Hojas

Africa
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.  With 1.0 billion people (as of 2009, see table) in 61 territories, it accounts for about 14.72% of the world's human population.
The continent issurrounded 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 has 54sovereign states, including Madagascar and various island groups.
Africa, particularly central Eastern Africa, is widely regarded within the scientific community to be the originof 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 Ethiopiabeing datedto circa 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. The African expected economic growth rate is at about 5.0% for 2010 and 5.5% in 2011.
Africa is the largest of the three great southward projections from the largest landmass of the Earth. Separated fromEurope 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). he 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 only10,400,000 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 Algeria, 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 torefer to Anatolia and lands to the east. A definite line was drawn between the two continents by the geographer Ptolemy (85–165 AD), indicating Alexandriaalong 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, Africaincludes 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.

Climate
The climate of Africa ranges from tropical to subarctic on itshighest peaks. Its northern half is primarily desert or arid, while its central and southern areas contain both savanna plains and very dense jungle (rainforest) regions. In between, there is a convergence where vegetation patterns such as sahel, and steppe dominate. Africa is the hottest continent on earth; drylands and deserts comprise 60% of the entire land surface. The record for the highest...