The island of Madagascar has been described as an "alternate world" or a "world apart" because of the uniqueness and rarity of many of its plant and animal species. Their characteristics are believed to reflect the island's origins as a part of Gondwanaland and its many millions of years of virtually total isolation following the breakup of the landmass. Thus, certain plants, including the "traveler's" tree (so called because its trunk holds potable water), are found both in Madagascar and on the South American continent, but not in Africa. Many of the most characteristic African species, particularly such large mammals as the elephant, rhinoceros, giraffe, zebra, and antelope and such beasts of prey as the lion and leopard, do not exist in Madagascar. In addition, the island has been spared the great variety of venomous snakes indigenous to the African continent. Although it is assumed that most life forms on the island had an African (or South American) origin, many millions of years of near-complete isolation have allowed old species--elsewhere extinct--to survive and new species unique to the island to evolve. Thus, a great number of plant, insect, reptile, and fish species are found only in Madagascar, and all indigenous land mammal species--sixty-six in all--are unique to the island. Madagascar was once covered almost completely by forests, but the practice of burning the woods to clear the land for dry rice cultivation has denuded most of the landscape, especially in the central highlands. Rain forests are concentrated on the steep hillsides along a slender north-south axis bordering the east coast, from the Tsaratamana Massif in the north to Tolagnaro in the south. Secondary growth, which has replaced the original forest and consists to a large extent of traveler's trees, raffia, and baobabs, is found in many places along the east coast and in the north. The vegetation of the central highlands and the west coast is for the most part savanna or steppe, and coarse prairie grass predominates where erosion has not exposed the orange-red lateritic soil. In the southwest, the vegetation is adapted to desert conditions. The remaining rain forest contains a great number of unique plant species. The country has some 900 species of orchids. Bananas, mangoes, coconut, vanilla, and other tropical plants grow on the coasts, and the eucalyptus tree, brought from Australia, is widespread. Wood and charcoal from the forests are used to meet 80 percent of domestic fuel needs. As a result, fuelwood has become scarce. The World Bank in 1990 launched an environmental program that has increased the planting of pine and eucalyptus to satisfy fuel needs. Data as of August 1994
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