Question
Peppered moths are normally white with black speckles across the wings, giving it its name. This patterning makes it well camouflaged against lichen-covered tree trunks when it rests on them during the day.
There is also a naturally occurring genetic mutation, which causes some moths to have almost black wings. These black forms (called 'melanic') are not as well camouflaged on the lichen as normal 'peppered' forms, so they are more likely to be eaten by birds and other predators. This means that fewer black forms survive to breed, so they are less common in the population than the paler peppered forms. This is the normal situation observed in the countryside of Britain and Ireland.
However, in the nineteenth century it was noticed that in towns and cities it was actually the black form of the moth that was more common than the pale peppered form. Industrialization and domestic coal fires had caused sooty air pollution, which had killed off lichens and blackened urban tree trunks and walls. So, it was now the pale form of the moth that was more obvious to predators, while the melanic form was better camouflaged and more likely to survive and produce offspring. As a result, over successive generations, the black moths came to outnumber the pale forms in our towns and cities.
In the mid-twentieth century, controls were introduced to reduce air pollution and, as the air quality improved, tree trunks became cleaner and lichen growth increased. Once again, the normal pale Peppered Moths were camouflaged and the black forms were more noticeable. Now the situation in urban areas has again become the same as in the countryside, with normal pale Peppered Moths being far more common than the black forms. So, natural selection has been seen to work in both directions, always favoring the moth that is best suited to the environmental conditions. The same thing has been observed throughout Europe and the USA.
Write a CER (Claim-Evidence-Reasoning) statement concerning the following prompt:
Evaluate the claim that the peppered moth example is strong evidence for evolution by natural selection.
There is also a naturally occurring genetic mutation, which causes some moths to have almost black wings. These black forms (called 'melanic') are not as well camouflaged on the lichen as normal 'peppered' forms, so they are more likely to be eaten by birds and other predators. This means that fewer black forms survive to breed, so they are less common in the population than the paler peppered forms. This is the normal situation observed in the countryside of Britain and Ireland.
However, in the nineteenth century it was noticed that in towns and cities it was actually the black form of the moth that was more common than the pale peppered form. Industrialization and domestic coal fires had caused sooty air pollution, which had killed off lichens and blackened urban tree trunks and walls. So, it was now the pale form of the moth that was more obvious to predators, while the melanic form was better camouflaged and more likely to survive and produce offspring. As a result, over successive generations, the black moths came to outnumber the pale forms in our towns and cities.
In the mid-twentieth century, controls were introduced to reduce air pollution and, as the air quality improved, tree trunks became cleaner and lichen growth increased. Once again, the normal pale Peppered Moths were camouflaged and the black forms were more noticeable. Now the situation in urban areas has again become the same as in the countryside, with normal pale Peppered Moths being far more common than the black forms. So, natural selection has been seen to work in both directions, always favoring the moth that is best suited to the environmental conditions. The same thing has been observed throughout Europe and the USA.
Write a CER (Claim-Evidence-Reasoning) statement concerning the following prompt:
Evaluate the claim that the peppered moth example is strong evidence for evolution by natural selection.
Answers
GPT-4o mini
**Claim:** The example of the peppered moth is strong evidence for evolution by natural selection.
**Evidence:** The observed changes in the populations of the peppered moth demonstrate adaptation to changing environmental conditions. In the pre-industrial era, the pale peppered moth was more common due to its camouflage against lichen-covered tree trunks, which provided a survival advantage against bird predation. However, during the industrial revolution, increased pollution blackened tree surfaces, leading to a dramatic rise in the population of melanic (black) moths, as they became better camouflaged and, consequently, faced lower predation. The reversal of this trend in the mid-twentieth century, when pollution controls improved air quality and allowed lichens to thrive again, resulted in a resurgence of pale peppered moths. The observable shifts in moth coloration in response to environmental changes closely mirror the principles of natural selection, with the phenotypes’ survival rates directly influencing their reproductive success over generations.
**Reasoning:** This case illustrates natural selection in action, as the varying camouflage effectiveness of the moths directly correlates with their environments and predator interactions. The change in dominant color phases in response to industrial pollution provides a clear example of how external environmental pressures can drive evolutionary change. The predictable cyclical pattern of survival and reproduction based on environmental suitability underscores the mechanism of natural selection. Therefore, the case of the peppered moth not only supports the theory of evolution but also exemplifies how species adapt over time to their changing ecosystems, making it strong evidence for evolution by natural selection.
**Evidence:** The observed changes in the populations of the peppered moth demonstrate adaptation to changing environmental conditions. In the pre-industrial era, the pale peppered moth was more common due to its camouflage against lichen-covered tree trunks, which provided a survival advantage against bird predation. However, during the industrial revolution, increased pollution blackened tree surfaces, leading to a dramatic rise in the population of melanic (black) moths, as they became better camouflaged and, consequently, faced lower predation. The reversal of this trend in the mid-twentieth century, when pollution controls improved air quality and allowed lichens to thrive again, resulted in a resurgence of pale peppered moths. The observable shifts in moth coloration in response to environmental changes closely mirror the principles of natural selection, with the phenotypes’ survival rates directly influencing their reproductive success over generations.
**Reasoning:** This case illustrates natural selection in action, as the varying camouflage effectiveness of the moths directly correlates with their environments and predator interactions. The change in dominant color phases in response to industrial pollution provides a clear example of how external environmental pressures can drive evolutionary change. The predictable cyclical pattern of survival and reproduction based on environmental suitability underscores the mechanism of natural selection. Therefore, the case of the peppered moth not only supports the theory of evolution but also exemplifies how species adapt over time to their changing ecosystems, making it strong evidence for evolution by natural selection.