Despite taking up 6% of the world’s surface, the rainforests, and especially tropical rainforests, are the biodiversity centres of our planet. Biologists state that more than half the Earth’s animals and plants exist here, and there are millions more to be discovered. To give testament to the biodiversity found in the tropics, Edward Wilson identified 43 species of ant on a single tree in the Peruvian Amazon, ants being the tropics most abundant insect. The amount on this one tree is roughly equal to the entire ant fauna of the British Isles. Rainforests hold many other biodiversity world records: scientists discovered 1, 500 species of beetle on a tree in Panama; in one hectare of Brazil’s tropical rainforest, researchers identified 425 different tree species; and in a section of Peru’s Manu National Park, 1,300 species of butterfly were discovered. Even in more temperate rainforests, such as those in New Zealand, the diversity is outstanding. For instance, 28 kinds of vine and herbaceous plant were found growing on one New Zealand yellowwood conifer. This set the word record for vascular epiphytes found on a single tree. The Earth’s tropical rainforests are extremely diverse, but are united by defining characteristics, such as climate, canopy structure, precipitation, and species diversity.

The remaining tropical wildernesses, those least disturbed by human hands, occur in New Guinea, Africa, and South America.