organisms (we must know that they exist before we can understand or use them) depend on the degree to which that task can be completed. Since all of human society depends directly or indirectly on our ability to manage plants, animals, and microorganisms effectively, the task is one of enormous importance.

In light of the rapid destruction of tropical forests, it is an especially urgent matter to catalog the organisms in those regions and to establish well-considered priorities for this undertaking. It is clear that most tropical forests will have been destroyed or severely damaged within the next 25 years, because of the size of the human population in the tropics and subtropics, already constituting a majority of the world’s people and growing explosively; the extensive poverty there, which afflicts well over a third of the people; and our collective ignorance of effective ways to manage tropical ecosystems so that they will be productive on a sustainable basis. By 2010, the only large blocks of undamaged forest remaining will be those in the western and northern Brazilian Amazon, the interior of the Guyanas, and the central Zaire (Congo) basin in Africa. All the forests in other parts of the tropics and subtropics (those in Mexico, Central America, the West Indies, Andean South America, the eastern and southern portions of the Amazon), all the forests of Africa outside the central Zaire basin, and all the forests of tropical and subtropical Asia will have been devastated by that time.

There will of course be exceptional preserved areas within these regions, their sizes depending on the effectiveness of local conservation programs and on the nature of the soils underlying particular pockets of vegetation. Some areas will simply be too steep to cultivate, others too rocky, and still others too wet. In these pockets of vegetation, populations of organisms will survive; however, they will be reduced to relatively few individuals in most cases, subjected to the effects of light and heat penetrating from the edges of the fragmented patches of forest in which they are surviving, and assaulted by human activities related to their greater accessibility. For example, the hunting of primates and other animals (discussed by Mittermeier in Chapter 16) is often greatly intensified when the surviving patches of vegetation are small. Because of the nature of small populations—they are unlikely to persist long owing to chance alone—and the increasing strains on these pockets of vegetation, many of the species that initially survive locally are likely to become extinct within a very few years.

The question arises as to whether large, important preserves such as Manu Park in Peru or the Tai Forest in the Ivory Coast can survive until the projected stabilization of the human population in the second half of the next century. As in other tropical and subtropical countries, human pressures in Peru and the Ivory Coast are incredible, and resources tend to be consumed in meeting the needs of rapidly growing populations with high proportions of poor, often malnourished people. Over the next few years, the confrontation between human needs and forest preservation, already evident in many areas, will become more acute. The protection of such major reserves is conceivable, however, if there is a genuine willingness to share resources on a global level—to provide major support from industrialized countries not merely for the protection of parks and reserves but for the creation of conditions in which all people can live with a measure of human



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