From National Geographic:
When Domenico Fulgione placed Moorish geckos on dark surfaces, he saw what he had seen for years. These spiny, hand-sized lizards changed colour. Within an hour, their typical creamy white complexions transformed into blacker hues that better matched their environment.
And then Fulgione blindfolded the geckos.
They still changed colour. How does an animal adjust its colour to match its environment, when it can’t see that environment at all?
Fulgione’s team found an important clue when they repeated their experiment and bandaged the geckos’ torsos, rather than their heads. This time, their camouflage failed. They could see perfectly well but with their flanks covered, they were less effective at matching their surroundings than their unrestrained or blindfolded peers. More.
Hey, it works. They don’t need to “notice” their surroundings, to react to them. But it’s still unclear why the back changes so quickly when most of the opsins (light sensors) are on the flanks.
Hat tip: Slawek Bioslawek