Dynamic blinking in the head of hardyhead silverside fish

Abstract

Dynamic light reflection can serve a similar purpose to tools such as digital line processing devices. It is interesting, therefore, that evidence of dynamic light reflection can also be found in the animal kingdom and that there may be alternative ways of actuating light control. This study discovered that several features contained in the heads of hardyhead silverside fish, particularly around the edges of the iris, caused blinking using environmentally scattered light. Analyzing the blinking using recorded video of the fish iris revealed that circular cells existing in the iris changed their light intensity at 2 Hz. These 5-10-m-diameter cells are normally blue. However, it is found that a distinct light intensity changed in 0.04 seconds, and additional green and yellow colors overlapped with the blue. It is hoped that utilizing the mechanism that controls the rapid changes in light intensity using only environmental lighting can reduce electrical power usage in display devices.