Kate D. L. Umbers has published an interesting manuscript, titled “On the perception, production and function of blue colouration in animals”. Its available for free at the Journal of Zoology here and covers those studies that have proposed a function for blue coloration in the animal kingdom, taking a multi-disciplinary approach before taking you on a discussion of “blue”. What initially grabbed my attention was Table 1. A non-exhaustive list of visual pigments of various taxa showing the wavelengths at which their opsins are maximally sensitive. After that, it was easy to get sucked into the discussion of production of blue, pigmentary and structural blues as well as the crux of the paper which is the functions of blue.
As an aside, if you ever get a chance to see Robert Marc’s lecture on color, do it. Its magnificent. His discussion of the color blue from the physics to the neurobiology is truly wonderful.