A black feathered cow bird hatches a chick that is white due to a mutation in the gene that makes the black pigment. This white bird manages to mate with a wild type black bird. The offspring are iridescent grey. Explain briefly how this mating resulted in the new color of cowbird.

Mutation induced incomplete dominance of the alleles

Explanation:

Mutation refers to any change in the nucleotide sequence of an organism's genetic material (DNA). In this question, the change affects the feather colour of a bird i.e. making a black feathered bird produce a white chick. The white chick produced can be said to be a "MUTANT" because it is a result of mutation in the feather colour gene.

When this mutant white feather colored bird mates with a wild type (naturally) black feathered bird, iridescent grey offsprings emerge. The change in colour can be attributed to INCOMPLETE DOMINANCE. This is because the mutation that occurred caused a change in the alleles making dominant allele incompletely dominant over the recessive pair. Hence, a third phenotype (grey), different from the two parental phenotypes (black and white), is produced.

hope this !