The Most Plausible Hypothesis to Explain Why Species Richness Is

question 55

Multiple Choice

The most plausible hypothesis to explain why species richness is higher in tropical than in temperate regions is that

• A) tropical communities are younger.
• B) tropical regions generally have more available water and higher levels of solar radiation.
• C) higher temperatures cause more rapid speciation.
• D) diversity increases as evapotranspiration decreases.
• E) tropical regions have very high rates of immigration and very low rates of extinction.

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Definitions:

Control Group

Subjects in an experiment who do not receive the special treatment given to the experimental group.

Special Treatment

Preferential or distinct consideration given to an individual or group, often based on specific needs, status, or criteria.

Correlation

The extent to which two variables are related to each other.

Dependent Variable

In research, the variable that is being tested and measured to see if it is affected by changes in another variable.