Incomplete Dominance - Andalusian Chickens
1. Incomplete dominance is a form of alternate inheritance in which one allele is not completely dominant over the other.
2. Since one of the alleles is not dominant it creates a third phenotype in the offspring.
3. The third phenotype is a blend of the recessive and dominant phenotypes that the parents possessed.
4. Incomplete dominance only is apparent in the heterozygous offspring.
5. It is also called semidominance.
1. The cross-breeding of the black and the white Andalusian chicken produces the blue Andalusian chicken.
2. The ratio of these chickens offspring are 25% black, 50% bluish gray, and 25% white/splash. That is a 1:2:1 ratio.
3. Mendel actually used these chickens in his studies of genetics.