Figure 4. Associations between (A) saturation and the total concentration of pteridines; (B) hue and the concentration of drosopterin. Orange-red colored skin had higher concentrations of drosopterin than other skin colors (C). BL = black; BR = brown, CR = cream; GR = grey; O =orange, P = pink, R = red, RBR = red-brown, Y = yellow skin samples (N=180).
Table 1. Association between total carotenoid, total pteridine and the ratio of carotenoid to pteridine pigment concentration and environmental and sexual selection variables (N=186).