Illustration of the plumage colour scores for 398 parrot species. (a) L‐score distribution showing dark to light colours, (b) a‐score distribution showing green to red colours, (c) b‐score distribution showing blue to yellow colours, and (d) colour elaboration score of females and males showing the distribution from the average colour (greenish brown) to highly elaborate colours such as red, blue and yellow. Illustrations in each panel represent the species that have the minimum and maximum scores for each variable. (a–c) Shown are box plots with median (vertical line) and interquartile range (box), and violin plots (grey lines) showing the probability density of the data. The dots in (a–c) represent the colour of each species for each colour coordinate (averaged across 12 body patches). To show the colour score of each species on the L, a and b coordinates separately, variation in the focal colour coordinate is shown, whereas the other two colour coordinates were fixed (a, a = 0, b = 0; b, L = 50, b = 26.4 (mean score for all species); c, L = 50, a = −8.8 (mean score for all species)). Illustrations © Lynx Edicions