
This makes it easy to walk through undisturbed, mature rainforest. The undergrowth in a rainforest is restricted in many areas by the poor penetration of sunlight to ground level. Rainforests are also responsible for 28% of the world's oxygen turnover, sometimes misnamed oxygen production, processing it through photosynthesis from carbon dioxide and consuming it through respiration.

Tropical rainforests have been called the "jewels of the Earth" and the "world's largest pharmacy" because over one-quarter of natural medicines have been discovered there. It has been estimated that there may be many millions of species of plants, insects and microorganisms still undiscovered in tropical rainforests. Around 40% to 75% of all biotic species are indigenous to the rainforests.

The monsoon trough, alternatively known as the intertropical convergence zone, plays a significant role in creating the climatic conditions necessary for the Earth's tropical rainforests. Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm (68-78 inches). This is a big problem with extinction to animals and is one of the biggest threats to the rare Spix's Macaw, and other birds. Despite its beauty, many animals such as birds, rainforest tigers and also insects die from plant poisoning and low habitat environmental safety. The Rainforest is filled with amazing creatures and plants. In Rio 2, Blu and his family head into the Amazon Rainforest to search for more of their kind. At the end of Rio, Blu and Jewel fly through the rainforest with their three chicks, Bia, Carla, and Tiago, and sing with their friends. In Rio, Blu and Jewel walk through the Tijuca Forest, just outside Rio de Janeiro's Favela Rocinha at night to go to sleep, and meet Rafael the next morning, who helps them in their quest to remove the chain on their legs. The Rainforest is a greenish area rich in biodiversity. Tropical forests in the world, dark green the tropical wet monsoon forest, light green the tropical rainforest. The rainforest in the Atlantic Rainforest, Brazil
