Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R. Assertion A: The centers of the greatest biodiversity, the mega-biodiversity regions of the world, tend to be in the tropics.
Reason R: Over long geological times, the tropical areas have had a more stable climate, never been glaciated, therefore, local species continued to thrive and live there itself.
Choose the correct answer from the options given below:

Correct option is A

The correct answer is (a) Both A and R are true and R is the correct explanation of A.
· Assertion A is true: The tropics are known as the centers of the greatest biodiversity. Tropical regions such as the Amazon Rainforest, Central Africa, and Southeast Asia are rich in species diversity, making them mega-biodiversity regions.
· Reason R is also true: Tropical regions have experienced climatic stability over long geological timescales. They were not significantly affected by the glaciations that impacted temperate and polar regions. This stability allowed species to thrive, adapt, and diversify over time, contributing to the high levels of biodiversity.
Since the stable climate in tropical regions explains why they support the greatest biodiversity, R is the correct explanation of A.
Information Booster 1. Tropical Biodiversity:
· High Biodiversity: Tropical regions support more species compared to temperate and polar regions.
· Mega-Biodiversity Regions: Examples include the Amazon Rainforest, Congo Basin, and Southeast Asian rainforests.
2. Climatic Stability:
· Over millions of years, the tropics have maintained stable temperatures and climates.
· Lack of glaciation allowed continuous evolution and adaptation of species.
3. Glaciation Effects:
· During the Ice Ages, temperate and polar regions were covered in ice, leading to species extinction or migration.
· The tropics remained relatively unaffected, preserving diverse ecosystems.
4. Evolutionary Factors:
· The consistent environment in the tropics allowed for niche specialization and high speciation rates.
Additional Knowledge · Biodiversity Hotspots:
· Areas with exceptionally high levels of biodiversity and endemism. Examples: Amazon, Madagascar, and the Indo-Burma region.
· Factors Supporting Tropical Biodiversity:
· Stable Climate: Few drastic changes over geological time.
· High Productivity: Consistent sunlight and rainfall support lush vegetation.
· Complex Habitats: Provide various niches for different species.