TSMF is generally found in large, discontinuous patches centered on the equatorial belt and between the Tropics of Cancer and Capricorn, TSMF are characterized by low variability in annual temperature and high levels of rainfall. Forest composition is dominated by evergreen and semi-evergreen deciduous treespecies. These trees number in the thousands and contribute to the highest levels of species diversity in any terrestrial major habitat type. In general, biodiversity is highest in the forest canopy. The canopy can be divided into five layers: overstory canopy with emergent crowns, a medium layer of canopy, lower canopy, shrub level, and finally understory. These forests are home to more species than any other terrestrial ecosystem: Half of the world's species may live in these forests, where a square kilometer may be home to more than 1,000 tree species. These forests are found around the world, particularly in the Indo-Malayan Archipelago, the Amazon Basin, and the African Congo Basin. A perpetually warm, wet climate makes these environments more productive than any other terrestrial environment on Earth and promotes explosive plant growth. A tree here may grow over in height in just 5 years. From above, the forest appears as an unending sea of green, broken only by occasional, taller "emergent" trees. These towering emergents are the realm of hornbills, toucans, and the harpy eagle. The canopy is home to many of the forest's animals, including apes and monkeys. Below the canopy, a lower understory hosts to snakes and big cats. The forest floor, relatively clear of undergrowth due to the thick canopy above, is prowled by other animals such as gorillas and deer. All levels of these forests contain an unparalleled diversity of invertebrate species, including New Guinea’s stick insects and butterflies that can grow over in length. Many forests are being cleared for farmland, while others are subject to large-scale commercial logging. An area the size of Ireland is destroyed every few years.
Types
The biome includes several types of forests:
Lowland equatorial evergreen rain forests, commonly known as tropical rainforests, are forests which receive high rainfall throughout the year. These forests occur in a belt around the equator, with the largest areas in the Amazon basin of South America, the Congo basin of central Africa, and parts of the Malay Archipelago. About half of the world's tropical rainforests are in the South American countries of Brazil and Peru. Rainforests now cover less than 6% of Earth's land surface. Scientists estimate that more than half of all the world's plant and animal species live in tropical rainforests.
Tropical seasonal forests, also known as moist deciduous, monsoon or semi-evergreen seasonal forests, have a monsoon or wet savannah climates : receiving high overall rainfall with a warm summer wet season and a cooler winter dry season. Some trees in these forests drop some or all of their leaves during the winter dry season. These forests are found in South Florida, parts of South America, in Central America and around the Caribbean, in coastal West Africa, parts of the Indian subcontinent, and across much of Indochina.
Montane rain forests are found in cooler-climate mountainous areas. Those with elevations high enough to regularly encounter low-level cloud cover are known as cloud forests.
