For many animals, being noticed can mean being eaten or scaring away a would-be meal. From the tiger’s stripes to the snowy owl’s downy white feathers, camouflage allows animals to hide in plain sight and avoid these perils. But camouflage is often about more than color. Some animals have skin texture that matches the texture of their environment. Other animals have shapes that make it hard to spot the outlines of their bodies.

Camouflage that matches one environment may stand out in another environment. This can be a big problem for animals that need to remain mobile. Cuttlefish, relatives of squid and octopi, handle this in an extraordinary way. They have changeable camouflage that adapts to new surroundings in a split second.

Cuttlefish change the color of their skin by covering or exposing many tiny colored spots, called chromatophores. These spots expand when the small muscles around them contract. Together, exposed chromatophores can create solid colors or complex patterns across the whole surface of the animal. Sometimes these patterns are mottled, resembling variation in the background colors. At other times the patterns don’t match the environment, but instead have high contrast with distinct edges. It might seem that these jarring patterns would stand out, but instead the false edges disrupt the outline of the body and mask its overall cuttlefish shape. This is the same strategy that led to dazzle camouflage, the bold patterns painted on ships to hide them at sea.

But the exquisite camouflage of cuttlefish is not limited to their color changes. They can also alter the texture of their skin. This is done with small organs called papillae. There are many papillae scattered across the skin. In their relaxed state, they are flat. Papillae have multiple muscle groups. When the circular muscles that ring the base of a papilla are contracted, the skin bunches up and the entire structure extends out. Other muscles control the shape of the extruded papillae, fine-tuning their texture. Those texture changes occur at the same time as the shifts in color brought about by the chromatophores, but little is understood about how these processes are controlled.