The ecological balance refers to diverse forms and ecosystems that are interconnected and interdependent. The more diverse, the more resilient an ecosystem will be. The ecological balance is of crucial importance, but also quite sensitive to disturbance. With one life form depending on another, and a third depending on a fourth, the disappearance of one will always affect the other. The destruction of the rainforest is a major threat to the delicate balance.
5 to 80 million species of plants and animals comprise the "biodiversity" of planet Earth. Tropical rain forests-covering only 7% of the total dry surface of the Earth-hold over half of all these species. Of the tens of millions of species believed to be on Earth, scientists have only given names to about 1.5 million of them, and even fewer of the species have been studied in depth. Many of the rain forest plants and animals can only be found in small areas, because they require a special habitat in which to live. This makes them very vulnerable to deforestation. If their habitat is destroyed, they may become extinct. Every day, species are disappearing from the tropical rain forests as they are cleared. We do not know the exact rate of extinction, but estimates indicate that up to 137 species disappear worldwide each day. The loss of species will have a great impact on the planet. We are losing species that might show us how to prevent cancer or help us find a cure for AIDS. Other organisms are losing species they depend upon, and thus face extinction themselves.