Q.56 Given below are two statements:
Statement-I: Hot spots of biodiversity must contain at least 0.5% or 1500 of
world’s 3,00,000 plant species as endemic.
Statement-II: Hot spots of biodiversity must have at least 70% or more of its
primary vegetation.
In the light of the above statements, choose the correct answer
from the options given below:
(A) Both Statement-I and Statement-II are true
(B) Both Statement-I and Statement-II are false
(C) Statement-I is true but Statement-II are false
(D) Statement-I is false but Statement-II are true
Both Statement-I and Statement-II are true, so the correct answer is (A).
Criteria Analysis
Biodiversity hotspots are defined by two key criteria from Conservation International: a region must contain at least 0.5% (or 1,500) of the world’s total vascular plant species as endemics, and it must have lost at least 70% of its primary (original natural) vegetation. Statement-I matches this exactly, referring to 0.5% or 1,500 endemic plant species out of approximately 300,000 total. Statement-II also aligns precisely, specifying at least 70% loss of primary vegetation (often worded as “at least 70% or more” to emphasize severe habitat destruction).
Option Breakdown
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(A) Both true: Correct, as both statements directly reflect the standard hotspot criteria established by Norman Myers and refined by Conservation International.
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(B) Both false: Incorrect; these are the globally accepted definitions used to identify 36 hotspots covering just 2.4% of Earth’s land but holding over 50% of endemic plants.
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(C) I true, II false: Incorrect; Statement-II is not false—70% vegetation loss is a core requirement to prioritize threatened areas.
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(D) I false, II true: Incorrect; Statement-I is accurate, with the 0.5%/1,500 endemic threshold unchanged since 2000.
Introduction to Biodiversity Hotspots Criteria
Biodiversity hotspots criteria identify Earth’s most critical conservation areas, focusing on regions with exceptional endemism and severe habitat loss. These hotspots, numbering 36 worldwide, harbor over 60% of terrestrial species despite covering only 2.4% of land. Understanding the precise thresholds—like 0.5% or 1500 endemic plant species and 70% primary vegetation loss—is essential for exams like NEET and environmental science.
Core Biodiversity Hotspots Criteria
Two strict criteria qualify a region as a biodiversity hotspot, per Conservation International:
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Endemism Threshold: Must contain ≥0.5% (1,500 species) of global vascular plants (~300,000 total) found nowhere else. This ensures irreplaceable biodiversity.
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Habitat Loss Threshold: Must have lost ≥70% of original primary vegetation, highlighting urgent threats from deforestation and human activity.
These were formalized by Norman Myers in 1988 and updated in 2000.
MCQ Solution: Statement-I and Statement-II
Question: Statement-I: Hot spots must contain ≥0.5% or 1500 of world’s 300,000 plant species as endemic. Statement-II: Hot spots must have ≥70% of primary vegetation lost.
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Both statements match the exact criteria verbatim.
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Answer: (A) Both true.
| Option | Why Incorrect/Correct |
|---|---|
| (A) Both true | Matches endemism (0.5%/1500) and vegetation loss (≥70%) criteria precisely |
| (B) Both false | Falsely denies established definitions used globally |
| (C) I true, II false | Ignores proven 70% habitat loss rule |
| (D) I false, II true | Misstates endemic threshold, which is fixed at 0.5%/1500 |
Examples of Biodiversity Hotspots
India hosts four: Himalayas, Indo-Burma, Sundalands, Western Ghats/Sri Lanka. The Western Ghats, for instance, have >4,000 endemic plants (>1% globally) and >70% forest loss in parts. These areas drive conservation priorities.
Why These Criteria Matter
The biodiversity hotspots criteria prioritize action: high endemism means unique species at risk, while 70% vegetation loss signals crisis. They guide funding for 1.2 million km² of protected areas. For students, mastering this aids exam success in ecology topics.
