NATURAL HISTORY MUSEUM, LONDON / SCIENCE PHOTO LIBRARY NATURAL HISTORY MUSEUM, LONDON / SCIENCE PHOTO LIBRARY
Two peppered moths (Biston betularia). Two forms of this moth occur, a pale form (top) and a dark form (bottom). The dark form became dominant in parts of northern England after the industrial revolution, when trees were covered by black soot. This phenomenon is known as industrial melanism, and is an example of natural selection.
Model release not required. Property release not available.