Tropical rainforests are located around the equator, in the area between the Tropic of Cancer (23.5 degree N latitude) and the Tropic of Capricorn (23.5 degree S latitude).
The forests lying within this band are referred to as the rainforests. They occur in South and Central America, Africa, Oceania (the islands around Australia) and Asia. Tropical rainforests cover only about 7% of the Earth's surface and the largest of these lie in the Amazon River Basin (South America), the Congo River Basin (western Africa) and throughout much of southeast Asia. Smaller rainforests are located in Central America, Madagascar, Australia and nearby islands, India and other locations in the tropics.
Rainforests are important because:
- The rainforests recycle and clean water. Tropical rainforest trees and plants remove carbon dioxide from the atmosphere and store it in their roots, stems, leaves and branches thus decreasing the greenhouse effect.
- A lot of food products were originally found only in the rainforests. These include rice, coffee, tea, cashew nuts, bananas, pineapple, cucumber, cocoa (chocolate), avocados, papaya, guava, mango, tapioca, yams, sweet potato, okra, cinnamon, vanilla, nutmeg, mace, ginger, cayenne pepper, cloves, oranges, grapefruit, lemons, limes, passion fruit, peanuts, sugar cane and coconuts.
- A lot of medical research is being done around plants in rainforests to create medicines that fight disease and illness.
Parts of a Rainforest
Different animals and plants live in different parts of rainforests. A rainforest can be divided into the following parts:
- Emergents: Giant trees that are much higher than the average canopy height. They house many birds and insects.
- Canopy: The upper part of the tree. Insects, birds, reptiles and mammals live here.
- Understory: The dark environment under the leaves but over the ground.
- Forest Floor: Animals lurk on this floor where the soil is only about 3 to 4 inches thick and is ancient. Thick clay lies underneath the soil. Once damaged, the soil of a tropical rainforest takes many years to recover.
Animals from the Rainforests
Anaconda: The anaconda is the biggest snake in the world. Also known as the water boa, this giant meat-eater lives in swampy areas of tropical South America.
Assassin Bugs: Assassin bugs are killer insects that eat other bugs. They lie in wait for insects and then inject a toxin into their prey.
Binturong: The binturong (Arctictis binturong) is a large, rare mammal that lives in trees in the dense forests of Southeast Asia. It has thick, black fur and a long, muscular tail that is used as another hand. Binturongs grow to be up to about 5 feet. Like other civets, these nocturnal animals use scent marks to communicate with other binturongs.
Caped Lizard: Chlamydosaurus (meaning "caped lizard") is a rare find and is native to New Guinea and North Australia. Its frill is a 7 to 14 inch flap of skin that completely encircles its head. It opens this brightlycoloured frill to frighten enemies. It can run on all four legs or with the front legs off the ground.
Queen Alexandra's Birdwing: This is the largest butterfly in the world, with a wingspan up to 1 foot (30 cm). This rare butterfly is found in the lowland forests of northern Papua New Guinea.
Quetzals: These are the most colourful birds of the Amazon rainforests. They are solitary birds and poor flyers. They are quite close to becoming extinct.
Did You Know?
The tropical rainforest has just two seasons-the wet season and the dry season-and it rains through the year. Rainforests get over 80 inches (2 m) of rain each year. This is about 1.5 inches (3.8 cm) of rain each week!