North America covers an area of about 24,709,000 square kilometers (9,540,000 square miles), about 4.8% of the planet's surface or about 16.5% of its land area. As of July 2008, its population was estimated at nearly 529 million people across 23 independent states, representing about 7.5% of the human population. North America is the third-largest continent in area, following Asia and Africa, and the fourth in population after Asia, Africa, and Europe.[citation needed]
The first people to live in North America were Paleoindians who began to arrive during the last glacial period by crossing the Bering land bridge. They differentiated into a number of diverse cultures and communities across the continent. The largest and most advanced Pre-Columbian civilizations in North America were the Aztecs in what is now Mexico and the Mayans in Central America. European colonists began to arrive starting in the 16th and 17th centuries, wiping out large numbers of the native populations and beginning an era of European dominance.
Etymology
Map of North America, from the 16th century
The Americas are usually accepted as having been named after the Italian explorer Amerigo Vespucci by the German cartographers Martin Waldseemüller and Matthias Ringmann.[3] Vespucci, who explored South America between 1497 and 1502, was the first European to suggest that the Americas were not the East Indies, but a different landmass previously unknown by Europeans. In 1507, Waldseemüller produced a world map, in which he placed the word "America" on the continent of South America, in the middle of what is today Brazil. He explained the rationale for the name in the accompanying book Cosmographiae Introductio,
ab Americo inventore ... quasi Americi terram sive Americam (from Americus the discoverer ... as if it were the land of Americus, thus America).[4]
For Waldseemüller, no one should object to the naming of the land after its discoverer. He used the Latinized version of Vespucci's name (Americus Vespucius), but in its feminine form "America", following the examples of "Europa" and "Asia".
Later, when other mapmakers added North America, they extended the original name to it as well: in 1538, Gerard Mercator used the name America to all of the Western Hemisphere on his world map.[5]
Some argue that the convention is to use the surname for naming discoveries except in the case of royalty and so a derivation from "Amerigo Vespucci" could be problematic.[6] Ricardo Palma (1949) proposed a derivation from the "Amerrique" mountains of Central America—Vespucci was the first to discover South America and the Amerrique mountains of Central America, which connected his discoveries to those of Christopher Columbus.
Alfred E. Hudd proposed a theory in 1908 that the continents are named after a Welsh merchant named Richard Amerike from Bristol, who is believed to have financed John Cabot's voyage of discovery from England to Newfoundland in 1497. A minutely explored belief that has been advanced is that America was named for a Spanish sailor bearing the ancient Visigothic name of 'Amairick'. Another is that the name is rooted in a Native American language.[5]
History
Main article: History of North America
Geologic history
Laurentia is an ancient craton which forms the geologic core of North America; it formed between 1.5 to 1.0 billion years ago during the Proterozoic eon.[7] The Canadian Shield is the largest exposure of this craton. From the Late Paleozoic to Early Mesozoic eras, North America was joined with the other modern-day continents as part of the supercontinent Pangaea, with Eurasia to its east. One of the results of the formation of Pangaea was the Appalachian Mountains, which formed some 480 million years ago, making it among the oldest mountain ranges in the world. When Pangaea began to rift around 200 million years ago, North America became part of Laurasia, before it separated from Eurasia as its own continent during the mid-Cretaceous period.[8] The Rockies and other western mountain ranges began forming around this time from a period of mountain building called the Laramide orogeny, between 80 and 55 million years ago. The formation of the Isthmus of Panama connected the continent to South America about three million years ago, and the Great Lakes (as well as many other northern freshwater lakes and rivers) were carved by receding glaciers about 10,000 years ago.
North America is the source of much of what humanity knows about geologic time periods.[9] The geographic area that would later become the United States has been the source of more varieties of dinosaurs than any other modern country.[9] According to paleontologist Peter Dodson, this is primarily due to stratigraphy, climate and geography, human resources, and history.[9] Much of the Mesozoic Era is represented by exposed outcrops in the many arid regions of the continent.[9] The most significant Late Jurassic dinosaur-bearing fossil deposit in North America is the Morrison Formation of the western United States.[10]
Pre-Columbian
The ruins of Chichén Itzá, Mexico.
Anthropologists have a number of models explaining the origins of the early human population of North America. The indigenous peoples of North America have many creation myths by which they assert that they have been present on the land since its creation. The consensus is that indigenous North Americans first arrived from Asia during the last Ice Age, most likely through the Bering Land Bridge and possibly by primitive boats also.
Before contact with Europeans, the natives of North America were divided into many different polities, from small bands of a few families to large empires. They lived in several "culture areas", which roughly correspond to geographic and biological zones and give a good indication of the main lifeway or occupation of the people who lived there (e.g. the bison hunters of the Great Plains, or the farmers of Mesoamerica). Native groups can also be classified by their language family (e.g. Athapascan or Uto-Aztecan). Peoples with similar languages did not always share the same material culture, nor were they always allies. Anthropologists think that the Inuit people of the high Arctic came to North America much later than other native groups, as evidenced by the disappearance of Dorset culture artifacts from the archaeological record, and their replacement by the Thule people. It is possible that North America had several peoples among its early settlers.[11] The best known evidence that supports this theory is Kennewick Man.[12]
During the thousands of years of native habitation on the continent, cultures changed and shifted. One of the oldest cultures yet found is the Clovis culture of modern New Mexico. Later cultures include the Mississippian culture and related Mound building cultures, found in the Mississippi river valley and the Pueblo culture of what is now the Four Corners. The more southern cultural groups of North America were responsible for the domestication of many common crops now used around the world, such as tomatoes and squash. Perhaps most importantly they domesticated one of the world's major staples, maize (corn).
As a result of the development of agriculture in the south, many important cultural advances were made there. For example, the Maya civilization developed a writing system, built huge pyramids and temples, had a complex calendar, and developed the concept of zero around 400 CE, a few hundred years after the Mesopotamians.[13] The Mayan culture was still present in southern Mexico and Guatemala when the Spanish explorers arrived, but political dominance in the area had shifted to the Aztec Empire whose capital city Tenochtitlan was located further north in the Valley of Mexico. The Aztecs were conquered in 1521 by Hernán Cortés.[14]
Benjamin West's The Death of General Wolfe (1771) depicting the Battle of the Plains of Abraham.
Post-Columbian
During the Age of Discovery, Europeans began exploring and staking claims in various parts of North America. Upon their arrival in the "New World", the Native American population declined substantially, primarily due to the introduction of European diseases to which the Native Americans lacked immunity,[15] as well as violent conflicts. Native peoples found their culture changed drastically. As such, their affiliation with political and cultural groups changed as well, several linguistic groups went extinct, and others changed quite quickly. The names and cultures that Europeans recorded for the natives were not necessarily the same as the ones they had used a few generations before, or the ones in use today.
Britain, Spain, and France fought over and established extensive territories in North America. In the late 18th century and beginning of the 19th, several independence movements started across the continent, which would create its modern countries. The 13 British colonies on the North Atlantic coast declared independence in 1776, becoming the United States of America. Canada was formed from the unification of northern territories controlled by Britain and France. New Spain, a territory that stretched from modern-day southern U.S. to Central America, declared independence in 1810 becoming the First Mexican Empire. In 1823 the former Captaincy General of Guatemala, then part of the Mexican Empire, became the first independent state in Central America, officially changing its name to the United Provinces of Central America.
Geography and extent
Further information: Geography of North America
Satellite imagery of North America.
North America occupies the northern portion of the landmass generally referred to as the New World, the Western Hemisphere, the Americas, or simply America (which, less commonly, is considered by some as a single continent[16][17][18] with North America a subcontinent).[19] North America's only land connection to South America is at the Isthmus of Panama. The continent is delimited on the southeast by most geographers at the Darién watershed along the Colombia-Panama border, placing all of Panama within North America.[20][21][22] Alternatively, less common views would end North America at the man-made Panama Canal[citation needed], and some geologists physiographically locate its southern limit at the Isthmus of Tehuantepec, Mexico, with Central America extending southeastward to South America from this point.[23] The Caribbean islands, or West Indies, are considered part of North America.[2]
Before the Central American isthmus was raised, the region had been underwater. The islands of the West Indies delineate a submerged former land bridge which had connected North America and South America via what are now Florida and Venezuela. The continental coastline is long and irregular. The Gulf of Mexico is the largest body of water indenting the continent, followed by Hudson Bay. Others include the Gulf of Saint Lawrence and the Gulf of California.
There are numerous islands off the continent’s coasts, principally, the Arctic Archipelago, the Bahamas, Turks & Caicos, the Greater and Lesser Antilles, the Aleutian Islands (some of which are in the Eastern Hemisphere proper), the Alexander Archipelago, the many thousand islands of the British Columbia Coast, and Newfoundland. Greenland, a self-governing Danish island, and the world's largest, is on the same tectonic plate (the North American Plate) and is part of North America geographically. In a geologic sense, Bermuda is not part of the Americas, but an oceanic island which was formed on the fissure of the Mid-Atlantic Ridge over 100 million years ago. The nearest landmass to it is Cape Hatteras, North Carolina. However, Bermuda is often thought of as part of North America, especially given its historical, political and cultural ties to Virginia and other parts of the continent.
Moraine Lake in Banff National Park
The vast majority of North America is on the North American Plate. Parts of western Mexico, including Baja California, and of California, including the cities of San Diego, Los Angeles and part of San Francisco, lie on the eastern edge of the Pacific Plate, with the two plates meeting along the San Andreas fault. The southernmost portion of the continent and much of the West Indies lie on the Caribbean Plate, whereas the Juan de Fuca and Cocos plates border the North American Plate on its western frontier.
The continent can be divided into four great regions (each of which contains many subregions): the Great Plains stretching from the Gulf of Mexico to the Canadian Arctic; the geologically young, mountainous west, including the Rocky Mountains, the Great Basin, California and Alaska; the raised but relatively flat plateau of the Canadian Shield in the northeast; and the varied eastern region, which includes the Appalachian Mountains, the coastal plain along the Atlantic seaboard, and the Florida peninsula. Mexico, with its long plateaus and cordilleras, falls largely in the western region, although the eastern coastal plain does extend south along the Gulf.
The western mountains are split in the middle into the main range of the Rockies and the coast ranges in California, Oregon, Washington, and British Columbia, with the Great Basin—a lower area containing smaller ranges and low-lying deserts—in between. The highest peak is Denali in Alaska.
The United States Geographical Survey states that the geographic center of North America is "6 miles west of Balta, Pierce County, North Dakota" at approximately 48°10′N 100°10′W, approximately 15 miles (24 km) from Rugby, North Dakota. The USGS further states that “No marked or monumented point has been established by any government agency as the geographic center of either the 50 States, the conterminous United States, or the North American continent.” Nonetheless, there is a 15-foot (4.5 m) field stone obelisk in Rugby claiming to mark the center. The North American continental pole of inaccessibility is located 1,650 km (1,030 mi) from the nearest coastline, between Allen and Kyle, South Dakota at 43.36°N 101.97°W.
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