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North America - Geography.

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North America - Geography. I INTRODUCTION North America, third largest of the seven continents, including Canada (the 2nd largest country in area in the world), the United States (3rd largest), and Mexico (14th largest). The continent also includes Greenland, the largest island, as well as the small French overseas department of Saint-Pierre and Miquelon and the British dependency of Bermuda (both made up of small islands in the Atlantic Ocean). With 528 million inhabitants (2008 estimate), North America is the 4th most populous continent; the United States ranks 3rd and Mexico 11th in population among the world's countries. Canada and the United States have technologically developed early modern economies, and Mexico, although less technologically developed than its neighbors, contains some of the world's greatest deposits of petroleum and natural gas. Together with Central America, the West Indies, and South America, North America makes up the Western Hemisphere of Earth. North America is sometimes defined to include Central America and the West Indies, which are treated separately in Encarta Encyclopedia. The name America is derived from that of Italian navigator Amerigo Vespucci, who may have visited the mainland of North America in 1497 and 1498. II THE NATURAL ENVIRONMENT North America is roughly wedge shaped, with its broadest expanse in the north. Most of its bulk is in the middle latitudes, with a considerable northern section in the Arctic and a narrow part around the tropic of Cancer. The continent sprawls east-west across some 176° of longitude, from longitude 12° west at Nordost Rundingen (Northeast Foreland) in northeastern Greenland to longitude 172° east at the western extremity of Attu Island, Alaska. Its north-south extent is some 69°, from latitude 83° north at Cape Morris Jesup in eastern Greenland to latitude 14° north in southern Mexico. North America is bordered on the north by the Arctic Ocean; on the east by the Atlantic Ocean; on the south by the Gulf of Mexico, Central America, and the Pacific Ocean; and on the west by the Pacific Ocean. The area of the continent is 23.7 million sq km (9.2 million sq mi). The outline of North America is exceedingly irregular; some extensive coastal reaches are relatively smooth, but by and large the coastline is broken and embayed, with many prominent offshore islands. The continent has three enormous coastal indentations: Hudson Bay in the northeast, the Gulf of Mexico in the southeast, and the Gulf of Alaska in the northwest. There are many small islands near the eastern and western coasts, but the most prominent islands are in the far north. A Geological History According to a widely accepted theory, almost all of North America is situated on the North American plate, an enormous platform considered one of about a dozen major units constituting the structural mosaic of the earth's crust. It is thought that North America was once joined to modern-day Europe and Africa and that it began to break away about 170 million years ago, in the Jurassic Period, with the process of continental drift accelerating about 95 million years ago, in the Cretaceous Period. As North America drifted west at a rate of 1.25 cm (0.5 in) per year, the plate underlying the Pacific Ocean is believed to have thrust under the North American plate, thereby causing widespread early folding, evident today in a series of high mountains along the western coast. As the Atlantic Ocean widened, it caused extensive faulting along the eastern coast, resulting in the creation of mountains and offshore islands. B Natural Regions North America can be divided into five major natural regions. The eastern half of Canada, as well as most of Greenland and sections of Minnesota, Wisconsin, Michigan, and New York in the United States, are part of the Canadian Shield (or Laurentian Plateau), which is a plateau region underlain by ancient crystalline rocks. The region has poor soil, and dense forests cover much of its southern part. A second region is made up of a coastal plain in most of the eastern United States and Mexico. In the United States the coastal plain is bordered on the west by a third region, comprising a relatively narrow cordillera of mountains and hills, notably the rounded Appalachian Mountains. A fourth region consists of the central portion of the continent, from southern Canada to southwestern Texas, which encompasses an extensive lowland that has experienced alternating periods of submergence beneath the sea and uplift, with the result that it is deeply covered with layers of sedimentary rock. It is not an uninterrupted flatland but includes much undulating and even hilly terrain, such as the Ozark Plateau. The western portion is made up of the Great Plains, which slope upward to the foot of the Rocky Mountains. The fifth, and westernmost, region of North America, taking in most of Mexico, is an active zone of mountain building; its recent geological history is dominated by crustal movements and volcanic activity. Adjacent to the Great Plains in the United States and Canada are the Rocky Mountains, which are geologically related to the Sierra Madre Oriental range of Mexico. To the west is an area of scattered basins and high plateaus, including the Interior Plateau of British Columbia in Canada, the Colorado Plateau and the Great Basin of the United States, and the vast central plateau of Mexico. Along the Pacific coast are a number of lofty mountain systems, extending from the Alaska Range to the Sierra Madre Occidental and Sierra Madre del Sur of Mexico. In between are ranges such as the Coast Mountains of British Columbia and the Cascade Range, the Coast Ranges, and the Sierra Nevada of the United States. Interspersed are some low-lying areas, notably the fertile Central Valley of California. The highest point in North America, Mount McKinley, or Denali (6,194 m/20,320 ft), is situated in the Alaska Range, and the lowest point, 86 m (282 ft) below sea level, is in Death Valley, California, a part of the Great Basin. C Drainage The Continental, or Great, Divide, which mainly runs along the crest of the Rocky Mountains, splits North America into two great drainage basins. To the east of the divide, water flows toward the Arctic Ocean, Hudson Bay, the Atlantic Ocean, and the Gulf of Mexico, and to the west, rivers flow toward the Pacific Ocean. Two prominent drainage systems--the Great Lakes-St. Lawrence River system and the Mississippi-Missouri river system--dominate the hydrography of eastern and central North America. The five Great Lakes (Superior, Michigan, Huron, Erie, and Ontario) drain northeast to the Atlantic Ocean via the relatively short St. Lawrence River. Most of the central part of the United States and a small part of southern Canada are drained south to the Gulf of Mexico by the Mississippi River and its tributaries, notably the Missouri River. A great many short, but often voluminous, rivers flow to the Atlantic and Gulf of Mexico along the well-watered eastern coasts of Canada, the United States, and Mexico. The northern interior of the continent is drained by the great Mackenzie River system of western Canada and by the numerous rivers that flow into Hudson Bay. To the west of the Continental Divide are relatively few major rivers (notably the Colorado, Columbia, Fraser, and Yukon) and many short, large-volume streams. The southern half of North America contains only a few large natural lakes, but Canada and the northern United States have a vast number of sizable lakes. Lake Superior, the world's biggest freshwater lake, and 10 of the next 25 largest natural lakes are found in this region. Lake Mead, on the Colorado River in the United States, is a large artificial lake, and Great Salt Lake, in Utah, is noted for its highly saline water. D Climate Although North America has considerable climatic variety, five principal climatic regions can be identified. The northern two-thirds of Canada and Alaska, as well as all of Greenland, have subarctic and arctic climates, in which long, dark, bitterly cold winters alternate with brief, mild summers. Most of the region, which receives relatively little precipitation, is covered with snow and ice during much of the year. A second climatic region is made up of the eastern two-thirds of the United States and southern Canada. It is characterized by a humid climate in which all four seasons are evident, and weather changes are frequent. The southern part of this region has a warmer average temperature. A third region includes the western interior of the United States and much of northern Mexico. It is mostly mountain and desert country, generally receiving small amounts of precipitation, but with significant local variations due to altitude and exposure. A fourth climatic region is made up of a narrow zone along the Pacific Ocean from southern Alaska to southern California. It has relatively mild but wet winters and almost rainless summers. Most of southern Mexico has a tropical climate, with year-round warmth and considerable precipitation, especially in summer. E Vegetation The natural vegetation of North America has been significantly modified by human activity, but its general nature is still apparent over much of the continent. The most notable forest is the taiga, or boreal forest, an enormous expanse of mostly coniferous trees (especially spruce, fir, hemlock, and larch) that covers most of southern and central Canada and extends into Alaska. In the eastern United States a mixed forest, dominated by deciduous trees in the north and by various species of yellow pine in the southeast, has mostly been cleared or cut over, but a considerable area has regrown since the 1940s. In the western portion of the continent, forests are primarily associated with mountain ranges, and coniferous trees are dominant. In California, the redwood and giant sequoia grow to enormous size. A great mixture of species characterizes the tropical forests of Mexico. The vegetation cover in the drier parts of the continent is made up mainly of grassland and shrubland. The central plains and prairies of the United States and southern Canada were originally grass covered, but much of the natural flora has been replaced by commercial crops. The dry lands of the western United States and northern Mexico are sparsely covered with a variety of shrubs and many kinds of cactus. Beyond the tree line in the far north is a region of tundra, containing a mixture of lowgrowing sedges, grasses, mosses, and lichens. F Animal Life The native wildlife of North America was once numerous and diverse, but the spread of human settlement has resulted in contracting habitats and diminishing numbers. In general, the fauna of North America is similar to that of the northern areas of Europe and Asia. Notable large mammals include several kinds of bear, the largest being the grizzly; bighorn sheep; bison, now only in protected herds; caribou; moose, called elk in Europe; musk-ox; and wapiti. Large carnivores include the puma and, in southernmost regions, the jaguar; the wolf and its smaller relative, the coyote; and, in the far north, the polar bear. One species of marsupial, the common opossum, is indigenous to the continent. A few of the many reptiles are poisonous, including the coral snake, pit vipers such as the rattlesnake and copperhead, and the Gila monster and beaded lizard of the southwestern United States and Mexico, the only poisonous lizards in the world. A great variety of finfish and shellfish live in the marine waters off North America, and many kinds of fish are found in its freshwater rivers and lakes. G Mineral Resources North America has large deposits of many important minerals. Petroleum and natural gas are found in great quantity in northern Alaska, western Canada, the southern and western conterminous United States, and eastern Mexico; huge beds of coal are in eastern and western Canada and the United States; and great iron-ore deposits are in eastern Canada, the northern United States, and central Mexico. Canada also has major deposits of copper, nickel, uranium, zinc, asbestos, and potash; the United States contains great amounts of copper, molybdenum, nickel, phosphate rock, and uranium; and Mexico has large reserves of barite, copper, fluorite, lead, zinc, manganese, and sulfur. All three countries have significant deposits of gold and silver. III THE PEOPLE North America was sparsely populated until relatively recent times. With the conspicuous exception of the inhabitants of the Mexican heartland (the plateaus and valleys around present-day Mexico City), the indigenous peoples of the continent were geographically scattered and culturally diverse. The settlement of the continent by Europeans began an almost total change in its human geography; Europeans decimated and displaced the indigenous peoples, and the living patterns of most were greatly altered. The contemporary population of North America is mostly European in background, but the continent's population also contains many other important groups. A Ethnography At least 35 percent of Canada's inhabitants trace their ancestry to the British Isles, and another 25 percent are of French background; the latter live mostly in Québec Province. The country also has significant numbers of people of German, Italian, Polish, Ukrainian, Chinese, Dutch, and Scandinavian descent. The population of the United States is more diverse than Canada's. In 1990, people of at least part British or part Irish background formed the largest group, with approximately 29 percent of the country's inhabitants. Blacks, who trace their ancestry to Africa, make up 12 percent of the population, Germans 23 percent, and people of Hispanic background 9 percent. The country also has large numbers of people of Italian, Polish, French, Russian, Dutch, and Scandinavian ancestry. Persons of Asian origin--primarily Japanese, Chinese, Filipinos, Asian Indians, Koreans, and Vietnamese--make up only 2.9 percent of the population of the United States, but since the 1970s the number of Asians increased significantly through immigration. Indigenous peoples, including Inuit and Eskimo, number 1.9 million in the United States and 800,000 in Canada. It is believed that the ancestors of the Native Americans migrated from northeastern Asia to North America via a prehistoric land bridge across the modern Bering Strait, off Alaska, that existed from about 25,000 to nearly 10,000 years ago. The forebears of the Inuit migrated from Asia by boat some 6,000 years ago. Some 30,000 Inuit live in Greenland. Some 60 percent of the people of Mexico are mestizos, persons of mixed Native American and European (mainly Spanish) descent. Approximately 30 percent of the population is of relatively pure Native American ancestry, and some 10 percent is of unmixed European descent. B Demography In 2008 the United States had 303,824,650 inhabitants; Mexico 109,955,400; Canada 33,679,263; and Greenland 56,326. Most of the population was concentrated in the eastern half of the United States and adjacent parts of Ontario and Québec, the U.S. Pacific coast, and the central plateau of Mexico. In the late 1990s more than 76 percent of the inhabitants of Canada, the United States, and Greenland were defined as urban, as were 74 percent of all Mexicans. The principal urban areas were on the U.S. Atlantic coast from Boston to Washington, D.C., around the shores of Lakes Erie and Ontario, at the southern end of Lake Michigan, in northern and southern California, and greater Mexico City. The largest cities included Mexico City, Guadalajara, and Monterrey, in Mexico; New York City, Los Angeles, Chicago, Houston, Philadelphia, and San Diego, in the United States; and Toronto, Montréal, Vancouver, Ottawa, and Edmonton, in Canada. Away from the metropolitan areas, most of North America had only a sparse to moderate population density. In Mexico the overall population density was 57.2 persons per sq km (148.1 per sq mi); in the United States, 33.2 per sq km (86 per sq mi); and in Canada, 3.7 per sq km (9.6 per sq mi). The great majority of Canadians lived in a relatively narrow band along the southern boundary. In both Canada and the United States the rate of population increase has declined since the 1950s. The Canadian population increased by about 1 percent per year from 1980 to 1990, when the annual growth rate for the United States was also 1 percent and for Greenland, 1.2 percent. Mexico, however, had one of the hemisphere's highest rates of population increase, 2.2 percent per year, and its birth rate (20 per 1,000 people in 2008) was about double that of the rest of the continent. The death rate was 5 per 1,000 people in Mexico, 8 in Canada, and 8 in the United States Intercontinental migration to North America was significant in the 1980s and 1990s, with large numbers of Asians and Europeans going to the United States and Canada. In addition, many people moved from South American and Caribbean countries to the United States. The largest population movements, however, occurred within North America itself, from Mexico to the United States and from the northeastern United States to southern and western parts of the country. C Languages English is the principal language for some 90 percent of the people of the United States and for about two-thirds of all Canadians. Spanish is spoken by the majority of Hispanic people in the United States, and French is the chief tongue for about one-quarter of the Canadian population. Many of the indigenous peoples and Inuit of the United States, Canada, and Greenland use their traditional languages. Spanish is the dominant language of Mexico, but several million Mexicans speak a Native American language. D Religion Christianity is the major religion of North America. The great majority of Mexicans are Roman Catholics, and some 45 percent of Canadians and 26 percent of U.S. inhabitants profess Roman Catholicism. Some 28 percent of Canada's people are Protestants and 8 percent are Anglicans. In the United States, Protestants make up 58 percent of the population. Canada and the United States also have substantial communities of Jews and Eastern Orthodox Christians. E Cultural Activity Cultural life in the United States and Canada is highly developed and diversified, with the mass media (radio, television, motion pictures, and newspapers) playing an important role. Almost all North American cities support theatrical organizations and art museums, and musical groups are widespread. Traditional cultural patterns are more evident in the rural areas of Mexico, but its cities have a variety of modern cultural institutions. IV PATTERNS OF ECONOMIC DEVELOPMENT The economic activities of North America are extraordinarily diverse. The United States and Canada have sophisticated modern economies. Modernization has been uneven in Mexico, with major developments in power, transportation, and manufacturing undercut by chronic inflation and a staggering burden of debt. A Agriculture Farming is relatively more important in Mexico than it is in the other North American countries and provides employment for 28 percent of the labor force (compared with some 3 percent in the United States and 4 percent in Canada). Subsistence farming is still important throughout Mexico, especially in the south; commercial agriculture is well developed in many areas, however, particularly in the central plateau and in the north. The leading commodities are corn, wheat, and beans, which are raised mostly for domestic consumption, and cotton, cattle, coffee, and sugar, which are produced largely for export. Agriculture in the United States and Canada is dominated by highly mechanized farms, which produce immense quantities of crops, livestock, and livestock products. The Great Plains of the central United States and the Canadian Prairie Provinces (Alberta, Manitoba, Saskatchewan) are major world producers of grain (particularly wheat, but also barley, oats, rye, and grain sorghum), oilseeds, and livestock (dairy and beef cattle and sheep). Perhaps the world's finest large farming area is the Corn Belt, that part of the U.S. Middle West from western Ohio to eastern Nebraska, which is the world's largest producer of corn, as well as a major supplier of other grains, soybeans, cattle, and hogs. Farming in California yields a huge amount of high-value irrigated crops, notably fruits and vegetables. Florida and Texas also are great producers of fruits and vegetables, and potatoes are grown in vast quantities in Idaho, Washington State, Oregon, Maine, North Dakota, and southeastern Canada. Other outstanding agricultural products include cotton, broiler chickens, dairy products, and sugarcane. B Forestry and Fishing Forestry is an important sector of the Canadian economy, especially in British Columbia, Ontario, and Québec Province. Notable forest-products industries also flourish in the western United States (particularly in Washington, Oregon, and California) and in the southeastern United States. Fishing is the leading economic activity in Greenland but is a relatively unimportant sector in Canada, the United States, and Mexico, even though the catch is large and some coastal areas are dependent on revenues from sales of finfish and shellfish. Besides the waters near Greenland, major fishing grounds are off the northern Pacific coast, off the northern Atlantic coast, and off the southern Atlantic and Gulf of Mexico coasts. In addition, large tuna fleets are based in southern California and western Mexico. C Mining The extraction of minerals is an increasingly important economic activity in the United States, Canada, and Mexico. The United States has been one of the world's leading petroleum producers for many years, Canada has been a major producer since the late 1940s, and Mexico became a world leader in oil production in the late 1970s. The United States ranks second among world natural-gas producers and is also a leader in mining coal, produced particularly in the vast Appalachian fields. Iron ore has long been a major product of both the United States and Canada, primarily from deposits around the western end of Lake Superior. More recently, much iron ore has been produced in the Québec Province-Labrador border area of eastern Canada. Among the other minerals that have been recovered in quantity in North America are copper, silver, lead, zinc, nickel, sulfur, asbestos, uranium, phosphate rock, and potash. D Manufacturing Manufacturing has long been a leading economic sector of the United States. The principal concentrations of factories have been located in the urban areas of a manufacturing belt extending roughly from Boston to Chicago. Since the 1950s, however, manufacturing has expanded considerably in other parts of the country, particularly in the big cities of California and in the southeastern states. Output is extremely diversified, with emphasis on primary and fabricated metals, processed food, machinery, electronic and aerospace equipment, motor vehicles, chemicals, textiles, clothing, paper, and printed materials. Manufacturing also is a principal economic activity in Canada. Factories are situated primarily in the cities of Ontario, Québec Province, British Columbia, and Alberta; Toronto and Montréal are the leading manufacturing centers. Canadian firms produce a wide variety of goods, especially processed food and beverages, transportation equipment, paper and other forest products, primary and fabricated metals, chemicals, and electrical and electronic equipment. Manufacturing has become an increasingly important part of the Mexican economy since the 1940s. Although not as technologically developed as in the United States and Canada, factories in Mexico produce a broad spectrum of goods, notably chemicals, clothing, processed food, motor vehicles and motor-vehicle parts, construction materials, and electrical and electronic equipment. Mexico City is by far the leading manufacturing center, but several other cities, including Monterrey and Guadalajara, have important concentrations of factories. E Energy North America consumes great quantities of energy. Canada depends much more on hydroelectricity than do the United States and Mexico, but it also makes heavy use of petroleum and natural gas. The enormous consumption of energy in the United States requires great imports of petroleum and natural gas to bolster the considerable domestic output of coal, petroleum, natural gas, and hydroelectric and nuclear power. Mexico's energy production expanded considerably in the 1970s and early 1980s, primed by the increased domestic recovery of petroleum and natural gas. F Transportation The transportation network of North America is extremely well developed in most parts of the conterminous United States and in southernmost Canada. A remarkable system of limited-access interstate highways was built in the United States beginning in the 1950s, and the country in addition has a wide-ranging network of other allweather roads. The rail network also is well established; it is critical for many types of freight transport but is a relatively unimportant passenger carrier. Air traffic grew considerably after 1945, and an expansive network of routes was created. Inland waterways, particularly the St. Lawrence Seaway-Great Lakes system and the Mississippi-Missouri river system, are important freight-transportation routes. Central and northern Canada and Alaska have only limited surface transportation facilities and depend heavily on air service. The interior transportation systems of Mexico are unevenly developed. All three countries have extensive modern facilities for handling oceangoing vessels. G Trade The United States is by far the leading trade partner for both Canada and Mexico, which in turn are significant, but not dominant, trade partners of the United States. The North American Free Trade Agreement (NAFTA), which took effect January 1, 1994, outlined the elimination of trade barriers between the three nations over the following 15 years. In 1997 NAFTA countries had a combined population of more than 395 million and a combined gross domestic product of $8.9 trillion. NAFTA forms one of the two largest free trade zones in the world. The organization is expected to add member nations from the region. Primary U.S. exports are machinery, motor vehicles, foodstuffs, chemicals, and aircraft. Canada ships mainly motor vehicles, machinery, metal and metal ore, forest products, chemicals, and foodstuffs, and the major exports of Mexico are crude petroleum, coffee, and metal ore. At the end of the 1980s the value of Canada's annual exports exceeded that of its imports, whereas the United States and Mexico regularly paid more for imports than their exports earned. The United States ranks among the world's leading trading countries in terms of the total value of imports and exports. V HISTORY According to archaeological evidence, human occupation of North America began during the late Pleistocene Epoch, when great sheets of ice covered much of the Northern Hemisphere. People are thought to have migrated to the continent from Asia over a land bridge across what is now the Bering Strait. Most anthropologist believe small bands of hunters and gathers crossed this land bridge at least 15,000 years ago; some scholars believe the earliest migrants arrived much earlier, perhaps 30,000 years ago or longer. From these beginnings human habitation is thought to have spread south and eastward. For more information about the peopling of the Americas, see First Americans. These earliest inhabitants were Stone Age people, who lived by hunting and gathering, using implements not unlike those known from Southeast Asia. They were later supplanted by other migrants with more advanced tools. These people are believed to be the earliest ancestors of the Native North Americans who developed complex cultures and inhabited the continent at the time when Europeans first arrived. (For a detailed discussion of Native American history and culture, See Native Americans of North America; Archaeology.) Greenland, geologically a part of North America, was the first part of the Western Hemisphere reached by Europeans. According to Icelandic sagas, it was first explored and settled by Erick the Red. The first European to see any part of the continental mainland was probably Bjarni Herjólfsson, an Icelandic trader, who sighted it about AD 986. Then Leif Eriksson, the son of Erik the Red, made a voyage to a land he called Vinland or Wineland, believed to have been somewhere between Labrador and New England. This account was partly substantiated by the discovery in 1963 of a Viking-type settlement site at L'Anse aux Meadows, in northern Newfoundland. The ruins were determined to be from about 1000. A Age of Exploration Consecutive European explorations in North America began with the voyage made in 1492 by Christopher Columbus in the service of Spain. His three ships sailed from Palos de la Frontera, Andalucía, on August 3, and on October 12 made landfall in the Bahamas. Although the exact landing site is disputed, most historians favor Samana Cay. Before returning to Europe, Columbus also landed on Cuba and Hispaniola. It was on Hispaniola that he established the first Spanish settlement in the Americas. He made three additional voyages between 1493 and 1502. In 1497 an Italian navigator in English service, John Cabot, landed on Cape Breton Island; in 1498 he also sailed along the Labrador, Newfoundland, and New England coasts, and possibly as far south as Delaware Bay. Portuguese navigator Gasper Corte-Real made a voyage in 1500 to the North American coast between Labrador and southeastern Newfoundland. In 1513 Juan Ponce de León, the Spanish governor of Puerto Rico, landed in Florida. Four years later Spanish soldier Francisco Fernández de Córdoba explored the Yucatán, and in 1518 Juan de Grijalva, a nephew of Spanish soldier Diego Velázquez, explored the eastern coast of Mexico, which he called New Spain. The following year Spanish conquistador Hernán Cortés invaded Mexico; he conquered it during the next two years. B Spanish Conquests Spanish conquest of the southern portion of the continent was substantially facilitated by the strife prevailing among the indigenous peoples of the region. Internal turbulence had been especially acute in the Aztec Empire, the rich domain that fell to Cortés in 1521. The Aztec Empire was the largest and most politically powerful in North America at that time. However, the empire was hated by many of the tribes under its sovereignty, and some of these tribes became willing allies of Cortés. Through this circumstance and superiority in weapons, Spanish victory was ensured. The Maya, another Mexican nation, living mainly on the Yucatán Peninsula, were also disunited and incapable of offering effective resistance to the Spanish. Although tens of thousands of indigenous peoples of Mexico and Central America were exterminated during the period of Spanish conquest and rule, the Aztec, Maya, and other peoples survived and multiplied. Their descendants constitute a majority of the present-day population of these areas. Cortés reached the region now known as Baja California in 1536. Among other important Spanish leaders of exploring expeditions during the first half of the 16th century were Pánfilo de Narváez and Álvar Núñez Cabeza de Vaca, who explored parts of Florida, the northern and eastern coasts of the Gulf of Mexico, and parts of northern Mexico between 1528 and 1536; Hernando de Soto, who reached and crossed the Mississippi River in 1541; and Francisco Vásquez de Coronado, who from 1540 to 1542 explored large areas in the southwestern part of the present-day United States. Saint Augustine, Florida, established in 1565 by Spanish explorer Pedro Menéndez de Avilés, is the oldest permanent European settlement in what is now the United States. By 1600 the Spanish had subjugated the indigenous peoples of the larger West Indian islands, of the Florida Peninsula, and of southern Mexico (New Spain). For administrative purposes the colonies founded by the Spanish in these areas were grouped in the Viceroyalty of New Spain. After consolidating their control of New Spain, the Spanish authorities gradually pushed northward, completing the conquest of Mexico and taking over large areas in the south of what is now the United States. The colonial policy of Spain in North America was identical in all important respects with its South American colonial policy--that is, economic exploitation. Regarding the colonies merely as a source of wealth, the Spanish rulers imposed confiscation taxation and maintained a monopoly of colonial trade. The Spanish government even forbade commercial trading among its American colonies. This oppressive economic policy and political tyranny created discontent that finally flared into open rebellion. C French and English Colonization While Spain was consolidating its position in southern North America, France and England explored and settled the continent from present-day Canada southward. England and Spain had been generally allied in international politics during the early part of the 16th century, and as a result the English did not then attempt to compete with Spain in North America. France, the chief rival of Spain for hegemony on the European continent, entered the race for colonial empire somewhat belatedly, but its territorial acquisitions in the New World were nonetheless important. In 1524 Florentine navigator Giovanni da Verrazzano, sailing in French service, followed the North American coast from Cape Fear northward to a point usually identified as Cape Breton. In the course of this voyage he explored what are now called Narragansett and New York bays. French explorer Jacques Cartier made three voyages between 1534 and 1542 in an area including the Gulf of St. Lawrence, the St. Lawrence River, and the settlement of indigenous people that later became the site of Montréal. France claimed most of the northern part of the continent on the basis of these explorations. Because of domestic turmoil resulting from the Protestant Reformation, the French were forced to suspend colonial activity for more than half a century. Beginning in 1599, they established fur-trading posts along the St. Lawrence River. Numerous French Jesuit priests came thereafter to the St. Lawrence region, seeking to convert the Native Americans to the Roman Catholic faith, and various French explorers found and claimed for France new and widely separate sections of the continent. Among the most notable of these explorers were Samuel de Champlain, who founded Québec in 1608 and explored what is now northern New York; Jesuit missionary Claude Jean Allouez, who opened up new territory around Lake Superior; and Jesuit missionary Jacques Marquette and explorer Louis Joliet, who in 1673 together explored the upper Mississippi River as far south as present-day Arkansas. In 1682 one of the most noted French pioneers in North America, RenéRobert Cavelier, sieur de La Salle, and his associate, Italian explorer Henri de Tonty, navigated the Mississippi from its junction with the Ohio River to the Gulf of Mexico, claiming all the land drained by the river for Louis XIV, king of France, and naming it Louisiana. The English crown laid claim to the North American continent on the strength of the Cabot voyage of 1497 to 1498, but for nearly a century made no attempts at colonization. The earliest colony in North America was established in 1583 near the present city of St. John's, Newfoundland and Labrador, by English navigator and soldier Sir Humphrey Gilbert, but the settlers returned to England the same year. Twice, in 1585 and in 1587, Sir Walter Raleigh attempted to establish a colony on Roanoke Island, in present-day North Carolina, but when English explorers called at Roanoke in 1590, they found no trace of the colonists (see Croatan). The first permanent British colony on the continent was Jamestown, established in Virginia in 1607. Plymouth Colony was founded in 1620 on the shores of Cape Cod Bay, and Massachusetts Bay Colony was established between 1628 and 1630 on the shores of Massachusetts Bay. After 1630 the English systematically colonized the entire Atlantic seaboard between French Acadia and Spanish Florida. In 1664 they annexed the Dutch colony of New Netherland, settled in 1624, which they renamed New York, and the settlements on the Delaware River that the Dutch had seized from Swedish colonists in 1655. The English colonies grew rapidly in population and wealth. For details, see United States (History). At the beginning of the last decade of the 17th century, most of the North American continent from Canada to the Gulf of Mexico was occupied by the French and English colonial empires. The French colonies were widely scattered. The principal settlements were grouped in Canada and near the mouth of the Mississippi River, and a line of trading and military posts along the Ohio and Mississippi rivers connected the two regions. The English colonial holdings consisted of 12 colonies extending along the Atlantic seaboard. A 13th, Georgia, was chartered in 1733. D War and Revolution As a consequence of efforts to expand westward beyond the Alleghenies, the English eventually came into conflict with the French in the Ohio Valley. In 1689 the two powers began a worldwide struggle for military and colonial supremacy. In North America the conflict was fought in four successive phases: King William's War, which lasted from 1689 to 1697; Queen Anne's War, from 1702 to 1713; King George's War, from 1744 to 1748; and the French and Indian War, from 1754 to 1763. Reverses suffered in the French and Indian War and in its European extension, the Seven Years' War (1756-1763), forced the French to capitulate. By the Treaty of Paris of 1763, France was forced to yield to Great Britain all its holdings in Canada and also all of Louisiana east of the Mississippi. France had previously ceded to Spain, its ally, New Orleans and all French territory west of the Mississippi. The outstanding event of the two decades from 1763 to 1783 on the continent was the economic, political, and military conflict between Great Britain and its 13 colonies along the Atlantic seaboard south of Canada. Generally called the American Revolution (1775-1783), this conflict ended in the establishment of the United States of America. The success of the 13 colonies in freeing themselves from the rule of their parent country soon had repercussions among the Spanish colonies in the Americas. Inspired by their victory and also by the outcome of the French Revolution (1789-1799), and taking advantage of the involvement of Spain in the Napoleonic Wars (1799-1815), in 1810 the Spanish colonies in the Americas began a struggle for independence. Mexico revolted against Spain in that year but did not actually become free until 1821. During the late 19th and early 20th centuries, Canada also succeeded in obtaining from Britain a full degree of self-government. See Canada: History. E United States Expansion Other developments marked the history of North America in the 19th and 20th centuries. The first involved the increasing importance of the United States, marked by the nation's unparalleled growth in population and wealth, and its territorial growth; its resolution of many internal economic and political problems, particularly those of slavery and national unity; and its emergence toward the end of the 19th century as a world power. The U.S. territorial expansion was marked by warfare against Native Americans who resisted encroachment on their domains. Except in scattered areas, particularly in the southern Appalachians, the Native Americans living east of the Mississippi River had been eliminated as an effective force by the final decade of the 18th century. Some of the tribes had withdrawn westward, but the great majority had been substantially diminished or completely destroyed. To a large degree, the fate of the indigenous peoples of eastern North America was a result of the wars and political rivalries among the colonizing powers, particularly the French and English, who involved the tribes in their struggles for territorial supremacy. Many thousands of indigenous peoples, however, perished in attempts to maintain their ancestral lands and cultural identity in spite of the usurpers. Between 1832 and 1877, the Native Americans of the Great Plains, the Southwest, and the Rocky Mountains contested almost every major European move westward. Ultimately, however, it was not primarily armed battles that subjugated the Native Americans, but rather devastating disease, forced assimilation, and expropriation of their land by means of treaties and legislation. Both in the United States and Canada the majority of Native Americans continue to live on reservations. In many of these areas, which represent a poorly integrated fusion of Native American civilization with that of whites, the economic plight of the indigenous peoples is serious. In addition to acquisitions of contiguous territory in the 19th and 20th centuries, the United States obtained other regions in North America: Alaska, purchased from Russia in 1867 for $7 million; Puerto Rico, ceded by Spain in 1898 after the Spanish-American War; the Panama Canal Zone, acquired in 1903 but ceded to Panama in 1979; and the Virgin Islands of the United States, purchased from Denmark in 1917 for $25 million. F Hemispheric Developments A second important development in the history of the continent in the 19th and especially in the 20th century was the participation of the North American nations in the movement manifest throughout the Western Hemisphere for economic cooperation, for the attainment of peace and mutual understanding, and for solidarity against potential aggressors. In this movement the United States played a leading part, starting in 1823 with the Monroe Doctrine--the proclamation of President James Monroe that the United States would not permit European control of territories in the Americas beyond that existing at the time. The only serious intracontinental conflict was the so-called Mexican War (1846-1848) between the United States and Mexico. During the 20th century a tendency toward mutual friendship developed among the nations of the Western Hemisphere, given form in 1910 with the establishment of the Pan-American Union. Almost all the nations of the Western Hemisphere either declared war on or broke diplomatic relations with the Central Powers in World War I (1914-1918) and with the Axis Powers in World War II (1939-1945). One of the most important demonstrations of hemispheric solidarity was the Inter-American Defense Conference of 1947, which promulgated the Inter-American Treaty of Reciprocal Assistance--the Rio Treaty--which was signed by the United States, Mexico, and 17 Central and South American nations. The treaty provides for settlement of disagreements between nations of the Western Hemisphere, as well as for joint defense against aggression on the region extending from the Bering Sea to the South Pole. In 1948 the Organization of American States (OAS) was formed to implement the Rio Treaty and to serve as a collective security system. Hemispheric cooperation was temporarily furthered by the Alliance for Progress, which was established in 1961. The alliance, which was accepted by the United States and 19 Latin American nations at Punta del Este, Uruguay, consisted of a ten-year development plan to raise the economic and social levels of the area and to strengthen its democratic institutions. After the original ten-year period, however, the alliance showed mixed results, and it gradually ceased to function. The existence after 1959 of a Communist government in Cuba tended to complicate hemispheric activities. In 1962, at Punta del Este, the OAS voted to exclude Cuba from participation in the Inter-American system because of that nation's alignment with the countries of the Communist bloc. The relations between the United States and Canada have been particularly friendly and cooperative since the War of 1812. No military installations aimed at defense against each other have existed since that time on the entire border between the two nations. The United States and Canada collaborated closely in the fight against the Axis Powers during World War II. In the postwar period, usually referred to as the era of the Cold War, the Canadian and American governments initiated plans for joint defense against possible aggression from the Soviet Union across the Arctic regions. Mexico's serious internal strife from 1910 to 1920 and its nationalization of U.S. oil companies in 1938 plagued relations between the two nations during the first half of the 20th century. More recently, however, their relationship has been more friendly, as evidenced by the signing of the North American Free Trade Agreement (NAFTA), which encouraged trade among the United States, Mexico, and Canada. Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.

« D Climate Although North America has considerable climatic variety, five principal climatic regions can be identified.

The northern two-thirds of Canada and Alaska, as well as all ofGreenland, have subarctic and arctic climates, in which long, dark, bitterly cold winters alternate with brief, mild summers.

Most of the region, which receives relativelylittle precipitation, is covered with snow and ice during much of the year.

A second climatic region is made up of the eastern two-thirds of the United States andsouthern Canada.

It is characterized by a humid climate in which all four seasons are evident, and weather changes are frequent.

The southern part of this region has awarmer average temperature.

A third region includes the western interior of the United States and much of northern Mexico.

It is mostly mountain and desert country,generally receiving small amounts of precipitation, but with significant local variations due to altitude and exposure.

A fourth climatic region is made up of a narrow zonealong the Pacific Ocean from southern Alaska to southern California.

It has relatively mild but wet winters and almost rainless summers.

Most of southern Mexico has atropical climate, with year-round warmth and considerable precipitation, especially in summer. E Vegetation The natural vegetation of North America has been significantly modified by human activity, but its general nature is still apparent over much of the continent.

The mostnotable forest is the taiga, or boreal forest, an enormous expanse of mostly coniferous trees (especially spruce, fir, hemlock, and larch) that covers most of southernand central Canada and extends into Alaska.

In the eastern United States a mixed forest, dominated by deciduous trees in the north and by various species of yellowpine in the southeast, has mostly been cleared or cut over, but a considerable area has regrown since the 1940s.

In the western portion of the continent, forests areprimarily associated with mountain ranges, and coniferous trees are dominant.

In California, the redwood and giant sequoia grow to enormous size.

A great mixture ofspecies characterizes the tropical forests of Mexico. The vegetation cover in the drier parts of the continent is made up mainly of grassland and shrubland.

The central plains and prairies of the United States and southernCanada were originally grass covered, but much of the natural flora has been replaced by commercial crops.

The dry lands of the western United States and northernMexico are sparsely covered with a variety of shrubs and many kinds of cactus.

Beyond the tree line in the far north is a region of tundra, containing a mixture of low-growing sedges, grasses, mosses, and lichens. F Animal Life The native wildlife of North America was once numerous and diverse, but the spread of human settlement has resulted in contracting habitats and diminishing numbers.In general, the fauna of North America is similar to that of the northern areas of Europe and Asia.

Notable large mammals include several kinds of bear, the largestbeing the grizzly; bighorn sheep; bison, now only in protected herds; caribou; moose, called elk in Europe; musk-ox; and wapiti.

Large carnivores include the pumaand, in southernmost regions, the jaguar; the wolf and its smaller relative, the coyote; and, in the far north, the polar bear.

One species of marsupial, the commonopossum, is indigenous to the continent.

A few of the many reptiles are poisonous, including the coral snake, pit vipers such as the rattlesnake and copperhead, and theGila monster and beaded lizard of the southwestern United States and Mexico, the only poisonous lizards in the world.

A great variety of finfish and shellfish live in themarine waters off North America, and many kinds of fish are found in its freshwater rivers and lakes. G Mineral Resources North America has large deposits of many important minerals.

Petroleum and natural gas are found in great quantity in northern Alaska, western Canada, the southernand western conterminous United States, and eastern Mexico; huge beds of coal are in eastern and western Canada and the United States; and great iron-ore depositsare in eastern Canada, the northern United States, and central Mexico.

Canada also has major deposits of copper, nickel, uranium, zinc, asbestos, and potash; theUnited States contains great amounts of copper, molybdenum, nickel, phosphate rock, and uranium; and Mexico has large reserves of barite, copper, fluorite, lead,zinc, manganese, and sulfur.

All three countries have significant deposits of gold and silver. III THE PEOPLE North America was sparsely populated until relatively recent times.

With the conspicuous exception of the inhabitants of the Mexican heartland (the plateaus and valleysaround present-day Mexico City), the indigenous peoples of the continent were geographically scattered and culturally diverse.

The settlement of the continent byEuropeans began an almost total change in its human geography; Europeans decimated and displaced the indigenous peoples, and the living patterns of most weregreatly altered.

The contemporary population of North America is mostly European in background, but the continent's population also contains many other importantgroups. A Ethnography At least 35 percent of Canada's inhabitants trace their ancestry to the British Isles, and another 25 percent are of French background; the latter live mostly in QuébecProvince.

The country also has significant numbers of people of German, Italian, Polish, Ukrainian, Chinese, Dutch, and Scandinavian descent.

The population of theUnited States is more diverse than Canada's.

In 1990, people of at least part British or part Irish background formed the largest group, with approximately 29 percentof the country's inhabitants.

Blacks, who trace their ancestry to Africa, make up 12 percent of the population, Germans 23 percent, and people of Hispanic background9 percent.

The country also has large numbers of people of Italian, Polish, French, Russian, Dutch, and Scandinavian ancestry.

Persons of Asian origin—primarilyJapanese, Chinese, Filipinos, Asian Indians, Koreans, and Vietnamese—make up only 2.9 percent of the population of the United States, but since the 1970s the numberof Asians increased significantly through immigration. Indigenous peoples, including Inuit and Eskimo, number 1.9 million in the United States and 800,000 in Canada.

It is believed that the ancestors of the NativeAmericans migrated from northeastern Asia to North America via a prehistoric land bridge across the modern Bering Strait, off Alaska, that existed from about 25,000to nearly 10,000 years ago.

The forebears of the Inuit migrated from Asia by boat some 6,000 years ago.

Some 30,000 Inuit live in Greenland. Some 60 percent of the people of Mexico are mestizos, persons of mixed Native American and European (mainly Spanish) descent.

Approximately 30 percent of thepopulation is of relatively pure Native American ancestry, and some 10 percent is of unmixed European descent. B Demography In 2008 the United States had 303,824,650 inhabitants; Mexico 109,955,400; Canada 33,679,263; and Greenland 56,326.

Most of the population was concentrated inthe eastern half of the United States and adjacent parts of Ontario and Québec, the U.S.

Pacific coast, and the central plateau of Mexico.

In the late 1990s more than76 percent of the inhabitants of Canada, the United States, and Greenland were defined as urban, as were 74 percent of all Mexicans.

The principal urban areas wereon the U.S.

Atlantic coast from Boston to Washington, D.C., around the shores of Lakes Erie and Ontario, at the southern end of Lake Michigan, in northern and. »

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