The British Peppered Moth Evolution
The steps of natural selection can be explained using the British Peppered Moth evolution. The British Peppered Moth evolution is the most well-known form of natural selection. It is a famous, yet amazing story that is easy to understand, illustrate and makes an intuitive sense.
What is it? Peppered moths are normally white with black speckles across the wings, giving it its name. This patterning allows them to camouflage very well against lichen-covered tree trunks when it rests on them during the day. They are a temperate (fairly related to) species of the night flying moths. |
Evolution
During the nineteenth century, the peppered moths were in a darker, black form, especially around the towns and cities. Industrialization during the nineteenth century is the main reason why peppered moths were completely black. The domestic coal fires caused heavily polluted air to spread killing off lichens, blackening them and blackened urban trees. The pale form of the moth would eventually become easy targets and obvious to predators. Their species within that population of peppered moths would die out and have a very small percentage left. The black form of moths however, were better camouflaged and able to live longer and produce offspring. As a result, the back forms outnumbered the pale. Since moths are short-lived, this evolution by natural selection happened quite quickly. For example, the first black Peppered Moth was recorded in Manchester in 1848 and by 1895 98% of Peppered Moths in the city were black. |