Arizona in the context of Lake Powell

Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird (Promerops cafer) is found exclusively in southwestern South Africa and is therefore said to be endemic to that particular part of the world. An endemic species can also be referred to as an endemism or, in scientific literature, as an endemite.

Endemism is an important concept in conservation biology for measuring biodiversity in a particular place and evaluating the risk of extinction for species. Endemism is also of interest in evolutionary biology, because it provides clues about how changes in the environment cause species to undergo range shifts (potentially expanding their range into a larger area or becoming extirpated from an area they once lived), go extinct, or diversify into more species.

The Moenave Formation is a Mesozoic geologic formation, in the Glen Canyon Group. It is found in Utah and Arizona.

The Moenave was deposited on an erosion surface on the Chinle Formation following an early Jurassic uplift and unconformity that represents about ten million years of missing sedimentation. Periodic incursions of shallow seas from the north during the Jurassic flooded parts of Wyoming, Montana, and a northeast–southwest trending trough on the Utah/Idaho border. The Moenave was deposited in a variety of river, lake, and flood-plain environments, near the ancient Lake Dixie.

Utah is a landlocked state in the Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northeast, Idaho to the north, and Nevada to the west. In comparison to all the U.S. states and territories, Utah, with a population of just over three million, is the 13th-largest by area, the 30th-most populous, and the 11th-least densely populated. Urban development is mostly concentrated in two regions: the Wasatch Front in the north-central part of the state, which includes the state capital, Salt Lake City, and is home to roughly two-thirds of the population; and Washington County in the southwest, which has approximately 180,000 residents. Most of the western half of Utah lies in the Great Basin.

Utah has been inhabited for thousands of years by various indigenous groups, such as the ancient Puebloans, the Navajo, and the Ute. The first Europeans to arrive – in the mid-16th century – were the Spanish. Because of the region's challenging geography and harsh climate, it only became a peripheral part of New Spain (and later of Mexico). Even while it was Mexican territory, many of the Utah region's earliest European settlers were from the United States; notable among these were Mormons who were fleeing marginalization and persecution in the United States and arrived via the so-called Mormon Trail. In 1848, after the Mexican–American War, the region was annexed by the U.S., becoming part of the Utah Territory, which included what later became Colorado and Nevada. Disputes between the dominant Mormon community and the federal government delayed Utah's admission as a state: in 1896, after it agreed to outlaw polygamy, it was admitted as the 45th state.

A wildfire, forest fire, or a bushfire is an unplanned and uncontrolled fire in an area of combustible vegetation. Some natural forest ecosystems depend on wildfire. Modern forest management often engages in prescribed burns to mitigate fire risk and promote natural forest cycles. However, controlled burns can turn into wildfires by mistake.

Wildfires can be classified by cause of ignition, physical properties, combustible material present, and the effect of weather on the fire. Wildfire severity results from a combination of factors such as available fuels, physical setting, and weather. Climatic cycles with wet periods that create substantial fuels, followed by drought and heat, often precede severe wildfires. These cycles have been intensified by climate change, and can be exacerbated by curtailment of mitigation measures (such as budget or equipment funding), or sheer enormity of the event.

The Kitt Peak National Observatory (KPNO) is a United States astronomical observatory located on Kitt Peak of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono Oʼodham Nation, 88 kilometers (55 mi) west-southwest of Tucson, Arizona. With more than twenty optical and two radio telescopes, it is one of the largest gatherings of astronomical instruments in the Earth's northern hemisphere.

Kitt Peak National Observatory was founded in 1958. It is home to what was the largest solar telescope in the world, and many large astronomical telescopes of the late 20th century in the United States.

Southern California (commonly shortened to SoCal) is a geographic and cultural region that generally comprises the southern portion of the U.S. state of California. Its densely populated coastal region includes Greater Los Angeles (the second-most populous urban agglomeration in the United States) and San Diego County (the second-most populous county in California). The region generally contains ten of California's 58 counties: Los Angeles, San Diego, Orange, Riverside, San Bernardino, Kern, Ventura, Santa Barbara, San Luis Obispo, and Imperial counties.

Although geographically smaller than Northern California in land area, Southern California has a higher population, with 23.76 million residents as of the 2020 census. The sparsely populated desert region of California occupies a significant portion of the area: the Colorado Desert, along with the Colorado River, is located on Southern California's eastern border with Arizona, and the Mojave Desert shares a border with Nevada to the northeast. Southern California's southern border with Baja California is part of the Mexico–United States border.

California (/ˌkælɪˈfɔːrniə/) is a state in the Western United States that lies on the Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares an international border with the Mexican state of Baja California to the south. With almost 40 million residents across an area of 163,696 square miles (423,970 km), it is the largest state by population, third-largest state by area and the largest state economy in the U.S., with a GDP of approximately $4.1 trillion.

Prior to European colonization, California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. European exploration in the 16th and 17th centuries led to the colonization by the Spanish Empire. The area became a part of Mexico in 1821, as a result of its successful war for independence. Following the U.S. conquest of California, part of the Mexican-American War, California was ceded to the United States in 1848. The California gold rush started in 1848 and led to social and demographic changes, including the California genocide. It organized itself and was admitted as the 31st state in 1850 as a free state, following the Compromise of 1850.

The international boundary separating Mexico and United States extends from the Pacific Ocean to the Gulf of Mexico. The border traverses a variety of terrains, ranging from urban areas to deserts. It is the most frequently crossed border in the world, with approximately 350 million documented crossings annually. Illegal crossing of the border to enter the United States has caused the Mexico–United States border crisis. It is one of two international borders that the United States has, the other being the northern Canada–United States border; Mexico has two other borders: with Belize and with Guatemala.

Four American Sun Belt states border Mexico: California, Arizona, New Mexico and Texas. One definition of Northern Mexico includes only the six Mexican states that border the U.S.: Baja California, Chihuahua, Coahuila, Nuevo León, Sonora and Tamaulipas. The total length of the continental border is 3,145 kilometers (1,954 miles). From the Gulf of Mexico, it follows the course of the Rio Grande (Río Bravo del Norte) to the border crossing at Ciudad Juárez, Chihuahua, and El Paso, Texas. Westward from El Paso–Juárez, it crosses vast tracts of the Chihuahuan and Sonoran deserts to the Colorado River Delta and San Diego–Tijuana, before reaching the Pacific Ocean.

Nevada (/nəˈvædə/ nə-VAD-ə; Spanish: [neˈβaða] ) is a landlocked state in the Western United States. It is also sometimes placed in the Mountain West and Southwestern United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, the 32nd-most populous, and the ninth-least densely populated U.S. state. Nearly three-quarters of Nevada's population live in Clark County, which contains the Las Vegas–Paradise metropolitan area, including three of the state's four largest incorporated cities. Nevada's capital is Carson City. Las Vegas is the largest city in the state. Nevada is the westernmost U.S. state without coastline and also the westernmost landlocked first-level country subdivison in the Americas.

Nevada is officially known as the "Silver State" because of the importance of silver to its history and economy. It is also known as the "Battle Born State" because it achieved statehood during the Civil War (the words "Battle Born" also appear on its state flag); due to the presidency of Abraham Lincoln, the Union benefited immensely from the support of newly awarded statehood by the infusion of the monetary support of nearly $400 million in silver ore generated at the time by the Comstock Lode. It is also known as the "Sagebrush State", for the native plant of the same name; and as the "Sage-hen State". The state's name means "snowy" in Spanish, referring to Nevada's extensive number of mountain ranges capped with snow in winter, which help make Nevada among the highest US states by mean altitude. These include the Carson Range portion of the Sierra Nevada (and about 1/3 of Lake Tahoe by surface area), as well as the Toiyabe Range, Ruby Mountains, and Spring Mountains (which exemplify the sky islands of the Great Basin montane forests), in western, central, northeastern, and southern Nevada, respectively. Nevada is the driest U.S. state, both lying in the rain shadow of the Sierra Nevada and receiving among the highest solar irradiance of any U.S. state, and is thus largely desert and semi-arid. Nevada comprises the majority of the Great Basin, as well as a large portion of the Mojave Desert. In 2020, 80.1% of the state's land was managed by various jurisdictions of the U.S. federal government, both civilian and military.

A nonbuilding structure, often referred to simply as a structure, is any built structure or construction structure that is not a building, i.e. not designed for continuous human occupancy. The term is particularly used by architects, structural engineers, and mechanical engineers to distinguish load-bearing structures not designed for continuous human occupancy.

The Grand Canyon is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is 277 miles (446 km) long, up to 18 miles (29 km) wide and attains a depth of over a mile (6,093 feet or 1,857 meters).

The canyon and adjacent rim are contained within Grand Canyon National Park, the Kaibab National Forest, Grand Canyon–Parashant National Monument, the Hualapai Indian Reservation, the Havasupai Indian Reservation and the Navajo Nation. President Theodore Roosevelt was a major proponent of the preservation of the Grand Canyon area and visited it on numerous occasions to hunt and enjoy the scenery.

The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that includes Arizona and New Mexico, along with adjacent portions of California, Colorado, Nevada, Oklahoma, Texas, and Utah. The largest cities by metropolitan area are Phoenix, Las Vegas, El Paso, Albuquerque, and Tucson. Before 1848, in the historical region of Santa Fe de Nuevo México as well as parts of Alta California and Coahuila y Tejas, settlement was almost non-existent outside of New Mexico's pueblos and Spanish or Mexican municipalities. Much of the area had been a part of New Spain and Mexico until the United States acquired the area through the Treaty of Guadalupe Hidalgo in 1848 and the smaller Gadsden Purchase in 1854.

While the region's boundaries are not officially defined, there have been attempts to do so. One such definition is from the Mojave Desert in California in the west (117° west longitude) to Carlsbad, New Mexico, in the east (104° west longitude); another says that it extends from the Mexico–United States border in the south to the southern areas of Colorado, Utah, and Nevada in the north (39° north latitude). In another definition, the core Southwestern U.S. includes only the states of Arizona and New Mexico; others focus on the land within the old Spanish and Mexican borders of the Nuevo México Province or the later American New Mexico Territory.

The geography of Mexico describes the geographic features of Mexico, a country in the Americas. Mexico is located at about 23° N and 102° W in the southern portion of North America. From its farthest land points, Mexico is a little over 3,200 km (2,000 mi) in length. Mexico is bounded to the north by the United States (specifically, from west to east, by California, Arizona, New Mexico, and Texas), to the west and south by the Pacific Ocean, to the east by the Gulf of Mexico, and to the southeast by Belize, Guatemala, and the Caribbean Sea. The northernmost constituent of Latin America, it is the most populous Spanish-speaking country in the world. Mexico is the world's 13th largest country, three times the size of Texas.

Almost all of Mexico is on the North American Plate, with small parts of the Baja California Peninsula in the northwest on the Pacific and Cocos Plates. Some geographers include the portion east of the Isthmus of Tehuantepec including the Yucatán Peninsula within North America. This portion includes Campeche, Chiapas, Tabasco, Quintana Roo, and Yucatán, representing 12.1 percent of the country's total area. Alternatively, the Trans-Mexican Volcanic Belt may be said to delimit the region physiographically on the north. Geopolitically, Mexico is generally not considered part of Central America. Politically, Mexico is divided into thirty-two states.

Petrified wood (from Ancient Greek πέτρα meaning 'rock' or 'stone'; literally 'wood turned into stone'), is the name given to a special type of fossilized wood, the fossilized remains of terrestrial vegetation. Petrifaction is the result of a tree or tree-like plants having been replaced by stone via a mineralization process that often includes permineralization and replacement. The organic materials making up cell walls have been replicated with minerals (mostly silica in the form of opal, chalcedony, or quartz). In some instances, the original structure of the stem tissue may be partially retained. Unlike other plant fossils, which are typically impressions or compressions, petrified wood is a three-dimensional representation of the original organic material.

The petrifaction process occurs underground, when wood becomes buried in water or volcanic ash. The presence of water reduces the availability of oxygen which inhibits aerobic decomposition by bacteria and fungi. Mineral-laden water flowing through the sediments may lead to permineralization, which occurs when minerals precipitate out of solution filling the interiors of cells and other empty spaces. During replacement, the plant's cell walls act as a template for mineralization. There needs to be a balance between the decay of cellulose and lignin and mineral templating for cellular detail to be preserved with fidelity. Most of the organic matter often decomposes, however some of the lignin may remain. Silica in the form of opal-A, can encrust and permeate wood relatively quickly in hot spring environments. However, petrified wood is most commonly associated with trees that were buried in fine grained sediments of deltas and floodplains or volcanic lahars and ash beds. A forest where such material has petrified becomes known as a petrified forest.

In the United States, a governor serves as the chief executive and commander-in-chief in each of the fifty states and in the five permanently inhabited territories, functioning as head of state and head of government therein. While like all officials in the United States, checks and balances are placed on the office of the governor, significant powers may include ceremonial head of state (representing the state), executive (overseeing the state's government), legislative (proposing, and signing or vetoing laws), judicial (granting state law pardons or commutations), and military (overseeing the militia and organized armed forces of the state). As such, governors are responsible for implementing state laws and overseeing the operation of the state executive branch. As state leaders, governors advance and pursue new and revised policies and programs using a variety of tools, among them executive orders, executive budgets, and legislative proposals and vetoes. Governors carry out their management and leadership responsibilities and objectives with the support and assistance of department and agency heads, many of whom they are empowered to appoint. A majority of governors have the authority to appoint state court judges as well, in most cases from a list of names submitted by a nominations committee.

All with the exception of five states and one territory (Arizona, Maine, New Hampshire, Oregon, Puerto Rico, and Wyoming) have a lieutenant governor. The lieutenant governor succeeds to the gubernatorial office (the powers and duties but not the office, in Massachusetts and West Virginia), if vacated by impeachment, death, or resignation of the previous governor. Lieutenant governors also serve as unofficial acting state governors in case the incumbent governors are unable to fulfill their duties, and they often serve as presiding officers of the upper houses of state legislatures. In such cases, they cannot participate in political debates, and they have no vote whenever these houses are not equally divided.

The Inland Empire (commonly abbreviated as the IE) is a metropolitan area and region inland of and adjacent to coastal Southern California in the Greater Los Angeles area, focusing around the cities in Riverside and San Bernardino county with Los Angeles County and Orange County to the west. The region, at its narrowest definition, includes the cities of northwestern Riverside County and southwestern San Bernardino County that are part of the contiguous urbanized area of Greater Los Angeles. It is sometimes considered to include the desert communities of the Coachella and Victor Valleys, respectively on the other sides of the San Gorgonio Pass and San Bernardino Mountains from the Santa Ana River watershed that creates the majority of the Inland Empire. A much wider definition includes the entireties of Riverside and San Bernardino counties, stretching east to the Nevada and Arizona borders and covering a larger area than West Virginia; this definition is primarily used by the US Census Bureau, which exclusively delineates metropolitan areas at the county level.

The U.S. Census Bureau–defined Riverside–San Bernardino–Ontario metropolitan area, which comprises Riverside County and San Bernardino, California, covers more than 27,000 sq mi (70,000 km) and had a population of about 4.6 million in 2020. At the end of the 19th century, the Inland Empire was a major center of agriculture, including citrus, dairy and winemaking. Agriculture declined through the 20th century and a rapidly increasing population, helped by families migrating in search of affordable housing, has led to more residential, industrial and commercial development since the 1970s.

In the United States, tourism is a large industry that serves millions of international and domestic tourists yearly. Foreigners visit the U.S. to see natural wonders, cities, historic landmarks, and entertainment venues. Americans seek similar attractions, as well as recreation and vacation areas.

Tourism in the United States grew rapidly in the form of urban tourism during the late nineteenth and early twentieth centuries. By the 1850s, tourism in the United States was well established both as a cultural activity and as an industry. New York City, Los Angeles, Chicago, Boston, Philadelphia, Washington, D.C., and San Francisco, all major U.S. cities, have attracted numerous tourists since the 1890s. By 1915, city touring had marked significant shifts in the way Americans perceived, organized, and moved.