Question

Environment: Clean Forest Phenotype Frequency Allele Frequency Genotype Frequency Environment: Polluted Forest Moths Released G1 G2 G3 G4 G5 Typica 490 186 148 114 77 40 Carbonaria 510 367 617 763 974 1331 Total 1000 553 765 877 1051 1371 Phenotype Frequency Color Initial Frequency Frequency G5 Typica Light 0.49 0.03 Carbonaria Dark 0.51 0.97 Allele Frequency Allele Initial Allele Frequency G5 Allele Frequency q d 0.70 0 p D 0.30 Genotype Frequency Moths Genotype Color Moths Released Initial Frequency Frequency G5 Number of Moths G5 q2 Typica dd Light 490 0.49 2pq Carbonaria Dd Dark 420 0.42 p2 Carbonaria DD Dark 90 0.09

Answer 1

In evolution and biology, directional selection leads to changes in a population's phenotype frequencies, as demonstrated by the historical example of the peppered moth, where dark-colored moths became more prevalent due to better camouflage after environmental changes caused by pollution.

Step-by-step explanation:

The scenario described involves a population of organisms, like beetles or moths, undergoing directional selection as a result of environmental changes due to pollution. This type of selection causes certain phenotypes, such as darker coloration, to become more prevalent because they provide a survival advantage in the altered environment. As the environment becomes darker due to pollution, dark-colored individuals are better camouflaged, leading to an increased frequency of their phenotype within the population.

Historically, the peppered moth serves as an example of this process. Originally light-colored moths were common because they were camouflaged against light tree trunks. However, as the Industrial Revolution caused soot to darken tree trunks, the frequency of darker-colored moths increased due to their improved camouflage and consequent increased survival rate. This phenomenon illustrates how allele frequencies in a population can shift due to changes in the environment, a process fundamental to evolutionary biology.