In a Previous Chapter You Read About "Keystone Species

question 28

Multiple Choice

In a previous chapter you read about "keystone species." How do the prairie dogs in this story meet the definition of a keystone species?

• A) Their burrows loosened the soil and served as homes for other species; they helped with nutrient recycling. They helped water infiltrate into the soil and kept soil loose for grass roots. When they were removed, the system deteriorated.
• B) The availability of prairie dogs kept the predators in check; when they were removed, the predator populations grew dramatically. Prairie dogs also kept the soil aerated and compact.
• C) When the prairie dogs were removed, the cattle declined, which meets the definition of a keystone species.
• D) They don't meet the definition of a keystone species; the system did fine without them. The predators switched to preying on cattle, and the grasses did better in the compact soil.
• E) Their burrows caused cattle to break their legs and die. This made them directly responsible for the welfare of another species, which meets the definition of a keystone species.

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Definitions:

Insurance

A contract by which the insurer promises to reimburse the insured or a beneficiary in the event that the insured is injured, dies, or sustains damage to property as a result of particular, stated contingencies.

Insurable Interest

A requirement in insurance policies that the policyholder must have a financial interest in the insured item or person that would cause financial loss if damaged or lost.

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A company that specializes in producing electrical or mechanical devices intended to perform certain tasks, typically domestic ones.

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Retail outlets offering goods for sale at lower prices due to immediate payment instead of credit purchase.