Would You Rather . . . Have Body Armor or Colorful Camouflage?

An armadillo snuffles along, rooting through the dirt with its snout in search of delicious insects. In the shadows, a coyote crouches, ready to pounce on the unsuspecting critter. But the hungry coyote quickly discovers that the armadillo won’t make for an easy meal. That’s because it has  built-in protection against predators’ attacks: natural armor.

Overlapping bony plates along an armadillo’s back form a carapace, or hard outer shell. The plates are covered in scales made up of keratin, the same substance found in your fingernails. “When you touch an armadillo’s carapace, it feels sort of like a football,” says Jim Loughry. He’s a biologist and armadillo expert at Valdosta State University in Georgia.

Running away is an armadillo’s first line of defense. Loughry knows this from experience: He sometimes has to chase armadillos and capture them for his research. “They’re quicker than you would think!” he says. If speeding away doesn’t work, the animal will flatten itself against the ground to protect its soft underbelly, leaving only its tough shell exposed.

There are 20 species of armadillos native to parts of North America and South America. All have armor. But the three-banded armadillo, which lives in Brazil, takes this defense to the next level. It can roll up into a fully armored ball by tucking its head inside a notch in its pelvis. “Predators can sneak up on three-banded armadillos,” says Loughry. “But once they’re rolled into a ball, they’re pretty much invulnerable.”

An armadillo snuffles along. It roots through the dirt with its snout. The animal is searching for delicious insects. In the shadows, a coyote crouches. It’s ready to pounce on the unsuspecting critter. But the hungry coyote quickly finds that the armadillo won’t be an easy meal. It has built-in protection against predators’ attacks: natural armor.

Bony plates overlap along an armadillo’s back. They form a carapace, or hard outer shell. The plates are covered in scales made of keratin. Your fingernails are made of the same substance. “When you touch an armadillo’s carapace, it feels sort of like a football,” says Jim Loughry. He’s a biologist and armadillo expert at Valdosta State University in Georgia.

An armadillo’s first defense is to run away. Loughry knows this from experience. He sometimes has to chase armadillos and capture them for his research. “They’re quicker than you would think!” he says. If running doesn’t work, the animal will flatten itself against the ground. That protects its soft underbelly. Only its tough shell is exposed.

Twenty species of armadillos live in parts of North America and South America. All have armor. But the three-banded armadillo takes this defense to the next level. This armadillo lives in Brazil. It can roll up and tuck its head inside a notch in its pelvis. That way, it becomes a fully armored ball. “Predators can sneak up on three-banded armadillos,” says Loughry. “But once they’re rolled into a ball, they’re pretty much invulnerable.”

To avoid becoming a tasty snack for predators, octopuses rely on a sneaky trick. They change their appearance so they can hide in plain sight. “With its soft body, the octopus is extremely vulnerable,” says Alex Schnell, a marine biologist and wildlife filmmaker. “To defend itself, it had to become a shape-shifter.”

Octopuses have specialized cells in their skin called chromatophores. They contain colorful pigments that allow an octopus to turn nearly any shade. Their skin is also covered with bumps that the animals can inflate and deflate at will to change their skin’s texture. And they can mold their squishy bodies into just about any shape.

By combining these abilities, octopuses can make themselves look like almost anything in the sea. They can camouflage themselves, blending in perfectly with surrounding seaweed, coral, or sand. They can masquerade as objects, morphing to look like a rock or a floating piece of algae. Some can even mimic other animals: They might bury their body in the sand with two arms sticking out to look like a banded sea snake. Or they might float with their arms spread out to imitate the spiny fins of a lionfish.

As a last resort, some octopuses shoot out a cloud of ink to distract predators then swim away. “They’ve got a whole tool kit of tricks up their sleeves,” says Schnell.

Octopuses don’t want to become a tasty snack for predators. So they use a sneaky trick. They change their appearance and hide in plain sight. Alex Schnell is a marine biologist and wildlife filmmaker. “With its soft body, the octopus is extremely vulnerable,” she says. “To defend itself, it had to become a shape-shifter.”

Octopuses have specialized cells in their skin. These chromatophores contain colorful pigments. Octopuses can use them to turn nearly any shade. Their skin is also covered with bumps. The animals can inflate and deflate these bumps at will. That changes their skin’s texture. And they can mold their squishy bodies into almost any shape.

These abilities can combine to make octopuses look like almost anything in the sea. Octopuses can camouflage themselves. Then they blend in perfectly with seaweed, coral, or sand. They can mold into the shape of objects. They may look like a rock or a floating piece of algae. Some can even imitate other animals. They might bury their body in the sand and stick two arms out. Then they look like a banded sea snake. Or they might float with their arms spread out. That looks like the spiny fins of a lionfish.

As a last resort, some octopuses shoot out a cloud of ink. This distracts predators. Then the octopuses swim away. “They’ve got a whole tool kit of tricks up their sleeves,” says Schnell.