A population of small fish lives in a lake with a sandy bottom. The major predator of these fish is a wading bird that hunts by sight. Most of the fish are light sandy brown, but about 10% are mottled. The color pattern is heritable. A construction company dumps a load of gravel in the bottom of the lake, giving it a mottled appearance. Which of these statements presents the most accurate prediction?

a. As the sand-colored fish are eaten, more will be produced to keep their frequency at 90%.
b. There is no way to guess the result, because evolution occurs at random.
c. The proportion of mottled fish will increase over time.
d. According to the Hardy-Weinberg equilibrium, the ratios will not change.

A predator can be define as organism which makes the other organisms to die to obtain them as food. A prey is the living being which is typically inferior and killed by the predator. Adaptation is a change in the physiology, morphology and genetic make up of the organism which makes it suitable for survival in the unfavorable environment. Natural selection is the differential survival and reproduction of the organisms which exhibit better traits over the others.

According to the given situation, the population of the mottled fish is likely to increase due to natural selection. As the mottled fish color pattern match with that of the mottled background of the bottom of the lake. This will help the mottled fishes to camouflage the predator wading birds. These mottled fishes will remain undetected from the predator wading birds. The trait of mottled pattern will be adapted by the light sandy brown fishes and the trait will be passed on the next generation as well. Hence, the proposition of the mottled fish will increase.