It's probably because of what Unfezent's based on and the sexual dimorphism in real-life birds.
Unfezent's Name Origin:
>While its pre-evolutions resemble wild pigeons, Unfezant most closely resembles a gamebird, such as a green pheasant, turkey or tragopan. It is also similar in appearance to the greater roadrunner. Unfezant's gender differences reflect sexual dimorphism in real-life birds in that males have large wattles and are more colorful than the females.
>Sexual dimorphism is a phenotypic difference between males and females of the same species, meaning that there are obvious differences between the male and female of the species. The main differences are the presence or absence of reproductive organs. However, more obvious differences are often secondary sex characteristics, such as size differences in males and females, ornamentation and behavior.
(Female (left) and Male (Right) Common Pheasant, illustrating the dramatic difference in both color and size between sexes.)
(Male (left) and Female (right), illustrating the dramatic differences in color.)
>Males of most species are more colorful than the females. Males often have elaborate courtship behaviors that include strutting, fluffing of tail or head feathers, and vocal sounds. They are mainly non-migratory.
>The green pheasant also known as Japanese pheasant, is native to the Japanese Archipelago, to which it is endemic. The male (cock) has dark green plumage on the breast and mantle. The male also has an iridescent violet neck, red bare facial skin and purplish green tail. The female is smaller than the male and has plumage ranging from light brown with dark spots to an all over dark brown.
>As in many galliformes, the male is larger and much more colorful than the female.