Chapter 02 · Nature, land & waterBiodiversity & Nature
Biodiversity hotspot
Definition
A biogeographic region meeting two strict criteria set by Conservation International: at least 1,500 endemic vascular plant species (plants found nowhere else), and 30% or less of its original natural vegetation remaining. Thirty-six regions qualify, from Madagascar to the Tropical Andes; the concept originates with ecologist Norman Myers (1988), formalised in a 2000 Nature paper.
References
Two criteria (≥1,500 endemic plants; ≤30% original vegetation); 36 hotspots; 2.5% of land surface; endemic-species shares.
Overview
What it means
The criteria encode a dual logic — irreplaceability and vulnerability. The 36 hotspots cover only about 2. 5% of Earth's land surface but hold more than half of the world's endemic plant species and nearly 43% of endemic bird, mammal, reptile and amphibian species. Conservation in these areas yields outsized returns per dollar — the framework's explicit purpose is prioritisation under scarcity.
How it is used
Hotspots channel funding from Conservation International's Critical Ecosystem Partnership Fund, GEF programmes and national protected-area planning. The concept complements finer-scale designations such as Key Biodiversity Areas, many of which sit within hotspots.
Why it matters
The hotspot concept proved that conservation triage works: it shaped two decades of conservation geography and remains the most influential prioritisation framework — though critics note it under-weights wilderness areas with low endemism and ecosystem services elsewhere.