Why are tropical forests important to global biodiversity?

Tropical forests are vital to global biodiversity because they function as the world’s most significant reservoirs of biological variety, hosting the greatest concentrations of plant and animal species of any terrestrial ecosystem. Although they cover only about 2 percent of Earth’s surface, these forests are estimated to be home to perhaps two-thirds of all species on the planet.12

Their importance to biodiversity is rooted in several key factors:

• Unparalleled Species Richness: Tropical forests provide complex, dense habitats that support an incredible variety of ecological interactions and ancient evolutionary lineages. Many species are highly specialized, often restricted to specific forest types or regions, which contributes to high levels of endemism.23
• Biodiversity Hot Spots: Many moist tropical forests are classified as biodiversity hot spots—regions that host a significant number of endemic species but are also under severe threat from human activity.42
• Ecosystem Services: Beyond housing species, these forests provide critical services such as carbon sequestration, water cycle regulation, and soil stabilization, all of which maintain the environmental conditions necessary for life to thrive.12

Because so many species exist exclusively in these environments, the ongoing destruction of tropical forests poses a severe threat to global biological heritage, leading to the extinction of numerous species, many of which have yet to be scientifically described.12