Quick Change Artists

It's Here Somewhere...
But where? Try to spy the cuttlefish in this image of image of a coral reef in the coastal waters of Indonesia. To see if you're right, proceed to the next slide.

Gotcha!
Because cuttlefish are such masters of disguise, they are elusive study subjects in the wild, and some species may yet be undiscovered. (There are thought to be roughly 100 species worldwide, living in oceans almost everywhere except the icy poles and the Americas.) Cuttlefish tend to live in complex environments with ample hiding spots like coral reefs and mangrove swamps. But the variety of colors and textures in these environments also tests their quick-change abilities.

Animal or Plant?
A cuttlefish's skin can be as smooth as a polished rock, as bumpy as a brain coral, or as spiky as seagrass, and all these different textures can appear on a single animal, morphing from second to second. Cuttlefish rely on special cells in their skin called papillae to carry out these transformations. The cuttlefish at right also seems to be crimping the eight legs on its head to mimic the surrounding environment.

Solids, Checks, and Stripes
Matching the color patterns, as well as the tones, of its background is key to the cuttlefish's camouflage success. Its skin can show dozens of seemingly different patterns, but according to biologist Roger Hanlon, all these patterns fit into three basic types: uniform, mottled, and disruptive. Hanlon thinks this simplifies the task of blending in; a cuttlefish can quickly perceive enough visual cues to jump into one of the three modes, then take more time to refine the pattern it needs to stay hidden.

Standing Out
The Flamboyant cuttlefish, Metasepia pfefferi, seems like no other. This diminutive creature, just a few inches long, walks rather than swims, and it sometimes uses its skin-changing skills to call attention to itself. Like all cuttlefish, it has pigment-containing cells called chromatophores, and it changes its skin color by contracting or expanding the muscles around various chromatophores. But the Flamboyant often opts for flashy reds and yellows when predators are near, signalling to them that it is poisonous

Macho Males
When thousands of Giant cuttlefish, Sepia apama, congregate in the waters of South Australia to breed, male rivals display their bravado with striped body patterns. They can maintain these zebra stripes for hours and seem to wear them like war paint to intimidate challengers. Big males, stretching well over three and a half feet long, indeed look menacing even to human divers.

Cross-Dressing Males
With between four and 11 males for every female on the breeding ground, competition among Giant cuttlefish is fierce. Smallish males, rather than duke it out, take on the guise of females and try to sneak their way to matings. In this image, a male with the mottled color pattern of a female cruises under a large male and toward a female. Females are usually quite receptive to these mimics, and the mimicry is so effective that it sometimes fools other cross-dressers, leading two mimics to try to mate with each other.

A Dazzling Show
A few species of cuttlefish, including the Broadclub cuttlefish, Sepia latimanus, and the common European cuttlefish, Sepia officinalis, use their skin-changing abilities to mesmerize prey. All cuttlefish have in their skin not just chromatophores containing pigment but also two kinds of reflective cells, iridophores and leucophores, which influence color and, even more remarkably, can make the skin appear luminous. As they hunt, the Broadclub and European cuttlefish seem to turn on virtual strobe lights in their bodies, and shrimp and other prey fall victim to the act.