Biston betularia

Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Lepidoptera
Family: Geometridae
Genus: Biston
Species: B. betularia
Common name: Peppered Moth

Commonly called the peppered moth, this is one of the most famous examples in biology because of its role in studies of natural selection and industrial melanism. This is one of the most famous examples in biology because of its role in studies of natural selection and industrial melanism. Typically the moth has pale whitish wings with black speckling, giving a peppered appearance which provides camouflage against lichen-covered tree bark. However during the industrial revolution in Britain a Melanic form which was nearly all black aincreased dramatically in polluted industrial areas where tree bark was blackened by soot, and the light form remained common in rural, unpolluted areas. Following Clean Air Acts the light form has become more dominate, though intermediate forms sometimes occur, with varying amounts of dark pigmentation. This shift was a textbook example of natural selection: predation by birds favoured whichever form was best camouflaged. The caterpillars are twig-like appearance, and highly cryptic (resembling sticks). Feeding on many deciduous trees and shrubs, including birch, oak, willow, and hazel, they vary in colouration (brown, green, gray) to blend with host plants.