A Biologist Studied a Population of Squirrels for 15 Years

question 27

Multiple Choice

A biologist studied a population of squirrels for 15 years. During that time, the population was never fewer than 30 squirrels and never more than 45. Her data showed that over half of the squirrels born did not survive to reproduce, because of both competition for food and predation. In a single generation, 90% of the squirrels that were born lived to reproduce, and the population increased to 80. Which inference(s) about this population might be true?

• A) The amount of available food may have increased.
• B) The parental generation of squirrels developed better eyesight due to improved diet; the subsequent squirrel generation inherited better eyesight.
• C) The number of predators that prey upon squirrels may have decreased.
• D) A and C could be true.
• E) A, B, and C could be true.

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Definitions:

Placid

Describes a calm, peaceful, or tranquil state or demeanor.

New York Longitudinal Study

A research project that began in the 1950s tracking the temperamental characteristics of infants and how these traits relate to personality development.

Temperamental Category

A classification in psychology that describes inherent personality traits and behavior tendencies that are observable in infancy and assumed to be biologically based.

Mixed Temperament

A combination of multiple temperament traits in an individual, showing behavioral characteristics that are not dominated by a single temperament type.