Serpentine soil is an uncommon soil type produced by weathered ultramafic rock such as peridotite and its metamorphic derivatives such as serpentinite. More serpentine soil contains minerals of the serpentine subgroup antigorite and chrysotile or white asbestos, all of which are found in ultramafic rocks; the term "serpentine" is used to refer to both the soil type and the mineral group which forms its parent materials. Serpentine soils exhibit distinct chemical and physical properties and are regarded as poor soils; the soil is reddish, brown, or gray in color due to its high iron and low organic content. Geologically, areas with serpentine bedrock are characteristically steep and vulnerable to erosion, which causes many serpentine soils to be rather shallow; the shallow soils and sparse vegetation lead to dry conditions. Due to their ultramafic origin, serpentine soils suffer from a low calcium-to-magnesium ratio and lack many essential nutrients such as nitrogen and potassium. Serpentine soils contain high concentrations of heavy metals, including chromium, iron and nickel.
Together, these factors create serious ecological challenges for plants living in serpentine soils. Serpentinite is a meta-igneous rock formed by the metamorphic reaction of olivine-rich rock, with water. Serpentinite has a mottled, greenish-gray or bluish-gray color and is waxy to the touch; the rock contains white streaks of chrysotile running through it, which are a type of occurring asbestos. Asbestos is linked to an array of human health conditions such as mesothelioma from long time exposure of breathing in the dust particles. Caution should be taken when working in serpentine soils or when working with crushed serpentine rocks. Serpentinite most forms in oceanic crust near the surface of the earth where water circulates in cooling rock near mid-ocean ridges: masses of the resulting ultramafic rock are found in ophiolites incorporated in continental crust near present and past tectonic plate boundaries. Serpentine soils are derived from ultramafic rocks. Ultramafic rocks are metamorphic rocks that contain more than 70 % iron or magnesium.
Serpentine soils are distributed on Earth, in part mirroring the distribution of ophiolites. There are outcroppings of serpentine soils in the Balkan Peninsula, Alps and New Caledonia. In North America, serpentine soils are present in small but distributed areas on the eastern slope of the Appalachian mountains in the eastern United States. However, California has the majority of the continent's serpentine soils. Ecologically, serpentine soils have three main traits: poor plant productivity, high rates of endemism, vegetation types which are distinct from neighboring areas. Serpentine plant communities range from moist bogs and fens to rocky barrens, must be able to tolerate the harsh environmental conditions of such poor soil; as a result, they are drastically different than non-serpentine soil areas bordering the serpentine soils. Vegetative characteristics are shared among the types of flora found on serpentine soils, they will exhibit a "stunted" growth habit, with dull waxy, gray-green leaves, which allow for water retention and sunlight reflection respectively.
Other possible phenotypic traits include pigmented stems and a carnivorous nature as seen in the Darlingtonia californica. Some examples of common serpentine tolerant plants include: Gray Pine, California Lilac, Live-Oak, California Redbud, California Buckeye, California laurel. Areas of serpentine soil are home to diverse plants, many of which are rare or endangered species such as Acanthomintha duttonii, Pentachaeta bellidiflora, Phlox hirsuta. In California, 45% of the taxa associated with serpentine are rare or endangered. In California, shrubs such as leather oak and coast whiteleaf manzanita are typical of serpentine soils. In order to overcome the chemical and physical challenges presented by serpentine soils, plants have developed tolerances to drought, heavy metals, limited nutrients. Low calcium:magnesium ratios cause limited root growth and root activity, weak cell membranes, reduced uptake of essential nutrients. An adaptive mechanism to high magnesium soils allocates more resources to deep-growing roots.
Heavy metals stunt growth, induce iron deficiency, cause chlorosis, restrict root development. Multiple adaptive mechanisms to heavy metals include the exclusion of metals by restricting the uptake by the roots, compartmentalization of metals in various organs, or the development of toxicity tolerance. In nitrogen-poor sites, physiological effects on plants include impaired protein synthesis, reduced leaf turgor, reduced leaf and tiller number, reduced growth rate, low seed yield. Low phosphorus levels cause similar effects of low nitrogen but cause reduced seed size, lower root to shoot ratios, increased water stress. Low soil moisture causes reduced nutrient uptake and transport, decreased stomatal opening and reduced photosynthetic capacity, reduces plant growth and productivity. Serpentine plants have developed root systems to facilitate uptake of water and nutrients. For example, Noccaea fendleri is a hyper-accumulator of nickel and Sedum laxum ssp. expresses succulence. In some cases, symbioses with serpentine tolerant ectomycorrhizal help fa
Loma Prieta is 3,790 feet high and is the highest peak in the Santa Cruz Mountains in Northern California. The peak is on private property about 11 miles west of Morgan Hill in Santa Clara County; the dirt road to the summit is gated, but the tower maintainers do not mind hikers. From 1976 through 1990 amateur astronomer Donald Machholz set up his telescope an average of 120 times a year on the south slope of this mountain to search for comets. From this site he discovered three new comets that bear his name, including Periodic Comet Machholz 1 96P/Machholz on May 12, 1986; the first official West Coast Messier marathon was conducted from this site in March 1979. The epicenter of the 1989 Loma Prieta earthquake was near the mountain; the mountain was the longtime site for the transmitter tower of San Jose television station KNTV. It moved its transmitter 83 kilometres northwest to San Bruno Mountain in September 2005, after it became the Bay Area's NBC affiliate. Loma Prieta is the tallest peak in the Santa Cruz Mountains and it is common to see snow on the mountain during the winter.
List of summits of the San Francisco Bay Area "Map of Loma Prieta"
Black Mountain (near Los Altos, California)
Black Mountain is a summit on Monte Bello Ridge in the Santa Cruz Mountains of west Santa Clara County, south of Los Altos and Los Altos Hills, west of Cupertino. It is located on the border between Rancho San Antonio Open Space Preserve and Monte Bello Open Space Preserve, with the summit located in the former. Early Spanish explorers named tree- or chaparral-covered summits which look black in the distance Loma Prieta, from the Spanish; the Spanish called the middle portion of the Santa Cruz Mountains the Sierra Morena meaning, extending from Half Moon Bay Road south to a gap at Lexington Reservoir, which includes a summit called Sierra Morena. There are over 100 "Black Mountains" in California. After extensive logging operations in the nineteenth century, Italian farmers and winemakers settled on the flanks of Montebello Ridge. Dairies in the Santa Cruz Mountains supplied much of the milk for the Peninsula. There was a large dairy near what is now the Montebello Open Space Preserve's main parking area on Page Mill Road, cattle grazed the slopes of Black Mountain.
Ranch buildings dotted the landscape. Oseo Perrone, a physician and immigrant from Mattarana, La Spezia Province, came to San Francisco in 1881, became interested in viticulture and purchased a large ranch at 2,600 feet on Black Mountain in 1885 where he, his nephew of the same name, began production of Montebello Winery wine in 1892. George Morell, founding publisher of the Palo Alto Times and a Trustee of Stanford University, bought the Black Mountain Ranch on the mountain's summit in 1940. "Nature in the raw" is what led Mr. Morell to buy Black Mountain Ranch, according to his essay, "History of Black Mountain and Monte Bello Ridge," written in 1959. Morell donated the land comprising the former Johnson, Morell ranches to Stanford University. In 1975, when the Black Mountain Ranch lands were acquired by the Midpeninsula Regional Open Space District from Stanford, a commune of about 100 people, called "The Land", were evicted; the Land lived along the Canyon Trail from Page Mill Road to Indian Creek and built a variety of dwellings on platforms scattered amongst the oak woodlands and secluded canyons.
A large ranch building was used as a central dining hall, maintained a woodworking shop, a stained-glass workshop, a food store selling bulk items. Commune members grew their own food in gardens, engaged in artistic pursuits, gathered for holiday dinners and celebrations. Three creeks, each with an interesting history, spring from Black Mountain and flow to southwest San Francisco Bay. Stevens Creek originates in the Montebello Open Space Reserve on the west flank of the mountain and flows southeast north to the Bay. Stevens Creek was called Arroyo San José de Cupertino by Spanish explorer Juan Bautista de Anza, who camped along the creek on his expedition from Monterey to San Francisco. Anza completed the first overland route to San Francisco Bay when he and Father Pedro Font sighted the bay from a prominent knoll near the entry of Rancho San Antonio County Park. In Anza's diary on March 25, 1776, he states that he "arrived at the "Arroyo San José de Cupertino", useful only for travelers. Here we halted for the night.
From this place we have seen at our right the estuary which runs from the port of San Francisco." The Arroyo San José de Cupertino became Cupertino Creek, but was re-named for Elijah Stephens, a South Carolina-born blacksmith and trapper who settled on Cupertino Creek in 1848. Stephens renamed his 160-acre property at the base of Black Mountain "Blackberry Farm". Stephens is notable for being the captain of the Stephens-Townsend-Murphy Party, the first wagon train to cross the Sierra Nevada. Adobe Creek named Yeguas Creek San Antonio Creek, flows down Black Mountain's north flank to the Bay at the Palo Alto Flood Basin, just west of the Bay Trail on the levee separating it from Charleston Slough; the founders of Adobe Systems, a software company, lived next to Adobe Creek in Los Altos, named their company after the creek. The upper watershed of Adobe Creek is protected by the Hidden Villa, a nonprofit educational organization founded by Frank and Josephine Duveneck, who purchased the land in 1924 and offered it as a gathering place for discussion and incubation of social reform.
Over the following decades, the Duvenecks established the first Hostel on the Pacific Coast, the first multiracial summer camp, Hidden Villa's Environmental Education Program. Permanente Creek, named Río Permanente by early Spanish explorers because of its perennial flow, descends the east flank of Black Mountain courses north to the Bay at the Mountain View Slough. Permanente Creek is the namesake for Kaiser Permanente. Bess Kaiser and her spouse, industrialist Henry Kaiser, had a lodge on the creek's headwaters above the large Permanente Quarry and Cement Plant, and, in 1945, Bess felt that the name of their attractive and dependable stream would be a good name for their medical program at the shipyards; that medical program became Kaiser Permanente. Rainfall on the summit of Black Mountain averages 40 inches per year, much higher than the Santa Clara Valley which lies in its rain shadow. From its name, Black Mountain's dark summit was once covered with forest or chaparral instead of the current grasslands.
Evidence of a large historic Coast Douglas-fir (Pseudotsuga menziesii
Montara is a census-designated place in San Mateo County, United States. The population was 2,909 at the 2010 census. Nearby communities include Moss Princeton-by-the-Sea. According to historical sources, the name "Montoro" was used for Montara Mountain and Montara Point by the Whitney Survey known as the California Geological Survey, in 1867. In 1869, the Coast Survey referred to the area with its current name; the name is thought to be a misspelling of several Spanish words that describe mountains and forests, such as montuoso and montaña. It could refer to a corruption of the Spanish word "Montosa". Montara is located at 37°32′23″N 122°30′23″W 20 miles south of San Francisco and 50 miles north of Santa Cruz, California. Neighboring towns include Pacifica to the north, Moss Beach, El Granada, Half Moon Bay to the south. According to the United States Census Bureau, the CDP has a total area of 3.9 square miles, all of it land. The rare and endangered species Hickman's potentilla occurs at the northern extremity of Montara on the slopes above Martini Creek at elevations ranging from 32 to 410 feet.
Nearby Montara Mountain, part of the Santa Cruz Mountains, rises to an elevation of 1,898 feet above sea level. The mountain is accessible by a gravel fire road. On a few occasions light snowfall has fallen on the upper reaches of the mountain; the town is surrounded by open space and a popular recreation area includes Montara State Beach. The nearly mile long stretch of sand drops steeply into the ocean making it hazardous for swimming, it is, however, a popular surfing destination for experienced surfers. 10-15+ ft. waves can be common during winter storm swells. Montara State Marine Reserve & Pillar Point State Marine Conservation Area extend offshore from Montara. Like underwater parks, these marine protected areas help conserve ocean wildlife and marine ecosystems. Montara enjoys exceptionally mild weather throughout the year. Typical of Northern California, most of the rainfall falls from November through April totaling more than 27 inches. Due to its proximity to the Pacific Ocean, heavy fogs and low overcasts are common throughout the year, sometimes producing light drizzle.
Stray showers sometimes occur during the dry summer months. January, the coldest month has high temperatures in the upper fifties and low temperatures in the middle forties. Freezing temperatures are rare near the ocean. September, the warmest month has high temperatures in the upper sixties and lows in the lower fifties. Temperatures exceed 90 °F and whenever there are daytime temperatures above 80 °F it still cools to the fifties at night. During experimental observations by a U. S. Geological Survey volunteer, the highest temperature was an amazing 100 °F and the lowest was 31 °F; the nearest official National Weather Service station is at Half Moon Bay. An automated weather station was set up in Montara, providing regular observations on the National Weather Service's website, weather.gov. The 2010 United States Census reported that Montara had a population of 2,909; the population density was 750.1 people per square mile. The racial makeup of Montara was 2,491 White, 16 African American, 21 Native American, 142 Asian, 1 Pacific Islander, 97 from other races, 141 from two or more races.
Hispanic or Latino of any race were 324 persons. The Census reported that 2,909 people lived in households, 0 lived in non-institutionalized group quarters, 0 were institutionalized. There were 1,109 households, out of which 351 had children under the age of 18 living in them, 666 were opposite-sex married couples living together, 77 had a female householder with no husband present, 46 had a male householder with no wife present. There were 59 unmarried opposite-sex partnerships, 17 same-sex married couples or partnerships. 209 households were made up of individuals and 72 had someone living alone, 65 years of age or older. The average household size was 2.62. There were 789 families; the population was spread out with 617 people under the age of 18, 169 people aged 18 to 24, 622 people aged 25 to 44, 1,145 people aged 45 to 64, 356 people who were 65 years of age or older. The median age was 46.0 years. For every 100 females, there were 92.5 males. For every 100 females age 18 and over, there were 90.0 males.
There were 1,167 housing units at an average density of 300.9 per square mile, of which 898 were owner-occupied, 211 were occupied by renters. The homeowner vacancy rate was 0.9%. 2,409 people lived in owner-occupied housing units and 500 people lived in rental housing units. As of the census of 2000, there were 2,950 people, 1,010 households, 756 families residing in the CDP; the population density was 751.0 people per square mile. There were 1,034 housing units at an average density of 263.2 per square mile. The racial makeup of the CDP in 2010 was 79.2% non-Hispanic White, 0.5% non-Hispanic African American, 0.3% Native American, 4.8%
Adobe Creek (Santa Clara County, California)
Adobe Creek is a 14.2-mile-long northward-flowing stream originating on Black Mountain in Santa Clara County, United States. It courses through the cities of Los Altos Hills, Los Altos, Palo Alto. Adobe Creek was perennial and hosted runs of steelhead trout entering from southwestern San Francisco Bay; the Ohlone people were the original inhabitants of Adobe Creek. A large shell mound which once had a group of Indian huts was found near Adobe Creek in Palo Alto. Evidence of a smaller settlement within Los Altos was uncovered in 1971, when an Ohlone burial ground with skeletons—one with ceremonial beads—was uncovered by new construction along Adobe Creek near O'Keefe Lane; the site had other artifacts, an archeological dig was mounted by Foothill College. Around this same time, an Ohlone basket was discovered buried in the Creek bank further north; the O'Keefe site has a historical plaque marking the historic site. On the 1862 Allardt Map the upper creek is called Arroyo San Antonio and the lower creek is called Arroyo de las Yeguas.
Yeguas is Spanish for "mare", the Mission Santa Clara named it that because they built a corral for mares along the creek's banks near the Bay. Juan Prado Mesa renamed it San Antonio Creek when he was granted Rancho San Antonio in 1839 by Governor Juan Bautista Alvarado; the Adobe Creek name appears as early as 1855 on an official surveyor's map, which lists both the Adobe and San Antonio names for the creek. During the secularization of the missions in the 1830s, Alvarado parceled out much of their land to prominent Californios via land grants. Mesa was a soldier stationed at the Presidio of San Francisco who had become alfarez in 1837, he built a large square adobe, which lasted well into the twentieth century as a crumbling ruin long thought of as a fortification. The site today is on a hill on the southeast side of El Monte Avenue near Summerhill Avenue in Los Altos, most of, located on the territory of the Rancho; the upper creek originates in the historic Rancho La Purisima Concepcion, granted by Governor Alvarado in 1840 to Jose Gorgonio, an Indian living at Mission Santa Clara.
Gorgonio moved to the west bank of Adobe Creek near Fremont Avenue in Los Altos Hills. Much of the town of Los Altos Hills, California was located on this Rancho. In 1844 Rancho La Purisima Concepcion was sold to Juana Briones de Miranda, whose family members had accompanied both the Gaspar de Portolà and the Juan Bautista de Anza Expeditions, her uniquely constructed wood-framed, rammed-earth and adobe brick house, believed to have been built by American desertee sailors, is located at 4155 Old Adobe Road on the border between Palo Alto and Los Altos Hills, is marked by a historical marker at the corner of Old Adobe Road and Old Trace Lane. Designated a California State Historical Landmark in 1954, the 160-year-old Juana Briones home was scheduled for demolition in 2007 because of damage to it by the Loma Prieta earthquake in 1989. In 2009, it still stands and has been documented with a Historic American Buildings Survey. After 1831, Mexican rancho owners would logically erect their dwellings on or near creeks.
Locally, Juan Prado's adobe was near Adobe Juanita Briones' adobe was near Barron Creek. Because they were permanent features of the landscape, creeks were used as Rancho boundaries; this was true locally, where the Mexican diseño show Adobe Creek as the boundary between Rancho San Antonio and Rancho La Purisima Concepcion. When Americans took over in 1850, speculators bought much of this land. Much of it became large self-contained ranches—typically running cattle & growing crops like wheat, barley & oats that required little or no irrigation; that changed in a few decades when it was discovered that vineyards could thrive here. Such agriculture of course used more water. Local land was cut progressively into smaller holdings, until most of it was subdivided as the population increased; this meant more and more wells, including large ones dug along Adobe Creek by early water companies to serve the little town of Los Altos. The water table shrank as a result, alarms about this development appeared, at least as early as the 1920s.
In the early 1930s, the Los Altos News reported that the water table, which stood at 120 feet in 1898, was now down to 335 feet. The Trust for Hidden Villa, is a nonprofit educational organization founded by Frank and Josephine Duveneck, who purchased most of the land comprising the upper Adobe Creek watershed in 1924, they opened Hidden Villa as a gathering place for discussion and incubation of social reform. Over the following decades, the Duvenecks established the first Hostel on the Pacific Coast, the first multiracial summer camp, Hidden Villa's Environmental Education Program, all on the creek's upper reaches; the Juan Prado Mesa Preserve in Los Altos Hills between Dawson Drive and Stonebrook Road, Hale Creek and Neary Quarry was created in 1970 and named for the original holder of the land grant. Adobe Creek Lodge, an English country-style mansion, was built by Consolidated Chemicals vice-president Milton Haas in 1935, it was a destination resort in the 1940s. Bandleaders Jimmy Dorsey and Harry James played there.
The founders of Adobe Systems, a software company, lived next to Adobe Creek in Los Altos, named their company after the creek. The founder of Los Altos, Paul Shoup picked a premium lot on Adobe Creek for his home from the ranch lands he helped purchase from Sarah Winchester that became the community of Los Altos; the Paul Shoup House on Adobe Creek is the first property in Los Altos to be listed on the National Register of Historic Places. Adobe Creek drains about 11
The rainbow trout is a trout and species of salmonid native to cold-water tributaries of the Pacific Ocean in Asia and North America. The steelhead is an anadromous form of the coastal rainbow trout or Columbia River redband trout that returns to fresh water to spawn after living two to three years in the ocean. Freshwater forms that have been introduced into the Great Lakes and migrate into tributaries to spawn are called steelhead. Adult freshwater stream rainbow trout average between 1 and 5 lb, while lake-dwelling and anadromous forms may reach 20 lb. Coloration varies based on subspecies and habitat. Adult fish are distinguished by a broad reddish stripe along the lateral line, from gills to the tail, most vivid in breeding males. Wild-caught and hatchery-reared forms of this species have been transplanted and introduced for food or sport in at least 45 countries and every continent except Antarctica. Introductions to locations outside their native range in the United States, Southern Europe, New Zealand and South America have damaged native fish species.
Introduced populations may affect native species by preying on them, out-competing them, transmitting contagious diseases, or hybridizing with related species and subspecies, thus reducing genetic purity. The rainbow trout is included in the list of the top 100 globally invasive species. Nonetheless, other introductions into waters devoid of any fish species or with depleted stocks of native fish have created sport fisheries such as the Great Lakes and Wyoming's Firehole River; some local populations of specific subspecies, or in the case of steelhead, distinct population segments, are listed as either threatened or endangered under the Endangered Species Act. The steelhead is the official state fish of Washington; the scientific name of the rainbow trout is Oncorhynchus mykiss. The species was named by German naturalist and taxonomist Johann Julius Walbaum in 1792 based on type specimens from the Kamchatka Peninsula in Siberia. Walbaum's original species name, was derived from the local Kamchatkan name used for the fish, mykizha.
The name of the genus is from the Greek onkos and rynchos, in reference to the hooked jaws of males in the mating season. Sir John Richardson, a Scottish naturalist, named a specimen of this species Salmo gairdneri in 1836 to honor Meredith Gairdner, a Hudson's Bay Company surgeon at Fort Vancouver on the Columbia River who provided Richardson with specimens. In 1855, William P. Gibbons, the curator of Geology and Mineralogy at the California Academy of Sciences, found a population and named it Salmo iridia corrected to Salmo irideus; these names faded once it was determined that Walbaum's description of type specimens was conspecific and therefore had precedence. In 1989, morphological and genetic studies indicated that trout of the Pacific basin were genetically closer to Pacific salmon than to the Salmos – brown trout or Atlantic salmon of the Atlantic basin. Thus, in 1989, taxonomic authorities moved the rainbow and other Pacific basin trout into the genus Oncorhynchus. Walbaum's name had precedence, so the species name Oncorhynchus mykiss became the scientific name of the rainbow trout.
The previous species names irideus and gairdneri were adopted as subspecies names for the coastal rainbow and Columbia River redband trout, respectively. Anadromous forms of the coastal rainbow trout or redband trout are known as steelhead. Subspecies of Oncorhynchus mykiss are listed below as described by fisheries biologist Robert J. Behnke. Resident freshwater rainbow trout adults average between 1 and 5 lb in riverine environments, while lake-dwelling and anadromous forms may reach 20 lb. Coloration varies between regions and subspecies. Adult freshwater forms are blue-green or olive green with heavy black spotting over the length of the body. Adult fish have a broad reddish stripe along the lateral line, from gills to the tail, most pronounced in breeding males; the caudal fin is only mildly forked. Lake-dwelling and anadromous forms are more silvery in color with the reddish stripe completely gone. Juvenile rainbow trout display parr marks typical of most salmonid juveniles. In some redband and golden trout forms parr marks are retained into adulthood.
Some coastal rainbow trout and Columbia River redband trout populations and cutbow hybrids may display reddish or pink throat markings similar to cutthroat trout. In many regions, hatchery-bred trout can be distinguished from native trout via fin clips. Fin clipping the adipose fin is a management tool used to identify hatchery-reared fish. Rainbow trout, including steelhead forms spawn in early to late spring when water temperatures reach at least 42 to 44 °F; the maximum recorded lifespan for a rainbow trout is 11 years. Freshwater resident rainbow trout inhabit and spawn in small to moderately large, well oxygenated, shallow rivers with gravel bottoms, they are native to the alluvial or freestone streams that are typical tributaries of the Pacific basin, but introduced rainbow trout have established wild, self-sustaining populations in other river types such as bedrock and spring creeks. Lake resident rainbow trout are found in moderately deep, cool lakes with
The United States of America known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U. S. is the third most populous country. The capital is Washington, D. C. and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico; the State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean; the U. S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The diverse geography and wildlife of the United States make it one of the world's 17 megadiverse countries.
Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago. European colonization began in the 16th century; the United States emerged from the thirteen British colonies established along the East Coast. Numerous disputes between Great Britain and the colonies following the French and Indian War led to the American Revolution, which began in 1775, the subsequent Declaration of Independence in 1776; the war ended in 1783 with the United States becoming the first country to gain independence from a European power. The current constitution was adopted in 1788, with the first ten amendments, collectively named the Bill of Rights, being ratified in 1791 to guarantee many fundamental civil liberties; the United States embarked on a vigorous expansion across North America throughout the 19th century, acquiring new territories, displacing Native American tribes, admitting new states until it spanned the continent by 1848. During the second half of the 19th century, the Civil War led to the abolition of slavery.
By the end of the century, the United States had extended into the Pacific Ocean, its economy, driven in large part by the Industrial Revolution, began to soar. The Spanish–American War and World War I confirmed the country's status as a global military power; the United States emerged from World War II as a global superpower, the first country to develop nuclear weapons, the only country to use them in warfare, a permanent member of the United Nations Security Council. Sweeping civil rights legislation, notably the Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968, outlawed discrimination based on race or color. During the Cold War, the United States and the Soviet Union competed in the Space Race, culminating with the 1969 U. S. Moon landing; the end of the Cold War and the collapse of the Soviet Union in 1991 left the United States as the world's sole superpower. The United States is the world's oldest surviving federation, it is a representative democracy.
The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, other international organizations. The United States is a developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for a quarter of global GDP; the U. S. economy is post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world. The United States is the world's largest importer and the second largest exporter of goods, by value. Although its population is only 4.3% of the world total, the U. S. holds 31% of the total wealth in the world, the largest share of global wealth concentrated in a single country. Despite wide income and wealth disparities, the United States continues to rank high in measures of socioeconomic performance, including average wage, human development, per capita GDP, worker productivity.
The United States is the foremost military power in the world, making up a third of global military spending, is a leading political and scientific force internationally. In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere America in honor of the Italian explorer and cartographer Amerigo Vespucci; the first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq. to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort; the first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. The second draft of the Articles of Confederation, prepared by John Dickinson and completed by June 17, 1776, at the latest, declared "The name of this Confederation shall be the'United States of America'".
The final version of the Articles sent to the states for ratification in late 1777 contains the sentence "The Stile of this Confederacy shall be'The United States of America'". In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence; this draft of the document did not surface unti