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Question
Give three hypotheses for explaining why tropics show greatest levels of species richness.
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Solution
- Speciation is generally a function of time. Temperate regions have been repeatedly glaciated since ancient times, while tropical latitudes have remained undisturbed for millions of years. Hence, there has been more time for species to evolve and diversify.
- The tropical environment is different from the temperate environment and shows fewer seasonal changes. This stable environment has encouraged niche specialisation, leading to greater species diversity.
- More solar energy is available in tropical regions, which leads to greater productivity and, indirectly, to more extraordinary biodiversity.
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RELATED QUESTIONS
The following graph shows the species-area relationship. Answer the following questions as directed.
(a) Name the naturalist who studied the kind of relationship shown in the graph. Write the observations made by him.
(b) Write the situations as discovered by the ecologists when the value of ‘Z’
(Slope of the line) lies between:
- 0.1 and 0.2
- 0.6 and 1.2
What does ‘Z’ stand for?
(c) When would the slope of the line ‘b’ become steeper?
Short answer type question
Tropical regions exhibit species richness as compared to polar regions. Justify.
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All are true regarding graph showing species richness - area relationship, EXCEPT ______.
Which of the following is an observation of Alexander von Humboldt's documented pattern in ecology?
Species richness - area relationship is given by ______.
Which of these is true about tropical environments?
Which of these is true about tropical environments?
"Species richness increased with increased explored area but only a limit". This statement was given by.
Which one of the following is not a major characteristic feature of biodiversity hot spots?
A species-area curve is drawn by plotting the number of species against the area. How is it that when a very large area is considered the slope is steeper than that for smaller areas?
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The relation between species richness and area for a wide variety of taxa turns out to be a rectangular hyperbola. Give a brief explanation.
Write the inference drawn by Alexander von Humboldt after his extensive explorations of South American jungle.
Study the graph given below:
As per Alexander von Humboldt, what do the symbols S, A, Z and C in the graph stand for, in respect of a species and area relationship?
Distribution of diversity on earth shows that biodiversity from higher latitudes to lower latitudes ______.
The relation between species richness and area for a wide variety of taxa appears as ______.
Alexander von Humboldt observed that, within a region species richness ______ with increasing explored area.
Rivet Popper Hypothesis is an analogy to explain the significance of ______.
Who observed that within a region, species richness increased with increasing explored area, to a certain limit?
Match the scientist in column I with their contribution in column II and choose the correct option.
| Column I | Column II | ||
| i. | Alexander Van Humboldt | a. | Estimated 7 million species round the globe |
| ii. | Robert May | b. | Rivet popper hypothesis |
| iii. | David Tillman | c. | Species Area Relationship |
| iv. | Paul Ehrlich | d. | Productivity stability hypothesis |
