1.
Conservation status
–
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.
Least Concern
–
A least concern species is one which has been categorized by the International Union for Conservation of Nature as evaluated but not qualified for any other category. As such they do not qualify as threatened, near threatened, species cannot be assigned the Least Concern category unless they have had their population status evaluated. That is, adequate information is needed to make a direct, or indirect, since 2001 the category has had the abbreviation LC, following the IUCN2001 Categories & Criteria. However, around 20% of least concern taxa in the IUCN database use the code LR/lc, prior to 2001 least concern was a subcategory of the Lower Risk category and assigned the code LR/lc or. While least concern is not considered a red listed category by the IUCN, the number of animal species listed in this category totals 14033. There are also 101 animal subspecies listed and 1500 plant taxa, there are also two animal subpopulations listed, the Australasian and Southern African subpopulations of spiny dogfish. No fungi or protista have the classification, though only four species in those kingdoms have been evaluated by the IUCN, humans qualify for this category, and in 2008 were formally assessed as such by the IUCN
3.
IUCN Red List
–
The IUCN Red List of Threatened Species, founded in 1964, is the worlds most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the main authority on the conservation status of species. A series of Regional Red Lists are produced by countries or organizations, the IUCN Red List is set upon precise criteria to evaluate the extinction risk of thousands of species and subspecies. These criteria are relevant to all species and all regions of the world, the aim is to convey the urgency of conservation issues to the public and policy makers, as well as help the international community to try to reduce species extinction. Major species assessors include BirdLife International, the Institute of Zoology, the World Conservation Monitoring Centre, collectively, assessments by these organizations and groups account for nearly half the species on the Red List. The IUCN aims to have the category of every species re-evaluated every five years if possible, the 1964 IUCN Red List of Threatened Plants used the older pre-criteria Red List assessment system. Plants listed may not, therefore, appear in the current Red List, IUCN advise that is best to check both the online Red List and the 1997 plants Red List publication. The 2006 Red List, released on 4 May 2006 evaluated 40,168 species as a whole, plus an additional 2,160 subspecies, varieties, aquatic stocks, on 12 September 2007, the World Conservation Union released the 2007 IUCN Red List of Threatened Species. Russ Mittermeier, chief of Swiss-based IUCNs Primate Specialist Group, stated that 16,306 species are endangered with extinction,188 more than in 2006, the Red List includes the Sumatran orangutan in the Critically Endangered category and the Bornean orangutan in the Endangered category. The study shows at least 1,141 of the 5,487 mammals on Earth are known to be threatened with extinction, and 836 are listed as Data Deficient. The Red List of 2012 was released 19 July 2012 at Rio+20 Earth Summit, nearly 2,000 species were added, the IUCN assessed a total of 63,837 species which revealed 19,817 are threatened with extinction. With 3,947 described as endangered and 5,766 as endangered. At threat are 41% of amphibian species, 33% of reef-building corals, 30% of conifers, 25% of mammals, the IUCN Red List has listed 132 species of plants and animals from India as Critically Endangered. Extinct – No known individuals remaining, extinct in the wild – Known only to survive in captivity, or as a naturalized population outside its historic range. Critically endangered – Extremely high risk of extinction in the wild, Endangered – High risk of extinction in the wild. Vulnerable – High risk of endangerment in the wild, near threatened – Likely to become endangered in the near future. Does not qualify for a more at-risk category, 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
4.
Taxonomy (biology)
–
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
5.
Animal
–
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
–
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.
Actinopterygii
–
Actinopterygii /ˌæktᵻnˌɒptəˈrɪdʒi. aɪ/, or the ray-finned fishes, constitute a class or subclass of the bony fishes. These actinopterygian fin rays attach directly to the proximal or basal skeletal elements, the radials, numerically, actinopterygians are the dominant class of vertebrates, comprising nearly 99% of the over 30,000 species of fish. They are ubiquitous throughout freshwater and marine environments from the sea to the highest mountain streams. Extant species can range in size from Paedocypris, at 8 mm, to the ocean sunfish, at 2,300 kg. Ray-finned fishes occur in variant forms. The main features of a typical ray-finned fish are shown in the diagram at the left. In nearly all ray-finned fish, the sexes are separate, development then proceeds with a free-swimming larval stage. However other patterns of ontogeny exist, with one of the commonest being sequential hermaphroditism, in most cases this involves protogyny, fish starting life as females and converting to males at some stage, triggered by some internal or external factor. This may be advantageous as females become less prolific as they age while male fecundity increases with age, protandry, where a fish converts from male to female, is much less common than protogyny. Most families use external rather than internal fertilization, of the oviparous teleosts, most do not provide parental care. Viviparity is relatively rare and is found in about 6% of teleost species, male territoriality preadapts a species for evolving male parental care. There are a few examples of fish that self-fertilise, the mangrove rivulus is an amphibious, simultaneous hermaphrodite, producing both eggs and spawn and having internal fertilisation. This mode of reproduction may be related to the habit of spending long periods out of water in the mangrove forests it inhabits. Males are occasionally produced at temperatures below 19 °C and can fertilise eggs that are spawned by the female. This maintains genetic variability in a species that is otherwise highly inbred, the earliest known fossil actinopterygiian is Andreolepis hedei, dating back 420 million years. Remains have been found in Russia, Sweden, and Estonia, actinopterygians are divided into the subclasses Chondrostei and Neopterygii. The Neopterygii, in turn, are divided into the infraclasses Holostei and Teleostei, during the Mesozoic and Cenozoic the teleosts in particular diversified widely, and as a result, 96% of all known fish species are teleosts. The cladogram shows the groups of actinopterygians and their relationship to the terrestrial vertebrates that evolved from a related group of fish
8.
Cypriniformes
–
Cypriniformes is an order of ray-finned fish, including the carps, minnows, loaches and relatives. This order contains 11-12 families, over 400 genera, and more than 4,250 species, with new species being described every few months or so and they are most diverse in southeastern Asia, and are entirely absent from Australia and South America. Their closest living relatives are the Characiformes, the Gymnotiformes and the Siluriformes, like other orders of the Ostariophysi, fishes of cypriniformes possess a Weberian apparatus. They differ from most of their relatives in having only a dorsal fin on their back, further differences are the Cypriniformes unique kinethmoid, a small median bone in the snout, and the lack of teeth in the mouth. Instead, they have convergent structures called pharyngeal teeth in the throat, while other groups of fish, such as cichlids, also possess pharyngeal teeth, the cypriniformes teeth grind against a chewing pad on the base of the skull, instead of an upper pharyngeal jaw. The most notable family placed here is Cyprinidae which make up two-thirds of the orders diversity and this is one of the largest families of fish, and is widely distributed across Africa, Eurasia, and North America. Most species are freshwater inhabitants, but a considerable number are found in brackish water, such as roach. At least one species is found in saltwater, the Pacific redfin, brackish water and marine cyprinids are invariably anadromous, swimming upstream into rivers to spawn. Sometimes separated as family Psilorhynchidae, they seem to be specially-adapted fishes of Cyprinidae, Balitoridae and Gyrinocheilidae are families of mountain stream fishes feeding on algae and small invertebrates. They are found only in tropical and subtropical Asia, while the former are a speciose group, the latter contain only a handful of species. The suckers are found in temperate North America and eastern Asia and these large fishes are similar to carps in appearance and ecology. Members of Cobitidae common across Eurasia and parts of North Africa, historically these included all the forms now placed in the superorder Ostariophysi except the catfish, which were placed in the order Siluriformes. By this definition, the Cypriniformes were paraphyletic, so recently the orders Gonorhynchiformes, Characiformes, the families of Cypriniformes are traditionally divided into two superfamilies. Superfamily Cyprinioidea contains the carps and minnows and, according to some, Catostomoidea is usually treated as a junior synonym of Cobitioidea. But it seems that it could be split off the Catostomidae and Gyrinocheilidae in a distinct superfamily, while the Cyprinioidea seem more primitive than the loach-like forms, they were apparently successful enough never to shift from the original ecological niche of the basal Ostariophysi. Yet, from the ecomorphologically conservative main lineage apparently at least two major radiations branched off and these diversified from the lowlands into torrential river habitats, acquiring similar habitus and adaptations in the process. The mountain carps are highly apomorphic Cyprinidae, perhaps close to true carps, a systematic list, from the most ancient to the most modern lineages, can thus be given as, Superfamily Cyprinoidei Family Cyprinidae Bonaparte,1840 and minnows incl. This is evidenced not only by physiological details, but their great distribution, the earliest that Cypriniformes might have diverged from Characiphysi is thought to be about the Early Triassic, about 250 million years ago
9.
Cyprinidae
–
The Cyprinidae are the family of freshwater fishes, collectively called cyprinids, that includes the carps, the true minnows, and their relatives. The family belongs to the ostariophysian order Cypriniformes, of whose genera, the family name is derived from the Ancient Greek kyprînos. Cyprinids are stomachless fish with toothless jaws, even so, food can be effectively chewed by the gill rakers of the specialized last gill bow. These pharyngeal teeth allow the fish to make chewing motions against a chewing plate formed by a process of the skull. The pharyngeal teeth are species-specific and are used by specialists to determine species, strong pharyngeal teeth allow fish such as the common carp and ide to eat hard baits such as snails and bivalves. Hearing is a sense in the cyprinids since they have the Weberian organ. The vertebral processes of the Weberian organ also permit a cyprinid to detect changes in motion of the gas due to atmospheric conditions or depth changes. The cyprinids are considered physostomes because the pneumatic duct is retained in adult stages, Cyprinids are native to North America, Africa, and Eurasia. The largest known cyprinid is the giant barb, which may grow up to 3 m in length and 300 kg in weight, other very large species that can surpass 2 m are the golden mahseer and mangar. The largest North American species is the Colorado pikeminnow, which can reach up to 1.8 m in length, conversely, many species are smaller than 5 cm. The smallest known fish is Paedocypris progenetica, reaching 10.3 mm at the longest, all fish in this family are egg-layers and most do not guard their eggs, however, a few species build nests and/or guard the eggs. The bitterlings of subfamily Acheilognathinae are notable for depositing their eggs in bivalve molluscs, most cyprinids feed mainly on invertebrates and vegetation, probably due to the lack of teeth and stomach, but some species, like the asp, are predators that specialize in fish. Many species, such as the ide, and the common rudd, even small species, such as the moderlieschen, are opportunistic predators that will eat larvae of the common frog in artificial circumstances. For this reason, cyprinids are often introduced as a management tool to control various factors in the environment, such as aquatic vegetation. Cyprinids are highly important food fish, they are fished and farmed across Eurasia, in land-locked countries in particular, cyprinids are often the major species of fish eaten because they make the largest part of biomass in most water types except for fast-flowing rivers. In Eastern Europe, they are prepared with traditional methods. The prevalence of inexpensive frozen fish products made this less important now than it was in earlier times, nonetheless, in certain places, they remain popular for food, as well as recreational fishing, and have been deliberately stocked in ponds and lakes for centuries for this reason. Cyprinids are popular for angling especially for fishing and fishing for common carp because of its size
10.
Carassius
–
Carassius is a genus in the ray-finned fish family Cyprinidae. Many species in this genus are known as crucian carps. The most well known is the goldfish, which was bred from the Prussian carp and they have a Eurasian distribution, apparently originating further to the west than the typical carps, which include the common carp. Species of Carassius are not particularly close relatives of the typical carps of Cyprinus, Carassius auratus Carassius auratus argenteaphthalmus V. H. Nguyễn,2001 Carassius auratus auratus. Chinese, 黑鯽/黑鲫, pinyin, hēijì, Wade–Giles, hei 1 chi4, Ja, Ja, gengorō-buna cultivated taller body depth type. Ja, hera-buna Carassius gibelio Ja, Giberio-buna †Note that Fishbase listing of common names identification is not consistient with Japans Regional Red List, Fishbase for C. a. auratus lists kinbuna, and for C. a. buergeri both naga-buna and okin-buna. For the use of the European species, see Crucian carp, for convenience, it will be denoted the Chinese crucian. Although the Chinese crucian can be raised as pets, it is also farmed, despite being reputedly bony, the fish is easy to raise and relatively cheap, so are often deep-fried as part of a workers meal. Many extensive and luxurious preparations for this fish are used in Chinese cuisine, also, the Chinese crucian is used to make soup with tofu, which the Chinese believe to benefit women in the postpartum period. The several Japanese crucians are collectively called funa, the generic fish can be used in a preparation called kanro-ni, stewed in syrupy, soy sauce-flavored liquid till they glisten, a preserved dish similar to tsukudani. The specialty dish funazushi specifically calls for the use one species, hence, it would be misleading to say that any crucian carp may be used for this delicacy. However, due to diminishing resources, ersatz funazushi is now being made using substitute types such as C. cuvieri. The deep-bodied forms of C. cuvieri, called hera-buna, shaped rather like flatfishes, are caught by rod and tackle for sport, froese, Rainer, and Daniel Pauly, eds
11.
Binomial nomenclature
–
Such a name is called a binomial name, a binomen, binominal name or a scientific name, more informally it is also called a Latin name. The first part of the name identifies the genus to which the species belongs, for example, humans belong to the genus Homo and within this genus to the species Homo sapiens. The formal introduction of system of naming species is credited to Carl Linnaeus. But Gaspard Bauhin, in as early as 1623, had introduced in his book Pinax theatri botanici many names of genera that were adopted by Linnaeus. Although the general principles underlying binomial nomenclature are common to these two codes, there are differences, both in the terminology they use and in their precise rules. Similarly, both parts are italicized when a binomial name occurs in normal text, thus the binomial name of the annual phlox is now written as Phlox drummondii. In scientific works, the authority for a name is usually given, at least when it is first mentioned. In zoology Patella vulgata Linnaeus,1758, the original name given by Linnaeus was Fringilla domestica, the parentheses indicate that the species is now considered to belong in a different genus. The ICZN does not require that the name of the person who changed the genus be given, nor the date on which the change was made, in botany Amaranthus retroflexus L. – L. is the standard abbreviation used in botany for Linnaeus. – Linnaeus first named this bluebell species Scilla italica, Rothmaler transferred it to the genus Hyacinthoides, the ICN does not require that the dates of either publication be specified. Prior to the adoption of the binomial system of naming species. Together they formed a system of polynomial nomenclature and these names had two separate functions. First, to designate or label the species, and second, to be a diagnosis or description, such polynomial names may sometimes look like binomials, but are significantly different. For example, Gerards herbal describes various kinds of spiderwort, The first is called Phalangium ramosum, Branched Spiderwort, is aptly termed Phalangium Ephemerum Virginianum, Soon-Fading Spiderwort of Virginia. The Latin phrases are short descriptions, rather than identifying labels, the Bauhins, in particular Caspar Bauhin, took some important steps towards the binomial system, by pruning the Latin descriptions, in many cases to two words. The adoption by biologists of a system of binomial nomenclature is due to Swedish botanist and physician Carl von Linné. It was in his 1753 Species Plantarum that he first began using a one-word trivial name together with a generic name in a system of binomial nomenclature. This trivial name is what is now known as an epithet or specific name
12.
Carl Linnaeus
–
Carl Linnaeus, also known after his ennoblement as Carl von Linné, was a Swedish botanist, physician, and zoologist, who formalised the modern system of naming organisms called binomial nomenclature. He is known by the father of modern taxonomy. Many of his writings were in Latin, and his name is rendered in Latin as Carolus Linnæus, Linnaeus was born in the countryside of Småland, in southern Sweden. He received most of his education at Uppsala University. He lived abroad between 1735 and 1738, where he studied and also published a first edition of his Systema Naturae in the Netherlands and he then returned to Sweden, where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on journeys through Sweden to find and classify plants. In the 1750s and 1760s, he continued to collect and classify animals, plants, and minerals, at the time of his death, he was one of the most acclaimed scientists in Europe. The philosopher Jean-Jacques Rousseau sent him the message, Tell him I know no man on earth. The German writer Johann Wolfgang von Goethe wrote, With the exception of Shakespeare and Spinoza, Swedish author August Strindberg wrote, Linnaeus was in reality a poet who happened to become a naturalist. Among other compliments, Linnaeus has been called Princeps botanicorum, The Pliny of the North and he is also considered as one of the founders of modern ecology. In botany, the abbreviation used to indicate Linnaeus as the authority for species names is L. In older publications, sometimes the abbreviation Linn. is found, Linnæus was born in the village of Råshult in Småland, Sweden, on 23 May 1707. He was the first child of Nicolaus Ingemarsson and Christina Brodersonia and his siblings were Anna Maria Linnæa, Sofia Juliana Linnæa, Samuel Linnæus, and Emerentia Linnæa. One of a line of peasants and priests, Nils was an amateur botanist, a Lutheran minister. Christina was the daughter of the rector of Stenbrohult, Samuel Brodersonius, a year after Linnæus birth, his grandfather Samuel Brodersonius died, and his father Nils became the rector of Stenbrohult. The family moved into the rectory from the curates house, even in his early years, Linnæus seemed to have a liking for plants, flowers in particular. Whenever he was upset, he was given a flower, which calmed him. Nils spent much time in his garden and often showed flowers to Linnaeus, soon Linnæus was given his own patch of earth where he could grow plants
13.
10th edition of Systema Naturae
–
The 10th edition of Systema Naturae is a book written by Carl Linnaeus and published in two volumes in 1758 and 1759, which marks the starting point of zoological nomenclature. In it, Linnaeus introduced binomial nomenclature for animals, something he had already done for plants in his 1753 publication of Species Plantarum, before 1758, most biological catalogues had used polynomial names for the taxa included, including earlier editions of Systema Naturae. The first work to consistently apply binomial nomenclature across the kingdom was the 10th edition of Systema Naturae. Names published before that date are unavailable, even if they would otherwise satisfy the rules, during Linnaeus lifetime, Systema Naturae was under continuous revision. The Animal Kingdom, Animals enjoy sensation by means of an organization, animated by a medullary substance, perception by nerves. They have members for the different purposes of life, organs for their different senses and they all originate from an egg. Their external and internal structure, their anatomy, habits, instincts. The list has been broken down into the six classes Linnaeus described for animals, Mammalia, Aves, Amphibia, Pisces, Insecta. These classes were created by studying the internal anatomy, as seen in his key. Warm, red blood Viviparous, Mammalia Oviparous, Aves Heart with 1 auricle,1 ventricle, cold, red blood Lungs voluntary, Amphibia External gills, Pisces Heart with 1 auricle,0 ventricles. Linnaeus described mammals as, Animals that suckle their young by means of lactiferous teats, in external and internal structure they resemble man, most of them are quadrupeds, and with man, their natural enemy, inhabit the surface of the Earth. The largest, though fewest in number, inhabit the ocean and they are areal, vocal, swift and light, and destitute of external ears, lips, teeth, scrotum, womb, bladder, epiglottis, corpus callosum and its arch, and diaphragm. They breathe by means of gills, which are united by a bony arch, swim by means of radiate fins. Many of them are without a head, and most of them without feet. They are principally distinguished by their tentacles, by the Ancients they were not improperly called imperfect animals, as being destitute of ears, nose, head, eyes and legs, and are therefore totally distinct from Insects. In addition to repeating the species he had listed in his Species Plantarum. The species from Species Plantarum were numbered sequentially, while the new species were labelled with letters, new plant species described in the 10th edition of Systema Naturae include, The original 1758 Systema Naturae Linnaeus 1758 Classification of Animals on the Taxonomicon
14.
Synonym (taxonomy)
–
For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies. This name is no longer in use, it is now a synonym of the current scientific name which is Picea abies, unlike synonyms in other contexts, in taxonomy a synonym is not interchangeable with the name of which it is a synonym. In taxonomy, synonyms are not equals, but have a different status, for any taxon with a particular circumscription, position, and rank, only one scientific name is considered to be the correct one at any given time. A synonym cannot exist in isolation, it is always an alternative to a different scientific name, given that the correct name of a taxon depends on the taxonomic viewpoint used a name that is one taxonomists synonym may be another taxonomists correct name. Synonyms may arise whenever the same taxon is described and named more than once, independently. They may also arise when existing taxa are changed, as when two taxa are joined to one, a species is moved to a different genus. To the general user of scientific names, in such as agriculture, horticulture, ecology, general science. A synonym is a name that was used as the correct scientific name but which has been displaced by another scientific name. Thus Oxford Dictionaries Online defines the term as a name which has the same application as another. In handbooks and general texts, it is useful to have mentioned as such after the current scientific name. Synonyms used in this way may not always meet the strict definitions of the synonym in the formal rules of nomenclature which govern scientific names. Changes of scientific name have two causes, they may be taxonomic or nomenclatural, a name change may be caused by changes in the circumscription, position or rank of a taxon, representing a change in taxonomic, scientific insight. A name change may be due to purely nomenclatural reasons, that is, based on the rules of nomenclature, the earliest such name is called the senior synonym, while the later name is the junior synonym. One basic principle of zoological nomenclature is that the earliest correctly published name, synonyms are important because if the earliest name cannot be used, then the next available junior synonym must be used for the taxon. Objective synonyms refer to taxa with the type and same rank. For example, John Edward Gray published the name Antilocapra anteflexa in 1855 for a species of pronghorn, however, it is now commonly accepted that his specimen was an unusual individual of the species Antilocapra americana published by George Ord in 1815. Ords name thus takes precedence, with Antilocapra anteflexa being a subjective synonym. Objective synonyms are common at the level of genera, because for various reasons two genera may contain the type species, these are objective synonyms
15.
Freshwater fish
–
Freshwater fish are those that spend some or all of their lives in fresh water, such as rivers and lakes, with a salinity of less than 0. 05%. These environments differ from marine conditions in ways, the most obvious being the difference in levels of salinity. To survive fresh water, the fish need a range of physiological adaptations,41. 24% of all known species of fish are found in fresh water. This is primarily due to the rapid speciation that the scattered habitats make possible, when dealing with ponds and lakes, one might use the same basic models of speciation as when studying island biogeography. Freshwater fish differ physiologically from salt water fish in several respects and their gills must be able to diffuse dissolved gasses while keeping the salts in the body fluids inside. Their scales reduce water diffusion through the skin, freshwater fish that have lost too many scales will die and they also have well developed kidneys to reclaim salts from body fluids before excretion. Many species of fish do reproduce in freshwater, but spend most of their lives in the sea. These are known as fish, and include, for instance, salmon, trout. Some other kinds of fish are, on the contrary, born in salt water and these are known as catadromous fish. Many species solve this problem by associating different habitats with different stages of life, both eels, anadromous salmoniform fish and the sea lamprey have different tolerances in salinity in different stages of their lives. Freshwater fish species are classified by the water temperature in which they survive. The water temperature affects the amount of oxygen available as water contains more oxygen than warm water. Coldwater fish species survive in the coldest temperatures, preferring a water temperature of 50 °F to 60 °F degrees. In North America, air temperatures result in sufficiently cold water temperatures are found in the northern United States, Canada. Common coldwater fish include trout, rainbow trout, and brown trout. Common warmwater fish include bass, bluegill, catfish. Coolwater fish species prefer water temperature between the coldwater and warmwater species, around 60 °F to 80 °F and they are found throughout North America except for the southern portions of the United States. The number of species and subspecies to become endangered has risen from 40 to 61
16.
Family (biology)
–
In biological classification, family is one of the eight major taxonomic ranks, it is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks above the rank of genus. In vernacular usage, a family may be named one of its common members, for example, walnuts and hickory trees belong to the family Juglandaceae. What does or does not belong to a family—or whether a family should be recognized at all—are proposed and determined by practicing taxonomists. There are no rules for describing or recognizing a family. Taxonomists often take different positions about descriptions of taxa, and there may be no broad consensus across the community for some time. Some described taxa are accepted broadly and quickly, but others only rarely, if at all, the naming of families is codified by various international codes. In zoological nomenclature, the names of animals end with the suffix -idae. The concept of rank at time was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera. Carolus Linnaeus used the word familia in his Philosophia botanica to denote groups of plants, trees, herbs, ferns, palms. He used this term only in the section of the book. In zoology, the family as an intermediate between order and genus was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes. He used families in some but not in all his orders of insects, families can be used for evolutionary, palaeontological and generic studies because they are more stable than lower taxonomic levels such as genera and species
17.
Order (biology)
–
In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, an immediately higher rank, superorder, may be added directly above order, while suborder would be a lower rank. A taxonomic unit, a taxon, in that rank, in that case the plural is orders. Example, The Juglans and Hickory trees belong to the family Juglandaceae, what does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no agreement, with different taxonomists each taking a different position. There are no rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognised only rarely, for some groups of organisms, consistent suffixes are used to denote that the rank is an order. The Latin suffix -formes meaning having the form of is used for the name of orders of birds and fishes. The suffix -ales is for the name of orders of plants, fungi, for some clades covered by the International Code of Zoological Nomenclature, a number of additional classifications are sometimes used, although not all of these are officially recognised. In their 1997 classification of mammals, McKenna and Bell used two levels between superorder and order, grandorder and mirorder. Michael Novacek inserted them at the same position, michael Benton inserted them between superorder and magnorder instead. This position was adopted by Systema Naturae 2000 and others, in botany, the ranks of subclass and suborder are secondary ranks pre-defined as respectively above and below the rank of order. Any number of further ranks can be used as long as they are clearly defined, the superorder rank is commonly used, with the ending -anae that was initiated by Armen Takhtajans publications from 1966 onwards. Carl Linnaeus was the first to apply it consistently to the division of all three kingdoms of nature in his Systema Naturae, for plants, Linnaeus orders in the Systema Naturae and the Species Plantarum were strictly artificial, introduced to subdivide the artificial classes into more comprehensible smaller groups. In French botanical publications, from Michel Adansons Familles naturelles des plantes and until the end of the 19th century, some of the plant families still retain the names of Linnaean natural orders or even the names of pre-Linnaean natural groups recognised by Linnaeus as orders in his natural classification. Such names are known as family names. In zoology, the Linnaean orders were used more consistently and that is, the orders in the zoology part of the Systema Naturae refer to natural groups. Some of his names are still in use
18.
Carp
–
Carp are various species of oily freshwater fish from the family Cyprinidae, a very large group of fish native to Europe and Asia. The cypriniformes are traditionally grouped with the Characiformes, Siluriformes, and Gymnotiformes to create the superorder Ostariophysi, the third anterior-most pair of ribs is in contact with the extension of the labyrinth and the posterior with the swim bladder. Most cypriniformes have scales and teeth on the pharyngeal bones which may be modified in relation to the diet. Tribolodon is the only cyprinid genus which tolerates salt water, several species move into brackish water but return to fresh water to spawn. All of the other cypriniformes live in waters and have a wide geographical range. Some consider all cyprinid fishes carp, and the family Cyprinidae itself is known as the carp family. Carp have long been an important food fish to humans, several species such as the various goldfish breeds and the domesticated common carp variety known as koi have been popular ornamental fishes. As a result, carp have been introduced to various locations, several species of carp are listed as invasive species by the U. S. Department of Agriculture, and, worldwide, large sums of money are spent on carp control. At least some species of carp are able to survive for months with no oxygen by metabolizing glycogen to form ethanol. Carp are variable in terms of angling value, in Europe, even when not fished for food, they are eagerly sought by anglers, being considered highly prized coarse fish that are difficult to hook. The UK has a thriving carp angling market, in the United States, carp are also classified as a rough fish, as well as damaging to naturalized exotic species, but with sporting qualities. Many states departments of natural resources are beginning to view the carp as a fish instead of a maligned pest. Various species of carp have been domesticated and reared as food fish across Europe and these various species appear to have been domesticated independently, as the various domesticated carp species are native to different parts of Eurasia. Aquaculture has been pursued in China for at least 2,400 years, a tract by Fan Li in the fifth century BC details many of the ways carp were raised in ponds. The common carp, Cyprinus carpio, is originally from Central Europe, several carp species were domesticated in East Asia. Carp that are originally from South Asia, for example catla, rohu and their hardiness and adaptability have allowed domesticated species to be propagated all around the world. Although the carp was an important aquatic food item, as fish species have become readily available for the table. Demand has declined, partly due to the appearance of more desirable fish such as trout and salmon through intensive farming
19.
Prussian carp
–
The Prussian carp, silver Prussian carp or Gibel carp, is a member of the family Cyprinidae, which includes many other fish, such as the common carp, and the smaller minnows. It is a medium-sized cyprinid, and does not exceed a weight of 6.6 pounds and they are usually silver, although other color variations exist. They are omnivorous and feed on plankton, invertebrates, plant material, originally from Asia, they have been introduced to and are now inhabiting lakes, ponds, and slow-moving rivers throughout Europe, North America, and Asia. The Prussian carp is a deep-bodied, robust fish which resembles the Crucian carp and its scales are larger than those of the Crucian carp, and it typically has 27 to 32 scales along the lateral line, whereas the Crucian carp usually has between 31 and 35. The species is silvery, sometimes with a faint golden tinge, the Prussian carps tail is more deeply forked than that of the Crucian carp. Goldfish were originally developed from domesticated Prussian carp in China over 1,000 years ago, although some sources claim that crucian carp are the wild version of the goldfish, recent research has found that the wild form of the goldfish is actually the Prussian carp. The wild form of the goldfish often has a grey/greenish color, juvenile crucian carp have a black spot on the base of the tail which disappears with age. In C. auratus, this spot is never present. C. auratus fish have fewer than 31 scales along the lateral line, C. carassius has 28 to 29 fine denticles on the posterior edge of the last unbranched spiny ray of the dorsal fin, while C. auratus has 10 to 11 irregular denticles
20.
Crucian carp
–
The crucian carp is a medium-sized member of the common carp family Cyprinidae. It occurs widely in northern European regions and its habitat includes lakes, ponds, and slow-moving rivers. It has been established that the fish is native to England, the crucian is a medium-sized cyprinid, typically 15 cm in body length, and rarely exceeds in weight over 1.5 kilograms. But a maximum length of 64.0 cm is reported for a male. One distinguishing characteristic is a rounded fin, as opposed to goldfish hybrids which have concave fins. The variation in shape of a crucian carp can be very high, the crucian carp is also the type species for the genus, which has led to confusion in the taxonomy of species native to East Asia. There are reports of hybridisation between the crucian and domestic or feral goldfish, which has been verified by production of hybrids in laboratory conditions. Carassius species exhibit some remarkable physiological adaptations to their environment, experimentally the fish have been maintained under anoxic conditions for 140 days. Anoxia can be tolerated longest in the coldest water, even down to 0 °C, alcohol production occurs mainly in the muscle tissues, but also in the liver, where the process is thought to have originated. Similarly goldfish can produce alcohol in muscle tissues, but to a more limited extent. In turn the fish excretes the ethanol into the water rather than accumulating it to toxic levels in the tissues. Excretion of lactate in significant quantities is not a common nor a desirable metabolic facility and this metabolic expedient avoids the fatal accumulation of acid end-products of anaerobic glycolysis. In Britain, leisurely or competitive catching of fish by rod. The British rod-caught record for largest crucian is four pounds, nine ounces, landed by Martin Bowler in 2003, tied by Joshua Blavins in 2011. There have been various bids for a breakage of this record since, in the Netherlands, a typical crucian specimen of 54 cm, weighing 3 kg has been caught and photographed. Many sources state that the goldfish is a breed of crucian carp taken from the wild. Since crucian carp is the name of the genus this is not strictly wrong, genetic research has shown that the goldfish actually derives from the Prussian carp Carassius gibelio. Aside from confusion in nomenclature, there is the issue of distinguishing true crucian carp from goldfish hybrids in
21.
East Asia
–
East Asia is the eastern subregion of the Asian continent, which can be defined in either geographical or ethno-cultural terms. Geographically and geopolitically, it includes China, Taiwan, Mongolia, Korea and Japan, it covers about 12,000,000 km2, or about 28% of the Asian continent, the East Asian people comprise more than 1.5 billion people. About 38% of the population of Asia and 22%, or over one fifth, the overall population density of the region is 133 inhabitants per square kilometre, about three times the world average of 45/km2. Historically, societies in East Asia have been part of the Chinese cultural sphere, major religions include Buddhism, Confucianism or Neo-Confucianism, Taoism, Chinese folk religion in China and Taiwan, Shinto in Japan, Korean shamanism in Korea. Shamanism is also prevalent among Mongolians and other populations of northern East Asia. The Chinese calendar is the root from which many other East Asian calendars are derived, Chinese Dynasties dominated the region in matters of culture, trade, and exploration as well as militarily for a very long time. There are records of tributes sent overseas from the kingdoms of Korea. There were also considerable levels of cultural and religious exchange between the Chinese and other regional Dynasties and Kingdoms, as connections began to strengthen with the Western world, Chinas power began to diminish. Around the same time, Japan solidified itself as a nation state, throughout World War II, Korea, Taiwan, much of eastern China, Hong Kong, and Vietnam all fell under Japanese control. Culturally, China, Japan, Korea, Taiwan and Vietnam are commonly seen as being encompassed by cultural East Asia, there are mixed debates around the world whether these countries or regions should be considered in East Asia or not. Vietnam Siberia in Russia Sovereignty issues exist over some territories in the South China Sea, however, in this context, the term Far East is often more appropriate which covers ASEAN countries and the countries in East Asia. However, being a Eurocentric term, Far East describes the geographical position in relation to Europe rather than its location within Asia. Alternatively, the term Asia Pacific Region is often used in describing East Asia and this usage, which is seen in economic and diplomatic discussions, is at odds with the historical meanings of both East Asia and Northeast Asia. The Council on Foreign Relations defines Northeast Asia as Japan and Korea, the military and economic superpower of China became the largest economy in the world in 2014, surpassing the United States of America. Currently in East Asia, trading systems are open, and zero or low duties on imports of consumer and capital goods etc. have considerably helped stimulate cost-efficiency. Free and flexible labor and other markets are important factors making for high levels of business-economic performance. East Asian populations have demonstrated highly positive work ethics, there are relatively large and fast-growing markets for consumer goods and services of all kinds. The culture of East Asia has been influenced by the civilisation of China, East Asia, as well as Vietnam, share a Confucian ethical philosophy, Buddhism, political and legal structures, and historically a common writing system
22.
History of China
–
Written records of the history of China can be found from as early as 1500 BC under the Shang dynasty. Ancient historical texts such as the Records of the Grand Historian and the Bamboo Annals describe a Xia dynasty, with thousands of years of continuous history, China is one of the worlds oldest civilizations, and is regarded as one of the cradles of civilization. Much of Chinese culture, literature and philosophy developed during the Zhou dynasty. This is one of multiple periods of failed statehood in Chinese history, between eras of multiple kingdoms and warlordism, Chinese dynasties have ruled parts or all of China, in some eras control stretched as far as Xinjiang and Tibet, as at present. In 221 BC Qin Shi Huang united the warring kingdoms and created for himself the title of emperor of the Qin dynasty. Successive dynasties developed bureaucratic systems that enabled the emperor to control vast territories directly, in the 21 centuries from 206 BC until AD1912, routine administrative tasks were handled by a special elite, the Scholar-officials. Young men were selected through difficult examinations and were well-versed in calligraphy and philosophy. What is now China was inhabited by Homo erectus more than a million years ago, recent study shows that the stone tools found at Xiaochangliang site are magnetostratigraphically dated to 1.36 million years ago. The archaeological site of Xihoudu in Shanxi Province is the earliest recorded use of fire by Homo erectus, the excavations at Yuanmou and later Lantian show early habitation. Perhaps the most famous specimen of Homo erectus found in China is the so-called Peking Man discovered in 1923–27, fossilised teeth of Homo sapiens dating to 125, 000–80,000 BC have been discovered in Fuyan Cave in Dao County in Hunan. The Neolithic age in China can be traced back to about 10,000 BC, Early evidence for proto-Chinese millet agriculture is radiocarbon-dated to about 7000 BC. The earliest evidence of cultivated rice, found by the Yangtze River, is carbon-dated to 8,000 years ago, farming gave rise to the Jiahu culture. At Damaidi in Ningxia,3,172 cliff carvings dating to 6000–5000 BC have been discovered, featuring 8,453 individual characters such as the sun, moon, stars, gods and these pictographs are reputed to be similar to the earliest characters confirmed to be written Chinese. Chinese proto-writing existed in Jiahu around 7000 BC, Dadiwan from 5800 BC to 5400 BC, Damaidi around 6000 BC, some scholars have suggested that Jiahu symbols were the earliest Chinese writing system. With agriculture came increased population, the ability to store and redistribute crops, Later, Yangshao culture was superseded by the Longshan culture, which was also centered on the Yellow River from about 3000 BC to 2000 BC. Bronze artifacts have been found at the Majiayao culture site, The Bronze Age is also represented at the Lower Xiajiadian culture site in northeast China. Sanxingdui located in what is now Sichuan province is believed to be the site of a ancient city. The site was first discovered in 1929 and then re-discovered in 1986, Chinese archaeologists have identified the Sanxingdui culture to be part of the ancient kingdom of Shu, linking the artifacts found at the site to its early legendary kings
23.
Song dynasty
–
The Song dynasty was an era of Chinese history that began in 960 and continued until 1279. It succeeded the Five Dynasties and Ten Kingdoms period, coincided with the Liao and Western Xia dynasties and it was the first government in world history to issue banknotes or true paper money nationally and the first Chinese government to establish a permanent standing navy. This dynasty also saw the first known use of gunpowder, as well as the first discernment of true north using a compass, the Song dynasty is divided into two distinct periods, Northern and Southern. During the Northern Song, the Song capital was in the city of Bianjing. The Southern Song refers to the period after the Song lost control of its half to the Jurchen Jin dynasty in the Jin–Song Wars. During this time, the Song court retreated south of the Yangtze, the Southern Song dynasty considerably bolstered its naval strength to defend its waters and land borders and to conduct maritime missions abroad. To repel the Jin, and later the Mongols, the Song developed revolutionary new military technology augmented by the use of gunpowder, in 1234, the Jin dynasty was conquered by the Mongols, who took control of northern China, maintaining uneasy relations with the Southern Song. Möngke Khan, the fourth Great Khan of the Mongol Empire and his younger brother Kublai Khan was proclaimed the new Great Khan, though his claim was only partially recognized by the Mongols in the west. In 1271, Kublai Khan was proclaimed the Emperor of China, after two decades of sporadic warfare, Kublai Khans armies conquered the Song dynasty in 1279. The Mongol invasion led to a reunification under the Yuan dynasty, the population of China doubled in size during the 10th and 11th centuries. The Northern Song census recorded a population of roughly 50 million, much like the Han and this data is found in the Standard Histories. However, it is estimated that the Northern Song had a population of some 100 million people and this dramatic increase of population fomented an economic revolution in pre-modern China. The expansion of the population, growth of cities, and the emergence of a national economy led to the withdrawal of the central government from direct involvement in economic affairs. The lower gentry assumed a role in grassroots administration and local affairs. Appointed officials in county and provincial centers relied upon the gentry for their services, sponsorship. Social life during the Song was vibrant, citizens gathered to view and trade precious artworks, the populace intermingled at public festivals and private clubs, and cities had lively entertainment quarters. The spread of literature and knowledge was enhanced by the expansion of woodblock printing. Technology, science, philosophy, mathematics, and engineering flourished over the course of the Song, although the institution of the civil service examinations had existed since the Sui dynasty, it became much more prominent in the Song period
24.
Coldwater fish
–
Coldwater fish, in the context of aquariums, refers to fish species that prefer cooler water temperatures than tropical fish, typically below 20 °C. Some examples are koi and goldfish and these species tend to grow more slowly and live longer than fish that live in warmer waters, and are generally felt to be easier to keep. Coldwater fish are fish such as goldfish, koi, and other members of the family that are able to survive in cold water temperatures. When kept in an aquarium, they do not require a heater and are quite comfortable at around 60 °F. These fish are also desirable choices for outdoor ponds and can stand temperatures down to 10 °C, note, The above contains a mix of true coldwater fish and sub-tropical fish that can survive and thrive at room temperature which ranges from 15 °C and to 30 °C. The term is used to refer to fish species in the wild
25.
Asian carp
–
Several species of heavy-bodied cyprinid fishes are collectively known in the United States as Asian carp. Cyprinids from the Indian subcontinent, for example, catla and mrigal are not included in this classification, largescale silver carp, a more southern species, is native to Vietnam and is cultivated there. Grass, silver, bighead, and black carp are known as the Four Domesticated Fish in China and are the most important freshwater fish species for food, bighead and silver carp are the most important fish, worldwide, in terms of total aquaculture production. Common carp and crucian carp are also common foodfishes in China, goldfish, though, are cultivated mainly as pet fish. Common carp are native to both Eastern Europe and Western Asia, so they are called a Eurasian carp. A long tradition of Asian carp exists in Chinese culture and literature, at the Yellow River at Henan is a waterfall called the Dragon Gate. It is said that if certain carp called yulong can climb the cataract, every year in the third month of spring, they swim up from the sea and gather in vast numbers in the pool at the foot of the falls. It used to be said that only 71 could make the climb in any year, when the first succeeded, then the rains would begin to fall. This Dragon Gate was said to have created after the flood by the god-emperor Yu. It was so famous that throughout China was a common saying, Henan is not the only place where this happens. Many other waterfalls in China also have the name Dragon Gate, other famous Dragon Gates are on the Wei River where it passes through the Lung Sheu Mountains and at Tsin in Shanxi Province. It is therefore an idiom used to encourage students or children to achieve success through hard work. This symbolic image, as well as the image of itself, has been one of the most popular themes in Chinese paintings. The fish is colored in gold or pink, shimmering with an unmistakably auspicious tone. Yuquan, one of the scenic spots in Hangzhou, has a large fish pond alive with hundreds of carp of various colors. A three-character inscription, Yu-Le-Guo, meaning fish’s paradise, is set above one end of the pond in the calligraphy of a famous gentry-scholar of the late Ming Dynasty named Dong Qichang, many tourists feed the fish with bread crumbs. Among the various kinds of carp, the carp is least expensive in China. The grass carp is still a main delicacy in Hangzhou cuisine, the fish is normally served with a vinegar-based sweet-and-sour sauce
26.
Aquaculture
–
Aquaculture, also known as aquafarming, is the farming of fish, crustaceans, molluscs, aquatic plants, algae, and other aquatic organisms. Aquaculture involves cultivating freshwater and saltwater populations under controlled conditions, and can be contrasted with commercial fishing, mariculture refers to aquaculture practiced in marine environments and in underwater habitats. According to the FAO, aquaculture Farming implies some form of intervention in the process to enhance production, such as regular stocking, feeding, protection from predators. Farming also implies individual or corporate ownership of the stock being cultivated, further, in current aquaculture practice, products from several pounds of wild fish are used to produce one pound of a piscivorous fish like salmon. Particular kinds of aquaculture include fish farming, shrimp farming, oyster farming, mariculture, algaculture, particular methods include aquaponics and integrated multi-trophic aquaculture, both of which integrate fish farming and plant farming. The indigenous Gunditjmara people in Victoria, Australia, may have raised eels as early as 6000 BC, Aquaculture was operating in China circa 2500 BC. When the waters subsided after river floods, some fish, mainly carp, were trapped in lakes, early aquaculturists fed their brood using nymphs and silkworm feces, and ate them. A fortunate genetic mutation of carp led to the emergence of goldfish during the Tang dynasty, japanese cultivated seaweed by providing bamboo poles and, later, nets and oyster shells to serve as anchoring surfaces for spores. Romans bred fish in ponds and farmed oysters in coastal lagoons before 100 CE, in central Europe, early Christian monasteries adopted Roman aquacultural practices. Aquaculture spread in Europe during the Middle Ages since away from the seacoasts, improvements in transportation during the 19th century made fresh fish easily available and inexpensive, even in inland areas, making aquaculture less popular. The 15th-century fishponds of the Trebon Basin in the Czech Republic are maintained as a UNESCO World Heritage Site, a remarkable example is a fish pond dating from at least 1,000 years ago, at Alekoko. Legend says that it was constructed by the mythical Menehune dwarf people, in first half of 18th century, German Stephan Ludwig Jacobi experimented with external fertilization of brown trouts and salmon. He wrote an article Von der künstlichen Erzeugung der Forellen und Lachse, by the latter decades of the 18th century, oyster farming had begun in estuaries along the Atlantic Coast of North America. The word aquaculture appeared in an 1855 newspaper article in reference to the harvesting of ice, in 1859, Stephen Ainsworth of West Bloomfield, New York, began experiments with brook trout. By 1864, Seth Green had established a commercial fish-hatching operation at Caledonia Springs, near Rochester, by 1866, with the involvement of Dr. W. W. Fletcher of Concord, Massachusetts, artificial fish hatcheries were under way in both Canada and the United States. When the Dildo Island fish hatchery opened in Newfoundland in 1889, the word aquaculture was used in descriptions of the hatcheries experiments with cod and lobster in 1890. By the 1920s, the American Fish Culture Company of Carolina, Rhode Island, during the 1940s, they had perfected the method of manipulating the day and night cycle of fish so that they could be artificially spawned year around. Californians harvested wild kelp and attempted to supply around 1900
27.
Mutation
–
In biology, a mutation is the permanent alteration of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA or other genetic elements. Mutations may also result from insertion or deletion of segments of DNA due to mobile genetic elements, mutations may or may not produce discernible changes in the observable characteristics of an organism. Mutations play a part in normal and abnormal biological processes including, evolution, cancer, and the development of the immune system. The genomes of RNA viruses are based on RNA rather than DNA, the RNA viral genome can be double stranded or single stranded. In some of these viruses replication occurs quickly and there are no mechanisms to check the genome for accuracy and this error-prone process often results in mutations. Mutation can result in different types of change in sequences. Mutations in genes can either have no effect, alter the product of a gene, mutations can also occur in nongenic regions. Mutations can involve the duplication of large sections of DNA, usually through genetic recombination and these duplications are a major source of raw material for evolving new genes, with tens to hundreds of genes duplicated in animal genomes every million years. Most genes belong to larger families of shared ancestry, known as homology. Here, protein domains act as modules, each with a particular and independent function, that can be mixed together to produce genes encoding new proteins with novel properties. For example, the eye uses four genes to make structures that sense light. Another advantage of duplicating a gene is that this increases engineering redundancy, other types of mutation occasionally create new genes from previously noncoding DNA. Changes in chromosome number may involve even larger mutations, where segments of the DNA within chromosomes break and then rearrange. For example, in the Homininae, two fused to produce human chromosome 2, this fusion did not occur in the lineage of the other apes. Sequences of DNA that can move about the genome, such as transposons, make up a fraction of the genetic material of plants and animals. For example, more than a million copies of the Alu sequence are present in the genome. Another effect of these mobile DNA sequences is that when they move within a genome, they can mutate or delete existing genes, nonlethal mutations accumulate within the gene pool and increase the amount of genetic variation. The abundance of some changes within the gene pool can be reduced by natural selection, while other more favorable mutations may accumulate
28.
Tang dynasty
–
The Tang dynasty was an imperial dynasty of China preceded by the Sui dynasty and followed by the Five Dynasties and Ten Kingdoms period. It is generally regarded as a point in Chinese civilization. Its territory, acquired through the campaigns of its early rulers, rivaled that of the Han dynasty. The dynasty was founded by the Lǐ family, who seized power during the decline, the dynasty was briefly interrupted when Empress Wu Zetian seized the throne, proclaiming the Second Zhou dynasty and becoming the only Chinese empress regnant. In two censuses of the 7th and 8th centuries, the Tang records estimated the population by number of registered households at about 50 million people. Various kingdoms and states paid tribute to the Tang court, while the Tang also conquered or subdued several regions which it controlled through a protectorate system. Besides political hegemony, the Tang also exerted a powerful influence over neighboring states such as those in Korea, Japan. Like the previous Sui dynasty, the Tang dynasty maintained a service system by recruiting scholar-officials through standardized examinations and recommendations to office. This civil order was undermined by the rise of military governors known as jiedushi during the 9th century. Chinese culture flourished and further matured during the Tang era, it is considered the greatest age for Chinese poetry. Two of Chinas most famous poets, Li Bai and Du Fu, belonged to this age, as did many famous painters such as Han Gan, Zhang Xuan, there was a rich variety of historical literature compiled by scholars, as well as encyclopedias and geographical works. The adoption of the title Tängri Qaghan by the Tang Emperor Taizong in addition to his title as emperor was eastern Asias first simultaneous kingship, there were many notable innovations during the Tang, including the development of woodblock printing. Buddhism became an influence in Chinese culture, with native Chinese sects gaining prominence. However, Buddhism would later be persecuted by the state, subsequently declining in influence, although the dynasty and central government were in decline by the 9th century, art and culture continued to flourish. This family was known as the Longxi Li lineage, which includes the Tang poet Li Bai, the Tang Emperors also had Xianbei maternal ancestry, from Emperor Gaozu of Tangs Xianbei mother Duchess Dugu. He had prestige and military experience, and was a first cousin of Emperor Yang of Sui, Li Yuan rose in rebellion in 617, along with his son and his equally militant daughter Princess Pingyang, who raised and commanded her own troops. In winter 617, Li Yuan occupied Changan, relegated Emperor Yang to the position of Taishang Huang or retired emperor, and acted as regent to the puppet child-emperor, Emperor Gong of Sui. On the news of Emperor Yangs murder by General Yuwen Huaji on June 18,618, Li Yuan declared himself the emperor of a new dynasty, the Tang
29.
Water garden
–
Water gardens, also known as aquatic gardens, are a type of water feature. They can be defined as any interior or exterior landscape or architectural element whose primary purpose is to house, display, the primary focus is on plants, but they will sometimes also house ornamental fish, in which case the feature will be a fish pond. Water gardening is gardening that is concerned with growing plants adapted to pools, although water gardens can be almost any size or depth, they are typically small and relatively shallow, generally less than twenty inches in depth. This is because most aquatic plants are sensitive and require a specific water depth in order to thrive. The particular species inhabiting each water garden will ultimately determine the surface area. When the aquatic flora and fauna are balanced, an ecosystem is created that will support sustainable water quality and clarity. Water gardens, and water features in general, have been a part of public and private gardens since ancient Persian gardens, for instance, the Nanfang Caomu Zhuang records cultivating Chinese spinach on floating gardens. Water features have been present and well represented in every era and in culture that has included gardens in their landscape. Historically, water features were used to plant and fish production both for food purposes and for ornamental aesthetics. In Italy several royal houses constructed large water gardens incorporating mechanical devices in water settings, the best-known is the Villa dEste at Tivoli, constructed in 1550 AD. A hill cascaded with many fountains and grottoes, some with water-driven figures that moved or spouted water, on a constructed stream, placing rocks in the path of the water makes small patterns, rapids and waterfalls. The rocks disrupt the waterflow, causing splashing and bubbles that can make pleasant sounds and micro-habitats for plants, fish, well-placed rocks can create splashing water that adds oxygen to prevent hypoxia, the more bubbles, the more dissolved oxygen in the water. Water garden plants are divided into three categories, submerged, marginal, and floating. Submerged plants are those that live almost completely under the water and these plants are placed in a pond or container usually 1–2 ft below the water surface. Some of these plants are called oxygenators because they create oxygen for the fish live in a pond. Examples of submerged plants are, Water lily Hornwort Marginal plants are those that live with their roots under the water and these are usually placed so that the top of the pot is at or barely below the water level. In water gardening, these are used as a provider of shade to reduce algae growth in a pond. These are often extremely fast growing/multiplying, algae are found in almost all ponds
30.
Emperor
–
An emperor is a monarch, usually the sovereign ruler of an empire or another type of imperial realm. Empress, the equivalent, may indicate an emperors wife, mother. Emperors are generally recognized to be of an honour and rank than kings. The Emperor of Japan is the currently reigning monarch whose title is translated into English as Emperor. Both kings and emperors are monarchs, but emperor and empress are considered the higher monarchical titles. In as much as there is a definition of emperor, it is that an emperor has no relations implying the superiority of any other ruler. Thus a king might be obliged to pay tribute to another ruler, or be restrained in his actions in some unequal fashion, although initially ruling much of Central Europe and northern Italy, by the 19th century the Emperor exercised little power beyond the German speaking states. In Eastern Europe the rulers of the Russian Empire also used translatio imperii to wield authority as successors to the Eastern Roman Empire. Their title of Emperor was officially recognised by the Holy Roman Emperor in 1514, in practice the Russian Emperors are often known by their Russian-language title Tsar, which may also used to refer to rulers equivalent to a king. Historians have liberally used emperor and empire anachronistically and out of its Roman and European context to any large state from the past or the present. Such pre-Roman titles as Great King or King of Kings, used by the Kings of Persia, however such empires did not need to be headed by an emperor. Empire became identified instead with vast territorial holdings rather than the title of its ruler by the mid-18th century, outside the European context, emperor was the translation given to holders of titles who were accorded the same precedence as European emperors in diplomatic terms. In reciprocity, these rulers might accredit equal titles in their languages to their European peers. Through centuries of international convention, this has become the dominant rule to identifying an emperor in the modern era, also the name of the position split in several branches of Western tradition, see below. Later new symbols of worldly and/or spiritual power, like the orb, rules for indicating successors also varied, there was a tendency towards male inheritance of the supreme office, but as well election by noblemen, as ruling empresses are known. Ruling monarchs could additionally steer the succession by adoption, as occurred in the two first centuries of Imperial Rome. Of course, intrigue, murder and military force could also mingle in for appointing successors, probably the epoch best known for this part of the imperial tradition is Romes third century rule. When Republican Rome turned into a de facto monarchy in the half of the 1st century BC
31.
Shades of yellow
–
Varieties of the color yellow may differ in hue, chroma or lightness, or in two or three of these qualities. Variations in value are also called tints and shades, a tint being a yellow or other hue mixed with white, a large selection of these various colors is shown below. Displayed at right is the web color light yellow, displayed at right is the web color cream, a pale tint of yellow. Displayed at right is the web color lemon chiffon Lemon chiffon is a color that is reminiscent of the color of lemon chiffon cake. The color box at right shows the most intense yellow representable in 8-bit RGB color model and this color is also called color wheel yellow. It is at precisely 60 degrees on the HSV color wheel, process yellow, also known as canary yellow, is one of the three colors typically used as subtractive primary colors, along with magenta and cyan. Process yellow is not an RGB color, and in the CMYK color model there is no fixed conversion from CMYK primaries to RGB, different formulations are used for printers ink, so there can be variations in the printed color that is pure yellow ink. The first recorded use of yellow as a color name in English was in 1789. The color defined as yellow in the NCS or Natural Color System is shown at right, the Natural Color System is a color system based on the four unique hues or psychological primary colors red, yellow, green, and blue. The NCS is based on the opponent process theory of vision, the “Natural Color System” is widely used in Scandinavia. The color defined as yellow in the Munsell color system is shown at right, in order for all the colors to be spaced uniformly, it was found necessary to use a color wheel with five primary colors—red, yellow, green, blue, and purple. The Munsell colors displayed are only approximate as they have adjusted to fit into the sRGB gamut. The color that is called yellow in Pantone is displayed at right, the source of this color is the Pantone Textile Paper eXtended color list, color #C, EC, M, PC, U, or CP—Yellow. The color that is called yellow in Crayola crayons is displayed at right, Yellow was one of the original Crayola colors formulated in 1903. The color unmellow yellow is shown at right, the color unmellow yellow was formulated by Crayola in 1990. The color unmellow yellow is a fluorescent yellow to Laser Lemon. In crayons, the color may look a little bit orange-ish, the color is supposed to be fluorescent, but there is no mechanism to display fluorescence on a flat computer screen. Lemon is a color somewhat resembling yellow and named after the fruit, the color lemon is a representation of the color of the outer skin of a lemon
32.
Ming dynasty
–
The Ming dynasty was the ruling dynasty of China – then known as the Empire of the Great Ming – for 276 years following the collapse of the Mongol-led Yuan dynasty. The Ming, described by some as one of the greatest eras of orderly government, although the primary capital of Beijing fell in 1644 to a rebellion led by Li Zicheng, regimes loyal to the Ming throne – collectively called the Southern Ming – survived until 1683. He rewarded his supporters and employed them as a counterweight against the Confucian scholar-bureaucrats. One, Zheng He, led seven enormous voyages of exploration into the Indian Ocean as far as Arabia, the rise of new emperors and new factions diminished such extravagances, the capture of the Zhengtong Emperor during the 1449 Tumu Crisis ended them completely. The imperial navy was allowed to fall into disrepair while forced labor constructed the Liaodong palisade, haijin laws intended to protect the coasts from Japanese pirates instead turned many into smugglers and pirates themselves. The growth of Portuguese, Spanish, and Dutch trade created new demand for Chinese products and produced an influx of Japanese. This abundance of specie remonetized the Ming economy, whose money had suffered repeated hyperinflation and was no longer trusted. While traditional Confucians opposed such a prominent role for commerce and the newly rich it created, combined with crop failure, floods, and epidemic, the dynasty collapsed before the rebel leader Li Zicheng, who was defeated by the Manchu-led Eight Banner armies who founded the Qing dynasty. The Mongol-led Yuan dynasty ruled before the establishment of the Ming dynasty, consequently, agriculture and the economy were in shambles, and rebellion broke out among the hundreds of thousands of peasants called upon to work on repairing the dykes of the Yellow River. A number of Han Chinese groups revolted, including the Red Turbans in 1351, the Red Turbans were affiliated with the White Lotus, a Buddhist secret society. Zhu Yuanzhang was a peasant and Buddhist monk who joined the Red Turbans in 1352. In 1356, Zhus rebel force captured the city of Nanjing, with the Yuan dynasty crumbling, competing rebel groups began fighting for control of the country and thus the right to establish a new dynasty. In 1363, Zhu Yuanzhang eliminated his archrival and leader of the rebel Han faction, Chen Youliang, in the Battle of Lake Poyang, arguably the largest naval battle in history. Known for its ambitious use of ships, Zhus force of 200,000 Ming sailors were able to defeat a Han rebel force over triple their size, claimed to be 650. The victory destroyed the last opposing rebel faction, leaving Zhu Yuanzhang in uncontested control of the bountiful Yangtze River Valley, Zhu Yuanzhang took Hongwu, or Vastly Martial, as his era name. Hongwu made an effort to rebuild state infrastructure. He built a 48 km long wall around Nanjing, as well as new palaces, Hongwu organized a military system known as the weisuo, which was similar to the fubing system of the Tang dynasty. With a growing suspicion of his ministers and subjects, Hongwu established the Jinyiwei, some 100,000 people were executed in a series of purges during his rule
33.
Japan
–
Japan is a sovereign island nation in Eastern Asia. Located in the Pacific Ocean, it lies off the eastern coast of the Asia Mainland and stretches from the Sea of Okhotsk in the north to the East China Sea, the kanji that make up Japans name mean sun origin. 日 can be read as ni and means sun while 本 can be read as hon, or pon, Japan is often referred to by the famous epithet Land of the Rising Sun in reference to its Japanese name. Japan is an archipelago consisting of about 6,852 islands. The four largest are Honshu, Hokkaido, Kyushu and Shikoku, the country is divided into 47 prefectures in eight regions. Hokkaido being the northernmost prefecture and Okinawa being the southernmost one, the population of 127 million is the worlds tenth largest. Japanese people make up 98. 5% of Japans total population, approximately 9.1 million people live in the city of Tokyo, the capital of Japan. Archaeological research indicates that Japan was inhabited as early as the Upper Paleolithic period, the first written mention of Japan is in Chinese history texts from the 1st century AD. Influence from other regions, mainly China, followed by periods of isolation, from the 12th century until 1868, Japan was ruled by successive feudal military shoguns who ruled in the name of the Emperor. Japan entered into a period of isolation in the early 17th century. The Second Sino-Japanese War of 1937 expanded into part of World War II in 1941, which came to an end in 1945 following the bombings of Hiroshima and Nagasaki. Japan is a member of the UN, the OECD, the G7, the G8, the country has the worlds third-largest economy by nominal GDP and the worlds fourth-largest economy by purchasing power parity. It is also the worlds fourth-largest exporter and fourth-largest importer, although Japan has officially renounced its right to declare war, it maintains a modern military with the worlds eighth-largest military budget, used for self-defense and peacekeeping roles. Japan is a country with a very high standard of living. Its population enjoys the highest life expectancy and the third lowest infant mortality rate in the world, in ancient China, Japan was called Wo 倭. It was mentioned in the third century Chinese historical text Records of the Three Kingdoms in the section for the Wei kingdom, Wa became disliked because it has the connotation of the character 矮, meaning dwarf. The 倭 kanji has been replaced with the homophone Wa, meaning harmony, the Japanese word for Japan is 日本, which is pronounced Nippon or Nihon and literally means the origin of the sun. The earliest record of the name Nihon appears in the Chinese historical records of the Tang dynasty, at the start of the seventh century, a delegation from Japan introduced their country as Nihon
34.
Portugal
–
Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. It is the westernmost country of mainland Europe, to the west and south it is bordered by the Atlantic Ocean and to the east and north by Spain. The Portugal–Spain border is 1,214 kilometres long and considered the longest uninterrupted border within the European Union, the republic also includes the Atlantic archipelagos of the Azores and Madeira, both autonomous regions with their own regional governments. The territory of modern Portugal has been settled, invaded. The Pre-Celts, Celts, Carthaginians and the Romans were followed by the invasions of the Visigothic, in 711 the Iberian Peninsula was invaded by the Moors, making Portugal part of Muslim Al Andalus. Portugal was born as result of the Christian Reconquista, and in 1139, Afonso Henriques was proclaimed King of Portugal, in the 15th and 16th centuries, Portugal established the first global empire, becoming one of the worlds major economic, political and military powers. Portugal monopolized the trade during this time, and the Portuguese Empire expanded with military campaigns led in Asia. After the 1910 revolution deposed the monarchy, the democratic but unstable Portuguese First Republic was established, democracy was restored after the Portuguese Colonial War and the Carnation Revolution in 1974. Shortly after, independence was granted to almost all its overseas territories, Portugal has left a profound cultural and architectural influence across the globe and a legacy of over 250 million Portuguese speakers today. Portugal is a country with a high-income advanced economy and a high living standard. It is the 5th most peaceful country in the world, maintaining a unitary semi-presidential republican form of government and it has the 18th highest Social Progress in the world, putting it ahead of other Western European countries like France, Spain and Italy. Portugal is a pioneer when it comes to drug decriminalization, as the nation decriminalized the possession of all drugs for use in 2001. The early history of Portugal is shared with the rest of the Iberian Peninsula located in South Western Europe, the name of Portugal derives from the joined Romano-Celtic name Portus Cale. Other influences include some 5th-century vestiges of Alan settlements, which were found in Alenquer, Coimbra, the region of present-day Portugal was inhabited by Neanderthals and then by Homo sapiens, who roamed the border-less region of the northern Iberian peninsula. These were subsistence societies that, although they did not establish prosperous settlements, neolithic Portugal experimented with domestication of herding animals, the raising of some cereal crops and fluvial or marine fishing. Chief among these tribes were the Calaicians or Gallaeci of Northern Portugal, the Lusitanians of central Portugal, the Celtici of Alentejo, a few small, semi-permanent, commercial coastal settlements were also founded in the Algarve region by Phoenicians-Carthaginians. Romans first invaded the Iberian Peninsula in 219 BC, during the last days of Julius Caesar, almost the entire peninsula had been annexed to the Roman Republic. The Carthaginians, Romes adversary in the Punic Wars, were expelled from their coastal colonies and it suffered a severe setback in 150 BC, when a rebellion began in the north
35.
Europe
–
Europe is a continent that comprises the westernmost part of Eurasia. Europe is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, yet the non-oceanic borders of Europe—a concept dating back to classical antiquity—are arbitrary. Europe covers about 10,180,000 square kilometres, or 2% of the Earths surface, politically, Europe is divided into about fifty sovereign states of which the Russian Federation is the largest and most populous, spanning 39% of the continent and comprising 15% of its population. Europe had a population of about 740 million as of 2015. Further from the sea, seasonal differences are more noticeable than close to the coast, Europe, in particular ancient Greece, was the birthplace of Western civilization. The fall of the Western Roman Empire, during the period, marked the end of ancient history. Renaissance humanism, exploration, art, and science led to the modern era, from the Age of Discovery onwards, Europe played a predominant role in global affairs. Between the 16th and 20th centuries, European powers controlled at times the Americas, most of Africa, Oceania. The Industrial Revolution, which began in Great Britain at the end of the 18th century, gave rise to economic, cultural, and social change in Western Europe. During the Cold War, Europe was divided along the Iron Curtain between NATO in the west and the Warsaw Pact in the east, until the revolutions of 1989 and fall of the Berlin Wall. In 1955, the Council of Europe was formed following a speech by Sir Winston Churchill and it includes all states except for Belarus, Kazakhstan and Vatican City. Further European integration by some states led to the formation of the European Union, the EU originated in Western Europe but has been expanding eastward since the fall of the Soviet Union in 1991. The European Anthem is Ode to Joy and states celebrate peace, in classical Greek mythology, Europa is the name of either a Phoenician princess or of a queen of Crete. The name contains the elements εὐρύς, wide, broad and ὤψ eye, broad has been an epithet of Earth herself in the reconstructed Proto-Indo-European religion and the poetry devoted to it. For the second part also the divine attributes of grey-eyed Athena or ox-eyed Hera. The same naming motive according to cartographic convention appears in Greek Ανατολή, Martin Litchfield West stated that phonologically, the match between Europas name and any form of the Semitic word is very poor. Next to these there is also a Proto-Indo-European root *h1regʷos, meaning darkness. Most major world languages use words derived from Eurṓpē or Europa to refer to the continent, in some Turkic languages the originally Persian name Frangistan is used casually in referring to much of Europe, besides official names such as Avrupa or Evropa
36.
North America
–
North America is a continent entirely within the Northern Hemisphere and almost all within the Western Hemisphere. It can also be considered a subcontinent of the Americas. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the west and south by the Pacific Ocean, and to the southeast by South America and the Caribbean Sea. North America covers an area of about 24,709,000 square kilometers, about 16. 5% of the land area. North America is the third largest continent by area, following Asia and Africa, and the fourth by population after Asia, Africa, and Europe. In 2013, its population was estimated at nearly 565 million people in 23 independent states, or about 7. 5% of the worlds population, North America was reached by its first human populations during the last glacial period, via crossing the Bering land bridge. The so-called Paleo-Indian period is taken to have lasted until about 10,000 years ago, the Classic stage spans roughly the 6th to 13th centuries. The Pre-Columbian era ended with the migrations and the arrival of European settlers during the Age of Discovery. Present-day cultural and ethnic patterns reflect different kind of interactions between European colonists, indigenous peoples, African slaves and their descendants, European influences are strongest in the northern parts of the continent while indigenous and African influences are relatively stronger in the south. Because of the history of colonialism, most North Americans speak English, Spanish or French, the Americas are usually accepted as having been named after the Italian explorer Amerigo Vespucci by the German cartographers Martin Waldseemüller and Matthias Ringmann. Vespucci, who explored South America between 1497 and 1502, was the first European to suggest that the Americas were not the East Indies, but a different landmass previously unknown by Europeans. In 1507, Waldseemüller produced a map, in which he placed the word America on the continent of South America. He explained the rationale for the name in the accompanying book Cosmographiae Introductio, for Waldseemüller, no one should object to the naming of the land after its discoverer. He used the Latinized version of Vespuccis name, but in its feminine form America, following the examples of Europa, Asia and Africa. Later, other mapmakers extended the name America to the continent, In 1538. Some argue that the convention is to use the surname for naming discoveries except in the case of royalty, a minutely explored belief that has been advanced is that America was named for a Spanish sailor bearing the ancient Visigothic name of Amairick. Another is that the name is rooted in a Native American language, the term North America maintains various definitions in accordance with location and context. In Canadian English, North America may be used to refer to the United States, alternatively, usage sometimes includes Greenland and Mexico, as well as offshore islands
37.
United States
–
Forty-eight of the fifty states and the federal district are contiguous and located in North America between Canada and Mexico. The state of Alaska is in the northwest corner of North America, bordered by Canada to the east, the state of Hawaii is an archipelago in the mid-Pacific Ocean. The U. S. territories are scattered about the Pacific Ocean, the geography, climate and wildlife of the country are extremely diverse. At 3.8 million square miles and with over 324 million people, the United States is the worlds third- or fourth-largest country by area, third-largest by land area. It is one of the worlds most ethnically diverse and multicultural nations, paleo-Indians migrated from Asia to the North American mainland at least 15,000 years ago. European colonization began in the 16th century, the United States emerged from 13 British colonies along the East Coast. Numerous disputes between Great Britain and the following the Seven Years War led to the American Revolution. On July 4,1776, during the course of the American Revolutionary War, the war ended in 1783 with recognition of the independence of the United States by Great Britain, representing the first successful war of independence against a European power. The current constitution was adopted in 1788, after the Articles of Confederation, the first ten amendments, collectively named the Bill of Rights, were ratified in 1791 and designed to guarantee many fundamental civil liberties. During the second half of the 19th century, the American Civil War led to the end of slavery in the country. By the end of century, the United States extended into the Pacific Ocean. The Spanish–American War and World War I confirmed the status as a global military power. The end of the Cold War and the dissolution of the Soviet Union in 1991 left the United States as the sole superpower. The U. S. is a member of the United Nations, World Bank, International Monetary Fund, Organization of American States. The United States is a developed country, with the worlds largest economy by nominal GDP. It ranks highly in several measures of performance, including average wage, human development, per capita GDP. While the U. S. economy is considered post-industrial, characterized by the dominance of services and knowledge economy, the United States is a prominent political and cultural force internationally, and a leader in scientific research and technological innovations. In 1507, the German cartographer Martin Waldseemüller produced a map on which he named the lands of the Western Hemisphere America after the Italian explorer and cartographer Amerigo Vespucci
38.
BBC
–
The British Broadcasting Corporation is a British public service broadcaster. It is headquartered at Broadcasting House in London, the BBC is the worlds oldest national broadcasting organisation and the largest broadcaster in the world by number of employees. It employs over 20,950 staff in total,16,672 of whom are in public sector broadcasting, the total number of staff is 35,402 when part-time, flexible, and fixed contract staff are included. The BBC is established under a Royal Charter and operates under its Agreement with the Secretary of State for Culture, Media and Sport. The fee is set by the British Government, agreed by Parliament, and used to fund the BBCs radio, TV, britains first live public broadcast from the Marconi factory in Chelmsford took place in June 1920. It was sponsored by the Daily Mails Lord Northcliffe and featured the famous Australian Soprano Dame Nellie Melba, the Melba broadcast caught the peoples imagination and marked a turning point in the British publics attitude to radio. However, this public enthusiasm was not shared in official circles where such broadcasts were held to interfere with important military and civil communications. By late 1920, pressure from these quarters and uneasiness among the staff of the licensing authority, the General Post Office, was sufficient to lead to a ban on further Chelmsford broadcasts. But by 1922, the GPO had received nearly 100 broadcast licence requests, John Reith, a Scottish Calvinist, was appointed its General Manager in December 1922 a few weeks after the company made its first official broadcast. The company was to be financed by a royalty on the sale of BBC wireless receiving sets from approved manufacturers, to this day, the BBC aims to follow the Reithian directive to inform, educate and entertain. The financial arrangements soon proved inadequate, set sales were disappointing as amateurs made their own receivers and listeners bought rival unlicensed sets. By mid-1923, discussions between the GPO and the BBC had become deadlocked and the Postmaster-General commissioned a review of broadcasting by the Sykes Committee and this was to be followed by a simple 10 shillings licence fee with no royalty once the wireless manufactures protection expired. The BBCs broadcasting monopoly was made explicit for the duration of its current broadcast licence, the BBC was also banned from presenting news bulletins before 19.00, and required to source all news from external wire services. Mid-1925 found the future of broadcasting under further consideration, this time by the Crawford committee, by now the BBC under Reiths leadership had forged a consensus favouring a continuation of the unified broadcasting service, but more money was still required to finance rapid expansion. Wireless manufacturers were anxious to exit the loss making consortium with Reith keen that the BBC be seen as a service rather than a commercial enterprise. The recommendations of the Crawford Committee were published in March the following year and were still under consideration by the GPO when the 1926 general strike broke out in May. The strike temporarily interrupted newspaper production and with restrictions on news bulletins waived the BBC suddenly became the source of news for the duration of the crisis. The crisis placed the BBC in a delicate position, the Government was divided on how to handle the BBC but ended up trusting Reith, whose opposition to the strike mirrored the PMs own
39.
Netherlands
–
The Netherlands, also informally known as Holland is the main constituent country of the Kingdom of the Netherlands. It is a densely populated country located in Western Europe with three territories in the Caribbean. The European part of the Netherlands borders Germany to the east, Belgium to the south, and the North Sea to the northwest, sharing borders with Belgium, the United Kingdom. The three largest cities in the Netherlands are Amsterdam, Rotterdam and The Hague, Amsterdam is the countrys capital, while The Hague holds the Dutch seat of parliament and government. The port of Rotterdam is the worlds largest port outside East-Asia, the name Holland is used informally to refer to the whole of the country of the Netherlands. Netherlands literally means lower countries, influenced by its low land and flat geography, most of the areas below sea level are artificial. Since the late 16th century, large areas have been reclaimed from the sea and lakes, with a population density of 412 people per km2 –507 if water is excluded – the Netherlands is classified as a very densely populated country. Only Bangladesh, South Korea, and Taiwan have both a population and higher population density. Nevertheless, the Netherlands is the worlds second-largest exporter of food and agricultural products and this is partly due to the fertility of the soil and the mild climate. In 2001, it became the worlds first country to legalise same-sex marriage, the Netherlands is a founding member of the EU, Eurozone, G-10, NATO, OECD and WTO, as well as being a part of the Schengen Area and the trilateral Benelux Union. The first four are situated in The Hague, as is the EUs criminal intelligence agency Europol and this has led to the city being dubbed the worlds legal capital. The country also ranks second highest in the worlds 2016 Press Freedom Index, the Netherlands has a market-based mixed economy, ranking 17th of 177 countries according to the Index of Economic Freedom. It had the thirteenth-highest per capita income in the world in 2013 according to the International Monetary Fund, in 2013, the United Nations World Happiness Report ranked the Netherlands as the seventh-happiest country in the world, reflecting its high quality of life. The Netherlands also ranks joint second highest in the Inequality-adjusted Human Development Index, the region called Low Countries and the country of the Netherlands have the same toponymy. Place names with Neder, Nieder, Nether and Nedre and Bas or Inferior are in use in all over Europe. They are sometimes used in a relation to a higher ground that consecutively is indicated as Upper, Boven, Oben. In the case of the Low Countries / the Netherlands the geographical location of the region has been more or less downstream. The geographical location of the region, however, changed over time tremendously
40.
Folkestone
–
Folkestone /ˈfoʊkstən/ is a port town on the English Channel, in Kent, south-east England. The town lies on the edge of the North Downs at a valley between two cliffs. It was an important harbour and shipping port for most of the 19th and 20th centuries, there has been a settlement in this location since the Mesolithic era. A nunnery was founded by Eanswith, daughter of Æthelberht of Kent in the 7th century, the harbours use has diminished since the opening of the nearby Channel Tunnel and stopping of local ferry services, but still remains in active use. The area of Folkestone has been occupied since at least the Mesolithic era, in 2010, worked flints were discovered below the remains of the Folkestone Roman Villa. The East Cliff area was excavated in 1924 and most recently from 2010 -2011, on the East Cliff, an extensive Iron Age oppidum existed, which produced quern-stones on an almost industrial scale. These querns, or stones used for grinding cereals into flour, were traded for continental exports such as pottery, a modest Roman style villa was constructed over the Iron Age settlement sometime during the first century AD, followed by a more luxurious one in about 200 AD. The villa was abandoned sometime during the third or fourth century for unknown reasons, in 597 AD, monks led by St Augustine arrived at Ebbsfleet on the Isle of Thanet, on a mission from Pope Gregory to re-Christianise Britain. He was greeted by the Anglo Saxon pagan King of Kent, Ethelbert and his Christian Queen, Augustine was granted land in Canterbury where he built his church and outside the walls founded the monastery of St Peter & St Paul - now known as St Augustines. Ethelbert was succeeded as Anglo-Saxon king of Kent by his son Eadbald, in 630 AD, Eanswythe founded a nunnery on the site of her fathers castle near Folkestone by the present parish Church of St Mary & St Eanswythe. Eanswythe died c 640 AD and was made a saint. Her remains were moved into the chancel of the current church in the 12th century and they became the focus of prayer and pilgrimage such that Eanswythe was quickly adopted as the towns patron. The community grew and developed into a monastery until it was dissolved by Henry VIII and they were rediscovered in June 1885 when workmen, carrying out alterations to the high altar, found a battered lead casket immured in a niche in the north wall of the chancel. Examination by archaeologists at the time and again in 1981 confirmed that the casket was of Anglo-Saxon origin and these relics are still housed in the church close to where they were discovered in the north wall of the chancel flanked by a pair of small brass candlesticks. St Eanswythe is celebrated on 12 September each year - the date on which her relics were moved to the present chancel and she also appears on the towns seal with William Harvey, the Folkestone-born, 17th-century physician who discovered the circulation of the blood. A Norman knight held a Barony of Folkestone, which led to its entry as a part of the Cinque Ports in the thirteenth century, at the start of the Tudor period it had become a town in its own right. Wars with France meant that defences had to be built here, at the beginning of the 1800s a harbour was developed, but it was the coming of the railways in 1843 that would have the bigger impact. Until the 19th century Folkestone remained a fishing community with a seafront that was continually battered by storms
41.
Poole
–
Poole /puːl/ is a large coastal town and seaport in the county of Dorset, on the south coast of England. The town is 33 kilometres east of Dorchester, and adjoins Bournemouth to the east, the local council is Borough of Poole and was made a unitary authority in 1997, gaining administrative independence from Dorset County Council. The borough had a population of 147,645 at the 2011 census, together with Bournemouth and Christchurch, the town forms the South East Dorset conurbation with a total population of over 465,000. Human settlement in the dates back to before the Iron Age. The earliest recorded use of the name was in the 12th century when the town began to emerge as an important port. Later, the town had important trade links with North America and, at its peak during the 18th century, in the Second World War, Poole was one of the main departing points for the Normandy landings. Poole is a tourist resort, attracting visitors with its natural harbour, history. The town has a port with cross-Channel freight and passenger ferry services. The headquarters of the Royal National Lifeboat Institution are in Poole, despite their names, Poole is the home of The Arts University Bournemouth, the Bournemouth Symphony Orchestra and a significant part of Bournemouth University. The towns name derives from a corruption of the Celtic word bol, variants include Pool, Pole, Poles, Poll, Polle, Polman, and Poolman. The area around modern Poole has been inhabited for the past 2,500 years, during the 3rd century BC, Celts known as the Durotriges moved from hilltop settlements at Maiden Castle and Badbury Rings to heathland around the River Frome and Poole Harbour. The Romans landed at Poole during their conquest of Britain in the 1st century and took over an Iron Age settlement at Hamworthy, in Anglo-Saxon times, Poole was included in the Kingdom of Wessex. The settlement was used as a base for fishing and the harbour a place for ships to anchor on their way to the River Frome, following the Norman conquest of England, Poole rapidly grew into a busy port as the importance of Wareham declined. The town was part of the manor of Canford, but does not exist as an entry in the Domesday Book. The earliest written mention of Poole occurred on a document from 1196 describing the newly built St Jamess Chapel in La Pole. The Lord of the Manor, Sir William Longspée, sold a charter of liberties to the burgesses of Poole in 1248 to raise funds for his participation in the Seventh Crusade. Consequently, Poole gained a measure of freedom from feudal rule and acquired the right to appoint a mayor. In 1568, Poole gained further autonomy when it was granted independence from Dorset
42.
Vision in fishes
–
Vision is an important sensory system for most species of fish. Fish eyes are similar to the eyes of terrestrial vertebrates like birds and mammals, birds and mammals normally adjust focus by changing the shape of their lens, but fish normally adjust focus by moving the lens closer to or further from the retina. Fish retinas generally have both rod cells and cone cells, and most species have colour vision, some fish can see ultraviolet and some are sensitive to polarized light. Among jawless fish, the lamprey has well-developed eyes, while the hagfish has only primitive eyespots, Fish vision shows evolutionary adaptation to their visual environment, for example deep sea fish have eyes suited to the dark environment. Fish and other animals live in a different light environment than terrestrial species. Water absorbs light so that with increasing depth the amount of light available decreases quickly, the optical properties of water also lead to different wavelengths of light being absorbed to different degrees. For example, visible light of wavelengths is absorbed quicker than light of shorter wavelengths. Ultraviolet light is absorbed quicker yet, besides these universal qualities of water, different bodies of water may absorb light of different wavelengths due to varying salt and/or chemical presence in the water. Fish eyes are similar to those of other vertebrates – notably the tetrapods. Light enters the eye at the cornea, passing through the pupil to reach the lens, most fish species seem to have a fixed pupil size, but elasmobranches have a muscular iris which allows pupil diameter to be adjusted. Pupil shape varies, and may be e. g. circular or slit-like, lenses are normally spherical but can be slightly elliptical in some species. Compared to terrestrial vertebrates, fish lenses are more dense. In the aquatic environment there is not a difference in the refractive index of the cornea. Due to a refractive index gradient within the lens — exactly as one would expect from optical theory the spherical lenses of fish are able to form sharp images free from spherical aberration. Once light passes through the lens it is transmitted through a transparent liquid medium until it reaches the retina, like other vertebrates, the photoreceptors are on the inside layer so light must pass through layers of other neurons before it reaches them. The retina contains rod cells and cone cells, within the retina, rod cells provide high visual sensitivity, being used in low light conditions. The distribution of photoreceptors across the retina is not uniform, some areas have higher densities of cone cells, for example. Fish may have two or three areas specialized for high acuity or sensitivity, the distribution of photoreceptors may also change over time during development of the individual
43.
Cone cell
–
Cone cells, or cones, are one of three types of photoreceptor cells in the retina of mammalian eyes. They are responsible for vision and function best in relatively bright light, as opposed to rod cells. Cone cells are packed in the fovea centralis, a 0.3 mm diameter rod-free area with very thin. There are about six to seven million cones in an eye and are most concentrated towards the macula. The commonly cited figure of six million cone cells in the eye was found by Osterberg in 1935. Oysters textbook cites work by Curcio et al. indicating a close to 4.5 million cone cells and 90 million rod cells in the human retina. Cones are less sensitive to light than the rod cells in the retina and they are also able to perceive finer detail and more rapid changes in images, because their response times to stimuli are faster than those of rods. Cones are normally one of the three types, each with different pigment, namely, S-cones, M-cones and L-cones, each cone is therefore sensitive to visible wavelengths of light that correspond to short-wavelength, medium-wavelength and long-wavelength light. Being colour blind can change this, and there have been some verified reports of people with four or more types of cones, destruction of the cone cells from disease would result in blindness. Humans normally have three types of cones, the first responds the most to light of long wavelengths, peaking at about 560 nm, this type is sometimes designated L for long. The second type responds the most to light of medium-wavelength, peaking at 530 nm, the third type responds the most to short-wavelength light, peaking at 420 nm, and is designated S for short. The three types have peak wavelengths near 564–580 nm, 534–545 nm, and 420–440 nm, respectively, the difference in the signals received from the three cone types allows the brain to perceive a continuous range of colours, through the opponent process of colour vision. All of the contain the protein photopsin, with variations in its conformation causing differences in the optimum wavelengths absorbed. Similarly, blue and violet hues are perceived when the S receptor is stimulated more, cones are most sensitive to light at wavelengths around 420 nm. People with aphakia, a condition where the eye lacks a lens, at lower light levels, where only the rod cells function, the sensitivity is greatest at a blueish-green wavelength. Separate connectivity is established in the inner plexiform layer so that each connection is parallel, while it has been discovered that there exists a mixed type of bipolar cells that bind to both rod and cone cells, bipolar cells still predominantly receive their input from cone cells. Cone cells are somewhat shorter than rods, but wider and tapered, and are less numerous than rods in most parts of the retina. Structurally, cone cells have a cone-like shape at one end where a pigment filters incoming light, giving them their different response curves
44.
Ultraviolet
–
Ultraviolet is an electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays. UV radiation constitutes about 10% of the light output of the Sun. It is also produced by electric arcs and specialized lights, such as lamps, tanning lamps. Consequently, the effects of UV are greater than simple heating effects. Suntan, freckling and sunburn are familiar effects of over-exposure, along with risk of skin cancer. Living things on dry land would be damaged by ultraviolet radiation from the Sun if most of it were not filtered out by the Earths atmosphere. More-energetic, shorter-wavelength extreme UV below 121 nm ionizes air so strongly that it is absorbed before it reaches the ground, Ultraviolet is also responsible for the formation of bone-strengthening vitamin D in most land vertebrates, including humans. The UV spectrum thus has both beneficial and harmful to human health. Ultraviolet rays are invisible to most humans, the lens in a human eye ordinarily filters out UVB frequencies or higher, and humans lack color receptor adaptations for ultraviolet rays. Under some conditions, children and young adults can see ultraviolet down to wavelengths of about 310 nm, near-UV radiation is visible to some insects, mammals, and birds. Small birds have a fourth color receptor for ultraviolet rays, this gives birds true UV vision, reindeer use near-UV radiation to see polar bears, who are poorly visible in regular light because they blend in with the snow. UV also allows mammals to see urine trails, which is helpful for animals to find food in the wild. The males and females of some species look identical to the human eye. Ultraviolet means beyond violet, violet being the color of the highest frequencies of visible light, Ultraviolet has a higher frequency than violet light. He called them oxidizing rays to emphasize chemical reactivity and to them from heat rays. The terms chemical and heat rays were eventually dropped in favour of ultraviolet and infrared radiation, in 1878 the effect of short-wavelength light on sterilizing bacteria was discovered. By 1903 it was known the most effective wavelengths were around 250 nm, in 1960, the effect of ultraviolet radiation on DNA was established. The discovery of the ultraviolet radiation below 200 nm, named vacuum ultraviolet because it is absorbed by air, was made in 1893 by the German physicist Victor Schumann
45.
Primary color
–
A set of primary colors is a small, arbitrary set of pigmented physical media, lights or purely abstract elements of a mathematical colorspace model. Distinct colors from a larger gamut can be specified in terms of a mixture of colors which facilitates technological applications such as painting, electronic displays. Any small set of pigments or lights are imperfect physical primary colors in that they cannot be mixed to yield all possible colors that can be perceived by the color vision system. In an additive set of colors, as in coincident projected lights or in electronic visual displays, in a subtractive set of colors, as in mixing of pigments or dyes for printing, the colors magenta, yellow and cyan are normally used. See RGB color model, and CMYK color model for more on these sets of primary colors. Primary colors are not a property of light but are related to the color vision system in animals. The human eye normally contains three types of color photoreceptors that are associated with specialized cone cells. Each photoreceptor responds to different ranges of the electromagnetic spectrum. Humans and other species with three types of color photoreceptor are known as trichromats. Color appearance models like CIECAM02 describe color more generally in six dimensions, most placental mammals other than primates have only two types of color photoreceptor and are therefore dichromats while birds and marsupials are tetrachromats with four color photoreceptor types. There is no peer reviewed scholarly work that has confirmed the existence of a functional human tetrachromat though they are suspected to exist. Demonstrating improved spectral discrimination in any animal can be difficult since complex sets of neurons affect color perception in ways that are difficult to interrogate. Before the nature of colorimetry and visual physiology were well understood a number of color models assigned primary colors to different hues. Young originally proposed red, green and violet, and Maxwell changed violet to blue, Helmholtz proposed a slightly red, a vegetation-green, slightly yellowish. In modern understanding, human cells do not correspond precisely to a specific set of primary colors. There are hundreds of available pigments for visual artists to use. A common approach is to use just a palette of pigments that can be physically mixed to any color that the artist desires in the final work. Contemporary classical realists have often advocated that a palette of white, red, yellow
46.
Tetrachromacy
–
Tetrachromacy is the condition of possessing four independent channels for conveying color information, or possessing four types of cone cells in the eye. Organisms with tetrachromacy are called tetrachromats, tetrachromacy is demonstrated among several species of birds, fish, amphibians, reptiles, insects and some mammals. It was the condition of most mammals in the past. The normal explanation of tetrachromacy is that the retina contains four types of higher-intensity light receptors with different absorption spectra. This means that the animal may see wavelengths beyond those of a human beings eyesight. Species with tetrachromatic color vision may have a physiological advantage over rival species. The goldfish and zebrafish are examples of tetrachromats, containing cone cells sensitive for red, green, blue and ultraviolet light. Some species of birds, such as the finch and the Columbidae, use the ultraviolet wavelength 300–400 nm specific to tetrachromatic color vision as a tool during mate selection. When selecting for mates, ultraviolet plumage and skin coloration show a level of selection. A typical bird eye will respond to wavelengths from about 300 to 700 nm, in terms of frequency, this corresponds to a band in the vicinity of 430–1000 THz. Most birds have retinas with four types of cone cells that are believed to mediate tetrachromatic color vision. Bird color vision is further improved by the filtering of pigmented oil droplets that are located in the photoreceptors, the oil droplets filter incident light before it reaches the visual pigment in outer segments of the photoreceptors. The four cone types, and the specialization of pigmented oil droplets, however, more recent research has suggested that tetrachromacy in birds only provide birds with a larger visual spectrum than that in humans, while the spectral resolution is similar. Foraging insects can see wavelengths that flowers reflect, pollination being a mutualistic relationship, foraging insects and plants have coevolved, both increasing wavelength range, in perception, in reflection and variation. Directional selection has led plants to display increasingly diverse amounts of color variations extending into the color scale. Some unidentified pollinators may use tetrachromatic color vision to increase and maintain a higher foraging success rate over their trichromatic competitors, in areas where reindeer live, the sun remains very low in the sky for long periods. This means the light is scattered such that the majority of light that reaches objects is blue or UV, some parts of the environment absorb UV light and therefore to UV-sensitive reindeer, appear to be black, strongly contrasting with the snow. These include urine, lichens and fur, although reindeer do not possess a specific UV opsin, retinal responses to 330 nm have been recorded, mediated by other opsins
.jpg)
.jpg)
.JPG)
. PMID 16812735.
