Sexual dichromatism

Sexual dichromatism is a difference in coloration between males and females of the same species. It can involve color, brightness, pattern, or the presence of distinctive patches.

Sexual selection: Evolutionary change in traits that affect success in obtaining mates. Mate preferences and competition can favor coloration in one sex over the other.
Indian peafowl: A pheasant species in which males have elaborate iridescent trains and females are comparatively muted. Its conspicuous male plumage is a familiar example of sexual dichromatism.
Predation: An ecological interaction in which one organism kills and consumes another. Conspicuous colors can increase detection by predators, especially for individuals with exposed displays.
Natural selection: Differential survival and reproduction that cause heritable traits to change in frequency across generations. Predation and environmental conditions can favor sex-specific colors independently of mate choice.
Mate choice: Selection among potential mates based on traits that influence reproductive decisions. Preferences for colorful partners can drive sex-specific coloration.
Mallard: A widespread duck species whose breeding males have a bright green head and females have mottled brown plumage. The sexes' contrasting plumage makes the species a clear example of seasonal sexual dichromatism.
Camouflage: Coloration or patterning that reduces an organism's visibility against its surroundings. Muted coloration in one sex can improve concealment while the other sex displays brighter colors.
Antipredator adaptation: A trait that improves an organism's chances of avoiding or surviving predators. Whether muted female coloration evolved for concealment requires evidence beyond color contrast alone.
Intrasexual selection: Competition among members of one sex for access to mates. Color can advertise status or help rivals assess one another.
Mandarin duck: An East Asian duck species whose breeding males display ornate, brightly colored plumage. Its striking male colors contrast with the female's subdued patterning.

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