Does female plumage coloration signal parental quality?A male removal experiment with the bluethroat (Luscinia s. svecica)

Females in several sexually dimorphic species with conventional sex roles possess ornamental traits that resemble those found in males. The evolution of such traits, however, is still poorly understood.

P.T. Smiseth and T. Amundsen, Behav Ecol Sociobiol (2000) 47:205-212