To determine the color of a dog's fur with the genotype aabb using the provided Punnett square, we can observe the results associated with the genotype aabb.
From the table you provided:
- AAbb = brown
- Aabb = brown
- aaBb = yellow
- aabb = (information not filled in, but we need to deduce based on the earlier examples)
Since the genotype in question is aabb and looking at similar genotypes in the information provided, we can conclude:
- aaBB and aaBb are yellow,
- AAbb and Aabb show brown.
However, there is no specific case for aabb in the given colors, but typically, for the aabb genotype, it results in a phenotype color.
Based on common genetic patterns, if the presence of the recessive alleles (in this case, 'a' and 'b' alleles) overpowers the prominent dominant alleles, typically it results in the fur being yellow for the aabb combination.
Therefore, the answer is: yellow