According to countryaah, Africa is the part of the world in which the past conditions of plant and animal life have been preserved most intact, despite the alternating degradations caused by the different climatic cycles that have caused plant associations to move from South to North, and vice versa. The scarce human population and the particular attitude of African cultures that have always tried to respect the ecological balance, as a fact also determined in a religious and ritualistic sense, also contributed to the conservative character of the African environment. Plant and animal forms are present in a vast range of peculiar species which are the result of a thousand-year biological adaptation that began from the time when Africa separated from the other continental masses. Currently the Saharan desert acts as the main dividing element of the more typically African species, while Madagascar forms an area of its own, very special and with few elements in common with the neighboring continent. The Saharan region, in relation to climate change, however, has always been a very mobile border: the fauna now settled in the Sudanese belt lived in the past in the northernmost desert areas, as is also documented by the rock engravings. This shows how, in a continent so open and devoid of dividing elements, the factor that regulates and determines the biological areas is essentially rainfall: this happens within fairly clear limits, so much so that the isoieties provide the main delimiting elements of the different environments.
The various environments into which the continent is divided correspond, in a zonal sense, to the equatorial rainforest, the arboreal savannah, the shrub savannah, the steppe and the desert, according to a succession that is repeated in the southern and boreal part. Beyond the desert, the steppes, shrub areas and finally, at the extremes, the Mediterranean areas resume. The rainforest extends into the Congo Basin and the Guinean belt best exposed to oceanic influences. It often appears degraded (grasses, palms of the genus Borassus or various other gregarious species of the primary forest grow there) and takes on its greatest luxuriance on the Atlantic facade of Cameroon and Congo. It is generally three-story, evergreen, with lianas and epiphytes, and has a large number of species, including precious essences such as mahogany, ebony and okoumé (widespread in Gabon), as well as useful plants such as the oil palm. Vast mangrove formations clutter the river mouths. With the absence of equatorial conditions, the forest gradually becomes impoverished and continues only along the river courses (tunnel forest), creating dense green bands that adapt to the river network. Among them are the first savannah formations, mainly arboreal (forest-park), with grassy clearings. The species are quantitatively reduced and among them appear both those of an equatorial environment and those of a tropical environment. The savannah (broussein French and bush in English) becomes more and more sparse, assuming its characteristic appearance, with spaced tree formations, shrubs and grassy clearings more or less extensive. Among the arboreal individuals the baobab (Adansonia digitata) dominates, a species that has wide margins of adaptability to the long dry season typical of the savannah environment. There are also numerous thorny plants and those with leathery leaves, which represent as many environmental adaptations; the savannas are then the domain of the acacias, which are found in numerous species, including useful ones, such as the acacia gumiferous (Acacia senegal, hashab in Arabic). Proceeding still towards less rainy areas, the species become accentuated xerophilous, shrub species predominate, while the arboreal forms (mimosas, tamarisks, tamarinds) look for the banks or the shores of temporary rivers. In the pre-desert areas the tree species become dwarf, degraded, and there are grassy surfaces formed by tufts of grasses such as alpha and essences such as esparto, artemisia etc., species with a short vegetative cycle characteristic of the sahel . In the desert, plant life occurs only along the uidians and at the base of the mountainous slopes; however, between the Saharan desert and the southern one (Kalahari) the species are different. In the first there are numerous Euphorbiacee, in addition there are relict species typical of the Mediterranean area (the cypresses of Tassili, the wild olive tree of Jabel Marrah) settled in times when the region was rainier. In the oases the date palm dominates, in the shade of which horticultural crops can be practiced thanks to irrigation. Particular plant species are found in high Africa (here too many euphorbias) and on the equatorial mountains, where heather and different species of both southern and northern origin dominate.
Animal life varies considerably in relation to these environments. It is limited, as a number of species, in the rainforest belt, where among the mammals the most peculiar species are the monkeys, among which the gorilla is characteristic and rare (some subspecies of this animal, such as the Cross River gorilla is at serious risk of extinction); on the other hand, there are numerous insects, including the tsetse fly, which has had so much influence in keeping the population sparse in this African environment. The savannas, on the other hand, are very rich in mammals, and particularly large African mammals, which find abundant pasture in the vast grassy spaces and which represent the prey of felines (lions and leopards), typically African. The most abundant species are those of ungulates (antelopes, gazelles, zebras, etc.) which also extend towards the arid, sub-desert belts, sometimes with seasonal migrations in search of pastures and springs. The elephants and rhinos instead look for the savannah environments where there are rivers or ponds. Among the insects of the savannahs, termite is very common, which is responsible for the termite mounds, essential elements of the African landscape. With the Sahara we enter the domain of domestic animals introduced by man in recent times, such as the dromedary, one of the factors of Islamic expansion in Africa and of the human conquest of the desert.