Afrotropic ecozone

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See Tropical Africa, Sub-Saharan Africa for other aspects.

The Afrotropic is one of the Earth's eight ecozones. It includes Africa south of the Sahara Desert, the southern and eastern fringes of the Arabian Peninsula, the island of Madagascar, southern Iran and extreme southwestern Pakistan, and the islands of the western Indian Ocean. It was formerly known as the Ethiopian Zone or Ethiopian Region.

The Afrotropic Ecozone

Major ecological regions[edit]

Most of the Afrotropic, with the exception of Africa's southern tip, has a tropical climate. A broad belt of deserts, including the Atlantic and Sahara deserts of northern Africa and the Arabian Desert of the Arabian Peninsula, separate the Afrotropic from the Palearctic ecozone, which includes northern Africa and temperate Eurasia.

Sahel and Sudan[edit]

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. Immediately south of the Sahara lies the Sahel belt, a transitional zone of semi-arid short grassland and Acacia savanna. Rainfall increases further south in the Sudanian Savanna, also known simply as the Sudan, a belt of taller grasslands and savannas. The Sudanian Savanna is home to two great flooded grasslands, the Sudd wetland in South Sudan, and the Niger Inland Delta in Mali. The forest-savanna mosaic is a transitional zone between the grasslands and the belt of tropical moist broadleaf forests near the equator.

Southern Arabian woodlands[edit]

South Arabia, expressed as being mostly Yemen and parts of western Oman and southwestern Saudi Arabia, has few permanent forests. Some of the notable are Jabal Bura', Jabal Raymah, and Jabal Badaj in the Yemeni highland escarpment, and the seasonal forests in eastern Yemen and the Dhofar region of Oman. Other woodlands scatter the land and are very small and are predominately juniper or acacia forests.

Forest zone[edit]

The forest zone, a belt of lowland tropical moist broadleaf forests, runs across most of equatorial Africa's intertropical convergence zone. The Upper Guinean forests of West Africa extend along the coast from Guinea to Togo. The Dahomey Gap, a zone of forest-savanna mosaic that reaches to the coast, separates the Upper Guinean forests from the Lower Guinean forests, which extend along the Gulf of Guinea from eastern Benin through Cameroon and Gabon to the western Democratic Republic of the Congo. The largest tropical forest zone in Africa are the Congolian forests of the Congo Basin in Central Africa. A belt of tropical moist broadleaf forest also runs along the Indian Ocean coast, from southern Somalia to South Africa.

East African grasslands and savannas[edit]

Eastern Africa's highlands[edit]

Afromontane region, from the Ethiopian Highlands to the Drakensberg Mountains of South Africa, including the East African Rift. Distinctive flora, including Podocarpus and Afrocarpus, as well as giant Lobelias and Senecios.

Southern African woodlands, savannas, and grasslands[edit]

Deserts of southern Africa[edit]

Cape floristic region[edit]

The Cape floristic region, at Africa's southern tip, is a Mediterranean climate region that is home to a significant number of endemic taxa, as well as to plant families like the proteas (Proteaceae) that are also found in the Australasia ecozone.

Madagascar and the Indian Ocean islands[edit]

Madagascar and neighboring islands form a distinctive sub-region of the ecozone, with numerous endemic taxa like the lemurs. Madagascar and the Seychelles are old pieces of the ancient supercontinent of Gondwana, and broke away from Africa millions of years ago. Other Indian ocean islands, like the Comoros and Mascarene Islands, are volcanic islands that formed more recently. Madagascar contains several important biospheres, as its Biodiversity and ratio of endemicism is extremely high.

Endemic plants and animals[edit]

Plants[edit]

The Afrotropic ecozone is home to a number of endemic plant families. Madagascar and the Indian Ocean Islands are home to ten endemic families of flowering plants; eight are endemic to Madagascar (Asteropeiaceae, Didymelaceae, Didiereaceae, Kaliphoraceae, Melanophyllaceae, Physenaceae, Sarcolaenaceae, and Sphaerosepalaceae), one to Seychelles (Mesdusagynaceae) and one to the Mascarene Islands (Psiloxylaceae). Twelve plant families are endemic or nearly endemic to South Africa (including Curtisiaceae, Heteropyxidaceae, Penaeaceae, Psiloxylaceae and Rhynchocalycaceae) of which five are endemic to the Cape floristic province (including Grubbiaceae). Other endemic Afrotropic families include Barbeyaceae, Montiniaceae, Myrothamnaceae and Oliniaceae.

Animals[edit]

The East African Great Lakes (Victoria, Malawi, and Tanganyika) are the center of biodiversity of many freshwater fishes, especially cichlids (they harbor more than two-thirds of the estimated 2,000 species in the family).[1] The West African coastal rivers region covers only a fraction of West Africa, but harbours 322 of West African’s fish species, with 247 restricted to this area and 129 restricted even to smaller ranges. The central rivers fauna comprises 194 fish species, with 119 endemics and only 33 restricted to small areas.[2]

The Afrotropic has various endemic bird families, including ostriches (Struthionidae), sunbirds, Secretary bird (Sagittariidae), guineafowl (Numididae), and mousebirds (Coliidae). Also, several families of passerines are limited to the Afrotropics; These include rock-jumpers (Chaetopidae) and rockfowl (Picathartidae).

Africa has three endemic orders of mammals, the Tubulidentata (aardvarks), Afrosoricida (tenrecs and golden moles), and Macroscelidea (elephant shrews). The East-African plains are well known for their diversity of large mammals.

Four species of Great Apes (Hominidae) are endemic to Africa: both species of Gorilla (Western Gorilla, Gorilla gorilla, and Eastern Gorilla, Gorilla beringei) and both species of Chimpanzee (Common Chimpanzee, Pan troglodytes, and Bonobo, Pan paniscus). Humans and their ancestors originated in Africa.

Afrotropic Terrestrial Ecoregions[edit]

Albertine Rift montane forestsDemocratic Republic of the Congo, Burundi, Rwanda, Tanzania, Uganda
Atlantic Equatorial coastal forestsAngola, Cameroon, Democratic Republic of the Congo, Republic of the Congo, Equatorial Guinea, Gabon
Cameroonian Highlands forestsCameroon, Nigeria
Central Congolian lowland forestsDemocratic Republic of the Congo
Comoros forestsComoros
Cross-Niger transition forestsNigeria
Cross-Sanaga-Bioko coastal forestsCameroon, Equatorial Guinea, Nigeria
East African montane forestsKenya, South Sudan, Tanzania, Uganda
Eastern Arc forestsTanzania, Kenya
Eastern Congolian swamp forestsDemocratic Republic of the Congo
Eastern Guinean forestsBenin, Ghana, Ivory Coast, Togo
Ethiopian montane forestsEritrea, Ethiopia, Somalia, Sudan
Granitic Seychelles forestsSeychelles
Guinean montane forestsGuinea, Ivory Coast, Liberia, Sierra Leone
Knysna-Amatole montane forestsSouth Africa
KwaZulu-Cape coastal forest mosaicSouth Africa
Madagascar lowland forestsMadagascar
Madagascar subhumid forestsMadagascar
Maputaland coastal forest mosaicMozambique, Swaziland, South Africa
Mascarene forestsMauritius, Réunion
Mount Cameroon and Bioko montane forestsCameroon, Equatorial Guinea
Niger Delta swamp forestsNigeria
Nigerian lowland forestsBenin, Nigeria
Northeastern Congolian lowland forestsCameroon, Central African Republic, Gabon, Republic of the Congo
Northern Zanzibar-Inhambane coastal forest mosaicKenya, Somalia, Tanzania
Northwestern Congolian lowland forestsCameroon, Central African Republic, Gabon, Republic of the Congo
São Tomé, Príncipe, and Annobón moist lowland forestsEquatorial Guinea, São Tomé and Príncipe
Southern Zanzibar-Inhambane coastal forest mosaicMalawi, Mozambique, Tanzania, Zimbabwe
Western Congolian swamp forestsDemocratic Republic of the Congo, Republic of the Congo
Western Guinean lowland forestsGuinea, Ivory Coast, Liberia, Sierra Leone
Cape Verde Islands dry forestsCape Verde
Madagascar dry deciduous forestsMadagascar
Zambezian Cryptosepalum dry forestsZambia, Angola
Angolan Miombo woodlandsAngola
Angolan Mopane woodlandsAngola, Namibia
Ascension scrub and grasslandsAscension Island
Central Zambezian Miombo woodlandsAngola, Burundi, Democratic Republic of the Congo, Malawi, Tanzania, Zambia
East Sudanian savannaCameroon, Central African Republic, Chad, Democratic Republic of the Congo, Eritrea, Ethiopia South Sudan, Sudan, Uganda
Eastern Miombo woodlandsMozambique, Tanzania
Guinean forest-savanna mosaicBenin, Burkina Faso, Cameroon, Gambia, Ghana, Guinea, Guinea Bissau, Ivory Coast, Nigeria, Senegal, Togo
Itigi-Sumbu thicketTanzania, Zambia
Kalahari Acacia-Baikiaea woodlandsBotswana, Namibia, South Africa, Zimbabwe
Mandara Plateau mosaicCameroon, Nigeria
Northern Acacia-Commiphora bushlands and thicketsEthiopia, Kenya, South Sudan, Uganda
Northern Congolian forest-savanna mosaicCameroon, Central African Republic, Democratic Republic of the Congo, South Sudan, Uganda
Sahelian Acacia savannaBurkina Faso, Cameroon, Chad, Eritrea, Ethiopia, Mali, Mauritania, Niger, Nigeria, Senegal, South Sudan, Sudan
SerengetiKenya, Tanzania
Somali Acacia-Commiphora bushlands and thicketsEritrea, Ethiopia, Kenya, Somalia
Southern Acacia-Commiphora bushlands and thicketsKenya, Tanzania
Southern Africa bushveldBotswana, South Africa, Zimbabwe
Southern Congolian forest-savanna mosaicAngola, Democratic Republic of the Congo
Southern Miombo woodlandsMalawi, Mozambique, Zambia, Zimbabwe
Saint Helena scrub and woodlandsSaint Helena
Victoria Basin forest-savanna mosaicBurundi, Ethiopia, Kenya, Rwanda, South Sudan, Tanzania, Uganda
West Sudanian savannaBenin, Burkina Faso, Gambia, Ghana, Guinea, Ivory Coast, Niger, Nigeria, Senegal
Western Congolian forest-savanna mosaicAngola, Democratic Republic of the Congo, Republic of the Congo
Western Zambezian grasslandsAngola, Zambia
Zambezian and Mopane woodlandsBotswana, Malawi, Mozambique, Namibia, South Africa, Swaziland, Zambia, Zimbabwe
Zambezian Baikiaea woodlandsAngola, Botswana, Namibia, Zambia, Zimbabwe
Al Hajar Al Gharbi montane woodlandsOman
Amsterdam and Saint-Paul Islands temperate grasslandsAmsterdam Island, Saint-Paul Island
Tristan da Cunha-Gough Islands shrub and grasslandsTristan da Cunha, Gough Island
East African halophyticsKenya, Tanzania
Etosha Pan halophyticsNamibia
Inner Niger Delta flooded savannaMali
Lake Chad flooded savannaCameroon, Chad, Nigeria
Saharan flooded grasslandsSouth Sudan
Zambezian coastal flooded savannaMozambique
Zambezian flooded grasslandsAngola, Botswana, Democratic Republic of the Congo, Malawi, Mozambique, Tanzania, Zambia
Zambezian halophyticsBotswana
Angolan montane forest-grassland mosaicAngola
Angolan Scarp savanna and woodlandsAngola
Drakensberg alti-montane grasslands and woodlandsLesotho, South Africa
Drakensberg montane grasslands, woodlands and forestsLesotho, South Africa, Swaziland
East African montane moorlandsKenya, Sudan, Tanzania, Uganda
Eastern Zimbabwe montane forest-grassland mosaicMozambique, Zimbabwe
Ethiopian montane grasslands and woodlandsEthiopia, Sudan
Ethiopian montane moorlandsEthiopia, Sudan
Highveld grasslandsLesotho, South Africa
Jos Plateau forest-grassland mosaicNigeria
Madagascar ericoid thicketsMadagascar
Maputaland-Pondoland bushland and thicketsMozambique, South Africa, Swaziland
Ruwenzori-Virunga montane moorlandsDemocratic Republic of the Congo, Rwanda, Uganda
South Malawi montane forest-grassland mosaicMalawi, Mozambique
Southern Rift montane forest-grassland mosaicMalawi, Tanzania
Albany thicketsSouth Africa
Lowland fynbos and renosterveldSouth Africa
Montane fynbos and renosterveldSouth Africa
Aldabra Island xeric scrubSeychelles
Arabian Peninsula coastal fog desertOman, Saudi Arabia, Yemen
East Saharan montane xeric woodlandsChad, Sudan
Eritrean coastal desertDjibouti, Eritrea
Ethiopian xeric grasslands and shrublandsDjibouti, Eritrea, Ethiopia, Somalia, Sudan
Gulf of Oman desert and semi-desertOman, United Arab Emirates
Hobyo grasslands and shrublandsSomalia
Ile Europa and Bassas da India xeric scrubBassas da India, Europa
Kalahari xeric savannaBotswana, Namibia, South Africa
Kaokoveld desertAngola, Namibia
Madagascar spiny thicketsMadagascar
Madagascar succulent woodlandsMadagascar
Masai xeric grasslands and shrublandsEthiopia, Kenya
Nama KarooNamibia, South Africa
Namib desertNamibia
Namibian savanna woodlandsNamibia
Red Sea coastal desertEgypt, Sudan
Socotra Island xeric shrublandsYemen
Somali montane xeric woodlandsSomalia
Southwestern Arabian foothills savannaOman, Saudi Arabia, Yemen
Southwestern Arabian montane woodlandsSaudi Arabia, Yemen
Succulent KarooSouth Africa
Central African mangrovesAngola, Cameroon, Democratic Republic of the Congo, Equatorial Guinea, Gabon, Ghana, Nigeria
East African mangrovesKenya, Mozambique, Tanzania
Guinean mangrovesSenegal, Gambia, Guinea-Bissau, Guinea, Sierra Leone, Liberia, Ivory Coast
Madagascar mangrovesMadagascar
Southern Africa mangrovesMozambique, South Africa

See also[edit]

External links[edit]

References[edit]

  1. ^ I.P.Farias et al.,Total Evidence: Molecules, Morphology, and the Phylogenetics of Cichlid Fishes, Journal of Experimental Zoology (Mol Dev Evol) 288:76–92 (2000)
  2. ^ T.Moritz and K. E. Linsenmair, West African fish diversity – distribution patterns and possible conclusions for conservation strategies (in African Biodiversity: Molecules, Organisms, Ecosystems, Springer, 2001)