State of the Rainforest 2014

huge variety of plants and animals. The many theories are not mutually exclusive. 19 Probably, all these factors have been involved in shaping the rich diversity of the world’s rainforests as we know them today. Human beings have also played a part in the interaction. In the Amazon there are traces of hunter-gatherer societies dating some 9000 years back, and of agricultural societies existing 4500 years ago. Human life has also been documented in the rainforests of Africa and Asia 20 dating several thousand years back in time. While species extinction thousands of years ago has been linked to human activity in some places, human activity is not necessarily synonymous with destruction. There are also signs that people, in the interaction with their environment, have actually strengthened species diversity. Wemay need to re-adjust our notions of rainforests as primeval, virgin tracts untouched by humans. Disappearing diversity The last time the golden toad ( Incilius periglenes ) was seen, was in a nature reserve in Costa Rica in 1989. The species of our planet

The two countries with the greatest diversity of mammals are among the world’s largest rainforest countries, Indonesia (670 species) and Brazil (648 species). According to an analysis by the IUCN Red List, 18 Indonesia is also the country with the highest number of threatened mammals in the world. The fact that new species are still being discovered is a clear indication of the vast and unmapped biodiversity in the world’s rainforests. Why are there so many species? In general, the diversity of plants and animals increases dramatically from the polar regions to the tropics. But we do not yet know why rainforests are so exceptionally rich in biodiversity. Is it due to inter- species struggle for specialization? Or is it a matter of the gradual accumulation of species under relatively stable tropical forest conditions over millions of years? Other theories hold that species evolve more rapidly in warm climates; that variations in micro-climate and periods where pockets of rainforest have been isolated in a drier or colder climate have fostered diversity; or that the geological changes that elevated lowlands to mountains (like the Andes) have stimulated the

Biodiversity is concentrated in the rainforest

Russian Federation

United States

China

Mexico

Philippines

Vietnam

India

Venezuela

Costa Rica

Thailand

Malaysia

Colombia

Papua New Guinea

Democratic Republic of the Congo

Ecuador

Indonesia

Brazil

Tanzania

Peru

Bolivia

Madagascar

Australia

Total number of amphibian, bird, mammal, reptile, and vascular plant species

South Africa

Argentina

60 000 25 000 10 000

NB: Only values above 10 000 are shown

Rainforest country

Source: Mongabay.com

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STATE OF THE RAINFOREST 2014