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Wild Africa
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The map below is divided into the six major habitats of the African continent;
Mountains, Savannah, Deserts, Coasts, Jungle, Lakes & Rivers.
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Mountains
Africa's highest mountain is the towering Kilimanjaro at 5960m. The mountain lies on the equator but is topped with glaciers. It is thought that due to global warming these will be gone in less than 15 years. Formed by a folding of the earth's crust, Africa's only fold mountains are found in the far north (the Atlas Mountains) and south of the continent (Cape Folded Mountains). The Ethiopian Highlands, the Hoggar Mountains of the Sahara and the Ruwenzoris are all the result of volcanic activity. Mountain habitats are determined by altitude and levels of moisture and often each zone can be quite different from the higher and lower zones on either side.
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Savannah
Savannahs range from open woodland to vast areas of park-like grassland and can be moist and lush or almost desert. They are always found in warm or hot climates where the annual rainfall is from about 50.8 to 127 cm per year. The dominant vegetation is grass. It is a highly adaptable species that can grow in virtually all soil types including those with extremely low nutrients and will tolerate seasons of drought and even fire. Vast numbers of mammals are able to live here because they all have a special niche. Some are migratory preferring newly sprouted grass while others will only eat grass that has been nibbled down. Others eat those that eat the grass. Almost half of the continent of Africa, about 13 million square km, is covered by Savannah.
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Deserts
Africa contains both the world's oldest desert (the Namib) and the world's largest desert (the Sahara). A desert is defined as an area that receives less than 100 mm of rain per year. In order to survive these sort of conditions, animals and plants have to be adapted to extremes of temperature and very little water. Many species of desert plant produce seeds which can lie dormant for years while waiting for the rains to arrive. Often animals in deserts are nocturnal because at night temperatures are cooler for foraging and hunting. Africa's other major arid zones are the Kalahari and Karoo Deserts of Southern Africa. They receive between 100-250mm of rain a year so the vegetation here is much more abundant.
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Coasts
Of Africa's 48 nations, 33 have coastal frontage and the remaining 15 are land-locked. The direction and the temperature of the currents that wash Africa's shores determine both the coastal and interior climates. The east coast is governed by a system of warm currents, the West, by two cold currents (the Canaries and the Benguela) plus the warm Guinea current which bathes the shores of the Gulf of Guinea. With climate change over the millenia, sea levels have risen and fallen and current levels were only reached as little as 5000 years ago. Southern Africa's rocky shores have been eroded by waves and weather to create a dramatic coast of headlands. Waves and currents create vast sandy lagoons and spits on the West African coast with the Red Sea providing perfect conditions for coral growth.
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Jungle
A million years ago, forest covered most of west and central Africa. As the climate became drier and colder (due to the ice age) the forest contracted to highland refuges where forest species survived and their evolution continued. When the ice retreated, the forest expanded and was re-colonised from these small pockets of forest. Today we are in a warm, moist phase and the forest is probably at it's greatest extent. Living in the forest means adapting to a limited food supply. The diet of the forest elephant is strikingly different to that of their savannah cousins; fruit and leaves roots and seeds, a diet more akin to that of a gorilla. Thirty kinds of trees depend entirely on these elephants to disperse their seeds.
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Lakes and Rivers
Africa's fresh water is carried across the continent by the world's longest river (the Nile), dropped over the world's widest single curtain of falling water (Victoria Falls) and stored in the world's second largest freshwater lake (Lake Victoria). In spite of these records, more than half of Africa receives less than 50 cm of rain per year and 80% of this water evaporates leaving only 20% available to life. So where water does gather, it provides a magnet to wildlife. Animals have learnt to take advantage of these seasonal opportunities; like tadpole shrimps that can survive as eggs in the dry riverbed for as long as 7 years. Here they wait for rain to fall and reconstitute them. Rain that falls in the highlands often takes 3-4 months to travel downstream to lower lying areas.
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