The genetics of plumage phase dimorphism of the southern giant petrel macronectes giganteus

Abstract

1. Two plumage phases of the southern giant petrel Macronectes giganteus were recognised: White and dark. 2. Family data, consisting of observations on 208 single-chick families, were in agreement with the hypothesis that the dimorphism is controlled by two autosomal allelic genes with white phase dominant to dark. 3. Mating frequencies did not differ significantly from those expected with random mating. 4. No evidence was found for differential chick mortality. © 1970, The Genetical Society of Great Britain. All rights reserved.