Absence of limbs in snakes
Melanisation in peppered moth
Lack of pigment in cave-dwelling animals
Presence of webbed toes in aquatic birds
Industrial melanism, observed in moths is an example of natural selection, proposed by Darwin. In this scenario, the moths living industrial areas, developed melanin pigments to match their body to the soot-covered surroundings. The phenomenon provides an excellent example of the operation of selection in natural conditions. It is not the example of acquired characters proposed by Lamarck. In caves, due to the absence of light, the body of the animal lacks pigmentation, e.g., Proteus anguinus. In pythons and related snakes rudimentary pelvic girdle and traces of hind-limb are present. They form small-clawed projections externally, but internally there are vestiges of an ilium, femur, tibia and a claw. In aquatic birds and flying frog, the feet are webbed which sustain it in the prolonged leaps to which it is adapted. So, the correct answer is 'Melanisation in peppered moth'