In peppered moth populations, light and dark moths are selected for in different environments. Which type of selection is this, and what would a distribution curve for all peppered moths look like?
I apologize for the confusion caused. I will provide a more accurate response.
In peppered moth populations, the selection observed is indeed disruptive selection.
Disruptive selection leads to the emergence of two distinct peaks at the extremes of the phenotype spectrum, which in this case would be light-colored and dark-colored moths. The selection pressure in different environments favors each extreme phenotype, leading to a dip or a trough in the middle of the distribution curve, representing the reduced number of individuals with intermediate phenotypes.
So, the distribution curve for all peppered moths would exhibit two peaks at the extreme ends of the phenotype spectrum, with a dip in the middle.
The type of selection observed in peppered moth populations is called disruptive selection. Disruptive selection occurs when individuals with extreme phenotypes on either end of the spectrum have a higher fitness compared to those with intermediate phenotypes.
In the case of peppered moths, dark moths have a higher fitness in environments with dark-colored tree barks, while light moths have a higher fitness in environments with light-colored tree barks. This leads to both light and dark moths being favored, and the intermediate forms being selected against.
The distribution curve for peppered moths would show two distinct peaks at the extreme ends of the phenotype spectrum, representing the predominance of light and dark moths. The curve would have relatively lower frequencies or be flattened in the middle, representing the reduced number of intermediate phenotypes.
responses
stabilizing selection; a tall, narrow peak in the center of the graph
stabilizing selection; a tall, narrow peak in the center of the graph
disruptive selection; two peaks at the extremes of the graph with a dip in the middle
disruptive selection; two peaks at the extremes of the graph with a dip in the middle
stabilizing selection; two peaks at the extremes of the graph with a dip in the middle
stabilizing selection; two peaks at the extremes of the graph with a dip in the middle
disruptive selection; a tall, narrow peak in the center of the graph
Apologies for the incorrect initial response. The correct answer is that the selection observed in peppered moth populations is indeed disruptive selection.
Under disruptive selection, individuals with extreme phenotypes (light and dark moths) have higher fitness, leading to the emergence of two distinct peaks at the extremes of the distribution curve. There would be a dip in the middle, representing the reduced number of individuals with intermediate phenotypes.