SRA

The White-throated Sparrow is a passerine bird of the American sparrow family Emberizidae, which has been studied extensively as it maintains a 100Mb inversion polymorphism on chromosome 2 via disassortative mating. The inverted arrangement is maintained in a near constant state of heterozygosity. Approximately half of the population is homozygous for the ZAL2 arrangement, whereas the other half of the population has the heterozygous condition. The exceptional inversion polymorphism (ZAL2m) in the white-throated sparrow (Zonotrichia albicollis) is linked to variation in plumage, social behavior and mate choice, and is maintained in the population by negative assortative mating.