Tropical Rainforest

By: Grant Harney

Tropical RainForest

There are tropical rain forests in South America, Asia, and Africa. It is a very unique biome because the conditions in which it's biotic factors are put in forces them to adapt in interesting ways in order to survive. For example, in the tropical rain forest, less than 2 percent of sunlight actually reaches the ground. Some other abiotic factors that affect the tropical rain forest are excessive rainfall and humid conditions.


The climate of the tropical rain forest is intense. The forest gets about 50 to 260 inches of rain each year, which is more than any other biome. Tropical rain forests are located around the equator, which means they get approximately 11 to 12 hours of sunlight a day. This also means that since this biome gets more direct sunlight than any other, the water on the ground is evaporated making it very humid, and also restarting the water cycle (explaining all the rain). The average temperature in the rain forest ranges from 68 degrees Celsius to 92 degrees Celsius.

Plant Life

There are over 170,000 of the world's 250,000 plant species that can be found in the rain forest biome. These plants grow year-round. These plants have a adapted in different ways to survive in the unique conditions of the rain forest. For example, some shorter trees have adapted to the lack of sunlight, which is caused by the taller trees, by growin bigger leaves. The more surface area, the more the plants can absorb. The trees that are taller is an adaptation as-well. This way the trees can compete for sunlight and water. Another great example of adaptation is found in the lianas plant. This plant looks like a vine, and roots itself into the ground and then climbs the trees so that it can attain sunlight. Drip tips is an adaptation in which the plants acquire a tapered point at the end of their leaves, so that water can quickly run off of them, preventing fungus and bacteria. In a drier forest, trees adapt to thick bark so that there is less evaporation, but in the rain forest, trees have smooth bark. This may also prevent other plants from growing on it's surface.


Animals in the tropical rain forest are very similar to the plants. They both adapt to their rainy, humid conditions. For example the jaguar, and other cats found in the jungle have adapted better climbing skills, so that they can pounce on their prey from trees above. As many of the nuts and berries in the rain forest have acquired hard shell-like exteriors to protect them from prey, birds such as toucans and parrots have adapted large beaks that can be used like nut-crackers. Another example is the spider monkey, which has adapted to the tall trees by growing a stronger tail and using it like a hand to glide from tree to tree. The parasol ant climbs up to 100 feet trees and collects special leaves, and then it takes them underground, and with a saliva that the ant produces, a fungus grows on the leaves.This fungus is the only food that the ants need to survive. Animals also interact with each other to survive. for example, the three-toed sloth is born with brown skin, but it is camouflaged by the algae that grows in its fur. This relationship is an example of mutualism, because the algae finds it's home in the sloth's fur, and the sloth finds camouflage from predators. There are plenty examples of competition in the tropical rain forest. Some are the plants fighting for sunlight, and the chimpanzees fighting for control over the trees with more fruit. An example of commensalism is the beetles and other insects that eat the algae that lives in the fur of the three-toed sloth. There are plenty examples of parasitism in the tropical rain forest. For example ticks will latch on to a leopard and suck it's blood for nutrients leaving the leopard at risk of lyme disease. Another example of mutualism in the forest is expressed in the relationship between the capuchin monkey, and the flowering trees. The monkey feeds off the nectar, and it then gets pollen on its face, and spreads it to other flowers.

Additional Information

The tropical rain forest has the most potential of any other biome for scientific discovery as far as new species go.

Tropical Threats

The largest threat to tropical rain forests is it's interaction with humans. More than half of the rain forests on the Earth have already been destroyed forever by man. The exponentially increasing population and need for resources and space has caused much of the tropical rain forest's to be cut or burned down. There are many endangered animals because of the destruction of their habitat. A couple examples are the golden lion tamarind monkey and the brown spider-monkey. This biome is extremely important to the existence of mankind, as it is essential in the conversion of carbon-dioxide into oxygen.