Final answer:
The scenario described is an example of directional selection, where lighter-colored mice on a sandy beach are favored over darker-colored mice, leading to a shift in the population's genetic makeup toward lighter coloration.
Step-by-step explanation:
The situation described where mice living on a light sandy beach are experiencing predation by storks more intensively if they are of a darker coloration is an example of directional selection. This form of natural selection favors the lighter-colored mice, as they are better camouflaged against the sandy environment, which leads to increased survival and reproduction rates of these individuals over the dark-colored mice. Over time, the population shifts toward the lighter colors; this is a change in the population's genetic variance toward the phenotype that is better suited to the environmental conditions and hence has a higher fitness. This process is similar to that observed in the peppered moth during the Industrial Revolution in England.