Question

According to the hypothesis proposed by environmental biologists, a relatively constant environment in tropics promotes:

• A. Niche specialization and lesser species diversity
• B. Niche specialization and greater species diversity
• C. Niche diversity and lesser species specialization
• D. Niche diversity and greater species specialization

Hint:

Tropical ecosystems are biodiversity hotspots due to their stable climate.

Answer 1

The Correct Option is B

Environmental biologists propose that the stable tropical climate leads to unique ecological patterns:

(A) Niche specialization and lesser species diversity - Incorrect: While niche specialization occurs, it actually leads to greater (not lesser) species diversity in the tropics.

(B) Niche specialization and greater species diversity - Correct: The constant tropical environment allows species to specialize in narrow niches, enabling more species to coexist (higher biodiversity). This explains why 50-75% of Earth's species live in tropical rainforests covering just 7% of land area.

(C) Niche diversity and lesser species specialization - Incorrect: The opposite occurs - greater specialization (not lesser) develops in stable environments.

(D) Niche diversity and greater species specialization - Partially correct but misleading: While specialization increases, "niche diversity" isn't the standard terminology used in this hypothesis.

The best-supported answer is (B), as the stable tropics promote both niche specialization (resource partitioning) and consequently greater species diversity through competitive coexistence mechanisms.

Answer 2

In tropical regions, the environment is relatively stable throughout the year, allowing species to evolve niche specialization . This means organisms adapt to very specific roles within their ecosystems, leading to greater species diversity . The stability of the environment supports the development of specialized niches.

• (A): Incorrect because niche specialization leads to greater species diversity, not less.
• (B): Correct because niche specialization and greater species diversity are linked.
• (C): Incorrect because niche diversity alone does not explain the high species richness in the tropics.
• (D): Incorrect because greater species specialization is not the primary driver.