Assertion : Tropical regions have got a long evolutionary time for species diversification as compared to temperate regions.
Reason : Temperate regions have undergone frequent glaciations in the past whereas tropical regions have remained relatively undisturbed for millions of years.

Tropical regions have greater biodiversity as compared to temperate regions due to :-

What is so special about tropics that might account for their greater biological diversity? a. Unlike temperate regions subjected to frequent glaciations in the past, tropical latitudes have remained relatively undisturbed for millions of years and thus, had a long evolutionary time for species diversification. b. Temperate environments, unlike tropical ones, are less seasonal, relatively more constant and predictable. Such constant environments promote niche specialization and lead to a greater species diversity. c. There is more solar energy available in the tropics, which contributes to higher productivity, this in turn might contribute indirectly to greater diversity.

What is so special about tropics that might account for their greater biological diversity? a. Unlike temperate regions subjected to frequent glaciations in the past, tropical latitudes have remained relatively undisturbed for millions of years and thus, had a long evolutionary time for species diversification. b. Temperate environments, unlike tropical ones, are less seasonal, relatively more constant and predictable. Such constant environments promote niche specialization and lead to a greater species diversity. c. There is more solar energy available in the tropics, which contributes to higher productivity, this in turn might contribute indirectly to greater diversity.

The tropics have more diversity of vascular plants as compared to the temperature regions because of

The temperate regions show a lower value of primary productivity as compared to tropical regions.

Assertion : Lichens are a pioneer community in the temperate region. Reason : Blue-green algae grow as the pioneer community in the tropical region.