The evolution of the peppered moth is an evolutionary instance of directional colour change in the moth population as a consequence of air pollution during the Industrial Revolution. The frequency of dark-coloured moths increased at that time, an example of industrial melanism. Later, when pollution was reduced, the light-coloured form again predominated. Industrial melanism in the peppered moth was an early test of Charles Darwin's natural selection in action, and it remains a classic example in the teaching of evolution. In 1978, Sewall Wright described it as "the clearest case in which a conspicuous evolutionary process has actually been observed."
Biston betularia f. typica, the white-bodied peppered moth.
Biston betularia f. carbonaria, the black-bodied peppered moth.
Typica and carbonaria morphs on the same tree. The light-coloured typica (below the bark's scar) is nearly invisible on this pollution-free tree, camouflaging it from predators.
Creationists have disputed the occurrence or significance of the melanic carbonaria morph's increase in frequency.
The peppered moth is a temperate species of night-flying moth. It is mostly found in the northern hemisphere in places like Asia, Europe and North America. Peppered moth evolution is an example of population genetics and natural selection.
Image: Biston betularia male
Image: Peppered moth (Biston betularia) female
Biston betularia ♂
Biston betularia ♂ △