Old Geezer. 1950-2022
White-throated sparrow
The White-throated Sparrow comes in two color forms: white-crowned and tan-crowned. The two forms are genetically determined, and they persist because individuals almost always mate with a bird of the opposite morph. Males of both color types prefer females with white stripes, but both kinds of females prefer tan-striped males. White-striped birds are more aggressive than tan-striped ones, and white-striped females may be able to outcompete their tan-striped sisters for tan-striped males
White-throated sparrow
The White-throated Sparrow comes in two color forms: white-crowned and tan-crowned. The two forms are genetically determined, and they persist because individuals almost always mate with a bird of the opposite morph. Males of both color types prefer females with white stripes, but both kinds of females prefer tan-striped males. White-striped birds are more aggressive than tan-striped ones, and white-striped females may be able to outcompete their tan-striped sisters for tan-striped males