Geography

Africa is the largest of the three great southward projections from the main mass of the Earth's exposed surface. 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 miles) wide. (Geopolitically, Egypt's Sinai Peninsula east of the Suez Canal is often considered part of Africa, as well.) 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 miles); 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 miles). The coastline is 26,000 km (16,100 miles) long, and the absence of deep indentations of the shore is illustrated by the fact that Europe, which covers only 10,400,000 km² (4,010,000 square miles) – about a third of the surface of Africa – has a coastline of 32,000 km (19,800 miles).

Africa's largest country is Sudan, and its smallest country is the Seychelles, an archipelago off the east coast. 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.

Africa

is the world's second-largest and second most-populous continent, after Asia. At about 30,221,532 km² (11,668,545 sq mi) including adjacent islands, it covers 6% of the Earth's total surface area, and 20.4% of the total land area. With more than 900 million people (as of 2005) in 61 territories, it accounts for about 14% of the world's human population. The continent is surrounded by the Mediterranean Sea to the north, the Suez Canal and the Red Sea to the northeast, the Indian Ocean to the southeast, and the Atlantic Ocean to the west. There are 46 countries including Madagascar, and 53 including all the island groups.

Africa, particularly central eastern Africa, is widely regarded within the scientific community to be the origin of humans and the Hominidae tree (great apes), as evidenced by the discovery of the earliest hominids and their possible 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 (human) found in Ethiopia being dated to ca. 200,000 years ago.

Africa straddles the equator and encompasses numerous climate areas; it is the only continent to stretch from the northern temperate to southern temperate zones.Because of the lack of natural regular precipitation and irrigation as well as glaciers or mountain aquifer systems, there is no natural moderating effect on the climate except near the coasts.