Question
natural selection and evolution example
Answers
Answered by
GPT-4o mini
Certainly! One classic example of natural selection and evolution is observed in the peppered moth (Biston betularia) in England.
### Background
Before the Industrial Revolution, most peppered moths were light-colored, which helped them blend in with the light-colored lichen and tree bark in their environment. A smaller number of these moths had a dark coloration due to a genetic mutation.
### The Process of Natural Selection
1. **Environmental Change**: During the Industrial Revolution, pollution from factories darkened the tree bark and killed off the lichen, creating an environment that favored darker-colored moths.
2. **Variation**: The population of peppered moths exhibited variation in coloration (light and dark).
3. **Survival Advantage**: Dark-colored moths had a camouflage advantage in the polluted environment, making it harder for predatory birds to spot them compared to their lighter counterparts.
4. **Reproduction**: As a result, dark moths were more likely to survive, reproduce, and pass on their genes to the next generation.
5. **Shifts in Population**: Over time, the frequency of dark-colored moths in the population increased. By the late 20th century, dark-colored peppered moths became much more common than light-colored ones in industrial areas.
### Conclusion
This example of the peppered moth illustrates how natural selection can lead to changes in the traits of a population over time in response to environmental pressures. It also demonstrates how evolution can occur as advantageous traits become more common in a population, driven by the differential survival and reproduction of individuals with those traits.
As air quality improved and pollution levels decreased in the late 20th century, the light-colored moths began to re-emerge, showcasing a dynamic process of evolution in response to changing environmental conditions.
### Background
Before the Industrial Revolution, most peppered moths were light-colored, which helped them blend in with the light-colored lichen and tree bark in their environment. A smaller number of these moths had a dark coloration due to a genetic mutation.
### The Process of Natural Selection
1. **Environmental Change**: During the Industrial Revolution, pollution from factories darkened the tree bark and killed off the lichen, creating an environment that favored darker-colored moths.
2. **Variation**: The population of peppered moths exhibited variation in coloration (light and dark).
3. **Survival Advantage**: Dark-colored moths had a camouflage advantage in the polluted environment, making it harder for predatory birds to spot them compared to their lighter counterparts.
4. **Reproduction**: As a result, dark moths were more likely to survive, reproduce, and pass on their genes to the next generation.
5. **Shifts in Population**: Over time, the frequency of dark-colored moths in the population increased. By the late 20th century, dark-colored peppered moths became much more common than light-colored ones in industrial areas.
### Conclusion
This example of the peppered moth illustrates how natural selection can lead to changes in the traits of a population over time in response to environmental pressures. It also demonstrates how evolution can occur as advantageous traits become more common in a population, driven by the differential survival and reproduction of individuals with those traits.
As air quality improved and pollution levels decreased in the late 20th century, the light-colored moths began to re-emerge, showcasing a dynamic process of evolution in response to changing environmental conditions.