromatophores and iridophores. Dermal chromatophores contain pigment, and that pigment can move around to alter the color of the chameleon.
Iridophores are cells that contain reflective crystals. Chameleons have the ability to stretch these iridophores, changing what wavelengths of light are reflected (and therefore what colors we see). Both types of cells interact to create an incredible range of colors. Some species like the panther chameleon (shown above) are so colorful they don’t look real!
Land animals aren’t the only color-changing ones. Octopuses can also change the color of their skin to blend in with their surroundings as well. However, many species take camouflage a step further by actually changing their texture.
These sea creatures have skin that is covered in small protrusions called papillae. By controlling the size of the papillae, they can make their skin look smooth, bumpy, or even spiky.
Take a closer look at the picture above — can you see that there’s an octopus hidden among the rocks and coral?
Seasonal Color Changes
Being able to change color on demand is incredible, but few species can do it. There are some species of animals that change color based on the season. Most of these animals live in areas with snowy winters. During the warmer months, they have brownish feathers or fur. As winter comes, they begin to turn white.
Some well-known species of birds and mammals that do this include the Arctic fox, the snowshoe hare, and the willow ptarmigan. The above image shows two willow ptarmigans in the process of molting into their winter plumage.
For centuries, this adaptation has helped different species of mammals and birds to hide from predators or conceal themselves from prey. But as Earth’s climate grows warmer, it has begun to cause them trouble.
Some parts of the world have started experiencing less snow than before, but the animals still turn white in winter. As a result, the adaptation that was supposed to help them camouflage actually makes them stand out. Scientists have begun to see some of these species decline in population in areas with less snow.
Other Elements That Improve Camouflage
Color is the most important element of camouflage. However, some animals have evolved to blend into their habitats in other ways.
One of the best examples is the satanic leaf-tailed gecko shown above. At first, it looks like a wet leaf. But when you look closely, you can see that it’s actually a lizard!
Stick insects also have a shape that makes them hard to spot in their surroundings:
Clearly, the shape of these animals plays a key role in helping them blend in. But color does, too. After all, if the satanic leaf-tailed gecko was bright yellow and the stick insect was vivid orange, predators would be able to spot them with no trouble at all.
Cryptic Coloration Is Everywhere
You probably don’t spend much of your day thinking about animal camouflage. If you don’t notice it, that’s a sure sign that it’s working!
But if you want to gain a new appreciation for the natural world, take some time to look for the animals you often miss. Maybe you’ll spot a flower crab spider blending into a bloom, or a patterned owl perched motionless in a tree. The closer you look, the more camouflage you’ll find.