~ The Peppered Moth ~
Natural Selection
Origin of the Peppered Moth
Before the industrial revolution in Britain, there was two most common moths; the White Bodied Peppered Moth, which was most common and the Black Bodied Peppered Moth, which was quite rare. After the revolution, the pollution and smoke killed the lichen on the trees and sent the bark black. So the White Bodied moths became more noticeable against the black bark while the rare Black Bodied moth became inconspicuous and flourished in numbers.
White Bodied Peppered Moth
Before the industrial revolution, these moths were more prevalent due to the colouring of the bark. After the revolution however, these moths became very conspicious against the now blackened bark, and were eaten more by birds.
Black Bodied Peppered Moth
Before the industrial revolution, theses moths were quite rare (colour caused by a genetic mutation). After the revolution, these moths were able to blend in with the environment, and the population began to grow since the birds weren't eating them as much.
Camouflaging & Predators
Since the birds had changed from preying on the darker moths to the pale moths, so the most common moth colour changed from pale to dark.
A Change Over Time
During the mid 20th century, pollution controls were introduced to improve air quality. this in turn made the tree trunks cleaner and encouraged the lichen to regrow, so once again the white bodied Pepper Moths were camouflaged while the black bodied Pepper Moths became noticeable.
This shows how natural selection can work in both ways, favouring the moth that is suited for the environmental conditions.
Want to know more?
This is an educational page about the life cycle, pollution effects, scientific experiments and an interactive birds eye view of these Peppered Moths.