How can you determine if a hen-feathered male is heterozygous?

To determine if a hen-feathered male is heterozygous, the appropriate approach is to mate him with an HhZW female. In this case, the male can display the hen-feathered trait but may possess either one or two alleles for that trait. By mating him with a female that is heterozygous (HhZW), the combinations of alleles can be observed in the offspring.

If the male is heterozygous (Hh), the expected offspring would show a 1:1 ratio of hen-feathered to cock-feathered males. This means that half of the males would inherit the dominant H allele from the female (resulting in a cock-feathered phenotype) and half would inherit the recessive allele from both parents, leading to hen-feathered males. This ratio would support the conclusion that the male is indeed heterozygous since both phenotypes are observed among the male offspring.

Conversely, if the male were homozygous (HH), all male offspring would exhibit the cock-feathered phenotype, and if he were to mate with a hen-feathered female (hhZW), all male offspring would display the cock-feathered trait. Therefore, only