In a particular species of mammal, black hair (B) is dominant to green hair (b), and red eyes (R) are dominant to white eyes (r). When a BbRr individual is mated with a bbrr individual, offspring are produced in a ratio of 5 black hair and red eyes:5 green hair and white eyes:1 black hair and white eyes:1 green hair and red eyes. Which of these explanations accounts for this ratio? 1. Green-haired individuals have a higher prenatal mortality than black-haired individuals.
2. The genes for hair color and the genes for eye color are carried on different chromosomes.
3. The expected results did not take genetic recombination into account.
4. The genes for both of these traits are carried on the autosomes.
5. The genes for hair color and eye color are linked.