The talented octopus and the cuttlefish have clever ways to camouflage themselves, including changing the pattern and texture of their skin to look more like the rocks or coral where they're hiding. The mimic octopus can actually make itself look like other animals. But squid are out in the open ocean and need other tricks to hide from predators. So, they put on a special show of color, with skin flashing colors so quickly and dramatically that it can almost look like a computer's screen saver.
KQED writes, "To actually control the color of their skin, cephalopods use tiny organs
in their skin called chromatophores. Each tiny chromatophore is
basically a sac filled with pigment. Minute muscles tug on the sac,
spreading it wide and exposing the colored pigment to any light hitting
the skin. When the muscles relax, the colored areas shrink back into
Pigment in the skin are like little water balloons that expand and contract, allowing squid to put on what looks like a light show over their bodies. (Photo: KQED)
Using this incredible strategy, squid change the way light bounces off their bodies by changing the patterns of pigment in their skin. The goal is to mimic sunlight dancing in the water, in such a way that they become essentially invisible. The effect is absolutely mesmerizing, and it's hard to remember this is an animal's skin and not a television screen! The video below explains how they do it, along with footage of the hypnotic color shifts happening: