Answer:
The pocket mouse is generally found in rocky outcrops in the deserts of the southwestern United States and Mexico.
Though the fitness of an organisms helps them to survive and produce offspring but the color of pocket mouse influences its fitness because the color of mouse helps them to survive from the predators. The rock pocket mouse having light color fur blend with dark sand and blend with the sand which increases their chances of survival and the allele for dark fur will be passed on to their offspring.
Hence, color of pocket mouse or rock pocket mouse influences its fitness.
