What do you know today that you didn't know yesterday?

[Anomalocaris]

the amazing thing about octopus eyes is even though their eyes can only form monochromatic images,  because the chromatic aberration their pupil creates is continuous and under muscular control,   they may in fact be able to extract much more detailed color information from  a continuously varying monochromatic with chromatic aberration than could any vertebrate eyes, which relies on pigments sensitive to only 2 or three or at most 4 colors, so can only build up color perception from combinations of 2 or 3 or 4 primary colors.