The Most Plausible Hypothesis to Explain Why Species Richness Is

question 51

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

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Definitions:

Thymus Gland

An organ located in the chest, which plays a vital role in the development and maturation of T-cells, essential for the immune response.

Reticular Fibers

Fine, branching fibers forming networks in various tissues and supporting cells in organs like the spleen and lymph nodes.

Medulla

The innermost part of an organ or structure, often referring to the medulla oblongata in the brain, which controls vital functions such as breathing and heart rate.

Lymphocytes

White blood cells that play a crucial role in the immune system, responsible for producing antibodies and other substances to fight infections.