To add to the idea that the UV patterns might help pollinators get information on flowers usefull to them, there is some evidence that in addition to attractive colors and scents, the flower also signals electrically to at least some insects, such as the bumble bee. The hairs on the body will bristle as the charge difference between the negative-my charged flower and the positively charged beef is reflected in the bristle movement, as they arecrepelked from each other.
Flowers that have a bee on it or recently taken the nectar have a lower electrical charge and the incoming needs can sense that!
Asher