Since the Pleistocene Ice Age, Deserts Have Been Gradually Forming

question 62

Multiple Choice

Since the Pleistocene ice age, deserts have been gradually forming in the southwestern United States. As the original lakes and rivers of this area shrank into isolated streams, ponds, and springs, the fishes living in them developed a strong potential for

• A) hybrid inviability.
• B) mechanical incompatibility.
• C) hybridization.
• D) temporal isolation.
• E) speciation.

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Definitions:

Public Good

A product or service that is non-excludable and non-rivalrous, meaning its consumption by one individual does not reduce its availability to others.

Collective Willingness

The aggregated preference or desire of a group of individuals to support or buy into a particular idea, policy, or product.

Marginal Cost

The boost in complete costs associated with creating one more unit of a product or service.

Private Good

A product that is excludable and rival in consumption, meaning its use is limited to the purchaser and it cannot be shared without diminishing availability to others.