If in One Population of Pupfish All of the Individuals

question 49

Multiple Choice

If in one population of pupfish all of the individuals have a blood pigment that is extraordinarily effective at carrying oxygen, but this trait is not seen in any of the other populations, what likely happened?

• A) Because oxygen was low where these pupfish lived, a new allele for an effective blood pigment arose.
• B) This population was lucky to have an individual with a random mutation for an effective blood pigment, and the frequency of this allele was increased in subsequent generations through natural selection.
• C) The ancestral population probably had this type of blood pigment, but it was lost through genetic drift in the other 29 populations.
• D) The other populations did not need this pigment, so they did not evolve it.

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Definitions:

Internal Causes

Factors within a person, such as beliefs, desires, or personality traits, that explain their behaviors and decisions.

Law of Contingent Reinforcement

The Law of Contingent Reinforcement posits that the effectiveness of reinforcement (such as rewards or punishments) is dependent on its being administered contingent upon the occurrence of the behavior it is meant to encourage or discourage.

Desirable Behavior

Actions or conduct that are viewed positively and encouraged within a particular social or organizational culture.

Classical Conditioning

A learning process that occurs when two stimuli are repeatedly paired; a response that is at first elicited by the second stimulus is eventually elicited by the first stimulus alone.