In England, it was observed that Biston betularia (peppered moth) showed cryptic colouration with two phenotypes, white (light winged) moths which outnumbered dark black winged moths. After industrialisation the falling smoke particles darkened the background of tree trunk. Against a dark background, the light coloured moths became conspicuous and were picked up by the predator birds the dark coloured moths outnumbered the light coloured moths and they had a much better chance of survival under the new conditions created by industrial pollution. Before industrialisation sel in, thick growth of almost white-coloured the tree. In that background the white winged moth survived but coloured moth were picked up by predators. Thus. industrial melanism demonstrates the action of natural selection
