Industrial Melanism and Natural Selection

Industrial melanism is an example of natural selection in action. This phenomenon refers to the darkening of populations of organisms over time in response to environmental changes, particularly pollution. Here's how industrial melanism demonstrates the concept of natural selection:

Mutation as the Initial Cause

- Initially, a mutation occurs in the population that results in some individuals having a darker coloration than others.
- This mutation is a random event that introduces genetic variation into the population.

Natural Selection in Action

- In an industrialized environment where there is pollution, darker individuals have a survival advantage over lighter individuals.
- The darker coloration provides better camouflage against pollution-darkened backgrounds, making these individuals less likely to be preyed upon.
- As a result, darker individuals are more likely to survive and reproduce, passing on their genes for dark coloration to the next generation.
- Over time, the frequency of the dark coloration trait increases in the population, while the lighter individuals become less common.

Significance in Evolution

- Industrial melanism provides a clear example of how natural selection can drive evolutionary change in response to environmental pressures.
- It illustrates how genetic variation, mutation, and selective pressures can lead to adaptations that enhance the survival and reproductive success of individuals in a changing environment.
- This phenomenon has been extensively studied and serves as a classic example of evolution in action.