Student Introduction:

In a tropical ecosystem, there are many different life forms. The combination of weather and habitats allows many types of plants and animals to live there. In Costa Rica, there is an area of dry tropical forest in the Guanacaste Province which is not as well-known as the rainforest habitat. It has been reduced to only 10% of its original area. In this ecosystem live many kinds of birds, plants, insects, and other animals. Each one of them has a special job to do and role to fill. When even one type of plant or animal is removed from the system, things get out of balance. Maybe a beautiful bird is hunted for its feathers until there are no more of its kind, or another bird from some other ecosystem is brought into the area, and it manages to outproduce and outlive the native birds. Or many farms are made out of the wild lands, causing much wildlife to lose their homes and food and to die off. Land which was once wild forest has been cut down to plant crops or to build houses. All of these changes in turn produce other changes in the wildlife of an ecosystem. In Costa Rica, these changes are happening very fast.

Scientists are studying the wildlife in Costa Rica to learn more about it and learn ways to preserve the variety of life that exists there. They know that diversity of life, that is, many life forms, is a good thing and should be preserved. Many medicines have been discovered by studying tropical wildlife. And many more await discovery, if we can prevent the plants and animals there from being destroyed. Plants which we grow for food, such as corn, are stronger if we mix them with wild varieties. Entire ecosystems, such as wetlands, are necessary for cleaning water supplies, and being the incubators for fish and other wildlife.

But diversity doesn't exist only in the tropics. Even in your own backyard, many kinds of life forms can be found. However, areas where people have lived for many years have been changed greatly from their natural state. Now, when we look at the plants or animals in a city ecosystem, many of them which were there in years past are missing. And some kinds of plants and animals which weren't there before are now taking over from the native species. These changes are causing lasting changes in our lives as well as the quality of life on our whole earth. We need to learn how to slow down these changes, and turn some of them around, to insure the continuation of life on earth as we know it.