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Perceptions of the need for environmental conservation in Africa held by those outside the continent are sometimes expressed in terms that seem opposed to the legitimate priorities and aspirations of African peoples (in meeting which agriculture and livestock management must remain crucial). It is not surprising that projections based upon the assumptions from these external sources frequently end in pessimism. A more constructive approach is to identify ways in which to more fully integrate wild plant life, crops, and animals, which can be expressed in the concept of productive countryside. The capacity and precision of resource surveys have been greatly enhanced by remote sensing, and this has been coupled with the worldwide transmissibility of information. Research and interest in agroforestry have expanded and become institutionalized. Above all, however, confidence must be put in the capacities of many millions of African farmers to expand agriculture while working toward reintegration with wild plant life. Animal life

Africa includes two regions of the zoographic area known as the Paleotropical realm: the Afrotropical region, which comprises the continent south of the Sahara and the southwestern part of Arabia, and the Madagascan region. The continent also includes a southern part of the Palaearctic (Old World) region of the Holarctic realm (i.e., the lands of the Northern Hemisphere), consisting of northwestern and North Africa south to roughly the Tropic of Cancer.

Genera and distribution

Africa is best known for the enormous diversity and richness of its wildlife. It has a greater variety of large ungulates, or hoofed mammals (some 90 species), and freshwater fish (2,000 species) than any other continent. Mammals

The main group of herbivores are the African antelope, which belong to four subfamilies of the ox family (Bovidae). The first subfamily is the oxlike Bovinae, which is further subdivided into the African buffalo and the twist-horned antelope, including the eland (the largest of all antelope), kudu, nyala, and bushbuck. The second subfamily is the duiker, a small primitive bovid that lives in the thickets, bush, and forests. Third is the “horse antelope,” further divided into sabre-horned sable, roan, and oryx antelope; the “deer antelope,” kongonis, hartebeest, topi, gnu (wildebeest), and blesbok, all mostly inhabitants of the open plains; and the “marsh antelope,” waterbuck, lechwe, kob, puku, and reedbuck. The fourth subfamily is the antelope proper, divided into two distinct tribes, the first of which includes royal, dik-dik, klipspringer, oribi, steenbok, and grysbok and the second of which includes gazelle, impala, springbok, and gerenuk. Other well-known large African herbivores include the zebra, giraffe, hippopotamus, rhinoceros, and African elephant.

Cape, or African, buffalo (Syncerus caffer).Mark Boulton—The National Audubon Society Collection/Photo Researchers

Probably no group of animals is more identified with Africa than its Carnivora (the order of flesh-eating mammals), of which there are more than 60 species. In addition to the better-known big (or roaring) cats—the lion, leopard, and cheetah—are the wild dog, hyena, serval (a long-limbed cat), wildcat, jackal, fox, weasel, civet, and mongoose. These predators and scavengers are vital in maintaining the ecological equilibrium of the areas that they inhabit.

West African, or masked, chimpanzee (Pan troglodytes verus).Helmut Albrecht/Bruce Coleman Ltd.

Red-bellied lemur (Eulemur rubriventer) in the eastern Madagascar rainforest near Ranomafana. © David Curl/Oxford Scientific Films Ltd.The primates include some 45 species of Old World monkeys, as well as two of the world’s great apes—the chimpanzee and the world’s largest ape, the gorilla. Presimian primates—such as pottos (African lemurs) and galagos (bush babies, or small arboreal lemurs), as well as Lorisidae (a family of arboreal lemurs, moving with a slow, delicate crawl)—are mainly small and nocturnal, but in Madagascar, where there are no true monkeys, the world’s most diverse assemblage of large and small diurnal and nocturnal presimian lemurs survives.

Marine mammals include one Mediterranean and one South African seal (the Cape fur seal) and two Sirenia (an order of aquatic herbivores)—the dugong and the manatee. In addition, whales, porpoises, and dolphins frequent Africa’s coastal waters.

Africa’s large number of endemic mammal species is second only to that of South America. They include several families of the ungulate order Artiodactyla (composed of mammals with an even number of toes), such as giraffes and hippopotamuses. Some families of Carnivora—such as civets (of the Viverridae family), their smaller relations the genets, and hyenas—are chiefly African. The rodent family of jumping hares (Pedetidae) is endemic, and one order, the aardvark (Tubulidentata)—a large nocturnal burrowing mammal, with one species—is exclusively African. Madagascar also has a remarkable insect-eating family, the tenrecs (animals with long pointed snouts, some of which are spiny and tailless).

Streaked tenrec (Hemicentetes semispinosus).H. Uible/Photo Researchers Birds

South of the Sahara the birdlife includes nearly 1,500 resident species, to which must be added another 275 species that are either resident in northwestern Africa or else are Palaearctic winter migrants; the migrants once totaled perhaps two billion individuals, but their numbers have been reduced considerably by severe droughts and by human land use and predation. Birds are mainly of Old World families, but of those that are endemic the most noteworthy are perhaps the ostrich, shoebill, hammerkop (a brown heronlike bird), and secretary bird (a large long-legged predatory bird) and the touracos (brightly coloured birds, some with helmetlike crests). Other families, such as bustards, sand grouse, honey guides (small dull-coloured birds, several species of which are noted for leading people to the nests of honeybees, in order to feed on them after the nests have been broken), and larks, are predominantly African. There are many avian predators of land mammals, including eagles, hawks, and owls; more of fish, such as storks, waders, and a few species of kingfishers; and even more of insects, this latter group usually being of benefit to humans. Scavengers include vultures and the large marabou stork.

Ostriches (Struthio camelus); at left is the male.David C. Houston—Bruce Coleman Ltd. Reptiles and amphibians

Reptiles, of which there are few endemic families, have mainly Old World affinities. Those most likely to be seen include lizards of the agamid family, skinks (a family of lizards characterized by smooth overlapping scales), crocodiles, and tortoises. Endemic reptiles include girdle-tailed and plated lizards. Within the African realm, lizards of the iguana family and boa constrictors occur only in Madagascar. Large vipers are abundant and varied; certain species have extremely toxic venom, but they are seldom encountered. A wealth of both colubrine snakes (with fangs at the posterior end of the upper jaw) and elapine snakes (with fixed poison fangs at the front of the upper jaw) include such highly venomous elapine species as mambas.

Amphibians also belong mainly to Old World groups. Salamanders and hylid tree frogs (having teeth in the upper jaw) are confined to the Palaearctic northwest. Abundant commoner frogs and toads include such oddities as the so-called hairy frog of Cameroon, whose hairs are auxiliary respiratory organs. The frog subfamily Phrynomerinae is exclusively African. Arthropods