The Next Few Questions Refer to the Following Description

question 4

Multiple Choice

The next few questions refer to the following description.
In the ocean, on either side of the Isthmus of Panama, are 30 species of snapping shrimp; some are shallow-water species, others are adapted to deep water. There are 15 species on the Pacific side and 15 different species on the Atlantic side. The Isthmus of Panama started rising about 10 million years ago.
In the following figure, the isthmus separates the Pacific Ocean on the left (side A) from the Atlantic Ocean on the right (side B) . The seawater on either side of the isthmus is separated into five depth habitats (1-5) , with 1 being the shallowest.

-Which factor is most important for explaining why there are equal numbers of snapping shrimp species on either side of the isthmus?

• A) the relative shortness of time they have been separated
• B) the depth of the ocean
• C) the number of actual depth habitats between the surface and the sea floor
• D) the elevation of the isthmus above sea level
• E) the depth of the canal

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Definitions:

Short-run Phillips Curve

A graphical representation showing the inverse relationship between the rate of inflation and the rate of unemployment in an economy over a short period.

Favorable Supply Shock

An unexpected event that increases the availability of a good or service, thus lowering its price and benefiting consumers.

Inflation

The measure of how quickly the general pricing for products and services advances, decreasing monetary purchasing power.

Unemployment Rate

The ratio of individuals without employment, yet are actively pursuing job opportunities in the labor force.