Officially United Mexican States, republic (1995 est. pop. 93,986,000), 753,665 sq mi (1,952,500 sq km), S North America. It borders on the United States in the north, on the Gulf of Mexico (including its arm, the Bay of Campeche) and the Caribbean Sea in the east, on Belize and Guatemala in the southeast, and on the Pacific Ocean in the south and west. Mexico is divided into 31 states and the Federal District, which includes most of the country's capital and largest city, Mexico City.
Most of Mexico is highland or mountainous and less than 15% of the land is arable; about 25% of the country is forested. Most of the Yucatán peninsula and the Isthmus of Tehuantepec in the southeast is lowland, and there are low-lying strips of land along the Gulf of Mexico, the Pacific Ocean, and the Gulf of California
In the south the deserts yield to the broad, shallow lakes of a region, comprising the Valley of Mexico, known as the Anáhuac and famous for its rich cultural heritage. South of the Anáhuac, which includes Mexico City, is a chain of extinct volcanoes, including Citlaltépetl , or Orizaba (18,700 ft/5,700 m, the highest point in Mexico), Popocatépetl , and Iztaccihuatl . To the south are jumbled masses of mountains and the Sierra Madre del Sur.
The great majority of the population are of mixed Spanish and indigenous descent and speak Spanish, the official language, as their first language. Various Mayan dialects are also spoken. Since 1920 the population of Mexico has had a very high rate of growth, almost entirely the result of natural increase; from 1940 to 1990 the population grew from 19.6 million to 81.1 million.
Geography and climate
Situated in southern North America at about 23° N and 102° W, Mexico comprises much of Middle America. Physiographically, the lands east of the Isthmus of Tehuantepec including the Yucatán Peninsula (which together comprise around 12% of the country's area) lie within Central America; geologically, the Trans-Mexican Volcanic Belt delimits the region on the north. Geopolitically, however, Mexico is commonly not considered a Central American country
Mexico's total area is 1,972,550 km², making it the world's 14th largest country by total area, and includes approximately 6,000 km² of islands in the Pacific Ocean (including the remote Guadalupe Island and the Islas Revillagigedo), Gulf of Mexico, Caribbean Sea, and Gulf of California. On its north, Mexico shares a 3,141 km border with the United States. The meandering Río Bravo del Norte (known as the Rio Grande in the United States) defines the border from Ciudad Juárez east to the Gulf of Mexico. A series of natural and artificial markers delineate the United States-Mexican border west from Ciudad Juárez to the Pacific Ocean. On its south, Mexico shares an 871 km border with Guatemala and a 251 km border with Belize.
Mexico is crossed from north to south by two mountain ranges known as Sierra Madre Oriental and Sierra Madre Occidental, which are the extension of the Rocky Mountains from northern North America. From east to west at the center, the country is crossed by the Trans-Mexican Volcanic Belt also known as the Sierra Nevada. A fourth mountain range, the Sierra Madre del Sur, runs from Michoacán to Oaxaca. As such, the majority of the Mexican central and northern territories are located at high altitudes, and the highest elevations are found at the Trans-Mexican Volcanic Belt: Pico de Orizaba (5,700 m), Popocatépetl (5,462 m) and Iztaccíhuatl (5,286 m) and the Nevado de Toluca (4,577 m).
Three major urban agglomerations are located in the valleys between these four elevations: Toluca, Greater Mexico City and Puebla.
The Tropic of Cancer effectively divides the country into temperate and tropical zones. Land north of the twenty-fourth parallel experiences cooler temperatures during the winter months. South of the twenty-fourth parallel, temperatures are fairly constant year round and vary solely as a function of elevation.
Areas south of the twenty-fourth parallel with elevations up to 1,000 meters (the southern parts of both coastal plains as well as the Yucatán Peninsula), have a yearly median temperature between 24 and 28 °C. Temperatures here remain high throughout the year, with only a 5 °C difference between winter and summer median temperatures. Although low-lying areas north of the twentieth-fourth parallel are hot and humid during the summer, they generally have lower yearly temperature averages (from 20 to 24 °C) because of more moderate conditions during the winter.
Many large cities in Mexico are located in the Valley of Mexico or in adjacent valleys with altitudes generally above 2,000 m, this gives them a year-round temperate climate with yearly temperature averages (from 16 to 18 °C) and cool nighttime temperatures throughout the year. Many parts of Mexico, particularly the north have a dry climate with sporadic rainfall while parts of the tropical lowlands in the south average more than 200 cm of annual precipitation.
Mexico is one of the 17 megadiverse countries of the world. With over 200,000 different species, Mexico is home of 10–12% of the world's biodiversity. Mexico ranks first in biodiversity in reptiles with 707 known species, second in mammals with 438 species, fourth in amphibians with 290 species, and fourth in flora, with 26,000 different species. Mexico is also considered the second country in the world in ecosystems and fourth in overall species.
Approximately 2,500 species are protected by Mexican legislations. The Mexican government created the National System of Information about Biodiversity, in order to study and promote the sustainable use of ecosystems.
In Mexico, 170,000 square kilometres are considered "Protected Natural Areas." These include 34 reserve biospheres (unaltered ecosystems), 64 national parks, 4 natural monuments (protected in perpetuity for their aesthetic, scientific or historical value), 26 areas of protected flora and fauna, 4 areas for natural resource protection (conservation of soil, hydrological basins and forests) and 17 sanctuaries (zones rich in diverse species).
*Columbia Encyclopedia, Sixth Edition, Copyright (c) 2003.