A Study by Charles and Mary Brown Has Documented a Reduction

question 41

Multiple Choice

A study by Charles and Mary Brown has documented a reduction in the wing length of cliff swallows that live near busy roadways; the study proposes that the need to avoid being hit by cars is the evolutionary driving force for the change.How would you evaluate this hypothesis if wing length had also shortened in cliff swallow populations that live in the desert Southwest where traffic is virtually nonexistent?

• A) The hypothesis would still be valid. Natural selection is driven by local conditions; the two populations are probably evolving independently and they have coincidentally acquired the same characteristics.
• B) The hypothesis would raise some doubts; perhaps aerial predators or another factor yet to be identified are creating the necessity for better flying skills in both populations.
• C) The hypothesis would not be valid, because the probability of the same wing length mutation arising in geographically distinct populations is extremely low.
• D) The hypothesis would not be valid; if the need to avoid vehicular collisions is driving natural selection, then no evolution should be occurring in the population that lives in the traffic-free environment.

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Definitions:

Racial Profiling

The discriminatory practice by law enforcement officials of targeting individuals for suspicion of crime based on the individual's race, ethnicity, religion, or national origin.

Stereotyping

Simplifying complex individuals to generalized traits or categories based on their group membership, ignoring personal differences.

Attribution

An assignment of a cause to explain one’s own or another person’s behavior.

Situational Attribution

The process of explaining someone's behavior based on external factors or the context of the situation rather than on internal characteristics.