Africa is the world's second-largest and second-most-populous continent. At about 30.2 million km2 (11.7 million sq mi) including adjacent islands, it covers six percent of Earth's total surface area and 20.4 percent of its total land area. With 1.1 billion people as of 2013, it accounts for about 15% of the world's human population.
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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 archipelagos. It has 54 fully recognized sovereign states (or countries), nine territories and two de facto independent states with limited or no recognition.[3]
Africa's population is the youngest amongst all the continents;[4][5] the median age in 2012 was 19.7, when the worldwide median age was 30.4.[6] Algeria is Africa's largest country by area, and Nigeria by population. Africa, particularly central Eastern Africa, is widely accepted as the place of 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.[7] Africa straddles the equator and encompasses numerous climate areas; it is the only continent to stretch from the northern temperate to southern temperate zones.
Economic inequality across countries has been declining for decades. China’s economic boom has been a big reason, along with technology that has brought energy and clean water to poorer countries.
The likelihood that a woman in sub-Saharan Africa has HIV today is linked to whether her country was once colonized by Britain or a continental European country, according to a June 2018 study published in American Economic Review.
For coastal communities threatened by global warming, the challenge can be sketched with two questions: How much will the waters surge and where will the inundation be worst?
“Sustainability” is a term that is frequently thrown around rather loosely, but its use tends to be restricted to specific practices or areas — sustainable urbanism, agriculture or energy, for example. While there has long been concern over rising human population levels and resource consumption, the larger question of where the ultimate limits might be — the Earth is a fixed size, after all — has been subject to as much rhetoric-charged debate as considered research.
Economists who study international development often focus on measuring countries’ aggregate and per-capita volumes of output. However, the mix of industries and products — the diversity within an economy — is an important and under-appreciated variable in predicting potential growth, according to scholars at the Center for International Development at the Harvard Kennedy School.
Information communication technology (ICT) such as computers and cell phones has proliferated throughout the world, and many developing nations are consuming them at an increasing rate. Moreover, as such goods become technologically outdated in wealthier nations, they are often shipped to developing countries for refurbishment, recycling or disposal. However, such countries are sometimes ill-equipped to deal with the parts found in many products in an ecologically sound manner.
