Camouflage & Mimicry

The Assassin Bug glues the drained corpses of its victims onto its own back, building a tower of bodies taller than itself.

Why it works: When an assassin bug stabs prey with its sharp beak, it injects saliva loaded with venom and digestive enzymes -- special chemicals that break body tissue down into mush. This is digestion happening OUTSIDE the body: the prey's insides turn to soup so the bug can suck them up through its strawlike beak, leaving an empty shell. Scientists think the bug saves those shells and glues them on its back because the messy pile breaks up its outline, so a hunting spider can't tell it's a tasty bug -- though exactly why the trick fools predators is still being studied.

The Cuttlefish hypnotizes its prey by pulsing moving bands of color across its skin, freezing the target in place.

Why it works: The cuttlefish's skin is packed with tiny color sacs called chromatophores, and each one is ringed by little muscles its nerves can yank open or snap shut. Because muscles and nerves do the work (not slow chemicals), the color flips almost instantly, and mirror-like cells underneath bounce light to add blues, greens, and silver. When it hunts, it rolls dark stripes across its body; scientists think this swirling motion overloads the prey's eyes so the crab or fish can't tell the cuttlefish is creeping closer. And even though it is colorblind, it seems to match its background by reading how light or dark each spot is rather than the actual color.

The Glass Frog has see-through skin, so you can watch its heart beat through its body.

Why it works: A glass frog looks see-through because of what its blood is doing. Red blood cells soak up green light and shine back red, so flowing blood is the easiest part of the frog to spot against a green leaf. When the frog sleeps, it pulls almost 90% of those red cells out of its blood and tucks them into its liver, which is lined with tiny mirror-like crystals that hide their color. With the red cells stashed away, light passes through the frog's muscles and skin instead of bouncing off, so its outline blurs into the leaf and predators looking up from below can't tell where the frog ends and the leaf begins.

The Horned Lizard shoots a jet of its own blood up to five feet straight out of its eyes when cornered.

Why it works: A horned lizard has tiny muscles that can squeeze shut the big veins that carry blood OUT of its head. When it clamps those veins, blood keeps flowing IN but can't drain away, so it pools in spaces around the eyes and the pressure shoots up, like pinching a garden hose. That rising pressure swells until it bursts the thinnest, weakest blood vessels near the eyelids, firing out a jet of blood. The blood tastes terrible to dogs, coyotes, and foxes, and scientists think this is linked to the venomous harvester ants the lizard eats.

The Leafy Sea Dragon grows leaf-shaped flaps of skin that mimic floating seaweed so perfectly it becomes almost invisible.

Why it works: The leafy flaps aren't real leaves; they are thin lobes of skin (called dermal appendages) that grow out from the dragon's body in shapes that match floating, broken-up seaweed. Because they look and drift like the kelp and weed all around it, predators and prey can't pick out the dragon's outline, so it seems to vanish. The flaps do no swimming at all. Instead, the dragon glides by rippling two tiny see-through fins, one on its back and one near its head, fast enough that the moving fins are very hard to see, which keeps the seaweed disguise unbroken.

The Lyrebird can perfectly imitate a chainsaw, a car alarm and a camera shutter.

Why it works: Birds don't sing with a throat box like ours. They use a special organ called a syrinx, deep in the chest where the windpipe splits toward the lungs. Tiny muscles squeeze and stretch this organ while air rushes through, changing the pitch and shape of the sound, and a songbird can control its two sides separately to make two sounds at once. The lyrebird has an unusually specialized syrinx plus a great memory for sounds, which lets it copy almost anything; but scientists are honest that they don't fully understand exactly why this bird is such a perfect mimic when other birds aren't.

The Mantis Shrimp throws the fastest punch on Earth, at the speed of a bullet.

Why it works: The shrimp's club isn't powered by muscle alone. Muscles slowly bend a tiny springy, saddle-shaped piece of its shell, storing energy like a loaded bow, while a little latch holds it in place. When the latch lets go, all that energy releases at once, so the club shoots out at the speed of a bullet. It moves so fast the water behind it can't keep up and briefly turns to vapor, making bubbles that collapse with a flash of light and a burst of heat, adding a second hit. (Its eyes really do have up to 16 color receptors, but scientists found it doesn't see colors more finely than we do; it uses the extra receptors to recognize colors super-fast instead.)

The Orchid Mantis lures bees better than a real flower does, so pollinators fly toward it instead.

Why it works: A flower lures bees with its color and with the way it soaks up ultraviolet (UV) light, which bees can see but people cannot. The orchid mantis fakes both: its petal-shaped legs and body match the color and UV pattern of nearby flowers so closely that, to a bee's eyes, the mantis looks just like a blossom. The bee flies in expecting nectar, and the mantis's strong, spring-loaded front legs snap shut on it. Its shade can slowly shift between whiter and pinker as it grows, but scientists are still working out exactly what controls that change.

The Sea Otter holds hands while sleeping so it doesn't drift apart in the night.

Why it works: Sea otters have no blubber, so instead they trap a layer of warm air right against their skin. Their fur is so dense, up to about a million hairs in one square inch, that water cannot push through to reach the skin, and the trapped air acts like an invisible wetsuit. That is why otters groom for hours a day: combing in air bubbles and natural skin oils keeps the coat fluffy and waterproof. They also nap in groups called rafts, holding paws or wrapping in kelp so the current does not carry them apart while they sleep.