Africa is the world's second-largest and second-most-populous continent,after Asia.At about 30.2 million km² (11.7 million sq mi) including adjacent islands,it covers 6% of the Earth's total surface area and 20.4% of the total land area.[2] With 1.0 billion people (as of 2009,see table),it accounts for about 14.72% of the world's human population.
The continent is surrounded by the Mediterranean Sea to the north,both the Suez Canal and the Red Sea along the Sinai Peninsula to the northeast,the Indian Ocean to the southeast,and the Atlantic Ocean to the west.The continent includes Madagascar and various archipelagoes.It has 54 fully recognized sovereign states ("countries"),9 territories and three de facto states with limited recognition.[3]
Africa,particularly central Eastern Africa,is widely regarded within the scientific community to be the origin of humans and the Hominidae clade (great apes),as evidenced by the discovery of the earliest hominids and their ancestors,as well as later ones that have been dated to around seven million years ago – including Sahelanthropus tchadensis,Australopithecus africanus,A.afarensis,Homo erectus,H.habilis and H.ergaster – with the earliest Homo sapiens (modern human) found in Ethiopia being dated to circa 200,000 years ago.[4]
Africa straddles the equator and encompasses numerous climate areas; it is the only continent to stretch from the northern temperate to southern temperate zones.[5] The African expected economic growth rate is at about 5.0% for 2010 and 5.5% in 2011.
ain article:Geography of Africa
Africa is the largest of the three great southward projections from the largest landmass of the Earth.Separated from Europe by the Mediterranean Sea,it is joined to Asia at its northeast extremity by the Isthmus of Suez (transected by the Suez Canal),163 km (101 mi) wide.[53] (Geopolitically,Egypt's Sinai Peninsula east of the Suez Canal is often considered part of Africa,as well.)[54]
Biomes of Africa.
From the most northerly point,Ras ben Sakka in Tunisia (37°21' N),to the most southerly point,Cape Agulhas in South Africa (34°51'15" S),is a distance of approximately 8,000 km (5,000 mi);[55] from Cape Verde,17°33'22" W,the westernmost point,to Ras Hafun in Somalia,51°27'52" E,the most easterly projection,is a distance of approximately 7,400 km (4,600 mi).[56] The coastline is 26,000 km (16,000 mi) long,and the absence of deep indentations of the shore is illustrated by the fact that Europe,which covers only 10,400,000 km2 (4,000,000 sq mi) – about a third of the surface of Africa – has a coastline of 32,000 km (20,000 mi).[56]
Africa's largest country is Algeria,and its smallest country is the Seychelles,an archipelago off the east coast.[57] The smallest nation on the continental mainland is The Gambia.
According to the ancient Romans,Africa lay to the west of Egypt,while "Asia" was used to refer to Anatolia and lands to the east.A definite line was drawn between the two continents by the geographer Ptolemy (85–165 AD),indicating Alexandria along the Prime Meridian and making the isthmus of Suez and the Red Sea the boundary between Asia and Africa.As Europeans came to understand the real extent of the continent,the idea of Africa expanded with their knowledge.
Geologically,Africa includes the Arabian Peninsula; the Zagros Mountains of Iran and the Anatolian Plateau of Turkey mark where the African Plate collided with Eurasia.The Afrotropic ecozone and the Saharo-Arabian desert to its north unite the region biogeographically,and the Afro-Asiatic language family unites the north linguistically.
