Fauna of Africa

The fauna of Africa are all the animals living in Africa and its surrounding seas and islands. The more characteristic African fauna are found in the Afro-tropical realm. Lying almost entirely within the tropics, and stretching equally north and south of the equator creates favorable conditions for variety and abundance of wildlife. Africa is home to many of the world's most recognizable fauna such as lions‚ rhinoceroses‚ cheetahs‚ giraffes‚ antelope, hippopotamuses, leopards, zebras‚ and elephants, among many others.

Whereas the earliest traces of life in fossil record of Africa date back to the earliest times, the formation of African fauna as we know it today, began with the splitting up of the Gondwana supercontinent in the mid-Mesozoic era.

After that, four to six faunal assemblages, the so-called African Faunal Strata (AFSs) can be distinguished. The isolation of Africa was broken intermittently by discontinuous "filter routes" that linked it to some other Gondwanan continents (Madagascar, South America, and perhaps India), but mainly to Laurasia. Interchanges with Gondwana were rare and mainly "out-of-Africa" dispersals, whereas interchanges with Laurasia were numerous and bidirectional, although mainly from Laurasia to Africa. Despite these connections, isolation resulted in remarkable absences, poor diversity, and emergence of endemic taxa in Africa. Madagascar separated from continental Africa during the break-up of Gondwanaland early in the Cretaceous, but was probably connected to the mainland again in the Eocene.

The first Neogene faunal interchange took place in the Middle Miocene (the introduction of Myocricetodontinae, Democricetodontinae, and Dendromurinae). A major terrestrial faunal exchange between North Africa and Europe began at about 6.1 Ma, some 0.4 Myr before the beginning of the Messinian salinity crisis(for example introduction of Murinae, immigrants from southern Asia).

During the early Tertiary, Africa was covered by a vast evergreen forest inhabited by an endemic forest fauna with many types common to southern Asia. In the Pliocene the climate became dry and most of the forest was destroyed, the forest animals taking refuge in the remaining forest islands. At the same time a broad land-bridge connected Africa with Asia and there was a great invasion of animals of the steppe fauna into Africa. At the beginning of the Pleistocene a moist period set in and much of the forest was renewed while the grassland fauna was divided and isolated, as the forest fauna had previously been. The present forest fauna is therefore of double origin, partly descended of the endemic fauna and partly from steppe forms that adapted themselves to forest life, while the present savanna fauna is similarly explained. The isolation in past times has resulted in the presence of closely related subspecies in widely separated regions Africa, where humans originated, shows much less evidence of loss in the Pleistocene megafaunal extinction, perhaps because co-evolution of large animals alongside early humans provided enough time for them to develop effective defenses. Its situation in the tropics spared it also from Pleistocene glaciations and the climate has not changed much.

There are large gaps in human knowledge about African invertebrates. East Africa has a rich coral fauna with about 400 known species. More than 400 species of echinoderms and 500 species of Bryozoa live there too, as well as one Cubozoan species (Carybdea alata). Of nematodes, the Onchocerca volvulus, Necator americanus, Wuchereria bancrofti and Dracunculus medinensis are human parasites. Some of important plant-parasitic nematodes of crops include Meloidogyne, Pratylenchus, Hirschmanniella, Radopholus, Scutellonema and Helicotylenchus. Of the few Onychophorans, Peripatopsis and Opisthopatus live in Africa. Greatest diversity of freshwater mollusks is found in East African lakes. Of marine snails, less diversity is present in Atlantic coast, more in tropical Western Indian Ocean region (over 3,000 species of gastropods with 81 endemic species). Cowry shells have been used as a money by native Africans. The land snail fauna is especially rich in Afromontane regions, and there are some endemic families in Africa (e.g. Achatinidae, Chlamydephoridae) but other tropical families are common too (Charopidae, Streptaxidae, Cyclophoridae, Subulinidae, Rhytididae). 156 tardigrade species have been found, and about 8,000 species of arachnids. The African millipede Archispirostreptus gigas is one of the largest in the world. 20 genera of freshwater crabs are present.

The soil animal communities tropical Africa are poorly known. A few ecological studies have been undertaken on macrofauna, mainly in West Africa. Earthworms are being extensively studied in West and South Africa.

Approximately 100,000 species of insects have been described from Sub-Saharan Africa, but there are very few overviews of the fauna as a whole (it has been estimated that the African insects make up about 10-20% of the global insect species richness, and about 15% of new species descriptions come from Afrotropics). The only endemic African insect order is Mantophasmatodea.