Assertion (A): | There is a steady increase in species richness from the arctic to the tropics. |
Reason (R): | Seasonal variation is substantially more in tropics than in arctics. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | Both (A) and (R) are False. |
Regarding the gradients of biodiversity:
I: | As we move from poles to the equator, broadly speaking, biodiversity decreases. |
II: | There is an increase in species diversity from lower to higher altitudes. |
1. Only I is correct
2. Only II is correct
3. Both I and II are correct
4. Both I and II are incorrect
The greatest biodiversity on the earth is found in:
1. | African grasslands |
2. | Amazonian rain forest in South America |
3. | Western Ghats in India |
4. | Nile delta in Egypt |
Which of the following is not a reason that accounts for greater biodiversity of tropics?
1. | availability of more solar energy |
2. | more niche specialization |
3. | more time for species diversification |
4. | large seasonal variations in environmental factors |
Consider the two statements:
I: | Species diversity seen in tropical areas is much lower than that seen in temperate areas. |
II: | Temperate areas, unlike tropical areas are less seasonal, more constant and promote niche specialization. |
1. Both I and II are correct and II explains I.
2. Both I and II are correct but II does not explain I.
3. I is correct but II is incorrect.
4. Both I and II are incorrect.
The name of Alexander von Humboldt is associated with the concept of:
1. | Increased species diversity in stable communities |
2. | Parallelism between evolution and ecological succession |
3. | Resource-partitioning to avoid competition |
4. | Species-Area relationship |
I. | Within a region, species richness decreases with increasing explored area. |
II. | The rectangular hyperbola represents the relation between species richness and area for angiosperm plants, birds, bats and freshwater fishes, for example. |
III. | Z represents the regression coefficient or the slope of the line. |
IV. | The value of Z lies in the range of 0.1 to 0.2 regardless of the taxonomic group or the region. |
V. | For frugivorous birds and mammals in the tropical forests of different continents, the slope is found to be 1.15. |
VI. | If the species area relationship is analysed for very large areas, the slope of the line is much steeper and Z value lies in the range of 0.6 to 1.2. |
1. | 3 | 2. | 4 |
3. | 5 | 4. | 6 |
All the following describe a stable biological community except:
1. | It should always show a significant increase in productivity from year to year |
2. | It must be either resilient or resistant to occasional natural disturbances |
3. | It must be either resilient or resistant to occasional man-made disturbances |
4. | It must be resistant to invasion by alien species |
I: | It is the Amazon rainforest area. |
II: | It is called as the ‘lung’ of planet Earth. |
III: | This area is very poor in biodiversity. |
1. | Only I and II | 2. | Only I and III |
3. | Only II and III | 4. | I, II and III |