Principle #1: Genetic Variation In the clownfish population there are both black and orange but the orange clownfish population is decreasing because they are being eaten by the great white sharks while the black population is surviving because they are able to blend in with dark surroundings and hide away from the great white sharks.
Principle #2: Overpopulation & Selective Pressures Both clownfish pass on their traits to their offspring's but when the orange clownfish pass on their traits to their offspring than there offspring may not live as long because they are very obvious to see for the great white sharks while when the black clownfish pass on their traits their offspring will most likely live longer because they are able to blend in.
Principle #3: Differential Survival & Reproduction The black clownfish that inherits the beneficial traits from their parents are able survive the great white sharks. Since they survive, they live long enough to reproduce.
Principle #4: Changes in the Gene Pool Throughout the generations there will be an increase in the number and population of the black clownfish but there will be a decrease in the number and population of the orange clownfish.