Some squid change their skin color with a flick or a flash, scientists from Stanford University and the National Geographic Society report January 21 in the Journal of Experimental Biology. They outfitted Humboldt squid (Dosidicus gigas) in the Gulf of California with video cameras to see how the animals use their chromatophores, or color-changing skin cells.
Analysis of the footage revealed that the squid repeatedly flash red in the presence of other Humboldt squid, possibly as a way of communicating — though what, scientists aren’t yet sure. When close to the surface, the squids’ chromatophores flicker, giving their skin a hue of sunlight shining through the water column — possibly as a form of camouflage.