Final answer:
Coat color in animals like rabbits shows discontinuous variation because it is controlled by a limited number of alleles resulting in distinct phenotypes, unlike continuous variation where many genes determine a trait with a range of phenotypes.
Step-by-step explanation:
Coat color is an example of discontinuous variation because it is determined by a limited number of alleles that produce distinct and separate phenotypes, rather than a range of phenotypes. For instance, in rabbits, there are four alleles for the c gene which determine coat color. The wild-type allele results in brown fur, chinchilla allele leads to black-tipped white fur, the Himalayan allele causes black fur on extremities and white elsewhere, and the albino allele produces white fur. The existence of a dominance hierarchy means that when individual rabbits with different alleles are bred, the resulting offspring will exhibit a clear coat color based on the dominant allele they inherit, rather than a blend of the parental colors.
This concept contrasts with continuous variation, where traits such as human height show a range of phenotypes due to the influence of multiple genes (polygenic inheritance). Gregor Mendel chose to work with discontinuous traits in his pea plant experiments, which enabled him to discover the basic principles of inheritance that showed traits are passed down in distinct classes rather than blended.