Genetic measurements indicate that the ape lineage which would lead to Homo sapiens diverged from the lineage that would lead to chimpanzees and bonobos, the closest living relatives of modern humans, around 4.6 to 6.2 million years ago. Anatomically modern humans arose in Africa about 300,000 years ago, and reached behavioural modernity about 50,000 years ago.
Modern humans spread rapidly from Africa into the frost-free zones of Europe and Asia around 60,000 years ago. The rapid expansion of humankind to North America and Oceania took place at the climax of the most recent ice age, when temperate regions of today were extremely inhospitable. Yet, humans had colonized nearly all the ice-free parts of the globe by the end of the Ice Age, some 12,000 years ago. Other hominids such as Homo erectus had been using simple wood and stone tools for millennia, but as time progressed, tools became far more refined and complex.
Perhaps as early as 1.8 million years ago, but certainly by 500,000 years ago, humans began using fire for heat and cooking. They also developed language in the Paleolithic period and a conceptual repertoire that included systematic burial of the dead and adornment of the living. Early artistic expression can be found in the form of cave paintings and sculptures made from ivory, stone, and bone, showing a spirituality generally interpreted as animism, or even shamanism. During this period, all humans lived as hunter-gatherers, and were generally nomadic. Archaeological and genetic data suggest that the source populations of Paleolithic hunter-gatherers survived in sparsely wooded areas and dispersed through areas of high primary productivity while avoiding dense forest cover.
Rise of civilization
The Neolithic Revolution, beginning around 10,000 BCE, saw the development of agriculture, which fundamentally changed the human lifestyle. Farming developed around 10,000 BCE in the Middle East, around 7000 BCE in what is now China, around 6000 BCE in the Indus Valley and Europe, and around 4000 BCE in the Americas. Cultivation of cereal crops and the domestication of animals occurred around 8500 BCE in the Middle East, where wheat and barley were the first crops and sheep and goats were domesticated. In the Indus Valley, crops were cultivated by 6000 BCE, along with domesticated cattle. The Yellow River valley in China cultivated millet and other cereal crops by about 7000 BCE, but the Yangtze River valley domesticated rice earlier, by at least 8000 BCE. In the Americas, sunflowers were cultivated by about 4000 BCE, and maize and beans were domesticated in Central America by 3500 BCE. Potatoes were first cultivated in the Andes Mountains of South America, where the llama was also domesticated. Metal-working, starting with copper around 6000 BCE, was first used for tools and ornaments. Gold soon followed, with its main use being for ornaments. The need for metal ores stimulated trade, as many of the areas of early human settlement were lacking in ores. Bronze, an alloy of copper and tin, was first known from around 2500 BCE, but did not become widely used until much later.
Though early proto-cities appeared at Jericho and Catal Huyuk around 6000 BCE, the first civilizations did not emerge until around 3000 BCE in Egypt and Mesopotamia. These cultures gave birth to the invention of the wheel, mathematics, bronze-working, sailing boats, the pottery wheel, woven cloth, construction of monumental buildings, and writing. Writing developed independently and at different times in five areas of the world: Egypt (c. 3200 BCE), India (c. 3200 BCE), Mesopotamia (c. 3000 BCE), China (c. 1600 BCE), and Mesoamerica (c. 600 BCE).
Farming permitted far denser populations, which in time organized into states. Agriculture also created food surpluses that could support people not directly engaged in food production. The development of agriculture permitted the creation of the first cities. These were centres of trade, manufacturing and political power. Cities established a symbiosis with their surrounding countrysides, absorbing agricultural products and providing, in return, manufactured goods and varying degrees of military control and protection.
The development of cities was synonymous with the rise of civilization.[a] Early civilizations arose first in Lower Mesopotamia (3000 BCE), followed by Egyptian civilization along the Nile River (3000 BCE), the Harappan civilization in the Indus River Valley (in present-day India and Pakistan; 2500 BCE), and Chinese civilization along the Yellow and Yangtze Rivers (2200 BCE). These societies developed a number of unifying characteristics, including a central government, a complex economy and social structure, sophisticated language and writing systems, and distinct cultures and religions. Writing facilitated the administration of cities, the expression of ideas, and the preservation of information.
Entities such as the Sun, Moon, Earth, sky, and sea were often deified.Shrines developed, which evolved into temple establishments, complete with a complex hierarchy of priests and priestesses and other functionaries. Typical of the Neolithic was a tendency to worship anthropomorphic deities. Among the earliest surviving written religious scriptures are the Egyptian Pyramid Texts, the oldest of which date to between 2400 and 2300 BCE.