Saylor.org's Ancient Civilizations of the World/Origins of American Societies
The first people to settle North America are thought to have crossed over from Asia during the last Ice Age (roughly 15,000 years ago). Around this time, huge amounts of water froze into glaciers, the Bering Strait between Siberia and Alaska drained, and a wide, low, treeless plain called Beringia connected the two continents. The paleo-Indians moved south through a corridor between the ice sheets to settle the prairies. By 11,000 BCE they had reached the southern tip of South America. By this time, significant hunting activities were taking place in North America and many large mammals, such as the woolly mammoth, may have become extinct as a result of hunting and climate change. Once humans were established in Central America, they quickly became more sedentary, simple village structures evolving within a small time frame into far more complex societies. The archaeological evidence left by the Olmec and Zapotec in Central America, and the burial mounds of the Adena and Hopewell of the American Southeast reveal sophisticated societies.
The Early Hunter-Gatherers
The earliest peoples of North and Central America banded together in egalitarian, extended-family groups, living by hunting and gathering. They eventually become specialized and adapted to the continent's various ecological niches: plains, mountains, deserts, woodlands, river valleys, and coastal areas. Specifically, adapted spear points and other weaponry reveal the major prey species in different culture areas. The fine "Clovis" spearheads were used by plains hunters to kill bison, barbed harpoon heads were developed by coastal peoples for spearing marine creatures, and stone-tipped darts were thrown by the basin and mountain dwellers at the wildfowl which provided them with the bulk of their diet.
The First Farmers
Agriculture in North America emerged only gradually but proved revolutionary in its impact. Animal husbandry was largely absent, with only a few animals truly domesticated. Dogs, honeybees, and turkeys were the first animals to be domesticated in the Americas. In Central America, a few plants were cultivated as a supplement to hunting and gathering as early as 5000 BCE and new plants - especially corn, beans, and squash - were brought under cultivation and soon offered a more secure food source. Hunting bands became seasonally sedentary and then semi-sedentary, until between 2500 and 1400 BCE, when Central America was dominated by settled horticultural villages. Further north, the earliest crops served initially as supplements rather than as staples. Agriculture gradually became more important throughout the first millennium CE, with villagers becoming largely agricultural by the beginning of the second millennium.
Early Civilizations of Central America
With the establishment of village life, the earliest complex settlements occurred in the tropical lowlands from the Gulf of Mexico across the Isthmus of Tehuantepec to the Pacific coast of present-day Guatemala. Increasingly sophisticated societies were made possible by new crops and productive soils. The Olmec civilization emerged on the Gulf Coast c. 1500 BCE and flourished until c. 400 BCE. Slightly later than the Olmec, the Valley of Oaxaca witnessed the development of a sophisticated society, and by 500 BCE, complex chiefdoms or early states dominated the three valleys of central Oaxaca. At their juncture, the Zapotec built the hilltop city of Monte Alban which would dominate the region for over a millennium. In the highlands south of Yucatan, the Maya civilization was starting to emerge as early as 1000 BCE.
The Moundbuilders of the Eastern River Valleys
The Adena culture was found in the upper Ohio valley as early as 1000 BCE. Settlements were centered on burial mounds and extensive earthworks. Their grave goods included jewelry made from imported copper, carved tablets, and tubular pipes - which provide evidence of the early cultivation of tobacco. The Hopewell culture had emerged by c. 100 CE, and spread throughout the Mississippi Valley, sustained by small-scale agriculture. They created a complex and far-reaching trade network to source the many raw materials - including obsidian, mica, quartz, shells, teeth, and copper - used in their characteristic animal and bird sculptures. Elements of Hopewell culture appear to have been adopted by many other Indian groups.
South America was colonized by settlers from the north, possibly more than 13,000 years ago. By 10,000 BCE, hunter-gatherers had reached its southern tip. By 5000 BCE, communities were beginning to exploit local resources, such as corn, manioc, and potatoes. Successful agriculture led to growing populations and increasingly stratified societies. The distinctive temple mounds of Peru appeared by c.2500 BCE, and characteristic elements of South American religious iconography were disseminated from the Chavin culture in c.1200 BCE. By 300 CE, Peru was dominated by two major civilizations: the Nazca and the Moche.
The Earliest Settlements
The first South American settlers were hunter-gatherers, exploiting the big game which flourished following the last Ice Age. Spearheads and arrowheads indicate that this way of life had reached the far south of the continent by 10,000 BCE. In Chile, the site of Monte Verde reveals timber huts draped with animal hides by 11,000 BCE. Finds of medicinal plants, potato peelings, digging sticks, wooden bowls, and mortars, show an intimate knowledge of plant resources which supplemented a diet of small game and mastodon.
The first farmers of South America were located on the northern Pacific coast. Corn, the staple crop of the Americas, was cultivated in Ecuador c.6000 BCE; and the major high-altitude crop in the Andes, the potato, may have been grown by 4000 BCE. Llamas and alpaca, domesticated for their wool, were used as Andean pack animals. Manioc, which became a staple of tropical forest farmers, was cultivated in the Amazon Basin by 3000 BCE.
The Peoples of the Amazon Basin and Atlantic Coast
Rock shelters and flaked stone tools dating to c.10,000 BCE provide the earliest evidence of settlement east of the Andes. The transition from hunting and gathering to agriculture probably began c.3000 BCE. Large shell middens at the mouths of the Amazon and Orinoco rivers contain remains of pottery dating to c.5000 BCE, far earlier than the first pottery of Peru. When corn was introduced into the river flood plains in the first millennium BCE, populations expanded and hierarchical societies developed. Drainage earthworks in some areas suggest large populations were cooperating to farm the landscape.
The Early Cultures of Peru
The most influential culture of the Andes at this time was that of the Chavin, which flourished at and around the major religious center of Chavin de Huantar between 850 BCE and 200 BCE. The Chavin were distinguished by the sophistication of their architecture and sculptural style and by technological developments including the building of canals. As Chavin influence waned, many distinctive regional cultures developed in the Andean highlands. Coastal Peru, however, was dominated by two major civilizations, the Nazca in the south, and Moche in the north. As these cultures developed a strong identity, military rivalries intensified, paving the way for the appearance of other major states to come.
"The History of the Native Peoples of the America: Introduction-The First People in the New World" (Wikibooks) http://en.wikibooks.org/wiki/The_History_of_the_Native_Peoples_of_the_Americas/Introduction_-_The_First_People_in_the_New_World