Facts about Tropical Rainforests
- Scientists consider a tropical forest a rainforest if it rains over 100 inches (254 centimeters) each year.
- Scientists consider a rainforest tropical if the temperature is above 70° Fahrenheit (21° Celsius) year-round.
- Tropical rain forests are found near the earth's equator between the latitude of 22.5 degrees north and south of the equator. This range is just south of the Tropic of Cancer and north of the Tropic of Capricorn, which correlates to the range over the Earth where the sun is located directly above this latitude of the Earth during some portion of the year.
- Tropical rain forests are found in Central America, South America, Africa, southern Asia and Australia.
- Scientists estimate that tropical rainforests cover about 6 percent of the Earth's land surface, but this number is decreasing each year.
- The Amazon River basin is the location of half of the Earth's remaining tropical rainforests. This 1.4 billion acre area is located in the countries of Brazil, Peru, Columbia, Ecuador, Guyana, Venezuela, French Guiana and Surinam.
- Scientists are finding that plants from rainforests can help heal cancer and other dangerous diseases. Currently, over 35 percent of all prescription medications contain ingredients from rainforests. Many of the rainforest plants used for medicines are only found in specific rainforests. The chemicals from the rosy periwinkle plant, found only in the rainforests of Madagascar, are used by scientists to make medicine to treat leukemia and other cancers.
- Cacao plants are found in tropical rainforests in Central and South America. Cacao beans from these plants are used to make chocolate. Other rainforest plants like cinnamon spice or the vanilla orchid are used to make flavors that are used to make popular sweet foods.
The Madagascar rosy periwinkle is used to treat leukemia and other cancers.
Cacao beans on a cacao plant in South America
Tropic Rainforest Layers
- Plant and animal life grows in 4 distinct layers in a tropical rainforest including the emergent layer, upper canopy, lower canopy and understory.
- The understory is the ground layer of a tropical rainforest. Very little sunlight with a small amount of rainwater reaches this layer. Insects, amphibians and reptiles populate the understory, including some of the most poisonous reptiles on Earth. Plants that need a lot of light struggle to survive in the understory.
- The lower canopy has much less sunlight than the upper canopy. Less rainfall also reaches this layer with much of the water evaporating or collecting on leaves in the upper canopy and emergent layer
- The upper canopy is the layer under the emergent layer. This layer receives partial sunlight, with shade from the emergent layer. A majority of animal life thrives in the upper canopy where there is plenty of nuts, fruit and leaves to eat and rainwater, which collects on leaves, to drink.
- The emergent layer is the top layer of the rainforest. This layer receives direct sunlight and direct exposure to wind and rain.
The Emergent layer of the rainforest recieves the most sunlight and rain.