Key differences, features, and comparative analysis of Category and Numbers.
| Category | Numbers |
|---|---|
| Global species | Described (IUCN 2004): >1.5 million · Robert May's estimate: 7 million · Extreme estimates: 20–50 million |
| Composition | Animals >70% · Plants ≤22% · Insects = 70% of animals (7 of every 10 animals) · Fungi > fishes + amphibians + reptiles + mammals combined |
| India | Land area 2.4% · Species share 8.1% · One of 12 mega-diversity countries · 45,000 plants · 90,000 animals · yet to find: >1,00,000 plants, >3,00,000 animals |
| Latitude | Tropics = 23.5° N to 23.5° S · Colombia 1,400 birds · India >1,200 · New York (41° N) 105 · Greenland (71° N) 56 · Ecuador forest = 10× the vascular plants of a Midwest-USA forest |
| Amazon | Plants >40,000 · Fishes 3,000 · Birds 1,300 · Mammals 427 · Amphibians 427 · Reptiles 378 · Invertebrates >1,25,000 · Undiscovered insects ≥2 million · Produces 20% of atmospheric oxygen · Called the 'lungs of the planet' |
| Extinction | Pacific Island birds lost: >2,000 · IUCN 2004: 784 = 338 vertebrates + 359 invertebrates + 87 plants (in 500 years) · Last 20 years: 27 species · Currently threatened: 15,500 · Rate: 100–1,000× faster than pre-human · Half of all species could go in 100 years |
| % facing extinction | Amphibians 32% > Gymnosperms 31% > Mammals 23% > Birds 12% |
| Habitat loss | Tropical rain forests: once >14% of land surface → now ≤6% |
| Alien invasion | Nile perch in Lake Victoria wiped out >200 species of cichlid fish |
| Medicine | >25% of drugs sold worldwide come from plants · 25,000 plant species used in traditional medicine |
| Hotspots | 25 + 9 = 34 · cover <2% of land · strict protection could cut mass extinctions by ~30% · 3 in India |
| India's protected areas | 14 biosphere reserves · 90 national parks · 448 wildlife sanctuaries |
| Summits | Rio de Janeiro 1992 (Earth Summit) · Johannesburg 2002 (World Summit on Sustainable Development, 190 countries, 2010 target) |
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