Animal Camouflage: Nine Creatures Hiding in Plain Sight

Camouflage at a glance

Crypsis: being hard to see at all, by matching color, texture or brightness
Masquerade: being easy to see but read as something boring, like a dead leaf or a broken stump
Disruptive coloration: breaking up the body outline so the eye cannot assemble an animal
Shadow elimination: fringes and flaps that stop the body casting the giveaway dark line
Active change: skin that rewrites itself in about a second, which only a few animals can do

Camouflage is the oldest design brief in nature, and the solutions are more varied than the word suggests. Some animals match a background. Some pretend to be an object nobody bothers looking at. Some carry equipment whose only job is to stop their own shadow from giving them away. And a few rewrite their entire surface in under a second.

Here are nine that do it exceptionally well, sorted by the trick they use rather than by how startling they look, which turns out to be a better way of seeing what is actually going on.

Pretending to be something boring

A satanic leaf-tailed gecko from Madagascar shaped and veined like a dead leaf, clinging to a branch — Satanic leaf-tailed gecko, Madagascar. Photo by Brian Gratwicke, CC BY 2.0.

The satanic leaf-tailed gecko of Madagascar is not trying to be invisible. It is trying to be uninteresting. The body carries leaf veins, the tail is notched as though an insect has been at it, and the edges curl the way a dry leaf curls. This is masquerade rather than crypsis: a predator sees it perfectly well, identifies a dead leaf, and moves on.

A ghost mantis shaped like a curled dead leaf, with a crest on its head and flared leaf-like limbs — Ghost mantis, Phyllocrania paradoxa. Photo by Mydriatic, CC BY-SA 3.0.

The ghost mantis works the same angle with a different budget. The crest on its head, the flares along its legs and the asymmetric twist of its body all say withered leaf, and it will rock gently on its feet to complete the impression of something moving in a breeze.

A great potoo perched upright on a bare branch, its grey and brown plumage matching the bark — Great potoo. Photo by Charles J. Sharp, CC BY-SA 4.0.

The great potoo, a bird that can reach two feet long and weigh more than a pound, spends the day sitting bolt upright on a broken branch and being mistaken for the rest of it. Its plumage of grey, white, black and burgundy matches bark, and the posture does the rest. It hunts at night, when the disguise is no longer needed and the size suddenly is.

Erasing the outline and the shadow

A mossy leaf-tailed gecko with lichen-patterned skin and fringed flaps along its body and limbs, lying flat on a wooden surface — Mossy leaf-tailed gecko, Uroplatus sikorae. Photo by Hexasoft, public domain.

The mossy leaf-tailed gecko, another Madagascan Uroplatus, solves a subtler problem. An animal pressed against bark still casts a thin dark line where its body stops and the tree begins, and eyes are extremely good at finding lines. So this gecko grows a fringe of skin flaps along its jaw, flanks and feet that spread against the bark and dissolve the edge. It can also shift its skin tone to sit closer to whatever it is lying on.

A lichen huntsman spider flattened against lichen-covered bark, its fringed legs erasing its shadow — Lichen huntsman spider. Photo by Kramthenik27, CC BY-SA 4.0.

The lichen huntsman spider arrives at the same answer from a completely different branch of the tree of life. Mottled grey and green body, legs fringed with hair, and a habit of flattening itself so hard against lichen that the shadow has nowhere to fall. Two animals with no common design ancestor, both concluding that the edge is the tell.

Matching the background you were dealt

A pale speckled peppered moth resting on lichen-covered bark, nearly invisible against the pattern — Peppered moth on lichen. Photo by Ben Sale, CC BY 2.0.

The peppered moth is the most famous camouflage story in biology, and it is really a story about the background changing. The pale speckled form disappears against lichen. When industrial soot killed the lichen and blackened the bark of English cities, a dark form that had been a rarity rose to a reported 98 percent of the Manchester population by 1895. From about 1962, as the air cleaned up, the dark form fell away again.

In the 1950s Bernard Kettlewell put numbers to the mechanism: in polluted Birmingham birds took 75 percent of the pale moths, while in unpolluted Dorset they took 86 percent of the dark ones. In 2016 researchers found the mutation itself, a transposable element of nearly 22,000 base pairs sitting in the cortex gene. One accident, one century, one visible consequence.

Ptarmigan in all-white winter plumage standing in snow, visible mainly by their dark eyes and bills — Ptarmigan in winter plumage. Photo by A S Begbie, CC BY-SA 4.0.

The ptarmigan does not wait for evolution. It moults, from mottled brown and grey in summer to near total white in winter, so that the background it needs to match is the one it currently has. In the snow it is reduced to a black eye and a black bill, which is why photographs of ptarmigan so often look like photographs of nothing.

A pygmy seahorse gripping a gorgonian sea fan, matching its pink stalks and knobbly texture — Pygmy seahorse in a gorgonian, Lembeh Strait. Photo by Steve Childs, CC BY 2.0.

The pygmy seahorse takes background matching to its logical end. It lives its adult life on gorgonian sea fans, and its body carries tubercles that echo the size, color and spacing of the coral polyps around it. A full grown adult is around two centimetres. Divers generally find one by finding the right sea fan first and then waiting.

Rewriting the surface in real time

A cuttlefish hovering over the seabed with banded skin patterns running across its body — Cuttlefish. Photo by Victor Micallef, CC BY-SA 4.0.

The cuttlefish is in a different class. Its skin carries up to 200 chromatophores per square millimetre, each able to expand its surface area by 500 percent, and the animal can change its appearance in about a second. It does not only change color. It changes pattern, contrast and even the physical texture of its skin.

The strange part is that cuttlefish cannot see color. They have a single visual pigment, and yet they match colored backgrounds convincingly. The leading explanations involve their unusual W-shaped pupil and a high resolution sense of polarised light, which carries contrast information that color vision would otherwise supply. An animal that is colorblind, doing some of the best color matching in the ocean, is a good reminder that nature rarely solves a problem the way we would.

How to actually spot them

Stop looking for animals. Look for the things camouflage struggles to hide: a shadow with no obvious object, an outline that repeats where the background does not, a texture that is right but a scale that is wrong, and above all an eye. The eye is the hardest part to disguise, which is why so many of these animals have a dark stripe through it, a fringe over it, or the habit of closing it and waiting.

More strange and beautiful biology sits in our nature archive, and the terms above are unpacked further in our visual culture glossary.

Image credits: photographs by Brian Gratwicke, Hexasoft, Ben Sale, Charles J. Sharp, Kramthenik27, Steve Childs, A S Begbie, Victor Micallef and Mydriatic, via Wikimedia Commons, used under the CC BY 2.0, CC BY-SA 3.0 and CC BY-SA 4.0 licenses, or in the public domain.