Final answer:
Most offspring in the mice population would likely have lighter fur color due to environmental selection against darker coloration, alongside the assumption that the lighter fur trait is genetically dominant.
Step-by-step explanation:
When predicting the fur color of offspring in a population of mice, several factors and genetic principles must be considered. Given the information that colored mice would not be selected for a dark coloration, it suggests that there is an environmental pressure that favors lighter fur colors, making them more fit for survival. In a scenario where darker fur might confer less fitness, we can reasonably expect that lighter fur colors would prevail in the offspring, according to the principles of natural selection.
Considering the genetics, if lighter fur is a dominant trait, similar to how Gregor Mendel observed that yellow pea plants were more common than green, and when he mated yellow plants, only yellow offspring were produced, the same could be expected for the fur color in mice. If all mice with a light fur color carry dominant genes for that trait, then most of their offspring would also have light fur. However, without precise genetic ratios or inheritance patterns provided in the drawing, a definitive prediction cannot be made.
If the information regarding a mottled agouti coat being dominant (as indicated in Figure 18.19) is relevant to the situation, and solid coloration is related to the recessive phenotype, then a population of mice possessing dominant agouti genes would produce mostly mottled agouti offspring assuming no genetic mutations or other epistatic interactions occur that could change the expected outcomes.