The order lepidoptera we have is species of butterfly. We have the white and the black butterflies which freely interbreed and both live in an industrialized area. The white butterflies were initially more adaptive to the region than the black butterflies. When the region was not industrialized the population of the white butterflies was high compared top that of the black butterflies as the white butterflies were camouflaged by the environment and when the prey attacked would be able to see the black butterflies and not the white butterflies as they will be camouflaged by the surroundings. The population of the black butterflies decreased due to their frequent attacks by the prey and that of the white butterflies increased as they were spared by the prey that did not even notice their presence and only kept attacking the black butterflies leading to their decrease in population. The industries were introduced in the area and the emission of the soot in the environment started. The vegetation around the area started to turn its colour to black and with time all the vegetation was black and the black butterflies became more adaptive to the environment and the white were not adaptive to the environment (Williams, 1996).
The prey now shifted to the white butterflies who this time round were not favored by the surrounding. The populations of the black butterflies increased drastically and were more in the vegetation compared to the white butterflies that had been the survival of the prey (Williams, 1996).
References
George Williams (1996), Adaptation and Natural selection Princeton University Press.