1.
Conservation status
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The conservation status of a group of organisms indicates whether the group still exists and how likely the group is to become extinct in the near future. Various systems of conservation status exist and are in use at international, multi-country, the IUCN Red List of Threatened Species is the best known worldwide conservation status listing and ranking system. Also included are species that have gone extinct since 500 AD, when discussing the IUCN Red List, the official term threatened is a grouping of three categories, critically endangered, endangered, and vulnerable. Widespread and abundant taxa are included in this category, Data deficient – Not enough data to make an assessment of its risk of extinction Not evaluated – Has not yet been evaluated against the criteria. The Convention on International Trade in Endangered Species of Wild Fauna and Flora aims to ensure that trade in specimens of wild animals. Many countries require CITES permits when importing plants and animals listed on CITES, in the European Union, the Birds and Habitats Directives are the legal instruments that evaluate the conservation status within the EU of species and habitats. NatureServe conservation status focuses on Latin America, United States, Canada, and it has been developed by scientists from NatureServe, The Nature Conservancy, and the network of natural heritage programs and data centers. It is increasingly integrated with the IUCN Red List system and its categories for species include, presumed extinct, possibly extinct, critically imperiled, imperiled, vulnerable, apparently secure, and secure. The system also allows ambiguous or uncertain ranks including inexact numeric ranks, NatureServe adds a qualifier for captive or cultivated only, which has a similar meaning to the IUCN Red List extinct in the wild status. The Red Data Book of the Russian Federation is used within the Russian Federation, in Australia, the Environment Protection and Biodiversity Conservation Act 1999 describes lists of threatened species, ecological communities and threatening processes. The categories resemble those of the 1994 IUCN Red List Categories & Criteria, prior to the EPBC Act, a simpler classification system was used by the Endangered Species Protection Act 1992. Some state and territory governments also have their own systems for conservation status, in Belgium, the Flemish Research Institute for Nature and Forest publishes an online set of more than 150 nature indicators in Dutch. In Canada, the Committee on the Status of Endangered Wildlife in Canada is a group of experts that assesses and designates which wild species are in danger of disappearing from Canada. Under the Species at Risk Act, it is up to the federal government, in China, the State, provinces and some counties have determined their key protected wildlife species. There is the China red data book, in Finland, a large number of species are protected under the Nature Conservation Act, and through the EU Habitats Directive and EU Birds Directive. In Germany, the Federal Agency for Nature Conservation publishes red lists of endangered species, india has the Wild Life Protection Act,1972, Amended 2003 and the Biological Diversity Act,2002. In Japan, the Ministry of Environment publishes a Threatened Wildlife of Japan Red Data Book, in the Netherlands, the Dutch Ministry of Agriculture, Nature and Food Quality publishes a list of threatened species, and conservation is enforced by the Nature Conservation Act 1998. Species are also protected through the Wild Birds and Habitats Directives, in New Zealand, the Department of Conservation publishes the New Zealand Threat Classification System lists
2.
Endangered species
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An endangered species is a species which has been categorized as likely to become extinct. In 2012, the IUCN Red List featured 3079 animal and 2655 plant species as endangered worldwide, the figures for 1998 were, respectively,1102 and 1197. Many nations have laws that protect conservation-reliant species, for example, population numbers, trends and species conservation status can be found in the lists of organisms by population. The conservation status of a species indicates the likelihood that it will become extinct, the IUCN Red List of Threatened Species is the best-known worldwide conservation status listing and ranking system. Over 40% of the species are estimated to be at risk of extinction. Internationally,199 countries have signed an accord to create Biodiversity Action Plans that will protect endangered, in the United States, such plans are usually called Species Recovery Plans. Those species of Near Threatened and Least Concern status have been assessed and found to have relatively robust and healthy populations, though these may be in decline. The IUCN categories, with examples of animals classified by them, include, Extinct Extinct in the wild Captive individuals survive, critically endangered Faces an extremely high risk of extinction in the immediate future. Endangered Faces a high risk of extinction in the near future, vulnerable Faces a high risk of endangerment in the medium term. Near-threatened May be considered threatened in the near future, Least concern No immediate threat to species survival. A population size reduction of ≥ 50%, projected or suspected to be met within the next 10 years or three generations, whichever is the longer, based on any of to under A1. E) Quantitative analysis showing the probability of extinction in the wild is at least 20% within 20 years or five generations, there is data from the United States that shows a correlation between human populations and threatened and endangered species. Under the Endangered Species Act in the United States, species may be listed as endangered or threatened, the Salt Creek tiger beetle is an example of an endangered subspecies protected under the ESA. Some endangered species laws are controversial, also lobbying from hunters and various industries like the petroleum industry, construction industry, and logging, has been an obstacle in establishing endangered species laws. The Bush administration lifted a policy that required federal officials to consult an expert before taking actions that could damage endangered species. Under the Obama administration, this policy has been reinstated, being listed as an endangered species can have negative effect since it could make a species more desirable for collectors and poachers. This effect is potentially reducible, such as in China where commercially farmed turtles may be reducing some of the pressure to poach endangered species. Another problem with the species is its effect of inciting the use of the shoot, shovel
3.
Endangered Species Act of 1973
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The U. S. Supreme Court found that the plain intent of Congress in enacting the ESA was to halt and reverse the trend toward species extinction, whatever the cost. The Act is administered by two agencies, the United States Fish and Wildlife Service and the National Oceanic and Atmospheric Administration. Experimental, nonessential populations of endangered species are treated as threatened species on land, for consultation purposes. The near-extinction of the bison and the disappearance of the passenger pigeon helped drive the call for wildlife conservation starting in the 1900s, the public was introduced to a new concept, extinction. Market hunting for the trade and for the table was one aspect of the problem. The early naturalists also killed birds and other wildlife for study, personal curio collections, while habitat losses continued as communities and farmland grew, the widespread use of pesticides and the introduction of non-native species also affected wildlife. One species in particular received widespread attention—the whooping crane, the species historical range extended from central Canada South to Mexico, and from Utah to the Atlantic coast. It would be eight years before the first national law regulating wildlife commerce was signed. The whooping crane population by 1941 was estimated at about only 16 birds still in the wild, the Lacey Act of 1900 was the first federal law that regulated commercial animal markets. It prohibited interstate commerce of animals killed in violation of state game laws, other legislation followed, including the Migratory Bird Conservation Act of 1929, a 1937 treaty prohibiting the hunting of right and gray whales, and the Bald Eagle Protection Act of 1940. These later laws had a low cost to society–the species were relatively little opposition was raised. Whereas the Lacey Act dealt with game management and market commerce species. The predecessor of the ESA was the Endangered Species Preservation Act of 1966, passed by Congress, this act permitted the listing of native U. S. animal species as endangered and for limited protections upon those animals. It also directed federal agencies to preserve habitat on their lands. The Act also consolidated and even expanded authority for the Secretary of the Interior to manage, other public agencies were encouraged, but not required, to protect species. The act did not address the commerce in endangered species and parts, in March,1967 the first list of endangered species was issued under the act. It included 14 mammals,36 birds,6 reptiles and amphibians and 22 fish and it included only vertebrates because the Department of Interiors definition of fish and wildlife was limited to vertebrates. However, with time, researchers noticed that the animals on the species list still were not getting enough protection
4.
Taxonomy (biology)
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Taxonomy is the science of defining groups of biological organisms on the basis of shared characteristics and giving names to those groups. The exact definition of taxonomy varies from source to source, but the core of the remains, the conception, naming. There is some disagreement as to whether biological nomenclature is considered a part of taxonomy, the broadest meaning of taxonomy is used here. The word taxonomy was introduced in 1813 by Candolle, in his Théorie élémentaire de la botanique, the term alpha taxonomy is primarily used today to refer to the discipline of finding, describing, and naming taxa, particularly species. In earlier literature, the term had a different meaning, referring to morphological taxonomy, ideals can, it may be said, never be completely realized. They have, however, a value of acting as permanent stimulants. Some of us please ourselves by thinking we are now groping in a beta taxonomy, turrill thus explicitly excludes from alpha taxonomy various areas of study that he includes within taxonomy as a whole, such as ecology, physiology, genetics, and cytology. He further excludes phylogenetic reconstruction from alpha taxonomy, thus, Ernst Mayr in 1968 defined beta taxonomy as the classification of ranks higher than species. This activity is what the term denotes, it is also referred to as beta taxonomy. How species should be defined in a group of organisms gives rise to practical and theoretical problems that are referred to as the species problem. The scientific work of deciding how to define species has been called microtaxonomy, by extension, macrotaxonomy is the study of groups at higher taxonomic ranks, from subgenus and above only, than species. While some descriptions of taxonomic history attempt to date taxonomy to ancient civilizations, earlier works were primarily descriptive, and focused on plants that were useful in agriculture or medicine. There are a number of stages in scientific thinking. Early taxonomy was based on criteria, the so-called artificial systems. Later came systems based on a complete consideration of the characteristics of taxa, referred to as natural systems, such as those of de Jussieu, de Candolle and Bentham. The publication of Charles Darwins Origin of Species led to new ways of thinking about classification based on evolutionary relationships and this was the concept of phyletic systems, from 1883 onwards. This approach was typified by those of Eichler and Engler, the advent of molecular genetics and statistical methodology allowed the creation of the modern era of phylogenetic systems based on cladistics, rather than morphology alone. Taxonomy has been called the worlds oldest profession, and naming and classifying our surroundings has likely been taking place as long as mankind has been able to communicate
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Animal
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Animals are multicellular, eukaryotic organisms of the kingdom Animalia. The animal kingdom emerged as a clade within Apoikozoa as the group to the choanoflagellates. Animals are motile, meaning they can move spontaneously and independently at some point in their lives and their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later in their lives. All animals are heterotrophs, they must ingest other organisms or their products for sustenance, most known animal phyla appeared in the fossil record as marine species during the Cambrian explosion, about 542 million years ago. Animals can be divided broadly into vertebrates and invertebrates, vertebrates have a backbone or spine, and amount to less than five percent of all described animal species. They include fish, amphibians, reptiles, birds and mammals, the remaining animals are the invertebrates, which lack a backbone. These include molluscs, arthropods, annelids, nematodes, flatworms, cnidarians, ctenophores, the study of animals is called zoology. The word animal comes from the Latin animalis, meaning having breath, the biological definition of the word refers to all members of the kingdom Animalia, encompassing creatures as diverse as sponges, jellyfish, insects, and humans. Aristotle divided the world between animals and plants, and this was followed by Carl Linnaeus, in the first hierarchical classification. In Linnaeuss original scheme, the animals were one of three kingdoms, divided into the classes of Vermes, Insecta, Pisces, Amphibia, Aves, and Mammalia. Since then the last four have all been subsumed into a single phylum, in 1874, Ernst Haeckel divided the animal kingdom into two subkingdoms, Metazoa and Protozoa. The protozoa were later moved to the kingdom Protista, leaving only the metazoa, thus Metazoa is now considered a synonym of Animalia. Animals have several characteristics that set apart from other living things. Animals are eukaryotic and multicellular, which separates them from bacteria and they are heterotrophic, generally digesting food in an internal chamber, which separates them from plants and algae. They are also distinguished from plants, algae, and fungi by lacking cell walls. All animals are motile, if only at life stages. In most animals, embryos pass through a stage, which is a characteristic exclusive to animals. With a few exceptions, most notably the sponges and Placozoa and these include muscles, which are able to contract and control locomotion, and nerve tissues, which send and process signals
6.
Chordate
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Chordates are deuterostomes, as during the embryo development stage the anus forms before the mouth. They are also bilaterally symmetric coelomates, in the case of vertebrate chordates, the notochord is usually replaced by a vertebral column during development, and they may have body plans organized via segmentation. There are also additional extinct taxa, the Vertebrata are sometimes considered as a subgroup of the clade Craniata, consisting of chordates with a skull, the Craniata and Tunicata compose the clade Olfactores. Of the more than 65,000 living species of chordates, the worlds largest and fastest animals, the blue whale and peregrine falcon respectively, are chordates, as are humans. Fossil chordates are known from at least as early as the Cambrian explosion, Hemichordata, which includes the acorn worms, has been presented as a fourth chordate subphylum, but it now is usually treated as a separate phylum. The Hemichordata, along with the Echinodermata, form the Ambulacraria, the Chordata and Ambulacraria form the superphylum Deuterostomia, composed of the deuterostomes. Attempts to work out the relationships of the chordates have produced several hypotheses. All of the earliest chordate fossils have found in the Early Cambrian Chengjiang fauna. Because the fossil record of early chordates is poor, only molecular phylogenetics offers a prospect of dating their emergence. However, the use of molecular phylogenetics for dating evolutionary transitions is controversial and it has also proved difficult to produce a detailed classification within the living chordates. Attempts to produce family trees shows that many of the traditional classes are paraphyletic. While this has been known since the 19th century, an insistence on only monophyletic taxa has resulted in vertebrate classification being in a state of flux. Although the name Chordata is attributed to William Bateson, it was already in prevalent use by 1880, ernst Haeckel described a taxon comprising tunicates, cephalochordates, and vertebrates in 1866. Though he used the German vernacular form, it is allowed under the ICZN code because of its subsequent latinization, among the vertebrate sub-group of chordates the notochord develops into the spine, and in wholly aquatic species this helps the animal to swim by flexing its tail. In fish and other vertebrates, this develops into the spinal cord, the pharynx is the part of the throat immediately behind the mouth. In fish, the slits are modified to form gills, a muscular tail that extends backwards behind the anus. This is a groove in the wall of the pharynx. In filter-feeding species it produces mucus to gather food particles, which helps in transporting food to the esophagus and it also stores iodine, and may be a precursor of the vertebrate thyroid gland
7.
Mammal
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Mammals are any vertebrates within the class Mammalia, a clade of endothermic amniotes distinguished from reptiles by the possession of a neocortex, hair, three middle ear bones and mammary glands. All female mammals nurse their young with milk, secreted from the mammary glands, Mammals include the largest animals on the planet, the great whales. The basic body type is a quadruped, but some mammals are adapted for life at sea, in the air, in trees. The largest group of mammals, the placentals, have a placenta, Mammals range in size from the 30–40 mm bumblebee bat to the 30-meter blue whale. With the exception of the five species of monotreme, all modern mammals give birth to live young, most mammals, including the six most species-rich orders, belong to the placental group. The largest orders are the rodents, bats and Soricomorpha, the next three biggest orders, depending on the biological classification scheme used, are the Primates, the Cetartiodactyla, and the Carnivora. Living mammals are divided into the Yinotheria and Theriiformes There are around 5450 species of mammal, in some classifications, extant mammals are divided into two subclasses, the Prototheria, that is, the order Monotremata, and the Theria, or the infraclasses Metatheria and Eutheria. The marsupials constitute the group of the Metatheria, and include all living metatherians as well as many extinct ones. Much of the changes reflect the advances of cladistic analysis and molecular genetics, findings from molecular genetics, for example, have prompted adopting new groups, such as the Afrotheria, and abandoning traditional groups, such as the Insectivora. The mammals represent the only living Synapsida, which together with the Sauropsida form the Amniota clade, the early synapsid mammalian ancestors were sphenacodont pelycosaurs, a group that produced the non-mammalian Dimetrodon. At the end of the Carboniferous period, this group diverged from the line that led to todays reptiles. Some mammals are intelligent, with some possessing large brains, self-awareness, Mammals can communicate and vocalize in several different ways, including the production of ultrasound, scent-marking, alarm signals, singing, and echolocation. Mammals can organize themselves into fission-fusion societies, harems, and hierarchies, most mammals are polygynous, but some can be monogamous or polyandrous. They provided, and continue to provide, power for transport and agriculture, as well as commodities such as meat, dairy products, wool. Mammals are hunted or raced for sport, and are used as model organisms in science, Mammals have been depicted in art since Palaeolithic times, and appear in literature, film, mythology, and religion. Defaunation of mammals is primarily driven by anthropogenic factors, such as poaching and habitat destruction, Mammal classification has been through several iterations since Carl Linnaeus initially defined the class. No classification system is accepted, McKenna & Bell and Wilson & Reader provide useful recent compendiums. Though field work gradually made Simpsons classification outdated, it remains the closest thing to a classification of mammals
8.
Even-toed ungulate
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The even-toed ungulates are ungulates whose weight is borne equally by the third and fourth toes. By contrast, odd-toed ungulates, such as horses, bear their weight primarily on their third toe, the aquatic cetaceans evolved from within even-toed ungulates, and therefore modern taxonomic classification sometimes combines Artiodactyla and Cetacea into Cetartiodactyla. The oldest fossils of even-toed ungulates date back to the early Eocene, since these findings almost simultaneously appeared in Europe, Asia, and North America, it is very difficult to accurately determine the origin of artiodactyls. The fossils are classified as belonging to the family Dichobunidae, their best-known and these were small animals, some as small as a hare, with a slim build, lanky legs, and a long tail. The hind legs were longer than the front legs. The early to middle Eocene saw the emergence of the ancestors of most of todays mammals, two formerly widespread, but now extinct, families of even-toed ungulates were Enteledontidae and Anthracotheriidae. Entelodonts existed from the middle Eocene to the early Miocene in Eurasia and they had a stocky body with short legs and a massive head, which was characterized by two humps on the lower jaw bone. Anthracotheres had a large, porcine build, with short legs and this group appeared in the middle Eocene up until the Pliocene, and spread throughout Eurasia, Africa, and North America. Anthracothereres are thought to be the ancestors of hippos, and, likewise, hippopotamuses appeared in the late Miocene and occupied Africa and Asia – they never got to the Americas. The camels were, during parts of the Cenozoic, limited to North America. Among the North American camels were groups like the stocky, short-legged Merycoidodontidae and they first appeared in the late Eocene and developed a great diversity of species in North America. Only in the late Miocene or early Pliocene did they migrate from North America into Eurasia, the North American varieties became extinct around 10,000 years ago. Suina have been around since the Eocene, in the late Eocene or the Oligocene, two families stayed in Eurasia and Africa, the peccaries, which became extinct in the Old World, exist today only in the Americas. South America was settled by even-toed ungulates only in the Pliocene, with only the peccaries, lamoids, and various species of capreoline deer, South America has comparatively fewer artiodactyl families than other continents. The classification of artiodactyls was hotly debated because the ocean-dwelling cetaceans evolved from the land-dwelling even-toed ungulates, some semiaquatic even-toed ungulates are more closely related to the ocean-dwelling cetaceans than to the other even-toed ungulates. This makes the Artiodactyla as traditionally defined an invalid paraphyletic taxon, since it includes animals descended from a common ancestor, phylogenetic classification only recognizes monophyletic taxa, that is, groups that descend from a common ancestor and include all its descendants. To address this problem, the traditional order Artiodactyla and infraorder Cetacea are sometimes subsumed into the more inclusive Cetartiodactyla taxon, an alternative approach is to include both land-land dwelling even toed ungulates and ocean-dwelling cetaceans in a revised Artiodactyla taxon. Order Artiodactyla/Clade CetartiodactylaSuborder Tylopoda Family †Anoplotheriidae, molecular biology involves sequencing an organisms DNA and RNA and comparing the sequence with that of other living beings – the more similar they are, the more closely they are related
9.
Bovidae
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The Bovidae are the biological family of cloven-hoofed, ruminant mammals that includes bison, African buffalo, water buffalo, antelopes, gazelles, sheep, goats, muskoxen, and domestic cattle. A member of family is called a bovid. With 143 extant species and 300 known extinct species, the family Bovidae consists of eight major subfamilies apart from the disputed Peleinae and Pantholopinae, the family evolved 20 million years ago, in the early Miocene. The bovids show great variation in size and pelage colouration, excepting some domesticated forms, all male bovids have two or more horns, and in many species females possess horns, too. Most bovids bear 30 to 32 teeth, social activity and feeding usually peak during dawn and dusk. Bovids typically rest before dawn, during midday, and after dark and they have various methods of social organisation and social behaviour, which are classified into solitary and gregarious behaviour. Bovids use different forms of vocal, olfactory, and tangible communication, most species alternately feed and ruminate throughout the day. While small bovids forage in dense and closed habitat, larger species feed on vegetation in open grasslands. Mature bovids mate at least once a year and smaller species may even mate twice, the greatest diversities of bovids occur in Africa. The maximum concentration of species is in the savannas of eastern Africa, other bovid species also occur in Europe, Asia, and North America. Bovidae includes three of the five domesticated mammals whose use has spread outside their original ranges, namely cattle, sheep, dairy products such as milk, butter, and cheese are manufactured largely from domestic cattle. Bovids also provide leather, meat, and wool, the name Bovidae was given by the British zoologist John Edward Gray in 1821. The word Bovidae is the combination of the prefix bov- and the suffix -idae, the family Bovidae is placed in the order Artiodactyla. It includes 143 extant species, accounting for nearly 55% of the ungulates, molecular studies have supported monophyly in the family Bovidae. The number of subfamilies in Bovidae is disputed, with suggestions of as many as ten, in addition, three extinct subfamilies are known, Hypsodontinae, Oiocerinae and the subfamily Tethytraginae, which contains Tethytragus. In 1992, Alan W. Boodonts have somewhat primitive teeth, resembling those of oxen, a controversy exists about the recognition of Peleinae and Patholopinae, comprising the genera Pelea and Pantholops respectively, as subfamilies. Pantholops, earlier classified in the Antilopinae, was placed in its own subfamily. However, molecular and morphological analysis supports the inclusion of Pantholops in Caprinae, below is a cladogram based on Gatesy et al. and Gentry et al
10.
Caprinae
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Subfamily Caprinae is part of the ruminant family Bovidae, consisting of mostly medium-sized bovids. A member of this subfamily is called a caprine, within this subfamily Caprinae, a prominent tribe Caprini includes sheep, goat, and ibex. Some earlier taxonomies considered Caprinae a separate family called Capridae, but now it is considered a subfamily within the Bovidae family. The European mouflon is thought to be the ancestor of the domestic sheep. Many species have become extinct since the last ice age, probably largely because of human interaction, of the survivors, Five are classified as endangered, Eight as vulnerable, Seven as of concern and needing conservation measures, but at lower risk, and Seven species are secure. Members of the group vary considerably in size, from just over 1 m long for a full-grown grey goral, to almost 2.5 m long for a musk ox, musk oxen in captivity have reached over 650 kg. The resource-defenders are the primitive group, they tend to be smaller in size, dark in colour, males and females fairly alike, have long, tassellated ears, long manes. They tend to be larger, highly social, and rather than mark territory with scent glands, no sharp line divides the groups, but a continuum varies from the serows at one end of the spectrum to sheep, true goats, and musk oxen at the other. The goat-antelope, or caprid, group is known from as early as the Miocene, when members of the group resembled the modern serow in their general body form
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Ovis
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This article refers to the sheep genus. For the species referred to as sheep, see sheep. Ovis is a genus of mammals, part of the subfamily of the ruminant family Bovidae. Its five or more highly sociable species are known as sheep, the domestic sheep is one member of the genus, and is thought to be descended from the wild mouflon of central and southwest Asia. Female sheep are called ewes, males are called rams, the adjective applying to sheep is ovine, and the collective term for sheep is flock or mob. The term herd is also used in this sense. Many specialist terms relating to sheep are used. Sheep are usually stockier than most other bovines, and their horns are usually divergent, Sheep have scent glands on their faces and feet. Communication through the scent glands is not well understood, but is thought to be important for sexual signaling, males can smell females that are fertile and ready to mate, and rams mark their territories by rubbing scent on rocks. Like other ruminants, they have four-chambered stomachs, which play a role in digesting food, they eructate. Domestic sheep are used for their wool, milk, and meat, six species and numerous subspecies of sheep are currently recognised, although some subspecies have also been considered full species. These are the ones, Wild sheep are mostly found in hilly or mountainous habitats. They are fairly small compared to other ungulates, in most species and their diets consist mainly of grasses, as well as other plants and lichens. Like other bovids, their digestive systems enable them to digest and live on low-quality, Sheep conserve water well and can live in fairly dry environments. The bodies of wild sheep are covered by a coat of hair to protect them from cold. This coat contains long, stiff hairs, called kemps, over a short, woolly undercoat and this woolly undercoat has been developed in many domestic sheep breeds into a fleece of long wool, with selection against kemp hairs in these breeds. The fleece covers the body and is used for fibre, Sheep are social animals and live in groups, called flocks. This helps them to avoid predators and stay warm in bad weather by huddling together, flocks of sheep need to keep moving to find new grazing areas and more favourable weather as the seasons change
12.
Bighorn sheep
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The bighorn sheep is a species of sheep native to North America named for its large horns. These horns can weigh up to 14 kilograms, while the sheep themselves weigh up to 140 kg, recent genetic testing indicates three distinct subspecies of Ovis canadensis, one of which is endangered, O. c. sierrae. By 1900, the population had crashed to several thousand, due to diseases introduced through European livestock, divergence from their closest Asian ancestor occurred about 600,000 years ago. In North America, wild sheep diverged into two extant species—Dall sheep, which occupy Alaska and northwestern Canada, and bighorn sheep, which range from southern Canada to Mexico. However, the status of species is questionable given that hybridization has occurred between them in their recent evolutionary history. This subspecies has been extinct since 1925, California bighorn sheep, O. c. californiana, are found from British Columbia south to California and east to North Dakota. The definition of this subspecies has been updated, nelsons bighorn sheep, O. c. nelsoni, the most common desert bighorn sheep, ranges from California through Arizona. Mexican bighorn sheep, O. c. mexicana, range from Arizona and New Mexico south to Sonora and Chihuahua. Peninsular bighorn sheep O. c. cremnobates, occur in the Peninsular Ranges of California and Baja California Rocky Mountain bighorn sheep, weems bighorn sheep, O. c. weemsi, also are found in Baja California. However, starting in 1993, Ramey and colleagues, using DNA testing, have shown this division into seven subspecies is largely illusory, most scientists currently recognize three subspecies of bighorn. Thus the three subspecies of Ovis canadensis, Rocky Mountain bighorn sheep – occupying the U. S. and Canadian Rocky Mountains, Sierra Nevada bighorn sheep – formerly California bighorn sheep, a genetically distinct subspecies that only occurs in the Sierra Nevada in California. However, historic observer records suggest that bighorn sheep may have ranged as far west as the California Coastal Ranges which are contiguous to the Sierra Nevada via the Transverse Ranges. An account of sheep in the vicinity of the Mission San Antonio near Jolon, California. Desert bighorn sheep – occurring throughout the regions of the Southwestern United States. The 2016 genetics study suggested more modest divergence of this desert bighorn sheep into three lineages consistent with the work of Cowan, Nelson, Mexican, and Peninsular. These three lineages occupy desert biomes that vary significantly in climate, suggesting exposure to different selection regimes, Bighorn sheep are named for the large, curved horns borne by the rams. Ewes also have horns, but they are shorter with less curvature and they range in color from light brown to grayish or dark, chocolate brown, with a white rump and lining on the backs of all four legs. Males typically weigh 58–143 kg, are 90–105 cm tall at the shoulder, females are typically 34–91 kg, 75–90 cm tall, and 1. 28–1.58 m long
13.
Clinton Hart Merriam
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Clinton Hart Merriam was an American zoologist, mammalogist, ornithologist, entomologist, ethnographer, and naturalist. Clinton Hart Merriam was born in New York City in 1855 to Clinton Levi Merriam, a U. S. congressman, and Caroline Hart, a judges daughter and graduate of Rutgers Institute. The name Clinton, shared by both father and son, was in honor of New York governor DeWitt Clinton, whom the Merriam family had connections. At the age of fifteen, Merriams father took him to see naturalist Spencer F. Baird at the Smithsonian Institution, beginning in the Wasatch Mountains of Utah, the expedition pushed up through Idaho, Wyoming, and Montana and into the newly established Yellowstone National Park. Merriam returned from the expedition with 313 bird skins and 67 nests with eggs and his report from the trip appears in the Sixth Annual Report of the U. S. Geological Survey of the Territories and marks his first major contribution to the zoological literature. Again Professor Baird stepped in on behalf of Merriam, resolving the issue by recommending that Merriam return to school to prepare for college. Merriam followed Professor Bairds advice and prepared for college by attending Pingry Military School in Elizabeth, New Jersey and Williston Seminary in Easthampton, in 1874, Merriam attended the Sheffield Scientific School of Yale University, where he studied natural history and anatomy. Among the faculty there, Merriam received instruction from prominent figures as Alpheus Hyatt Verrill, Sidney Irving Smith. During this time, Merriam published a paper entitled Ornithological Notes from the South following a trip to Florida with his father. This interest in medicine and surgery led Merriam to move from Yale to the College of Physicians and Surgeons at Columbia University in 1877, in 1878, while at medical school, Merriam helped organize the Linnaean Society of New York and served as its first president. Merriam also was an member of the Nuttall Ornithological Club. Merriam graduated with his M. D. from Columbia University in 1879, from 1879-1885, after earning his M. D. Merriam returned to Locust Grove to practice medicine as a country doctor, becoming quite successful in the endeavor. During this time, Merriam invented scientific and surgical instruments as well as wrote a medical treatise, while practicing medicine, Merriam corresponded with his naturalist colleagues, and continued to build his collection of animal specimens, with a growing interest in mammals. At this time, Merriam became interested in the questions of species distribution. Merriam continued to expand his collection of mammal specimens through correspondence, purchase from local taxidermists. Through these efforts he met Vernon Bailey, a boy from Elk River, Minnesota with an impressive ability to collect species considered rare at the time. Merriam continued to employ Bailey as a collector throughout his career, remotely or as a travel companion, and Bailey would eventually marry Merriams younger sister, Florence, in 1899. By 1884, the year Merriam described his first new species, Atophyrax bendirii, Merriams working collection of mammals numbered over 7,000 specimens, rivaling any public collection at the time
14.
Subspecies
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In biological classification, subspecies is either a taxonomic rank subordinate to species, or a taxonomic unit in that rank. A subspecies cannot be recognized independently, a species will either be recognized as having no subspecies at all or at least two, in zoology, under the International Code of Zoological Nomenclature, the subspecies is the only taxonomic rank below that of species that can receive a name. In botany and mycology, under the International Code of Nomenclature for algae, fungi, in bacteriology and virology, under standard bacterial nomenclature and virus nomenclature, there are recommendations but not strict requirements for recognizing other important infraspecific ranks. A taxonomist decides whether to recognize a subspecies or not, the differences between subspecies are usually less distinct than the differences between species. In zoology, the International Code of Zoological Nomenclature accepts only one rank below that of species, other groupings, infrasubspecific entities do not have names regulated by the ICZN. Such forms have no official ICZN status, though they may be useful in describing altitudinal or geographical clines, pet breeds, transgenic animals, etc. While the scientific name of a species is a binomen, the name of a subspecies is a trinomen - a binomen followed by a subspecific name. A tigers binomen is Panthera tigris, so for a Sumatran tiger the trinomen is, for example, names published before 1992 in the rank of variety are taken to be names of subspecies. In botany, subspecies is one of many ranks below that of species, such as variety, subvariety, form, the subspecific name is preceded by subsp. or ssp. as Schoenoplectus californicus ssp. tatora. A botanical name consists of at most three parts, an infraspecific name includes the species binomial, and one infraspecific epithet, such as subspecies or variety. For example, Motacilla alba alba is the subspecies of the white wagtail. The subspecies name that repeats the name is referred to in botanical nomenclature as the subspecies autonym. When zoologists disagree over whether a population is a subspecies or a full species. A subspecies is a rank below species – the only recognized rank in the zoological code. Botanists and mycologists have the choice of ranks lower than subspecies, such as variety or form, in biological terms, rather than in relation to nomenclature, a polytypic species has two or more subspecies, races, or more generally speaking, populations that need a separate description. These are separate groups that are distinct from one another and do not generally interbreed. These subspecies, races, or populations, can be named as subspecies by zoologists, a monotypic species has no distinct population or races, or rather one race comprising the whole species. A taxonomist would not name a subspecies within such a species, monotypic species can occur in several ways, All members of the species are very similar and cannot be sensibly divided into biologically significant subcategories
15.
Southwestern United States
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The population of the area is around 11 million people, with over half that in Arizona, the most populous cities are Phoenix, El Paso, Las Vegas, Albuquerque, and Tucson. Most of the area was part of the Viceroyalty of New Spain in the Spanish Empire before becoming part of Mexico and it became part of the United States through the Treaty of Guadalupe Hidalgo and the Gadsden Purchase. The deserts dominate the southern and western reaches of the area, the two major rivers of the region are the Colorado River, running in the northern and western areas, and the Rio Grande, running in the south. Formed approximately 8000 years ago, the Chihuahuan Desert is a dry desert. The Chihuahuan Desert spreads across the portion of the region, covering from southeastern Arizona, across southern New Mexico. While it is the second largest desert in the United States, only a third of the desert is within the United States, El Paso is the major city in this desert, with other smaller cities being Las Cruces and Roswell in New Mexico. The Chihuahuan is a rain shadow desert, formed two mountain ranges which block oceanic precipitation from reaching the area. The most prolific plants in this region are agave, yucca and creosote bushes, when people think of the desert southwest, the landscape of the Sonoran Desert is what mostly comes to mind. Rainfall averages between 4–12 inches per year, and the deserts most widely known inhabitant is the saguaro cactus and it is bounded on the northwest by the Mojave Desert, to the north by the Colorado Plateau and to the east by the Arizona Mountains forests and the Chihuahuan Desert. The portion of the Sonora Desert which lies in the Southwestern United States is the most populated area within the region. Six of the top ten major population centers of the region are found within its borders, Phoenix, Tucson, Mesa, Chandler, Glendale, also within its borders are Yuma and Prescott Arizona. The most northwest portion of the American Southwest is covered by the Mojave Desert, bordered on the south by the Sonoran Desert and the east by the Colorado Plateau, its range within the region makes up the southeast tip of Nevada, and the northwestern corner of Arizona. In terms of topography, the Mojave is very similar to the Great Basin Desert, the Mojave is the smallest, driest and hottest desert within the United States. The Mojave gets less than six inches of rain annually, the most prolific vegetation is the tall Joshua tree, which grow as tall as 40 feet, and are thought to live almost 1000 years. Other major vegetation includes the Parry saltbush and the Mojave sage, the Colorado Plateau varies from the large stands of forests in the west, including the largest stand of ponderosa pine trees in the world, to the Mesas to the east. Although not called a desert, the Colorado Plateau is mostly made up of high desert, the Plateau is characterized by a series of plateaus and mesas, interspersed with canyons. The most dramatic example is the Grand Canyon, but that is one of many dramatic vistas included within the Plateau, which includes spectacular lava formations, painted deserts, sand dunes, and badlands. One of the most distinctive features of the Plateau is its longevity, the Plateau can be divided into six sections, three of which fall into the Southwest region
16.
Edward William Nelson
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Edward William Nelson was an American naturalist and ethnologist. He was born in Manchester, New Hampshire, in 1871 together with his family, he became homeless due to the Chicago Fire. In 1877 Nelson joined the U. S. Army Signal Corps, spencer Fullerton Baird was responsible for selecting Signal Officers for the remoter stations, and would choose men with scientific training who were prepared to study the local flora and fauna. Baird sent Nelson to St. Michael, Alaska, Nelson was the naturalist on board the USRC Corwin, which sailed to Wrangel Island in search of the USS Jeanette in 1881. Nelson published his findings in the Report upon Natural History Collections Made in Alaska between the Years 1877–1881 and he also published his ethnological findings in The Eskimo about Bering Strait. After this expedition he was ordered to conduct a survey in Mexico. Nelson continued to work for the Bureau of Biological Survey until 1929, the desert bighorn sheep and Nelsons milksnake were named in his honor. The holotype of the milksnake was collected by Nelson and Edward Alphonso Goldman on July 18,1897 and he worked with Goldman for ten years surveying Mexican terrestrial vertebrates. Nelsons sparrow was named for him. In addition to the above-mentioned Nelsons milk snake, four other reptiles are named in honor of Nelson, Nelsons anole, Nelsons tree lizard, Nelsons spiny lizard and he was the president of the American Society of Mammalogists from 1921 to 1923. He also served as president of the American Ornithologists Union and the Biological Society of Washington, susan A. Kaplan, and Henry B. Inua, spirit world of the Bering Sea Eskimo, published for the National Museum of Natural History by the Smithsonian Institution Press
17.
Mojave Desert
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The Mojave Desert is an arid rain-shadow desert and the driest desert in North America. It is located in the southwestern United States, primarily within southeastern California and southern Nevada, very small areas also extend into Utah and Arizona. The central part of the desert is sparsely populated, while its peripheries support large communities such as Las Vegas, Lancaster, Palmdale, Victorville, the Mojave Desert is bordered by the Great Basin Desert to its north and the Sonoran Desert to its south and east. Topographical boundaries include the Tehachapi Mountains to the west, and the San Gabriel Mountains, the mountain boundaries are distinct because they are outlined by the two largest faults in California – the San Andreas and Garlock faults. The Mojave Desert displays typical basin and range topography and it occupies less than 50,000 sq mi, making it the smallest of the North American deserts. The Mojave Desert is often referred to as the desert, in contrast to the low desert. However, the Mojave Desert is generally lower than the Great Basin Desert to the north, the spelling Mojave originates from the Spanish language while the spelling Mohave comes from modern English. The Mojave Desert receives less than 13 in of rain a year and is generally between 2,000 and 5,000 feet in elevation, zion National Park in Utah lies at the junction of the Mojave, the Great Basin Desert, and the Colorado Plateau. Despite its aridity, the Mojave has long been a center of production, fed by irrigation coming from groundwater. The Mojave is a desert of temperature extremes and two distinct seasons, winter months bring comfortable daytime temperatures, which dip precipitously to around 20 °F on valley floors, and below 0 °F at higher elevations. Storms moving from the Pacific Northwest can bring rain and in places even snow. More often, the shadow created by the Sierra Nevada as well as mountain ranges within the desert such as the Spring Mountains, bring only clouds. By early June, it is rare for another Pacific storm to have a significant impact on the regions weather, summer weather is dominated by heat. Temperatures on valley floors can soar above 120 °F and above 130 °F at the lowest elevations, low humidity, high temperatures, and low pressure, draw in moisture from the Gulf of Mexico creating thunderstorms across the desert southwest known as the North American monsoon. Autumn is generally pleasant, with one to two Pacific storm systems creating regional rain events, october is one of the driest and sunniest months in the Mojave, and temperatures usually remain between 70 °F and 90 °F on the valley floors. After temperature, wind is the most significant weather phenomenon in the Mojave, during the June Gloom, cooler air can be pushed out into the desert from Southern California. In Santa Ana wind events, hot air from the desert blows out into the Los Angeles basin, wind farms in these areas generate power from these winds. The other major factor in the region is elevation
18.
Sonoran Desert
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It is the hottest desert in Mexico. It has an area of 260,000 square kilometers, the western portion of the United States–Mexico border passes through the Sonoran Desert. In phytogeography, the Sonoran Desert is within the Sonoran Floristic Province of the Madrean Region in southwestern North America, the desert contains a variety of unique and endemic plants and animals, such as the saguaro and organ pipe cactus. It is bounded on the west by the Peninsular Ranges, which separate it from the California chaparral and woodlands, to the north in California and northwest Arizona, the Sonoran Desert transitions to the colder-winter, higher-elevation Mojave, Great Basin, and Colorado Plateau deserts. To the east and southeast, the transition to the coniferous Arizona Mountains forests and Sierra Madre. To the south the Sonoran–Sinaloan transition subtropical dry forest is the zone from the Sonoran Desert to the tropical dry forests of the Mexican state of Sinaloa. The deserts sub-regions include the Colorado Desert of southeastern California, many ecologists now consider Shreves Vizcaíno and Magdalena regions, which lie on the western side of the Baja California Peninsula, to be a separate ecoregion, the Baja California Desert. The Pinacate National Park includes the only active Erg dune region in North America, the nearest city to the Reserva de la Biosfera el Pinacate y Gran Desierto de Altar is Puerto Peñasco in the state of Sonora, Mexico. The Sonoran Desert area southeast of Tucson and near the Mexican border is vital habitat for the population of jaguars living within the United States. Many plants not only survive, but thrive in the conditions of the Sonoran Desert. Many have evolved to have specialized adaptations to the desert climate, the Sonoran Deserts biseasonal rainfall pattern results in more plant species than any other desert in the world. The Sonoran Desert includes plant genera and species from the family, palm family, cactus family, legume family. The Sonoran is the place in the world where the famous saguaro cactus grows in the wild. Cholla, beavertail, hedgehog, fishhook, prickly pear, nightblooming cereus, creosote bush and bur sage dominate valley floors. Indigo bush and Mormon tea are other shrubs that may be found, wildflowers of the Sonoran Desert include desert sand verbena, desert sunflower, and evening primroses. Ascending from the valley up bajadas, various such as velvet mesquite, palo verde, desert ironwood, desert willow. Shrubs found at higher elevations include whitethorn acacia, fairy duster, in the desert subdivisions found on Baja California, cardon cactus, elephant tree, and boojum tree occur. The California fan palm is found in the Colorado Desert section of the Sonoran Desert and it is found at spring-fed oases, such as in Anza Borrego Desert State Park, Joshua Tree National Park, and the Kofa National Wildlife Refuge
19.
Anza-Borrego Desert State Park
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Anza-Borrego Desert State Park is a state park located within the Colorado Desert of southern California, United States. The park takes its name from 18th century Spanish explorer Juan Bautista de Anza and borrego, the Spanish word for bighorn sheep. With 600,000 acres that includes one-fifth of San Diego County, ABDSP is the largest state park in California and, after New Yorks Adirondack Park, the second largest in the contiguous United States. The park occupies eastern San Diego County and reaches into Imperial and Riverside counties, ABDSP is around a two-hour drive northeast from San Diego, southeast from Riverside or Irvine, and south from Palm Springs. The park is an anchor in the Mojave and Colorado Deserts Biosphere Reserve, Park information and maps, interpretive events and displays and listening devices for the hearing impaired are all available in the Visitor Center. ABDSP has Wi-Fi access to the Internet in various sections of the park, many visitors approach ABDSP from the east-Coachella Valley side via California County Route S22 and S78. These highways climb from the coast to 2,400 ft above sea level, the great bowl of the surrounding desert is surrounded by mountains, with the Vallecito Mountains to the south and the highest Santa Rosa Mountains to the north. They are in the wilderness area, without paved roads. In January of 2017 Anza-Borrego Desert State Park was named the best state park in California, the habitats of ABDSP are primarily within the Colorado Desert ecosystem of the Sonoran Desert ecoregion. The higher extreme northern and eastern sections in the Peninsular Ranges are in the California montane chaparral, the park features, bajadas and desert washes, rock formations and colorful badlands, vast arid landscapes, and dramatic mountains. The bajadas are predominantly creosote bush-bur sage with creosote bush and the palo verde-cactus shrub ecosystems with the palo verde tree, cacti, in the washes, Colorado/Sonoran microphylla woodlands can be found. These woodlands include such plants as tree, velvet mesquite. ABDSP has natural springs and oases, with the only native palm. Seasonal wildflower displays can be stunning in any plant community association throughout the park, the high-country to the north and east has closed-cone pine forests, manzanitas and oak woodlands. The oases are prolific with all types of fauna, especially for bird-watching, in the reptile class, desert iguanas, chuckwallas, and the red diamond rattlesnakes can be seen — with caution. ===Desert bighorn sheep=== Some areas of ABDSP are habitat for the Peninsular bighorn sheep, few park visitors see them, and the sheep are justly wary. A patient few observers each year see and count this endangered species to study the population, the expanses of ABDSPs eroded badlands also provide a different view into the regions long-vanished tropical past. The inland of southeastern California was not always a desert, paleontology, the study of the fossilized remains of ancient life, is the key to understanding this prehistoric world
20.
Joshua Tree National Park
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Joshua Tree National Park is located in southeastern California. Declared a U. S. National Park in 1994 when the U. S. Congress passed the California Desert Protection Act and it is named for the Joshua trees native to the park. It covers a area of 790,636 acres —an area slightly larger than the state of Rhode Island. A large part of the park, some 429,690 acres, is a wilderness area. The Little San Bernardino Mountains run through the southwest edge of the park, in 1950, the size of the park was reduced by about 265,000 acres to exclude some mining property. The park was elevated to a National Park on 31 October 1994 by the Desert Protection Act, the higher and cooler Mojave Desert is the special habitat of Yucca brevifolia, the Joshua tree for which the park is named. It occurs in patterns from dense forests to distantly spaced specimens, in addition to Joshua tree forests, the western part of the park includes some of the most interesting geologic displays found in Californias deserts. The dominant geologic features of landscape are hills of bare rock. These hills are popular amongst rock climbing and scrambling enthusiasts, the flatland between these hills is sparsely forested with Joshua trees. Together with the piles and Skull Rock, the trees make the landscape otherworldly. Temperatures are most comfortable in the spring and fall, with an average high/low of 85 and 50 °F respectively, winter brings cooler days, around 60 °F, and freezing nights. It occasionally snows at higher elevations, summers are hot, over 100 °F during the day and not cooling much below 75 °F until the early hours of the morning. Joshua trees dominate the open spaces of the park, but in among the outcroppings are piñon pine, California juniper, Quercus turbinella, Quercus john-tuckeri. These communities are under stress, however, as the climate was wetter until the 1930s, with the same hot. These cycles were nothing new, but the vegetation did not prosper when wetter cycles returned. The difference may have been human development, cattle grazing took out some of the natural cover and made it less resistant to the changes. But the bigger problem seems to be invasive species, such as cheatgrass, in drier times, they die back, but do not quickly decompose. This makes wildfires hotter and more destructive, which some of the trees that would have otherwise survived
21.
Death Valley National Park
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Death Valley National Park is a national park in the United States. Straddling the border of California and Nevada, located east of the Sierra Nevada, the park protects the northwest corner of the Mojave Desert and contains a diverse desert environment of salt-flats, sand dunes, badlands, valleys, canyons, and mountains. It is the largest national park in the lower 48 states and has declared an International Biosphere Reserve. Approximately 91% of the park is a wilderness area. It is the hottest, driest and lowest of the parks in the United States. The second-lowest point in the Western Hemisphere is in Badwater Basin, the park is home to many species of plants and animals that have adapted to this harsh desert environment. Some examples include creosote bush, bighorn sheep, coyote, and the Death Valley pupfish, several short-lived boom towns sprang up during the late 19th and early 20th centuries to mine gold and silver. The only long-term profitable ore to be mined was borax, which was transported out of the valley with twenty-mule teams, the valley later became the subject of books, radio programs, television series, and movies. Tourism blossomed in the 1920s, when resorts were built around Stovepipe Wells, Death Valley National Monument was declared in 1933 and the park was substantially expanded and became a national park in 1994. The natural environment of the area has been shaped largely by its geology, the valley itself is actually a graben. The oldest rocks are metamorphosed and at least 1.7 billion years old. Ancient, warm, shallow seas deposited marine sediments until rifting opened the Pacific Ocean, additional sedimentation occurred until a subduction zone formed off the coast. This uplifted the region out of the sea and created a line of volcanoes, later the crust started to pull apart, creating the current Basin and Range landform. Valleys filled with sediment and, during the wet times of glacial periods, with lakes, in 2013, Death Valley National Park was designated as a dark sky park by the International Dark-Sky Association. There are two valleys in the park, Death Valley and Panamint Valley. Both of these valleys were formed within the last few million years, the result of this shearing action is additional extension in the central part of Death Valley which causes a slight widening and more subsidence there. Uplift of surrounding mountain ranges and subsidence of the floor are both occurring. The uplift on the Black Mountains is so fast that the fans there are small
22.
Kofa National Wildlife Refuge
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The Kofa National Wildlife Refuge is located in Arizona in the southwestern United States, northeast of Yuma and southeast of Quartzsite. The refuge, established in 1939 to protect desert bighorn sheep, broad, gently sloping foothills as well as the sharp, needlepoint peaks of the Kofa Mountains are found in the rugged refuge. The small, widely scattered waterholes attract a number of water birds for a desert area. A wide variety of plant life is found throughout the refuge. The name Kofa comes from an area gold mine, the King of Arizona mine. In 1936, the Arizona Boy Scouts mounted a campaign to save the bighorn sheep. He called George F. Miller, then scout executive of the Boy Scout council headquartered in Phoenix, several other prominent Arizonans joined the movement and a save the bighorns poster contest was started in schools throughout the state. Burnham provided prizes and appeared in store windows from one end of Arizona to the other, the contest-winning bighorn emblem was made into neckerchief slides for the 10,000 Boy Scouts, and talks and dramatizations were given at school assemblies and on radio. The National Wildlife Federation, the Izaak Walton League, and the Audubon Society joined the effort, on April 2,1939, Kofa National Wildlife Refuge was officially opened, Burnham gave the dedication speech. The desert bighorn sheep is now the mascot for the Arizona Boy Scouts. The Kofa Game Range, as it was called, was administered jointly by the U. S. Fish and Wildlife Service. On February 5,1975, Kofa was transferred exclusively to the Bureau of Land Management, but in 1976 complete authority was returned to the Department of Fish and Wildlife Services and the Kofa Game Range was renamed the Kofa National Wildlife Refuge. The population of bighorn sheep was recently estimated to be 428. They live mainly in the two ranges that dominate the refuge landscape — the Kofa Mountains and Castle Dome Mountains of northern Yuma County and these mountains are not especially high, but they are extremely rugged and rise sharply from the surrounding desert plains, providing excellent bighorn sheep habitat. In recent years, this herd has provided animals for transplanting throughout Arizona, other notable wildlife species found in the area include the badger, desert tortoise and kit fox. Bird species that occur at Kofa include the dove, American kestrel, northern flicker, Says phoebe, cactus wren, phainopepla. In recent years, the cougar has established a presence in the park. The Kofa Mountain barberry, Berberis harrisoniana, a plant endemic to southwestern Arizona
23.
Cabeza Prieta National Wildlife Refuge
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Cabeza Prieta National Wildlife Refuge is located in southwestern Arizona in the United States, along 56 miles of the Mexico–United States border. Today, it is home to more than 275 different species of animals, CPNWR is the third largest national wildlife refuge in the lower 48 states. Its total area is 860,010 acres, which is greater than that of the state of Rhode Island, the refuge is administered from a small headquarters building, located in Ajo. Spanish for dark head, the name comes from the Cabeza Prieta Mountains in the refuges northwest part. 803,418 acres — amounting to 93% of the area of CPNWR — was preserved in 1990 as the Cabeza Prieta Wilderness. Author Edward Abbey, a frequent visitor, described the refuge as the best desert wilderness left in the United States, there are only three public-use roads in the refuge, El Camino Del Diablo, Christmas Pass Road and Charlie Bell Road. All of these are unpaved, and they are very difficult to travel because of deep mud and sand, sharp rocks, vegetation. Four-wheel drive vehicles are required on El Camino Del Diablo and Christmas Pass Road, Charlie Bell Road can be traversed in a 2-wheel drive vehicle, provided the vehicle has a high clearance. There are no facilities on the refuge, including gasoline, sanitation or potable water, visitors are advised to carry two spare tires and other spare mechanical parts in case of a breakdown. The purpose of this closure is to disturbance to herds containing fawns. CPNWR is located within the Yuma Desert, a section of the Sonoran Desert. Despite the harshness of the environment, the refuge is home to more than 275 different species of animals. Many species of birds are permanent residents of CPNWR, while others migrate through during the spring. Most of the fauna are xerocoles, and they tend to be nocturnal or crepuscular, most active at dawn. Some of the commonly encountered at CPNWR include, In 1936. The Scouts first became interested in the sheep through the efforts of Major Frederick Russell Burnham, Burnham observed that fewer than 150 of these sheep still lived in the Arizona mountains. He called George F. Miller, then scout executive of the boy scout council headquartered in Phoenix, several other prominent Arizonans joined the movement and a Save the Bighorns poster contest was started in schools throughout the state. The contest-winning bighorn emblem was made up into neckerchief slides for the 10,000 Boy Scouts, the National Wildlife Federation, the Izaak Walton League, and the National Audubon Society also joined the effort
24.
Mojave National Preserve
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Mojave National Preserve is a United States National Preserve located in the Mojave Desert of San Bernardino County, California, USA, between Interstate 15 and Interstate 40. The preserve was established October 31,1994 with the passage of the California Desert Protection Act by the US Congress, previously, it was the East Mojave National Scenic Area, under the jurisdiction of the Bureau of Land Management. At 1,600,000 acres, it is the third largest unit of the National Park System in the contiguous United States. Natural features include the Kelso Dunes, the Marl Mountains and the Cima Dome, as well as volcanic formations such as Hole-in-the-Wall, the preserve encloses Providence Mountains State Recreation Area and Mitchell Caverns Natural Preserve, which are both managed by the California Department of Parks and Recreation. Impressive Joshua Tree forests cover parts of the preserve, the Cima Dome and Shadow Valley forests are the largest in the world. The defunct railroad depot and ghost town of Kelso are also found there, the depot is now the visitor center. The preserve is commonly traversed by 4 wheel drive vehicles traveling on the historic Mojave Road, summer temperatures average 90 °F, with highs exceeding 105 °F. Elevations in the Preserve range from 7,929 feet at Clark Mountain to 880 feet near Baker. Annual precipitation varies from 3.37 inches near Baker, to almost 9 inches in the mountains, at least 25% of precipitation comes from summer thunderstorms. Snow is often found in the mountains during the winter, the California Desert Protection Act of 1994 designated a wilderness area within Mojave National Preserve of approximately 695,200 acres. The National Park Service manages the wilderness in accordance with the Wilderness Act, the CDPA, the following climate data is for a higher elevation area in the preserve. See also Climate of the Mojave Desert, Mojave Memorial Cross Official website Photo tour of Mojave National Preserve - from USGS
25.
Population
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A population is the number of all the organisms of the same group or species, which live in a particular geographical area, and have the capability of interbreeding. In sociology, population refers to a collection of humans, Demography is a social science which entails the statistical study of human populations. This article refers mainly to human population, in population genetics a sexual population is a set of organisms in which any pair of members can breed together. This means that they can regularly exchange gametes to produce normally-fertile offspring and this also implies that all members belong to the same species. If the gamodeme is very large, and all gene alleles are uniformly distributed by the gametes within it, however, there may be low frequencies of exchange with these neighbours. This may be viewed as the breaking up of a sexual population into smaller overlapping sexual populations. The overall rise in homozygosity is quantified by the inbreeding coefficient, note that all homozygotes are increased in frequency – both the deleterious and the desirable. The mean phenotype of the collection is lower than that of the panmictic original – which is known as inbreeding depression. It is most important to note, however, that some lines will be superior to the panmictic original, while some will be about the same. The probabilities of each can be estimated from those binomial equations, in plant and animal breeding, procedures have been developed which deliberately utilise the effects of dispersion. It can be shown that dispersion-assisted selection leads to the greatest genetic advance and this is so for both allogamous and autogamous gamodemes. In ecology, the population of a species in a certain area can be estimated using the Lincoln Index. As of todays date, the population is estimated by the United States Census Bureau to be 7.496 billion. The US Census Bureau estimates the 7 billion number was surpassed on 12 March 2012, according to papers published by the United States Census Bureau, the world population hit 6.5 billion on 24 February 2006. The United Nations Population Fund designated 12 October 1999 as the day on which world population reached 6 billion. This was about 12 years after world population reached 5 billion in 1987, the population of countries such as Nigeria, is not even known to the nearest million, so there is a considerable margin of error in such estimates. Researcher Carl Haub calculated that a total of over 100 billion people have probably been born in the last 2000 years, Population growth increased significantly as the Industrial Revolution gathered pace from 1700 onwards. In 2007 the United Nations Population Division projected that the population will likely surpass 10 billion in 2055
26.
European colonization of the Americas
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European colonization of the Americas began as early as the 10th–11th century, when West Norse sailors explored and briefly settled limited areas on the shores of present-day Canada. These Norsemen were Vikings who had discovered and settled Greenland, then sailed up the Arctic region of North America alongside Greenland, according to Icelandic Sagas, violent conflicts with the indigenous population ultimately made the Norse abandon those settlements. Running aground on the part of Hispaniola on December 5,1492, which the Taino people had inhabited since the 7th century. European conquest, large-scale exploration, colonization and industrial development soon followed, Columbus first two voyages reached the Bahamas and various Caribbean islands, including Hispaniola, Puerto Rico and Cuba. In 1497, sailing from Bristol on behalf of England, John Cabot landed on the North American coast, other powers such as France also founded colonies in the Americas, in eastern North America, a number of Caribbean islands, and small coastal parts of South America. Portugal colonized Brazil, tried colonizing the coasts of present-day Canada, the Age of Exploration was the beginning of territorial expansion for several European countries. Eventually, the entire Western Hemisphere came under the control of European governments, leading to profound changes to its landscape, population. In the 19th century alone over 50 million people left Europe for the Americas, Norse journeys to Greenland and Canada are supported by historical and archaeological evidence. It was named a World Heritage site by UNESCO in 1978, Early explorations and conquests were made by the Spanish and the Portuguese immediately following their own final reconquest of Iberia in 1492. Spanish conquistador Hernán Cortés took over the Aztec Kingdom and Francisco Pizarro conquered the Inca Empire, over this same timeframe, Portugal claimed lands in North America and colonized much of eastern South America, naming it Santa Cruz and Brazil. Other European nations soon disputed the terms of the Treaty of Tordesillas, England and France attempted to plant colonies in the Americas in the 16th century, but these failed. England and France succeeded in establishing permanent colonies in the following century, in the 18th century, Denmark–Norway revived its former colonies in Greenland, while the Russian Empire gained a foothold in Alaska. Denmark-Norway would later make claims in the Caribbean, starting in the 1600s. As more nations gained an interest in the colonization of the Americas, colonists often faced the threat of attacks from neighboring colonies, as well as from indigenous tribes and pirates. He was followed by other such as John Cabot, who was sponsored by England. Pedro Álvares Cabral reached Brazil and claimed it for Portugal, amerigo Vespucci, working for Portugal in voyages from 1497 to 1513, established that Columbus had reached a new set of continents. Cartographers still use a Latinized version of his first name, America, in 1513, Vasco Núñez de Balboa crossed the Isthmus of Panama and led the first European expedition to see the Pacific Ocean from the west coast of the New World. In an action with enduring historical import, Balboa claimed the Pacific Ocean and it was 1517 before another expedition, from Cuba, visited Central America, landing on the coast of Yucatán in search of slaves
27.
Conservation biology
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It is an interdisciplinary subject drawing on natural and social sciences, and the practice of natural resource management. The conservation ethic is based on the findings of conservation biology, wilcox and Michael E. Soulé with a group of leading university and zoo researchers and conservationists including Kurt Benirschke, Sir Otto Frankel, Thomas E. Lovejoy, and Jared M. Diamond. The meeting was prompted by the concern over deforestation, disappearing species. Conservation biology and the concept of biological diversity emerged together, helping crystallize the modern era of conservation science, the inherent multidisciplinary basis for conservation biology has led to new subdisciplines including conservation social science, conservation behavior and conservation physiology. It stimulated further development of genetics which Otto Frankel had originated first but is now often considered a subdiscipline as well. The rapid decline of established biological systems around the means that conservation biology is often referred to as a Discipline with a deadline. Conservation biology is tied closely to ecology in researching the ecology of rare or endangered species. Conservation biologists work in the field and office, in government, universities, non-profit organizations, the topics of their research are diverse, because this is an interdisciplinary network with professional alliances in the biological as well as social sciences. Those dedicated to the cause and profession advocate for a response to the current biodiversity crisis based on morals, ethics. Conscious efforts to conserve and protect global biodiversity are a recent phenomenon, natural resource conservation, however, has a history that extends prior to the age of conservation. Resource ethics grew out of necessity through direct relations with nature and this social dilemma with respect to natural resource management is often called the Tragedy of the Commons. From this principle, conservation biologists can trace communal resource based ethics throughout cultures as a solution to communal resource conflict. For example, the Alaskan Tlingit peoples and the Haida of the Pacific Northwest had resource boundaries, rules and these rules were guided by clan elders who knew lifelong details of each river and stream they managed. There are numerous examples in history where cultures have followed rules, rituals, Conservation ethics are also found in early religious and philosophical writings. There are examples in the Tao, Shinto, Hindu, Islamic, in the bible, through Moses, God commanded to let the land rest from cultivation every seventh year. Before the 18th century, however, much of European culture considered it a view to admire nature. Wilderness was denigrated while agricultural development was praised, however, as early as AD680 a wildlife sanctuary was founded on the Farne Islands by St Cuthbert in response to his religious beliefs. Natural history was a preoccupation in the 18th century, with grand expeditions
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Sheep
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The sheep is a quadrupedal, ruminant mammal typically kept as livestock. Like all ruminants, sheep are members of the order Artiodactyla, although the name sheep applies to many species in the genus Ovis, in everyday usage it almost always refers to Ovis aries. Numbering a little over one billion, domestic sheep are also the most numerous species of sheep. An adult female sheep is referred to as a ewe, a male as a ram or occasionally a tup, a castrated male as a wether. Sheep are most likely descended from the wild mouflon of Europe, one of the earliest animals to be domesticated for agricultural purposes, sheep are raised for fleece, meat and milk. A sheeps wool is the most widely used animal fiber, and is harvested by shearing. Ovine meat is called lamb when from younger animals and mutton when from older ones, Sheep continue to be important for wool and meat today, and are also occasionally raised for pelts, as dairy animals, or as model organisms for science. Sheep husbandry is practised throughout the majority of the inhabited world, in the modern era, Australia, New Zealand, the southern and central South American nations, and the British Isles are most closely associated with sheep production. Sheepraising has a lexicon of unique terms which vary considerably by region. Use of the sheep began in Middle English as a derivation of the Old English word scēap. A group of sheep is called a flock, herd or mob, many other specific terms for the various life stages of sheep exist, generally related to lambing, shearing, and age. Being a key animal in the history of farming, sheep have a deeply entrenched place in human culture, as livestock, sheep are most often associated with pastoral, Arcadian imagery. Sheep figure in many mythologies—such as the Golden Fleece—and major religions, in both ancient and modern religious ritual, sheep are used as sacrificial animals. Domestic sheep are relatively small ruminants, usually with a crimped hair called wool, domestic sheep differ from their wild relatives and ancestors in several respects, having become uniquely neotenic as a result of selective breeding by humans. A few primitive breeds of sheep retain some of the characteristics of their wild cousins, depending on breed, domestic sheep may have no horns at all, or horns in both sexes, or in males only. Most horned breeds have a pair, but a few breeds may have several. Another trait unique to domestic sheep as compared to wild ovines is their variation in color. Wild sheep are largely variations of brown hues, and variation within species is extremely limited, colors of domestic sheep range from pure white to dark chocolate brown, and even spotted or piebald
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Mule deer
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The mule deer is a deer indigenous to western North America, it is named for its ears, which are large like those of the mule. There are believed to be several subspecies including the black-tailed deer, unlike the related white-tailed deer, mule deer are generally more associated with the land west of the Missouri River, and more specifically with the Rocky Mountain region of North America. Mule deer have also introduced to Argentina and Kauai, Hawaii. The most noticeable differences between white-tailed and mule deer are the size of their ears, the color of their tails, in many cases, body size is also a key difference. The mule deers tail is black-tipped, whereas the whitetails is not, mule deer antlers are bifurcated, they fork as they grow, rather than branching from a single main beam, as is the case with white-tails. Each spring, a bucks antlers start to regrow almost immediately after the old antlers are shed, shedding typically takes place in mid-February, with variations occurring by locale. Although capable of running, mule deer are often seen stotting, the mule deer is the larger of the two Odocoileus species on average, with a height of 80–106 cm at the shoulders and a nose-to-tail length ranging from 1.2 to 2.1 m. Of this, the tail may comprise 11.6 to 23 cm, adult bucks normally weigh 55–150 kg, averaging around 92 kg, although trophy specimens may weigh up to 210 kg. Does are rather smaller and typically weigh from 43 to 90 kg, an exception to this is the subspecies, the Sitka black-tailed deer. This race is smaller than other mule deer, with an average weight of 54.5 kg and 36 kg in males and females. In addition to related to available shelter and food, the breeding cycle is important in understanding deer behavior. The rut or mating season begins in the fall as does go into estrus for a period of a few days and males become more aggressive. Does may mate more than one buck and go back into estrus within a month if they did not become pregnant. The gestation period is about 190–200 days, with fawns born in the spring, staying with their mothers during the summer, mule deer females usually give birth to two fawns, although if it is their first time having a fawn, they often have just one. A bucks antlers fall off during the winter, to again in preparation for the next seasons rut. The annual cycle of growth is regulated by changes in the length of the day. For a guide to identify the sex and age class of Rocky Mountain mule deer at various seasons see S1 File, for more information see the main article on deer. The size of mule deer groups follow a seasonal pattern
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Cougar
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The cougar, also commonly known as the mountain lion, puma, panther, or catamount, is a large felid of the subfamily Felinae native to the Americas. Its range, from the Canadian Yukon to the southern Andes of South America, is the greatest of any large wild terrestrial mammal in the Western Hemisphere, an adaptable, generalist species, the cougar is found in most American habitat types. It is the second-heaviest cat in the New World, after the jaguar, secretive and largely solitary by nature, the cougar is properly considered both nocturnal and crepuscular, although there are daytime sightings. The cougar is more related to smaller felines, including the domestic cat, than to any species of subfamily Pantherinae. The cougar is a predator and pursues a wide variety of prey. Primary food sources are ungulates, particularly deer, but also livestock and it also hunts species as small as insects and rodents. This cat prefers habitats with dense underbrush and rocky areas for stalking, the cougar is territorial and survives at low population densities. Individual territory sizes depend on terrain, vegetation, and abundance of prey, while large, it is not always the apex predator in its range, yielding to the jaguar, gray wolf, American black bear, and grizzly bear. It is reclusive and mostly avoids people, fatal attacks on humans are rare, but have recently been increasing in North America as more people enter their territories. Intensive hunting following European colonization of the Americas and the human development of cougar habitat has caused populations to drop in most parts of its historical range. In particular, the cougar was extirpated in eastern North America in the beginning of the 20th century, reports of eastern cougars still surface, although it was declared extirpated in 2011. With its vast range across the length of the Americas, P. concolor has dozens of names and various references in the mythology of the indigenous Americans and in contemporary culture. Currently, it is referred to as puma by most scientists, Mountain lion was a term first used in writing in 1858 from the diary of George A. Jackson of Colorado. Other names include catamount, mountain screamer, and painter, lexicographers regard painter as a primarily upper-Southern US regional variant on panther. The word panther is used to specifically designate the black panther, a melanistic jaguar or leopard, and the Florida panther. P. concolor holds the Guinness record for the animal with the greatest number of names, Cougar may be borrowed from the archaic Portuguese çuçuarana, the term was originally derived from the Tupi language susuarana, meaning similar to deer. A current form in Brazil is suçuarana and it may also be borrowed from the Guaraní language term guaçu ara or guazu ara. Less common Portuguese terms are onça-parda or leão-baio, or unusually non-native puma or leão-da-montanha, people in rural regions often refer to both the cougar and the jaguar as simply gata, and outside of the Amazon, both are colloquially referred to as simply onça by many people
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Coyote
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The coyote is a canid native to North America. It is smaller than its relative, the gray wolf, and slightly smaller than its other close relatives, the eastern wolf. It fills much of the ecological niche as the golden jackal does in Eurasia, though it is larger. The species is versatile and able to adapt to environments modified by humans, as human activity has altered the landscape, the coyotes range has expanded. In 2013, coyotes were sighted in eastern Panama for the first time, the coyote is more closely related to the common ancestor of wolves and other canids than the gray wolf. As of 2005,19 coyote subspecies are recognized, the average male coyote weighs 8 to 20 kg and the average female 7 to 18 kg. Their fur color is light gray and red or fulvous interspersed with black and white. It is highly flexible in organization, living either in a family unit or in loosely knit packs of unrelated individuals. The coyotes characteristic vocalization is a made by solitary individuals. Humans aside, cougars and gray wolves are the only serious enemies. Nevertheless, coyotes do sometimes mate with gray, eastern, or red wolves, Most recent studies show that most wolves contain some level of coyote DNA. As with other figures, the coyote uses deception and humor to rebel against social conventions. The animal was especially respected in Mesoamerican cosmology as a symbol of military might, after the European colonization of the Americas, it was reviled in Anglo-American culture as a cowardly and untrustworthy animal. Unlike wolves, which have undergone an improvement of their public image, Coyote males average 8 to 20 kg in weight, while females average 7 to 18 kg, though size varies geographically. Northern subspecies, which average 18 kg, tend to larger than the southern subspecies of Mexico. Body length ranges on average from 1.0 to 1.35 m, the largest coyote on record was a male killed near Afton, Wyoming, on November 19,1937, which measured 1.5 m from nose to tail, and weighed 34 kg. Scent glands are located at the side of the base of the tail and are a bluish-black color. The color and texture of the fur varies somewhat geographically
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Bobcat
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The bobcat is a North American cat that appeared during the Irvingtonian stage of around 1.8 million years ago. Containing 12 recognized subspecies, it ranges from southern Canada to central Mexico, the bobcat is an adaptable predator that inhabits wooded areas, as well as semidesert, urban edge, forest edge, and swampland environments. It remains in some of its range, but populations are vulnerable to local extinction by coyotes. With a gray to brown coat, whiskered face, and black-tufted ears and it is smaller on average than the Canada lynx, with which it shares parts of its range, but is about twice as large as the domestic cat. It has distinctive black bars on its forelegs and a black-tipped, stubby tail, though the bobcat prefers rabbits and hares, it hunts insects, chickens, geese and other birds, small rodents, and deer. Prey selection depends on location and habitat, season, and abundance, like most cats, the bobcat is territorial and largely solitary, although with some overlap in home ranges. It uses several methods to mark its boundaries, including claw marks. The bobcat breeds from winter into spring and has a period of about two months. Although bobcats have been hunted extensively by humans, both for sport and fur, their population has proven resilient though declining in some areas, the elusive predator features in Native American mythology and the folklore of European settlers. The Lynx genus is now accepted, and the bobcat is listed as Lynx rufus in modern taxonomic sources. Johnson et al. reported Lynx shared a clade with the puma, leopard cat, the first wave moved into the southern portion of North America, which was soon cut off from the north by glaciers. This population evolved into modern bobcats around 20,000 years ago, a second population arrived from Asia and settled in the north, developing into the modern Canada lynx. Hybridization between the bobcat and the Canada lynx may sometimes occur, the bobcat resembles other species of the Lynx genus, but is on average the smallest of the four. Its coat is variable, though generally tan to grayish-brown, with streaks on the body and dark bars on the forelegs. Its spotted patterning acts as camouflage, the ears are black-tipped and pointed, with short, black tufts. Generally, a color is seen on the lips, chin. Bobcats in the regions of the southwest have the lightest-colored coats, while those in the northern. Kittens are born well-furred and already have their spots, a few melanistic bobcats have been sighted and captured in Florida
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Horn (anatomy)
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A horn is a permanent pointed projection on the head of various animals consisting of a covering of keratin and other proteins surrounding a core of live bone. Horns are distinct to antlers which are not permanent, in mammals, true horns are found mainly among the ruminant artiodactyls, in the families Antilocapridae and Bovidae. One pair of horns is usual, however, two or more occur in a few wild species and domesticated breeds of sheep. Polycerate sheep breeds include the Hebridean, Icelandic, Jacob, Manx Loaghtan, horns usually have a curved or spiral shape, often with ridges or fluting. In many species only males have horns, horns start to grow soon after birth, and continue to grow throughout the life of the animal. Partial or deformed horns in livestock are called scurs, similar growths on other parts of the body are not usually called horns, but spurs, claws or hoofs depending on the part of the body on which they occur. These are covered with furred skin, cervidae, Most deer have antlers, which are not true horns. When fully developed, antlers are dead bone without a horn or skin covering, they are only by adults and are shed. Rhinocerotidae, The horns of rhinoceroses are made of keratin, the substance as fingernails, and grow continuously. Chamaeleonidae, Many chameleons, most notably the Jacksons Chameleon, possess horns on their skulls, ceratopsidae, The horns of the Triceratops were extensions of its skull bones although debate exists over whether they had a keratin covering. Horned lizards, These lizards have horns on their heads which have a keratin covering over a bony core. Insects, Some insects have horn-like structures on the head or thorax and these are pointed outgrowths of the hard chitinous exoskeleton. Some have greatly enlarged jaws, also made of chitin, canidae, Golden jackals are known to occasionally develop a horny growth on the skull, which is associated with magical powers in south-eastern Asia. Many mammal species in various families have tusks, which serve the same functions as horns. These include the Moschidae, Suidae, Proboscidea, Monodontidae and Odobenidae, Polled animals or pollards are those of normally-horned species whose horns have been removed, or which have not grown. In some cases animals have small horny growths in the skin where their horns would be – these are known as scurs. Cutaneous horns are the examples of horns growing on people. They are most often benign growths and can be removed by a razor, cases of people growing horns have been historically described, sometimes with mythical status
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Poaceae
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Poaceae or Gramineae is a large and nearly ubiquitous family of monocotyledonous flowering plants known as grasses. Poaceae includes the cereal grasses, bamboos and the grasses of natural grassland and cultivated lawns, Grasses have stems that are hollow except at the nodes and narrow alternate leaves borne in two ranks. The lower part of each leaf encloses the stem, forming a leaf-sheath, with ca 780 genera and around 12,000 species, Poaceae are the fifth-largest plant family, following the Asteraceae, Orchidaceae, Fabaceae and Rubiaceae. Grasslands such as savannah and prairie grasses are dominant are estimated to constitute 40. 5% of the land area of the Earth, excluding Greenland. Grasses are also an important part of the vegetation in many habitats, including wetlands, forests. Though commonly called grasses, seagrasses, rushes, and sedges fall outside this family, the rushes and sedges are related to the Poaceae, being members of the order Poales, but the seagrasses are members of order Alismatales. The name Poaceae was given by John Hendley Barnhart in 1895, based on the tribe Poeae described in 1814 by Robert Brown, the term is derived from the Ancient Greek πόα. Grasses include some of the most versatile plant life-forms, a cladogram shows subfamilies and approximate species numbers in brackets, Before 2005, fossil findings indicated that grasses evolved around 55 million years ago. Recent findings of grass-like phytoliths in Cretaceous dinosaur coprolites have pushed this back to 66 million years ago. In 2011, revised dating of the origins of the rice tribe Oryzeae suggested a date as early as 107 to 129 Mya, a multituberculate mammal with grass-eating adaptations seems to suggest that grasses were already around at 120 mya. This separation occurred within the short time span of about 4 million years. Grass leaves are always alternate and distichous, and have parallel veins. Each leaf is differentiated into a lower sheath hugging the stem, the leaf blades of many grasses are hardened with silica phytoliths, which discourage grazing animals, some, such as sword grass, are sharp enough to cut human skin. A membranous appendage or fringe of hairs called the ligule lies at the junction between sheath and blade, preventing water or insects from penetrating into the sheath, flowers of Poaceae are characteristically arranged in spikelets, each having one or more florets. The spikelets are further grouped into panicles or spikes, the part of the spikelet that bears the florets is called the rachilla. A spikelet consists of two bracts at the base, called glumes, followed by one or more florets, a floret consists of the flower surrounded by two bracts, one external—the lemma—and one internal—the palea. The flowers are usually hermaphroditic—maize being an important exception—and anemophilous or wind-pollinated, the perianth is reduced to two scales, called lodicules, that expand and contract to spread the lemma and palea, these are generally interpreted to be modified sepals. This complex structure can be seen in the image on the right, the fruit of grasses is a caryopsis, in which the seed coat is fused to the fruit wall
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Cyperaceae
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The Cyperaceae are a family of monocotyledonous graminoid flowering plants known as sedges, which superficially resemble grasses and rushes. The family is large, with some 5,500 known species described in about 90 genera and these species are widely distributed, with the centers of diversity for the group occurring in tropical Asia and tropical South America. While sedges may be growing in almost all environments, many are associated with wetlands. Ecological communities dominated by sedges are known as sedgelands, features distinguishing members of the sedge family from grasses or rushes are stems with triangular cross-sections and leaves that are spirally arranged in three ranks. Some well-known sedges include the chestnut and the papyrus sedge. This family also includes cotton-grass, spike-rush, sawgrass, nutsedge or nutgrass, and white star sedge
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Forb
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A forb is a herbaceous flowering plant that is not a graminoid. The term is used in biology and in ecology, especially in relation to grasslands. Forb is derived from the Greek φορβή, pasture or fodder, the spelling phorb is sometimes used, and in older usage this sometimes includes graminids and other plants currently not regarded as forbs. Forbs are members of a guild – a group of plant species with similar growth form. In certain contexts in ecology, guild membership may often be more important than the relationships between organisms. In addition to its use in ecology, the term forb may be used for subdividing popular guides to wildflowers, distinguishing them from other such as grasses, sedges, shrubs. Some examples of forbs are clover, sunflower, daylily, dicotyledon Herbaceous plant Overgrazing United States Department of Agriculture Natural Resources Conservation Service link to Growth habits Codes and Definitions
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Desert
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A desert is a barren area of land where little precipitation occurs and consequently living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to the processes of denudation, about one third of the land surface of the world is arid or semi-arid. This includes much of the regions where little precipitation occurs. Deserts can be classified by the amount of precipitation falls, by the temperature that prevails. Deserts are formed by weathering processes as large variations in temperature between day and night put strains on the rocks which consequently break in pieces, although rain seldom occurs in deserts, there are occasional downpours that can result in flash floods. Rain falling on hot rocks can cause them to shatter and the resulting fragments and this picks up particles of sand and dust and wafts them aloft in sand or dust storms. Wind-blown sand grains striking any solid object in their path can abrade the surface, rocks are smoothed down, and the wind sorts sand into uniform deposits. The grains end up as level sheets of sand or are piled high in billowing sand dunes, other deserts are flat, stony plains where all the fine material has been blown away and the surface consists of a mosaic of smooth stones. These areas are known as desert pavements and little further erosion takes place, other desert features include rock outcrops, exposed bedrock and clays once deposited by flowing water. Temporary lakes may form and salt pans may be left when waters evaporate, there may be underground sources of water in the form of springs and seepages from aquifers. Where these are found, oases can occur, plants and animals living in the desert need special adaptations to survive in the harsh environment. Plants tend to be tough and wiry with small or no leaves, water-resistant cuticles, some annual plants germinate, bloom and die in the course of a few weeks after rainfall while other long-lived plants survive for years and have deep root systems able to tap underground moisture. Animals need to cool and find enough food and water to survive. Many are nocturnal and stay in the shade or underground during the heat of the day and they tend to be efficient at conserving water, extracting most of their needs from their food and concentrating their urine. Some animals remain in a state of dormancy for long periods and they then reproduce rapidly while conditions are favorable before returning to dormancy. People have struggled to live in deserts and the surrounding lands for millennia. Nomads have moved their flocks and herds to wherever grazing is available, the cultivation of semi-arid regions encourages erosion of soil and is one of the causes of increased desertification. Many trade routes have been forged across deserts, especially across the Sahara Desert, large numbers of slaves were also taken northwards across the Sahara
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Behavioral ecology
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Behavioral ecology, also spelled behavioural ecology, is the study of the evolutionary basis for animal behavior due to ecological pressures. If an organism has a trait which provides them with an advantage in its environment. Adaptive significance therefore refers to the qualities, any given modified trait conveys. e. Individuals are always in competition with others for limited resources, including food, territories, conflict will occur between predators and prey, between rivals for mates, between siblings, mates, and even between parents and their offspring. The value of a social behavior depends in part on the behavior of an animals neighbors. For example, the more likely a male is to back down from a threat. The more likely, however, that a rival will attack if threatened, when a population exhibits a number of interacting social behaviors such as this, it can evolve a stable pattern of behaviors known as an evolutionarily stable strategy. In other words, at equilibrium every player should play the best strategic response to each other, when the game is two player and symmetric each player should play the strategy which is the best response to itself. Therefore, the ESS is considered to be the end point subsequent to the interactions. Behavioral evolution is therefore influenced by both the environment and interactions between other individuals. An example of how changes in geography can make a strategy susceptible to alternative strategies is the parasitization of the African honey bee, the term economic defendability was first introduced by Jerram Brown in 1964. Economic defendability states that defense of a resource have costs, such as energy expenditure or risk of injury, territorial behavior arises when benefits are greater than the costs. Studies of the golden-winged sunbird have validated the concept of economic defendability, when resources are at low density, the gains from excluding others may not be sufficient to pay for the cost of territorial defense. In contrast, when availability is high, there may be so many intruders that the defender would have no time to make use of the resources made available by defense. Sometimes the economics of resource competition favors shared defense, an example is the feeding territories of the white wagtail. The white wagtails feed on insects washed up by the river onto the bank, if any intruders harvested their territory then the prey would quickly become depleted, but sometimes territory owners tolerate a second bird, known as a satellite. The two sharers would then move out of phase with one another, resulting in decreased feeding rate but also increased defense, one of the major models used to predict the distribution of competing individuals amongst resource patches is the ideal free distribution model. Within this model, resource patches can be of variable quality, an experiment by Manfred Malinski in 1979 demonstrated that feeding behavior in three-spined sticklebacks follows an ideal free distribution
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Dominance hierarchy
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Dominance hierarchy arises when members of a social group interact, often aggressively, to create a ranking system. In social living groups, members are likely to compete for access to limited resources, rather than fighting each time they meet, relative relationships are formed between members of the same sex. Based on repetitive interactions a social order is created that is subject to each time a dominant animal is challenged by a subordinate one. The manifestation of intrasexual conflict can be observed in one of two systems, the social order can be either egalitarian or despotic. In a linear ranking system, every member of the gender is recognized as either dominant or submissive relative to other member. For example, groups of spotted hyenas and brown hyenas both demonstrate linear dominance, in a despotic system, one member is considered dominant while all other members of the living group are equally submissive. Examples of despotic social systems are found in meerkats, wolves, male gorillas, Neolamprologus pulcher, patterns of animal conflict reveal important insights into the evolution of behavior and the influence of behavior on relationships that develop in a social group. Pair-wise interactions have been observed to promote social hierarchies within groups of animals where individuals with successful agonistic behaviors often achieve dominance and these behaviors, which include aggression, threat displays, and fighting, are indicative of competition over resources, such as food or mates. However, they may vary based on the situation and position of the individuals involved, animal decisions regarding involvement in conflict are defined by the interplay between the costs and benefits of agonistic behaviors. When initially developed, game theory, the study of optimal strategies during pair-wise conflict, was grounded in the assumption that animals engaged in conflict were of equal fighting ability. Modifications, however, have provided increased focus on the differences between the capabilities of animals and raised questions about their evolutionary development. These differences are believed to determine the outcomes of fights, their intensity, the asymmetries between individuals have been categorized into three types of interactions. Resource-holding potential, Animals that are able to defend resources often win without much physical contact. Resource value, Animals more invested in a resource are likely to invest more in the fight despite potential for incurring higher costs and this can be explained further by looking at the example of the common shrews. If one participant believes he is the resident of the territory, however, if both shrews believe they are the true territory holder, the one with the greater need for food, and therefore, one that values the resource more, is most likely to win. As expected, the individual who emerges triumphant is rewarded with the dominant status, however, the costs incurred to the defeated, which include loss of reproductive opportunities and quality food, can hinder the individual’s fitness. In order to minimize losses, animals generally retreat from fighting or displaying fighting ability unless there are obvious cues indicating victory. These often involve characteristics that provide an advantage during agonistic behavior, such as size of body, displays, red stags, for example, engage in exhausting roaring contests to exhibit their strength
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Hunting
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Hunting is the practice of killing or trapping animals, or pursuing or tracking them with the intent of doing so. Hunting wildlife or feral animals is most commonly done by humans for food, recreation, to predators that are dangerous to humans or domestic animals. Lawful hunting is distinguished from poaching, which is the killing, trapping or capture of the hunted species. The species that are hunted are referred to as game or prey and are usually mammals, Hunting can also be a means of pest control. However, hunting has also contributed to the endangerment, extirpation and extinction of many animals. The pursuit, capture and release, or capture for food of fish is called fishing, the practice of foraging or gathering materials from plants and mushrooms is also considered separate from hunting. The word hunt serves as both a noun and a verb, the noun has been dated to the early 12th century, act of chasing game, from the verb hunt. The meaning of a body of persons associated for the purpose of hunting with a pack of hounds is first recorded in the 1570s, meaning the act of searching for someone or something is from about 1600. The verb, Old English huntian to chase game, perhaps developed from hunta hunter, is related to hentan to seize, from Proto-Germanic huntojan, the general sense of search diligently is first recorded c. Hunting has a history and may well pre-date the rise of the species Homo sapiens. Evidence from western Kenya suggests that hunting has been occurring for more two million years. Furthermore, evidence exists that hunting may have one of the multiple environmental factors leading to the Holocene extinction of megafauna. North American megafauna extinction was coincidental with the Younger Dryas impact event, however, in other locations such as Australia, humans are thought to have played a very significant role in the extinction of the Australian megafauna that was widespread prior to human occupation. The closest surviving relatives of the species are the two species of Pan, the common chimpanzee and bonobos. Common chimpanzees have a diet that includes troop hunting behaviour based on beta males being led by an alpha male. Bonobos have also observed to occasionally engage in group hunting. With the establishment of language, culture, and religion, hunting became a theme of stories and myths, as well as such as dance. Hunting was a component of hunter-gatherer societies before the domestication of livestock
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Livestock
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Livestock are domesticated animals raised in an agricultural setting to produce commodities such as food, fiber, and labor. The term is used to refer solely to those raised for food. In recent years, some organizations have also raised livestock to promote the survival of rare breeds, animal husbandry practices have varied widely across cultures and time periods. Originally, livestock were not confined by fences or enclosures, but these practices have largely shifted to intensive animal farming and these practices increase yield of the various commercial outputs, but have led to increased concerns about animal welfare and environmental impact. Livestock production continues to play an economic and cultural role in numerous rural communities. Livestock as a word was first used between 1650 and 1660, as a merger between the live and stock. Older English sources, such as the King James Version of the Bible, the word cattle is derived from Old North French catel, which meant all kinds of movable personal property, including livestock, which was differentiated from immovable real estate. In later English, sometimes smaller livestock such as chickens and pigs were referred to as small cattle, today, the modern meaning of cattle, without a modifier, usually refers to domesticated bovines, but sometimes livestock refers only to this subgroup. Legal definition United States federal legislation sometimes more narrowly defines the term to make specified agricultural commodities either eligible or ineligible for a program or activity, for example, the Livestock Mandatory Reporting Act of 1999 defines livestock only as cattle, swine, and sheep. Animal-rearing originated during the transition to settled farming communities from hunter-gatherer lifestyles. Animals are domesticated when their breeding and living conditions are controlled by humans, over time, the collective behaviour, lifecycle and physiology of livestock have changed radically. Many modern farm animals are unsuited to life in the wild, dogs were domesticated in East Asia about 15,000 years ago. Goats and sheep were domesticated around 8000 BC in Asia, swine or pigs were domesticated by 7000 BC in the Middle East and China. The earliest evidence of horse domestication dates to around 4000 BC, the term livestock is nebulous and may be defined narrowly or broadly. Broadly, livestock refers to any breed or population of animal kept by humans for a useful and this can mean domestic animals, semidomestic animals, or captive wild animals. Semidomesticated refers to animals which are only lightly domesticated or of disputed status and these populations may also be in the process of domestication. Some people may use the term livestock to refer to only used for red meat. Livestock are used by humans for a variety of purposes, many of which have an economic value, Livestock products include, Meat A useful form of dietary protein and energy, meat is the edible tissue of the animal carcass
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Frederick Russell Burnham
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Frederick Russell Burnham DSO was an American scout and world-traveling adventurer. He is known for his service to the British South Africa Company and to the British Army in colonial Africa and he helped inspire the founding of the international Scouting Movement. Burnham was born on a Dakota Sioux Indian reservation in Minnesota where he learned the ways of American Indians as a boy. By the age of 14, he was supporting himself in California, while also learning scouting from some of the last of the cowboys, Burnham had little formal education, never finishing high school. After moving to the Arizona Territory in the early 1880s, he was drawn into the Pleasant Valley War and he escaped and later worked as a civilian tracker for the United States Army in the Apache Wars. Feeling the need for new adventures, Burnham took his family to southern Africa in 1893, Burnham distinguished himself in several battles in Rhodesia and South Africa and became Chief of Scouts. Despite his U. S. citizenship, his title was British. He had become friends with Baden-Powell during the Second Matabele War in Rhodesia, teaching him outdoor skills, Burnham returned to the United States, where he became involved in national defense efforts, business, oil, conservation, and the Boy Scouts of America. During World War I, Burnham was selected as an officer and recruited volunteers for a U. S. Army division similar to the Rough Riders, for political reasons, the unit was disbanded without seeing action. After the war, Burnham and his business partner John Hays Hammond formed the Burnham Exploration Company, Burnham joined several new wilderness conservation organizations, including the California State Parks Commission. In the 1930s, he worked with the BSA to save the big horn sheep from extinction and this effort led to the creation of the Kofa and Cabeza Prieta National Wildlife Refuges in Arizona. He earned the BSAs highest honor, the Silver Buffalo Award, in 1936, to symbolise the friendship between Burnham and Baden-Powell, the mountain beside Mount Baden-Powell in California was formally named Mount Burnham in 1951. Burnham was born on May 11,1861 on a Dakota Sioux Indian reservation in Minnesota, to a family living near the small pioneer town of Tivoli. His father, the Reverend Edwin Otway Burnham, was a Presbyterian minister educated and ordained in New York, he was born in Ghent, Kentucky. His mother Rebecca Russell Burnham had spent most of her childhood in Iowa, having emigrated with her family from Westminster and she hid Frederick in a basket of green corn husks in a corn field and fled for her life. Once the Sioux attack had been repulsed, she returned to find their house burned down, the young Burnham attended schools in Iowa. There he met Blanche Blick, whom he later married, Two years later, Edwin died, leaving the family destitute. For the next few years, Burnham worked as a messenger for the Western Union Telegraph Company in California
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Scouting in Arizona
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Scouting in Arizona has a long history, from the 1910s to the present day, serving thousands of youth in programs that suit the environment in which they live. Boy Scouting was founded by Robert Baden-Powell in England and co-founded by the American Scout Major Frederick Russell Burnham, Boy Scouting was brought to the United States by William D. Boyce. He incorporated the Boy Scouts of America on February 8,1910, the Boy Scouts of America was chartered by Congress on June 15,1916, This is the same year as the first Boy Scout Council in Arizona was formed with the Prescott Council. Burnham served as the Honorary President of the Arizona Boy Scouts throughout the 1940s until his death in 1947, the first two Boy Scout troops in Arizona Territory were organized in Prescott, in September 1910 and in Tombstone at almost the same time. In Prescott, E. P. Cole of Whipple Barracks was the first scoutmaster, Arizona Territorial Historian Sharlot Hall was an honorary member of the Tombstone troop. Scouting came to Phoenix in the fall 1910 with Clarence R. Craig as the scoutmaster, other scout troops were formed, in Bisbee in early 1911. and in St. Joseph and Snowflake about the same time. Harold Steele, principal of the then new Tucson High School, in March 1912, the LDS Church published their first lessons for the MIA Scouts in the Improvement Era. On May 21,1913 the LDS Church was invited by the Boy Scout National Council to become the first Chartered Sponsored Organization in their movement, the Boy Scouts of America program was then adopted in all LDS Church congregations as part of their youth program. Each LDS Church congregation in Arizona organized a scout troop, in April 1921 the eight LDS troops in the Maricopa Stake and the Methodist troop met in at the Coffee Cup in Mesa to organize the Apache Council. This was the council in Arizona. George A. Johnson was the first Council President, edwin M. LeBaron was the first Field Commissioner. Their first summer camp was held on Sycamore Creek near Payson, on September 16,1921, the board of the Apache Council met with scouters from Phoenix at the Tempe National Bank to reorganized into the Roosevelt Council, to be headquartered in Phoenix. Tim Murray from Galveston Texas, was the first professional Scout Executive, the 1922 summer camp was at Pineair. The name, Camp Geronimo, is used by the Grand Canyon Council camp although the location has changed several times. Throughout the 1940s, Frederick Russell Burnham served as the Honorary President of the Roosevelt Council Boy Scouts, the Roosevelt Council changed its name to the Theodore Roosevelt Council. In 1993 the Theodore Roosevelt Council and the Grand Canyon Council merged with the Phoenix council assuming the current name, the Nassau County Council in New York was renamed to the Theodore Roosevelt Council in 1997. In 1936, Boy Scouts in Arizona mounted a campaign to save the Bighorn Sheep. The Scouts first became interested in the sheep through the efforts of Major Frederick Russell Burnham, Burnham observed that fewer than 150 of these sheep still lived in the Arizona mountains
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Franklin D. Roosevelt
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Franklin Delano Roosevelt, commonly known as FDR, was an American statesman and political leader who served as the 32nd President of the United States from 1933 until his death in 1945. A Democrat, he won a record four presidential elections and emerged as a figure in world events during the mid-20th century. He directed the United States government during most of the Great Depression and he is often rated by scholars as one of the three greatest U. S. Presidents, along with George Washington and Abraham Lincoln. Roosevelt was born in 1882 to an old, prominent Dutch family from Dutchess County and he attended the elite educational institutions of Groton School, Harvard College, and Columbia Law School. At age 23 in 1905, he married Eleanor Roosevelt, and he entered politics in 1910, serving in the New York State Senate, and then as Assistant Secretary of the Navy under President Woodrow Wilson. In 1920, Roosevelt was presidential candidate James M. Coxs running mate and he was in office from 1929 to 1933 and served as a reform governor, promoting the enactment of programs to combat the depression besetting the United States at the time. In the 1932 presidential election, Roosevelt defeated incumbent Republican president Herbert Hoover in a landslide to win the presidency, Roosevelt took office while in the United States was in the midst of the worst economic crisis in its history. Energized by his victory over polio, FDR relied on his persistent optimism and activism to renew the national spirit. He created numerous programs to support the unemployed and farmers, and to labor union growth while more closely regulating business. His support for the repeal of Prohibition in 1933 added to his popularity, the economy improved rapidly from 1933–37, but then relapsed into a deep recession in 1937–38. The bipartisan Conservative Coalition that formed in 1937 prevented his packing the Supreme Court, when the war began and unemployment ended, conservatives in Congress repealed the two major relief programs, the WPA and CCC. However, they kept most of the regulations on business, along with several smaller programs, major surviving programs include the Securities and Exchange Commission, the Wagner Act, the Federal Deposit Insurance Corporation and Social Security. His goal was to make America the Arsenal of Democracy, which would supply munitions to the Allies, in March 1941, Roosevelt, with Congressional approval, provided Lend-Lease aid to Britain and China. He supervised the mobilization of the U. S. economy to support the war effort, as an active military leader, Roosevelt implemented a war strategy on two fronts that ended in the defeat of the Axis Powers and initiate the development of the worlds first atomic bomb. His work also influenced the creation of the United Nations. Roosevelts physical health declined during the war years, and he died 11 weeks into his fourth term. One of the oldest Dutch families in New York State, the Roosevelts distinguished themselves in other than politics. One ancestor, Isaac Roosevelt, had served with the New York militia during the American Revolution, Roosevelt attended events of the New York society Sons of the American Revolution, and joined the organization while he was president
45.
San Andres National Wildlife Refuge
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The San Andres National Wildlife Refuge is located in the southern San Andres Mountains of southcentral New Mexico, USA. The refuge, which lies within the northernmost extension of the Chihuahuan Desert, has elevations ranging from 4,200 feet to 8,239 feet feet, Refuge habitats vary from creosote and Chihuahuan desert grasslands in the bajadas to pinyon-juniper woodlands at higher elevations. A few springs, seeps, and seasonal streams provide water for wildlife, San Andres NWR is completely surrounded by the White Sands Missile Range and is closed to the public for security reasons. The San Andres National Wildlife Refuge preserves the largest intact Chihuahuan desert mountain range in the U. S, the refuge runs 21 miles north to south at the southern end of the San Andres Mountains. San Andres Peak is the highest point at 8,239 feet, bennett and Big Brushy Mountains rise to more than 7,000 feet. The range is a fault-block tilted to the west, the eastern slopes of the San Andres rise sharply from the Tularosa Basin now largely part of the White Sands military base. The western slopes are more gradual, merging into the Jornada del Muerto, the refuge is in the Upper Sonoran life zone characterized by semi-desert vegetation and grassland. One hundred and seventy two species of birds, including 5 species of hummingbirds, have seen on the refuge. Large mammals include deer, mountain lion, desert bighorn sheep, black bear. On rare occasions, javelina have been seen, the average precipitation on the refuge is 13 inches annually, although it is highly variable ranging from about 7 to 25 inches per year. Most precipitation comes in the summer, at least 10 springs and spring complexes on the refuge provide water for wildlife and create riparian zones with cottonwood, willow, and ash trees. Some of the springs have sufficient flow to create live streams that run for several hundred yards before becoming dry washes with water only after major rainstorms, the springs are located at elevations of 4,900 feet to 6,000 feet in elevation. The San Andres National Wildlife Refuge was created to preserve the desert bighorn sheep which was becoming rare in much of its range, at the time of the creation of the refuge, in 1941, the population of desert bighorn sheep was 33. With protection, this increased to 140 in 1950 before declining to 70 after a severe drought. Grazing on the refuge was ended in 1952 and the numbers of the herd increased to about 200 in the 1970s, disease then struck the herd and only one lone female remained alive in 1997. Beginning in 1999, desert bighorns were re-introduced into San Andres from other areas, San Andres NWR is the largest area of protected land for desert bighorns in New Mexico. The oryx, a large desert antelope from Africa and the Arabian peninsula, was introduced into White Sands Missile Range in 1969 and their numbers quickly grew to about 4,000 and their range expanded into San Andres National Wildlife Refuge. By 1997, at least 50 oryx inhabited the refuge, oryx successfully competed for scarce resources with bighorn sheep and mule deer because they need little or no water to survive, getting their moisture from the plants they eat
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Habitat
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A habitat is an ecological or environmental area that is inhabited by a particular species of animal, plant, or other type of organism. The term typically refers to the zone in which the organism lives and it is the natural environment in which an organism lives, or the physical environment that surrounds a species population. Every organism has certain habitat needs for the conditions in which it will thrive, habitat types include polar, temperate, subtropical and tropical. The terrestrial vegetation type may be forest, steppe, grassland, the word habitat has been in use since about 1755 and derives from the Latin third-person singular present indicative of habitāre, to inhabit, from habēre, to have or to hold. Habitat can be defined as the environment of an organism. It is similar in meaning to a biotope, an area of environmental conditions associated with a particular community of plants. Generally speaking, animal communities are reliant on specific types of plant communities, some plants and animals are generalists, and their habitat requirements are met in a wide range of locations. The small white butterfly for example is found on all the continents of the world apart from Antarctica and its larvae feed on a wide range of Brassicas and various other plant species, and it thrives in any open location with diverse plant associations. Disturbance is important in the creation of biodiverse habitats, in the absence of disturbance, a climax vegetation cover develops that prevents the establishment of other species. Lightning strikes and toppled trees in tropical forests allow species richness to be maintained as pioneering species move in to fill the gaps created. Similarly coastal habitats can become dominated by kelp until the seabed is disturbed by a storm, another cause of disturbance is when an area may be overwhelmed by an invasive introduced species which is not kept under control by natural enemies in its new habitat. Terrestrial habitat types include forests, grasslands, wetlands and deserts, within these broad biomes are more specific habitats with varying climate types, temperature regimes, soils, altitudes and vegetation types. Many of these habitats grade into each other and each one has its own communities of plants. A habitat may suit a particular species well, but its presence or absence at any particular location depends to some extent on chance, on its dispersal abilities, freshwater habitats include rivers, streams, lakes, ponds, marshes and bogs. Although some organisms are found across most of these habitats, the majority have more specific requirements, similarly, aquatic plants can be floating, semi-submerged, submerged or grow in permanently or temporarily saturated soils besides bodies of water. Marine habitats include brackish water, estuaries, bays, the sea, the intertidal zone. Further variations include rock pools, sand banks, mudflats, brackish lagoons, sandy and pebbly beaches, the benthic zone or seabed provides a home for both static organisms, anchored to the substrate, and for a large range of organisms crawling on or burrowing into the surface. A desert is not the kind of habitat that favours the presence of amphibians, with their requirement for water to keep their skins moist, nevertheless, some frogs live in deserts, creating moist habitats underground and hibernating while conditions are adverse
