Polymorphism
Many adult butterflies exhibit polymorphism, showing differences in appearance. These variations include geographic variants and seasonal forms. In addition many species have females in multiple forms, often with mimetic forms. Sexual dimorphism in coloration and appearance is widespread in butterflies. In addition many species show sexual dimorphism in the patterns of ultraviolet reflectivity, while otherwise appearing identical to the unaided human eye. Most of the butterflies have a sex-determination system that is represented as ZW with females being the heterogametic sex (ZW) and males homogametic (ZZ).
Genetic abnormalities such as gynandromorphy also occur from time to time. In addition many butterflies are infected by Wolbachia and infection by the bacteria can lead to the conversion of males into females or the selective killing of males in the egg stage.
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