The Afrotropic is one of eight ecozones found on Earth. It includes Africa (south of the Sahara Desert), the southern and eastern borders of the Arabian Peninsula, the island of Madagascar, southern Iran and outermost southwestern Pakistan, and the islands of the western Indian Ocean. The Afrotropic was previously known as the Ethiopian Zone. The Afrotropic has mostly a tropical climate, except for Africa’s far-southern region. The Afrotropic borders the Palearctic ecozone to the north, which includes northern Africa and milder Eurasia.
Many different and diverse regions make up the Afrotropic ecozone. South of the Sahara, two belts of tropical grassland and savanna run east and west across the continent, from the Atlantic Ocean to the Ethiopian Highlands. The Sahel belt is a transitional zone that lays directly south of the Sahara. It is made up of semi-arid short grassland and Acacia savanna. Further south, in the Sudan (Sudanian Savanna), there are taller grasslands and savannas where the rainfall is greater. There are two great flooded grasslands in the Sudanian Savanna, the Sudd wetland in the Sudan, and the Niger Inland Delta in Mali.
The forest zone (a belt of lowland moist tropical broadleaf forests) runs across much of equatorial Africa’s intertropical convergence zone (North-East and South-East trade wind junctions). The Upper Guinean forests of West Africa extend along the coast of Guinea to Togo. The Dahomey Gap, a region of forested savanna that stretches to the coast, divides the Upper Guinean forests from the Lower Guinean forests. The Lower Guinean forests extend along the Gulf of Guinea from eastern Benin through Cameroon and Gabon to the western Democratic Republic of Congo. The Congolian forest of the Congo Basin in central Africa is the largest tropical forest zone in Africa. A tropical broadleaf forest belt also runs along the Indian Ocean from Somalia to South Africa.
Other regions within the Afrotropic include the Acacia-Commiphora grasslands, the Serengeti, Ethiopian Highlands, Albertine rift Montane forests, East African montane forests, Eastern Arc forests, Miombo woodlands, Zambezian Mopane, Baikiaea woodlands, Bushveld, Namib Desert, and Kalahari Desert. The Afromontane region, which extends from the Ethiopian Highlands to the Drakensberg Mountains of South Africa, includes the Great Rift Valley. It is home to unique flora, including Podocarpus, Afrocarpus, Lobelias and Senecios.
The Cape floristic region (at Africa’s southern tip) is a Mediterranean climate zone that is home to a wide variety of endemic plant families, especially Proteaceae which are also found in Australasia. Madagascar and the neighboring islands form a distinct sub-region of the Afrotropic ecozone where numerous endemic taxa (phylum, genus, species, etc.) are found. There are several important biospheres associated with Madagascar. Biodiversity and endemic ratios are extremely high in these biospheres.
The Afrotropic ecozone is home to a wide array of endemic plant families. Ten endemic families are found in Madagascar and the Indian Ocean Islands, of which eight are found solely on Madagascar. There are twelve plant families endemic to South Africa, of which five are endemic to Cape floristic province. The East African Great Lakes (Victoria, Malawi, and Tanganyika) are home to many freshwater fish species, including cichlids. The West African coastal rivers region covers only a small portion of West Africa, but 322 of West African’s fish species are found there. 247 species are restricted there and 129 species are even further restricted to small ranges. The central rivers region is comprised of 194 fish species, with 119 endemic species.
There are many bird families that are native to the Afrotropic, including ostriches, sunbirds, guineafowl, mousebirds, and the Secretary Bird. Several passerine families are limited to the Afrotropic as well, including rock-jumpers and rock-fowl. There are 3 endemic mammal orders found in the Afrotropic. These are the aardvarks, tenrecs and golden moles, and elephant shrews. The East African plains is well known for the diversity of large mammals found there. Four species of Great Apes are endemic to Africa: the Western Gorilla, Eastern Gorilla, Common Chimpanzee, and the Bonobo.
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