Look at this video. Don’t miss the part around 2:15 where they zoom in on the squid skin. For years I’ve seen these amazing videos of squids and octopuses showing how rapidly they can change color, but I never had any clear idea how they accomplished it.
It’s amazing to see the restless, boiling appearance of the chromatophores. These color-bearing cells take a constant amount of pigment and either squeeze it down so you can’t see much of it or squash it flat so you see a lot of it. Taken together it amounts to a large flexible low-power color display with a rapid refresh rate.
Say! When you put it like that, it starts to sound like a pretty cool technology. Which of course it is. As you might guess, human engineers are trying to learn from the canny cephalopod. Gamma Dynamics is a company that’s trying to bring chromatophore-inspired electrofluidic displays to an electronic display near you. It has a lot of attractive features: speed, low power, and color. But since it’s not here just yet, we can assume that it’s tricky to get it right. This IEEE Spectrum article on display technologies is clearly somewhat biased, since it was written by the principal scientist at Gamma Dynamics, but it’s a good overview.