Fig. 1
From: Transcontinental patterns in floral pigment abundance among animal-pollinated species
Ultraviolet (UV) and visible absorption spectra of major pigment groups contributing to flower coloration. Due to their structural diversity and distinct contributions to floral coloration, phenylpropanoids were categorized into hydroxycinnamates, UV-absorbing flavonoids, aurones-chalcones, and anthocyanins. The spectral region corresponding to each pigment type is color-coded based on the human perception of reflected light from petals. The violet-shaded area highlights the UV-A and UV-B regions of the light spectrum (400–315 nm and 315–280 nm, respectively) and shows that hydroxycinnamates and UV-absorbing flavonoids are the pigments with the highest light absorption capacity in this range. For each group of pigments, a normalized absorption spectrum of an example compound is shown (see Methods). The structures of p-coumaric acid (hydroxycinnamate), quercetin (UV-absorbing flavonoid), cyanidin (anthocyanin), betacyanin (betalain), lutein (carotenoid), and chlorophyll a (chlorophyll) are depicted.
