“…Male individuals of various avian species exhibit conspicuous colours on their feathers evolved by sexual selection driven by mating preferences ( M. Andersson, 1994 ; Darwin, 1871 ; Solis, Aviles, de la Cruz, Valencia, & Sorci, 2008 ), such as the males of the cooperative breeding azure-winged magpies ( Cyanopica cyanus ), where only a fraction access the breeding status. These birds display conspicuous blue plumage colourations, and all males that become breeders have a more brilliant and more saturated blue colouration, with a more intense violet hue compared with the nonbreeders ( Solis et al., 2008 ). The additional capacity of avian ornaments to reflect UV plays an important role during sexual displays ( S. Andersson & Amundsen, 1997 ; Bennett et al., 1997 ; Finger & Burckhardt, 1994 ; Finger, Burkhardt, & Dyck, 1992 ; Hausmann, Arnold, Marshall, & Owens, 2003 ; Hunt et al., 2001 ; Parker, 1998 ; Siitari et al., 2002 ).…”