Colorado is a state of the Western United States encompassing most of the southern Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains. It is the 8th most extensive and 21st most populous U. S. state. The estimated population of Colorado was 5,695,564 on July 1, 2018, an increase of 13.25% since the 2010 United States Census. The state was named for the Colorado River, which early Spanish explorers named the Río Colorado for the ruddy silt the river carried from the mountains; the Territory of Colorado was organized on February 28, 1861, on August 1, 1876, U. S. President Ulysses S. Grant signed Proclamation 230 admitting Colorado to the Union as the 38th state. Colorado is nicknamed the "Centennial State" because it became a state one century after the signing of the United States Declaration of Independence. Colorado is bordered by Wyoming to the north, Nebraska to the northeast, Kansas to the east, Oklahoma to the southeast, New Mexico to the south, Utah to the west, touches Arizona to the southwest at the Four Corners.
Colorado is noted for its vivid landscape of mountains, high plains, canyons, plateaus and desert lands. Colorado is part of the western and southwestern United States, is one of the Mountain States. Denver is most populous city of Colorado. Residents of the state are known as Coloradans, although the antiquated term "Coloradoan" is used. Colorado is notable for its diverse geography, which includes alpine mountains, high plains, deserts with huge sand dunes, deep canyons. In 1861, the United States Congress defined the boundaries of the new Territory of Colorado by lines of latitude and longitude, stretching from 37°N to 41°N latitude, from 102°02'48"W to 109°02'48"W longitude. After 158 years of government surveys, the borders of Colorado are now defined by 697 boundary markers and 697 straight boundary lines. Colorado and Utah are the only states that have their borders defined by straight boundary lines with no natural features; the southwest corner of Colorado is the Four Corners Monument at 36°59'56"N, 109°2'43"W.
This is the only place in the United States where four states meet: Colorado, New Mexico and Utah. The summit of Mount Elbert at 14,440 feet elevation in Lake County is the highest point in Colorado and the Rocky Mountains of North America. Colorado is the only U. S. state that lies above 1,000 meters elevation. The point where the Arikaree River flows out of Yuma County and into Cheyenne County, Kansas, is the lowest point in Colorado at 3,317 feet elevation; this point, which holds the distinction of being the highest low elevation point of any state, is higher than the high elevation points of 18 states and the District of Columbia. A little less than half of Colorado is flat and rolling land. East of the Rocky Mountains are the Colorado Eastern Plains of the High Plains, the section of the Great Plains within Nebraska at elevations ranging from 3,350 to 7,500 feet; the Colorado plains are prairies but include deciduous forests and canyons. Precipitation averages 15 to 25 inches annually. Eastern Colorado is presently farmland and rangeland, along with small farming villages and towns.
Corn, hay and oats are all typical crops. Most villages and towns in this region boast both a grain elevator. Irrigation water is available from subterranean sources. Surface water sources include the South Platte, the Arkansas River, a few other streams. Subterranean water is accessed through artesian wells. Heavy use of wells for irrigation caused underground water reserves to decline. Eastern Colorado hosts considerable livestock, such as hog farms. 70% of Colorado's population resides along the eastern edge of the Rocky Mountains in the Front Range Urban Corridor between Cheyenne and Pueblo, Colorado. This region is protected from prevailing storms that blow in from the Pacific Ocean region by the high Rockies in the middle of Colorado; the "Front Range" includes Denver, Fort Collins, Castle Rock, Colorado Springs, Pueblo and other townships and municipalities in between. On the other side of the Rockies, the significant population centers in Western Colorado are the cities of Grand Junction and Montrose.
The Continental Divide of the Americas extends along the crest of the Rocky Mountains. The area of Colorado to the west of the Continental Divide is called the Western Slope of Colorado. West of the Continental Divide, water flows to the southwest via the Colorado River and the Green River into the Gulf of California. Within the interior of the Rocky Mountains are several large parks which are high broad basins. In the north, on the east side of the Continental Divide is the North Park of Colorado; the North Park is drained by the North Platte River, which flows north into Nebraska. Just to the south of North Park, but on the western side of the Continental Divide, is the Middle Park of Colorado, drained by the Colorado River; the South Park of Colorado is the region of the headwaters of the South Platte River. In southmost Colorado is the large San Luis Valley, where the headwaters of the Rio Grande are located; the valley sits between the Sangre De Cristo Mountains and San Juan Mountains, consists of large desert lands that run into the mountains.
The Rio Grande drains due south into New Mexico and Texas. Across the Sangre de Cristo Range to the east of the S
Yellow is the color between orange and green on the spectrum of visible light. It is evoked by light with a dominant wavelength of 570–590 nm, it is a primary color in subtractive color systems, used in color printing. In the RGB color model, used to create colors on television and computer screens, yellow is a secondary color made by combining red and green at equal intensity. Carotenoids give the characteristic yellow color to autumn leaves, canaries and lemons, as well as egg yolks and bananas, they protect plants from photodamage. Sunlight has a slight yellowish hue, due to the surface temperature of the sun; because it was available, yellow ochre pigment was one of the first colors used in art. Ochre and orpiment pigments were used to represent gold and skin color in Egyptian tombs in the murals in Roman villas. In the early Christian church, yellow was the color associated with the Pope and the golden keys of the Kingdom, but was associated with Judas Iscariot and was used to mark heretics.
In the 20th century, Jews in Nazi-occupied Europe were forced to wear a yellow star. In China, bright yellow was the color of the Middle Kingdom, could be worn only by the Emperor and his household. According to surveys in Europe and the United States, yellow is the color people most associate with amusement, gentleness and spontaneity, but with duplicity, jealousy, and, in the U. S. with cowardice. In Iran it has connotations of pallor/sickness, but wisdom and connection. In China and many Asian countries, it is seen as the color of happiness, glory and wisdom; the word yellow comes from the Old English geolu, meaning "yellow, yellowish", derived from the Proto-Germanic word gelwaz "yellow". It has the same Indo-European base, gʰel -, as yell; the English term is related to other Germanic words for yellow, namely Scots yella, East Frisian jeel, West Frisian giel, Dutch geel, German gelb, Swedish and Norwegian gul. According to the Oxford English Dictionary, the oldest known use of this word in English is from The Epinal Glossary in 700.
Yellow is found between orange on the spectrum of visible light. It is the color the human eye sees when it looks at light with a dominant wavelength between 570 and 590 nanometers. In color printing, yellow is one of the three colors of ink, along with magenta and cyan, along with black, can be overlaid in the right combination, along with black, to print any full color image.. A particular yellow is used, called Process yellow subtractive primary colors, along with magenta and cyan. Process yellow is not an RGB color, there is no fixed conversion from CMYK primaries to RGB. Different formulations are used for printer's ink, so there can be variations in the printed color, pure yellow ink; the yellow on a color television or computer screen is created in a different way. Traditionally, the complementary color of yellow is purple. Vincent Van Gogh, an avid student of color theory, used combinations of yellow and purple in several of his paintings for the maximum contrast and harmony. Hunt defines that "two colors are complementary when it is possible to reproduce the tristimulus values of a specified achromatic stimulus by an additive mixture of these two stimuli."
That is, when two colored lights can be mixed to match a specified white light, the colors of those two lights are complementary. This definition, does not constrain what version of white will be specified. In the nineteenth century, the scientists Grassmann and Helmholtz did experiments in which they concluded that finding a good complement for spectral yellow was difficult, but that the result was indigo, that is, a wavelength that today's color scientists would call violet or purple. Helmholtz says "indigo blue" are complements. Grassmann reconstructs Newton's category boundaries in terms of wavelengths and says "This indigo therefore falls within the limits of color between which, according to Helmholtz, the complementary colors of yellow lie."Newton's own color circle has yellow directly opposite the boundary between indigo and violet. These results, that the complement of yellow is a wavelength shorter than 450 nm, are derivable from the modern CIE 1931 system of colorimetry if it is assumed that the yellow is about 580 nm or shorter wavelength, the specified white is the color of a blackbody radiator of temperature 2800 K or lower.
More with a daylight-colored or around 5000 to 6000 K white, the complement of yellow will be in the blue wavelength range, the standard modern answer for the complement of yellow. Because of the characteristics of paint pigments and use of different color wheels, painters traditionally regard the complement of yellow as the color indigo or blue-violet. Lasers emitting in the yellow part of the spectrum are less common and more expensive than most other colors. In commercial products diode pumped. An infrared laser diode at 808 nm is used to pump a crystal of neodymium-doped yttrium vanadium oxide or neodymium-doped yttrium aluminium garnet and induces it to emit at
Red harvester ant
Pogonomyrmex barbatus is a species of harvester ant from the genus Pogonomyrmex. Its common names include red harvester ant; these large ants are native to the Southwestern United States. Nests are made underground in exposed areas, their diets consist of seeds, they participate in myrmecochory, an ant-plant interaction through which the ants gain nutrients and the plants benefit through seed dispersal. Red harvester ants are mistaken for fire ants, but are not related to any fire ant species, native or introduced. Red harvester ant nests are characterized by a lack of plant growth and small pebbles surrounding the entrance to the tunnel, which descends at a pronounced angle. Hulls of seeds may be found scattered around the nest. In grassland areas, such as ranches, the lack of plant life makes red harvester ant colonies easy to spot, where they are plentiful, they may make serious inroads into the grazing available to livestock; the mounds are flat and broad, 0 to 100 mm high, 300 to 1,200 mm in diameter.
Larger denuded areas have been reported, on the order of 10 m2. Three to eight trails lead away from the mound, like "arms"; these trails are used by ants to bring food back to the mound. "Scout" ants are the first ones out of the mound every morning. They seek food, mark their path as they return to the mound to alert the worker ants; the worker ants follow the scent collect the food. Other worker ants clean and tend to the mound, the queen, the brood. All the ants in the colonies are females apart from the winged males produced in the breeding season; the reproductive unit of ant populations is the colony. A single virgin queen first mates with several males at a reproductive aggregation site formed by male harvester ants, she flies to a new site to produce an offspring colony. The main food source for red harvester ants consists of seeds, which they hoard in great numbers; the food is first ground to a bread-like consistency using the ants' large mandibles, is stored in a granary, assuring the colony access to food year-round.
Seed collection on behalf of the red harvester ants benefits their ecosystem through the process of myrmecochory, in which ants aid in the dispersal of seeds while foraging for food. Both plants and ants benefit from this relationship: the plants increase their dispersal range and density, while the ants benefit from acquiring nutrients and ensuring a more secure food supply in future harvests; this is understood as a mutualistic interaction. Dead insects are collected during foraging. Much research has been done on the foraging behavior of the red harvester ant. Three types of workers are most involved in the foraging process: nest patrollers, trail patrollers, foragers. On a given day, nest patrollers emerge first from the nest to assess the safety and profitability of foraging; the colony gets the majority of its water from the metabolism of the fats in seeds. If food is scarce, or if it is a hot day, the energy and water benefits of foraging may be outweighed by its energy and water costs.
In this case, the colony may be forced to rely on its extensive food stores. Seeds may be stored in the nest for months or several years; the colony is able to communicate through momentary antennal contact involving the transfer of cuticular hydrocarbons. Other visual and olfactory cues may be involved. Based on the nest patrollers’ reports, trail patrollers may leave the nest to determine the best possible foraging direction; this decision is based upon various economic factors such as food availability and neighboring nests’ foraging behavior. As both types of patrollers return, foragers assess their rates of return to decide whether to leave the nest to find food. In an experiment involving patroller mimics, a return rate of one patroller every 10 seconds stimulated the highest level of foraging activity; this return rate indicates high availability of food and good foraging conditions, therefore a favorable cost-benefit ratio for the foragers exists. If the patroller return rate is too high, it may be a warning of danger, such as the sighting of a predatory lizard.
A lower return rate could indicate lack of available food, or heavy competition Ant foraging is guided by chemical signals that lead the ants up to 50–60 m from the nest at times. Once an ant has decided to forage, it will always continue until it has found food to take back to the nest. Therefore, forager return rate is a good indicator of food availability. Logically, overall foraging activity is influenced by the rate of returning foragers; when food is plentiful, foragers find it and return to the nest. Foragers still in the nest interpret this to mean food searches will be profitable: low energy input with a high chance of a seed reward. Foraging activity is increased. A decline in food availability, indicated by a decrease in forager return rate, causes the colony to decrease its foraging activity; the ability for a colony to regulate its foraging behavior is quite important since their food source is variable and scattered. This regulatory ability is variable in itself, influenced by food availability, current need to eat, colony health.
Colonies are more to adapt to varying forager return rates when the rate of foraging is high, which may be because variances are harder to detect during low rates. Overall, the red harvester ant demonstrates a remarkable ability in social cognition, cost-benefit analysis, behavioral economics. Harvester ant pop
The egg is the organic vessel containing the zygote in which an embryo develops until it can survive on its own. An egg results from fertilization of an egg cell. Most arthropods and mollusks lay eggs, although some, such as scorpions do not. Reptile eggs, bird eggs, monotreme eggs are laid out of water, are surrounded by a protective shell, either flexible or inflexible. Eggs laid on land or in nests are kept within a warm and favorable temperature range while the embryo grows; when the embryo is adequately developed it hatches, i.e. breaks out of the egg's shell. Some embryos have a temporary egg tooth they use to pip, or break the eggshell or covering; the largest recorded egg is from a whale shark, was 30 cm × 14 cm × 9 cm in size. Whale shark eggs hatch within the mother. At 1.5 kg and up to 17.8 cm × 14 cm, the ostrich egg is the largest egg of any living bird, though the extinct elephant bird and some dinosaurs laid larger eggs. The bee hummingbird produces the smallest known bird egg; some eggs laid by reptiles and most fish, amphibians and other invertebrates can be smaller.
Reproductive structures similar to the egg in other kingdoms are termed "spores," or in spermatophytes "seeds," or in gametophytes "egg cells". Several major groups of animals have distinguishable eggs; the most common reproductive strategy for fish is known as oviparity, in which the female lays undeveloped eggs that are externally fertilized by a male. Large numbers of eggs are laid at one time and the eggs are left to develop without parental care; when the larvae hatch from the egg, they carry the remains of the yolk in a yolk sac which continues to nourish the larvae for a few days as they learn how to swim. Once the yolk is consumed, there is a critical point after which they must learn how to hunt and feed or they will die. A few fish, notably the rays and most sharks use ovoviviparity in which the eggs are fertilized and develop internally; however the larvae still grow inside the egg consuming the egg's yolk and without any direct nourishment from the mother. The mother gives birth to mature young.
In certain instances, the physically most developed offspring will devour its smaller siblings for further nutrition while still within the mother's body. This is known as intrauterine cannibalism. In certain scenarios, some fish such as the hammerhead shark and reef shark are viviparous, with the egg being fertilized and developed internally, but with the mother providing direct nourishment; the eggs of fish and amphibians are jellylike. Cartilagenous fish eggs are fertilized internally and exhibit a wide variety of both internal and external embryonic development. Most fish species spawn eggs that are fertilized externally with the male inseminating the eggs after the female lays them; these eggs would dry out in the air. Air-breathing amphibians lay their eggs in water, or in protective foam as with the Coast foam-nest treefrog, Chiromantis xerampelina. Bird eggs are incubated for a time that varies according to the species. Average clutch sizes range from one to about 17; some birds lay eggs when not fertilized.
The default color of vertebrate eggs is the white of the calcium carbonate from which the shells are made, but some birds passerines, produce colored eggs. The pigment biliverdin and its zinc chelate give a green or blue ground color, protoporphyrin produces reds and browns as a ground color or as spotting. Non-passerines have white eggs, except in some ground-nesting groups such as the Charadriiformes and nightjars, where camouflage is necessary, some parasitic cuckoos which have to match the passerine host's egg. Most passerines, in contrast, lay colored eggs if there is no need of cryptic colors; however some have suggested that the protoporphyrin markings on passerine eggs act to reduce brittleness by acting as a solid state lubricant. If there is insufficient calcium available in the local soil, the egg shell may be thin in a circle around the broad end. Protoporphyrin speckling compensates for this, increases inversely to the amount of calcium in the soil. For the same reason eggs in a clutch are more spotted than early ones as the female's store of calcium is depleted.
The color of individual eggs is genetically influenced, appears to be inherited through the mother only, suggesting that the gene responsible for pigmentation is on the sex determining W chromosome. It used to be thought that color was applied to the shell before laying, but this research shows that coloration is an integral part of the development of the shell, with the same protein responsible for depositing calcium carbonate, or protoporphyrins when there is a lack of that mineral. In species such as the common guillemot, which nest in large groups, each female's eggs have different markings, making it easier for females to identify their own eggs on the crowded cliff ledges on which they breed. Bird eggshells are diverse. For example: cormorant eggs are rough and chalky tinamou eggs are shiny duck eggs are oily and waterproof cassowary eggs are pittedTiny pores in bird eggshells allow the embryo to breathe; the domestic
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. While these definitions may seem adequate, when looked at more they represent problematic species concepts. For example, the boundaries between related species become unclear with hybridisation, in a species complex of hundreds of similar microspecies, in a ring species. Among organisms that reproduce only asexually, the concept of a reproductive species breaks down, each clone is a microspecies. All species are given a two-part name, a "binomial"; the first part of a binomial is the genus.
The second part is called the specific epithet. For example, Boa constrictor is one of four species of the genus Boa. None of these is satisfactory definitions, but scientists and conservationists need a species definition which allows them to work, regardless of the theoretical difficulties. If species were fixed and distinct from one another, there would be no problem, but evolutionary processes cause species to change continually, to grade into one another. Species were seen from the time of Aristotle until the 18th century as fixed kinds that could be arranged in a hierarchy, the great chain of being. In the 19th century, biologists grasped. Charles Darwin's 1859 book The Origin of Species explained how species could arise by natural selection; that understanding was extended in the 20th century through genetics and population ecology. Genetic variability arises from mutations and recombination, while organisms themselves are mobile, leading to geographical isolation and genetic drift with varying selection pressures.
Genes can sometimes be exchanged between species by horizontal gene transfer. Viruses are a special case, driven by a balance of mutation and selection, can be treated as quasispecies. Biologists and taxonomists have made many attempts to define species, beginning from morphology and moving towards genetics. Early taxonomists such as Linnaeus had no option but to describe what they saw: this was formalised as the typological or morphological species concept. Ernst Mayr emphasised reproductive isolation, but this, like other species concepts, is hard or impossible to test. Biologists have tried to refine Mayr's definition with the recognition and cohesion concepts, among others. Many of the concepts are quite similar or overlap, so they are not easy to count: the biologist R. L. Mayden recorded about 24 concepts, the philosopher of science John Wilkins counted 26. Wilkins further grouped the species concepts into seven basic kinds of concepts: agamospecies for asexual organisms biospecies for reproductively isolated sexual organisms ecospecies based on ecological niches evolutionary species based on lineage genetic species based on gene pool morphospecies based on form or phenotype and taxonomic species, a species as determined by a taxonomist.
A typological species is a group of organisms in which individuals conform to certain fixed properties, so that pre-literate people recognise the same taxon as do modern taxonomists. The clusters of variations or phenotypes within specimens would differentiate the species; this method was used as a "classical" method of determining species, such as with Linnaeus early in evolutionary theory. However, different phenotypes are not different species. Species named in this manner are called morphospecies. In the 1970s, Robert R. Sokal, Theodore J. Crovello and Peter Sneath proposed a variation on this, a phenetic species, defined as a set of organisms with a similar phenotype to each other, but a different phenotype from other sets of organisms, it differs from the morphological species concept in including a numerical measure of distance or similarity to cluster entities based on multivariate comparisons of a reasonably large number of phenotypic traits. A mate-recognition species is a group of sexually reproducing organisms that recognize one another as potential mates.
Expanding on this to allow for post-mating isolation, a cohesion species is the most inclusive population of individuals having the potential for phenotypic cohesion through intrinsic cohesion mechanisms. A further development of the recognition concept is provided by the biosemiotic concept of species. In microbiology, genes can move even between distantly related bacteria extending to the whole bacterial domain; as a rule of thumb, microbiologists have assumed that kinds of Bacteria or Archaea with 16S ribosomal RNA gene sequences more similar than 97% to each other need to be checked by DNA-DNA hybridisation to decide if they belong to the same species or not. This concept was narrowed in 2006 to a similarity of 98.7%. DNA-DNA hybri
Horned lizards known as horny toads or horntoads, are a genus of North American lizards and the type genus of the family Phrynosomatidae. The common names refer directly to their flattened, rounded body and blunt snout; the genus name Phrynosoma means "toad-bodied". In common with large true frogs and toads, horned lizards tend to move sluggishly, making them easy to catch, they are adapted to semi-arid areas. The spines on the lizard's back and sides are made from modified reptile scales which prevent the water loss through the skin, whereas the horns on the head are true horns. Of the 22 species of horned lizards, 15 are native to the United States; the largest-bodied and most distributed of the US species is the Texas horned lizard. Horned lizards use a wide variety of means to avoid predation, their coloration serves as camouflage. When threatened, their first defense is to remain still to avoid detection. If approached too they run in short bursts and stop abruptly to confuse the predator's visual acuity.
If this fails, they puff up their bodies to cause them to appear more horned and larger, so that they are more difficult to swallow. At least eight species are able to squirt an aimed stream of blood from the corners of the eyes for a distance of up to 5 feet, they do this by restricting the blood flow leaving the head, thereby increasing blood pressure and rupturing tiny vessels around the eyelids. The blood not only confuses predators, but tastes foul to canine and feline predators, it appears to have no effect against predatory birds. Only three related species are known to be unable to squirt blood. While previous thought held that compounds were added to the blood from glands in the ocular sinus cavity, current research has shown that the chemical compounds that make up the defense are in the circulating blood, it is possible. The blood-squirting mechanism increases survival after contact with canine predators. Ocular autohemorrhaging has been documented in other lizards, which suggests blood-squirting could have evolved from a less extreme defense in the ancestral branch of the genus.
Recent phylogenic research supports this claim, so it appears as though the species incapable of squirting blood have lost the adaptation for reasons yet unstudied. To avoid being picked up by the head or neck, a horned lizard ducks or elevates its head and orients its cranial horns straight up, or back. If a predator tries to take it by the body, the lizard drives that side of its body down into the ground so the predator cannot get its lower jaw underneath. A University of Texas publication notes that horned lizard populations continue to disappear throughout the southwest despite protective legislation; the Texas horned lizard has disappeared from half of its geographic range. Population declines are attributed to loss of habitat, human eradication of the ant populations upon which the lizards prey, displacement of native ant populations by invading fire ants, predation by domestic dogs and cats. In 2014, the Center for Biological Diversity in Tucson, Arizona petitioned the Oklahoma Department of Wildlife Conservation to have the Texas horned lizard put on the endangered species list due to the massive declines of its population in Oklahoma, where it was once plentiful.
The Center said it may seek protection for the animal on a Federal level. The following 22 species are recognized as being valid, three species of which have recognized subspecies. Giant horned lizard, Phrynosoma asio Cope, 1864 Phrynosoma bauri Montanucci, 2015 Phrynosoma blainvillii Gray, 1839 Short-tailed horned lizard, Phrynosoma braconnieri A. H. A. Duméril, 1870 Phrynosoma brevirostris Cedros Island horned lizard, Phrynosoma cerroense Stejneger, 1893 Texas horned lizard, Phrynosoma cornutum Coast horned lizard, Phrynosoma coronatum Cape horned lizard, P. c. coronatum California horned lizard, P. c. frontale Van Denburgh, 1894 Central peninsular horned lizard, P. c. jamesi Schmidt, 1922Phrynosoma diminutum Montanucci, 2015 Ditmars' horned lizard or rock horned lizard, Phrynosoma ditmarsi Stejneger, 1906 Pygmy short-horned lizard, Phrynosoma douglasii Phrynosoma goodei Stejneger, 1893 Greater short-horned lizard, Phrynosoma hernandesi Girard, 1858 Flat-tail horned lizard, Phrynosoma mcallii Roundtail horned lizard, Phrynosoma modestum Girard, 1852 Mexican Plateau horned lizard or Chihuahua Desert horned lizard, Phrynosoma orbiculare P. o. bradti Horowitz, 1955 P. o. cortezii P. o. dugesii P. o. orbiculare P. o. orientale Horowitz, 1955Phrynosoma ornatissimum Desert horned lizard, Phrynosoma platyrhinos Girard, 1852Southern desert horned lizard, P. p. calidiarum Northern desert horned lizard, P. p. platyrhinos Girard, 1852Phrynosoma sherbrookei Nieto-Montes de Oca et al. 2014 Regal horned lizard, Phrynosoma solare Gray, 1845 Mexican horned lizard, Phrynosoma taurus Dugès, 1873 Gulf Coast
Arizona is a state in the southwestern region of the United States. It is part of the Western and the Mountain states, it is the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona shares the Four Corners region with Utah and New Mexico. Arizona is the 48th state and last of the contiguous states to be admitted to the Union, achieving statehood on February 14, 1912, coinciding with Valentine's Day. Part of the territory of Alta California in New Spain, it became part of independent Mexico in 1821. After being defeated in the Mexican–American War, Mexico ceded much of this territory to the United States in 1848; the southernmost portion of the state was acquired in 1853 through the Gadsden Purchase. Southern Arizona is known for its desert climate, with hot summers and mild winters. Northern Arizona features forests of pine, Douglas fir, spruce trees. There are ski resorts in the areas of Flagstaff and Tucson. In addition to the Grand Canyon National Park, there are several national forests, national parks, national monuments.
About one-quarter of the state is made up of Indian reservations that serve as the home of 27 federally recognized Native American tribes, including the Navajo Nation, the largest in the state and the United States, with more than 300,000 citizens. Although federal law gave all Native Americans the right to vote in 1924, Arizona excluded those living on reservations in the state from voting until the state Supreme Court ruled in favor of Native American plaintiffs in Trujillo v. Garley; the state's name appears to originate from an earlier Spanish name, derived from the O'odham name alĭ ṣonak, meaning "small spring", which applied only to an area near the silver mining camp of Planchas de Plata, Sonora. To the European settlers, their pronunciation sounded like "Arissona"; the area is still known as alĭ ṣonak in the O'odham language. Another possible origin is the Basque phrase haritz ona, as there were numerous Basque sheepherders in the area. A native Mexican of Basque heritage established the ranchería of Arizona between 1734 and 1736 in the current Mexican state of Sonora, which became notable after a significant discovery of silver there, c.
1737. There is a misconception. For thousands of years before the modern era, Arizona was home to numerous Native American tribes. Hohokam and Ancestral Puebloan cultures were among the many that flourished throughout the state. Many of their pueblos, cliffside dwellings, rock paintings and other prehistoric treasures have survived, attracting thousands of tourists each year; the first European contact by native peoples was with Marcos de Niza, a Spanish Franciscan, in 1539. He explored parts of the present state and made contact with native inhabitants the Sobaipuri; the expedition of Spanish explorer Coronado entered the area in 1540–1542 during its search for Cíbola. Few Spanish settlers migrated to Arizona. One of the first settlers in Arizona was José Romo de Vivar. Father Kino was the next European in the region. A member of the Society of Jesus, he led the development of a chain of missions in the region, he converted many of the Indians to Christianity in the Pimería Alta in the 1690s and early 18th century.
Spain founded presidios at Tubac in 1752 and Tucson in 1775. When Mexico achieved its independence from the Kingdom of Spain and its Spanish Empire in 1821, what is now Arizona became part of its Territory of Nueva California known as Alta California. Descendants of ethnic Spanish and mestizo settlers from the colonial years still lived in the area at the time of the arrival of European-American migrants from the United States. During the Mexican–American War, the U. S. Army occupied the national capital of Mexico City and pursued its claim to much of northern Mexico, including what became Arizona Territory in 1863 and the State of Arizona in 1912; the Treaty of Guadalupe Hidalgo specified that, in addition to language and cultural rights of the existing inhabitants of former Mexican citizens being considered as inviolable, the sum of US$15 million dollars in compensation be paid to the Republic of Mexico. In 1853, the U. S. acquired the land south below the Gila River from Mexico in the Gadsden Purchase along the southern border area as encompassing the best future southern route for a transcontinental railway.
What is now known as the state of Arizona was administered by the United States government as part of the Territory of New Mexico until the southern part of that region seceded from the Union to form the Territory of Arizona. This newly established territory was formally organized by the Confederate States government on Saturday, January 18, 1862, when President Jefferson Davis approved and signed An Act to Organize the Territory of Arizona, marking the first official use of the name "Territory of Arizona"; the Southern territory supplied the Confederate government with men and equipment. Formed in 1862, Arizona scout companies served with the Confederate States Army duri