The tropical rainforests of the world exist around the equator. These forests have an average temperature of 80 degrees F and an average rainfall of 160 to 400 inches of rain per year. A combination of the high heat and heavy rainfall makes these humid jungles some of the most diverse areas on earth.
Strangler fig trees grow from a fig seed left in the canopy of a host tree by a passing bird or climbing animal. The seed germinates and sends roots down to the forest floor; it then begins to grow around the host tree, eventually strangling it to death. Once the host tree has died and rotted away, a massive fig tree with a hollow trunk remains. The benefit of this aggressive growing tactic is the lack of competition for light at the upper reaches of the forest canopy.
Like the strangler fig, many species of orchid attach their roots to the upper branches of a host tree in order to escape the fierce competition for light at the forest floor. Unlike the strangler fig, the orchid does not damage or kill its host; instead it simply exists attached to the upper branches, absorbing moisture and nutrients from the air through its exposed root system. Some orchids do grow on the forest floor and still others attach themselves to rocks and other inhospitable terrain. With 20,000 known species, the orchid family is a diverse group of flowering plants.
Lianas are a large family of climbing vines that germinate from seeds scattered on the forest floor and send out tendrils that wind around trees and saplings. Eventually these vines reach the top of the forest canopy and hang down over the tops of the trees. This vast network of vines makes a connecting system for animals and insects of the forest. Some members of the liana vine family reach lengths of 3,000 feet.
The bromeliad family includes the well-known pineapple fruit, but the species is far more diverse then this one popular fruit. A characteristic trait of this family is a series of long, waxy leaves that spiral outward, forming a cup-shaped vessel in the center. Inside, water collects and attracts insects and critters that live in and among the leaves. Some bromeliads grow on forest floors, while others attach to the trunks of trees for more competitive access to light.
Bougainvillea is a familiar flowering vine for any gardener who has lived in, or visited, a warm-climate garden. Like the bromeliad, the bougainvillea creates a unique ecosystem within its self. A mass of tangled and knotted thorny branches creates an ideal habitat for insects, reptiles and small mammals. Bougainvillea grow wild in the rainforest and spread quickly, reaching heights of 40 feet or higher. In the dryer seasons this plant produces a profusion of brightly colored flowers at the end of its long, thorny branches.