The Peppered Moth Provides a Well-Known Example of Natural Selection

question 8

Multiple Choice

The peppered moth provides a well-known example of natural selection. The light-colored form of the moth was predominant in England before the Industrial Revolution. In the mid-nineteenth century, a dark-colored form appeared. The difference is produced by a dominant allele of one gene. The dark- and light-colored forms readily interbreed with each other. By about 1900, approximately 90 percent of the moths around industrial areas were dark colored, whereas light-colored moths were still abundant elsewhere. Apparently, birds could readily find the light moths against the soot-darkened background in industrial areas and, therefore, were eating more light moths. Recently, use of cleaner fuels has greatly reduced soot in the landscape, and the dark-colored moths have been disappearing. Should the two forms of moths be considered separate species?

• A) Yes, because natural selection has affected the frequency of the two different forms.
• B) Yes, because they have completely different coloration.
• C) Yes, because they are reproductively isolated based on habitat.
• D) Yes, because they have completely different coloration and natural selection has affected the frequency of the two different forms.
• E) No.

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Definitions:

Encoding

The process of converting thoughts into communicable messages, often through selecting specific words or nonverbal methods.

Intrapersonal Communication

The process of internal dialogue or conversation within oneself, which influences one's thoughts, feelings, and behaviors.

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The act of living together in a romantic relationship without being married.