1.
Lancelot
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Sir Lancelot du Lac was one of the Knights of the Round Table in the Arthurian legend. Traditional scholars thought that they are the same due to the fact that their names are similar. One suggestion has been that the name may have been an invention by Chretien de Troyes, given the evidence of LAncelot. Another suggestion is that the name may have derived from Geoffrey of Monmouths Anguselaus. However, one scholar has suggested that Lancelot may be a variant of the name Lancelin, Lancelot or Lancelin may have instead been the hero of an independent folk-tale which had contact with and was ultimately absorbed into the Arthurian tradition. F. Campbell in his Tales of the West Highlands, the character Lancelot is first introduced by writer Chrétien de Troyes in the 12th century. In Chrétiens earliest known work Erec and Enide, the name Lancelot appears as third on a list of knights at King Arthurs court. The fact that Lancelots name follows Gawain and Erec indicates the importance of the knight at court. Here, Lancelot takes an important role as one of the knights that Cligès must overcome in his quest. It is not until Chrétiens Le Chevalier de la Charrette, however, in this text, he is presented as the most formidable knight at King Arthurs court. His adulterous relationship with the Queen is also introduced in this text, according to Pamela Raabe, Lancelot is portrayed in Chrétien de Troyes’ work as the bravest of knights and one whom everyone is forced to describe as uniquely perfect. His deeds are recounted for their uniqueness, not only among living knights, the problem is that critics have been unable to agree on how to reconcile his perfect “saintliness” with his obvious adultery with King Arthur’s Guinevere. How can the lovers’ consummation be considered a “saintly affair” when it is also adultery, and that adultery is against King Arthur, to whom all knights owe selfless respect, according to Arthurian politics and William Bowman Piper. It is also Chrétien who first gives Lancelot the name Lancelot du Lac which was picked up by the Anglo-French Lancelot-Grail. Lancelot is constantly tied to the Christianity associated with Arthurian Legend, Raabe compares Lancelot’s quest for Guinevere in “Lancelot, the Knight of the Cart” to Everyman’s quest for salvation and Christ’s quest for the human soul. This becomes intensified when he becomes the saviour of the captives of Logres. Danielle MacBain’s study of Thomas Malory’s Le Morte dArthur claims that Lancelot’s affair with Guinevere is often seen as parallel to that of Tristram and Iseult. MacBain suggests that it is Lancelot who is identified with the tragedy of chance
2.
Branchiostoma lanceolatum
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Branchiostoma lanceolatum is a lancelet in the subphylum Cephalochordata. It is a marine invertebrate found in soft substrates in shallow seas and it is used as a model organism to study the development of vertebrates. The mitochondrial genome has been sequenced, Branchiostoma lanceolatum has an elongated body, flattened laterally and pointed at both ends. A stiffening rod of tightly packed cells, the notochord, extends the length of the body. Above it is a cord with a single frontal eye. The mouth is on the underside of the body and is surrounded by a tuft of 20 or 30 cirri or slender sensory appendages, the gut runs just below the notochord from the mouth to the anus, in front of the tail. There is a flap-like, vertical fin surrounding the pointed tail, gas exchange takes place as water passes through gill slits in the mid region, and segmented gonads lie just behind these. The animal is white and semi-transparent which enables the internal organs to be seen from outside. Its appearance is similar to a primitive fish and it can grow up to 6 cm long. Branchiostoma lanceolatum is found in seas in the north-east Atlantic Ocean, from Norway, Scotland as well as further south to the Mediterranean Sea. Its range has expanded through the Suez Canal to the parts of the Indian Ocean. It burrows in soft substrates such as sand, gravel and shell fragments and is quite particular as to the size of the particles and it occurs from the low tide mark down to about 40 metres. In the North Sea, breeding takes place in June and July, the mature adult Branchiostoma lanceolatum, aged 2 to 3 years, congregate in masses on the sea floor. Individuals are either male or female and spawn once a year, the eggs are laid and fertilisation takes place externally. The early larval stages take place in the substrate but a little later and they are elongated and flattened laterally and have a swollen region around the gill slits. These slits number 6 to 19, the number increasing as the passes through its various stages. The larvae have a daily migration. Each evening they rise to near the surface of the sea and in the morning they sink through the column, feeding on phytoplankton, copepods
3.
Taxonomy (biology)
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Taxonomy is the science of defining groups of biological organisms on the basis of shared characteristics and giving names to those groups. The exact definition of taxonomy varies from source to source, but the core of the remains, the conception, naming. There is some disagreement as to whether biological nomenclature is considered a part of taxonomy, the broadest meaning of taxonomy is used here. The word taxonomy was introduced in 1813 by Candolle, in his Théorie élémentaire de la botanique, the term alpha taxonomy is primarily used today to refer to the discipline of finding, describing, and naming taxa, particularly species. In earlier literature, the term had a different meaning, referring to morphological taxonomy, ideals can, it may be said, never be completely realized. They have, however, a value of acting as permanent stimulants. Some of us please ourselves by thinking we are now groping in a beta taxonomy, turrill thus explicitly excludes from alpha taxonomy various areas of study that he includes within taxonomy as a whole, such as ecology, physiology, genetics, and cytology. He further excludes phylogenetic reconstruction from alpha taxonomy, thus, Ernst Mayr in 1968 defined beta taxonomy as the classification of ranks higher than species. This activity is what the term denotes, it is also referred to as beta taxonomy. How species should be defined in a group of organisms gives rise to practical and theoretical problems that are referred to as the species problem. The scientific work of deciding how to define species has been called microtaxonomy, by extension, macrotaxonomy is the study of groups at higher taxonomic ranks, from subgenus and above only, than species. While some descriptions of taxonomic history attempt to date taxonomy to ancient civilizations, earlier works were primarily descriptive, and focused on plants that were useful in agriculture or medicine. There are a number of stages in scientific thinking. Early taxonomy was based on criteria, the so-called artificial systems. Later came systems based on a complete consideration of the characteristics of taxa, referred to as natural systems, such as those of de Jussieu, de Candolle and Bentham. The publication of Charles Darwins Origin of Species led to new ways of thinking about classification based on evolutionary relationships and this was the concept of phyletic systems, from 1883 onwards. This approach was typified by those of Eichler and Engler, the advent of molecular genetics and statistical methodology allowed the creation of the modern era of phylogenetic systems based on cladistics, rather than morphology alone. Taxonomy has been called the worlds oldest profession, and naming and classifying our surroundings has likely been taking place as long as mankind has been able to communicate
4.
Animal
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Animals are multicellular, eukaryotic organisms of the kingdom Animalia. The animal kingdom emerged as a clade within Apoikozoa as the group to the choanoflagellates. Animals are motile, meaning they can move spontaneously and independently at some point in their lives and their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later in their lives. All animals are heterotrophs, they must ingest other organisms or their products for sustenance, most known animal phyla appeared in the fossil record as marine species during the Cambrian explosion, about 542 million years ago. Animals can be divided broadly into vertebrates and invertebrates, vertebrates have a backbone or spine, and amount to less than five percent of all described animal species. They include fish, amphibians, reptiles, birds and mammals, the remaining animals are the invertebrates, which lack a backbone. These include molluscs, arthropods, annelids, nematodes, flatworms, cnidarians, ctenophores, the study of animals is called zoology. The word animal comes from the Latin animalis, meaning having breath, the biological definition of the word refers to all members of the kingdom Animalia, encompassing creatures as diverse as sponges, jellyfish, insects, and humans. Aristotle divided the world between animals and plants, and this was followed by Carl Linnaeus, in the first hierarchical classification. In Linnaeuss original scheme, the animals were one of three kingdoms, divided into the classes of Vermes, Insecta, Pisces, Amphibia, Aves, and Mammalia. Since then the last four have all been subsumed into a single phylum, in 1874, Ernst Haeckel divided the animal kingdom into two subkingdoms, Metazoa and Protozoa. The protozoa were later moved to the kingdom Protista, leaving only the metazoa, thus Metazoa is now considered a synonym of Animalia. Animals have several characteristics that set apart from other living things. Animals are eukaryotic and multicellular, which separates them from bacteria and they are heterotrophic, generally digesting food in an internal chamber, which separates them from plants and algae. They are also distinguished from plants, algae, and fungi by lacking cell walls. All animals are motile, if only at life stages. In most animals, embryos pass through a stage, which is a characteristic exclusive to animals. With a few exceptions, most notably the sponges and Placozoa and these include muscles, which are able to contract and control locomotion, and nerve tissues, which send and process signals
5.
Chordate
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Chordates are deuterostomes, as during the embryo development stage the anus forms before the mouth. They are also bilaterally symmetric coelomates, in the case of vertebrate chordates, the notochord is usually replaced by a vertebral column during development, and they may have body plans organized via segmentation. There are also additional extinct taxa, the Vertebrata are sometimes considered as a subgroup of the clade Craniata, consisting of chordates with a skull, the Craniata and Tunicata compose the clade Olfactores. Of the more than 65,000 living species of chordates, the worlds largest and fastest animals, the blue whale and peregrine falcon respectively, are chordates, as are humans. Fossil chordates are known from at least as early as the Cambrian explosion, Hemichordata, which includes the acorn worms, has been presented as a fourth chordate subphylum, but it now is usually treated as a separate phylum. The Hemichordata, along with the Echinodermata, form the Ambulacraria, the Chordata and Ambulacraria form the superphylum Deuterostomia, composed of the deuterostomes. Attempts to work out the relationships of the chordates have produced several hypotheses. All of the earliest chordate fossils have found in the Early Cambrian Chengjiang fauna. Because the fossil record of early chordates is poor, only molecular phylogenetics offers a prospect of dating their emergence. However, the use of molecular phylogenetics for dating evolutionary transitions is controversial and it has also proved difficult to produce a detailed classification within the living chordates. Attempts to produce family trees shows that many of the traditional classes are paraphyletic. While this has been known since the 19th century, an insistence on only monophyletic taxa has resulted in vertebrate classification being in a state of flux. Although the name Chordata is attributed to William Bateson, it was already in prevalent use by 1880, ernst Haeckel described a taxon comprising tunicates, cephalochordates, and vertebrates in 1866. Though he used the German vernacular form, it is allowed under the ICZN code because of its subsequent latinization, among the vertebrate sub-group of chordates the notochord develops into the spine, and in wholly aquatic species this helps the animal to swim by flexing its tail. In fish and other vertebrates, this develops into the spinal cord, the pharynx is the part of the throat immediately behind the mouth. In fish, the slits are modified to form gills, a muscular tail that extends backwards behind the anus. This is a groove in the wall of the pharynx. In filter-feeding species it produces mucus to gather food particles, which helps in transporting food to the esophagus and it also stores iodine, and may be a precursor of the vertebrate thyroid gland
6.
Cephalochordate
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A cephalochordate is an animal in the chordate subphylum, Cephalochordata. They are characterized as chordates, as they possess all 5 of the chordate characteristics during larval stages and this includes, notocord, dorsal nerve cord, endostyle, pharynx and post-anal tail. Cephalochordates are represented in the oceans by the Amphioxiformes. Along with its sister phylum, Urochordata, Cephalochordata can be classified as belonging to the taxon Protochordata, the members of this subphylum are very small and have no hard parts, making their fossils difficult to find. Fossilized species have found in very old rocks predating vertebrates. There is a famous fossil shale from the Middle Cambrian, the Burgess Shale of British Columbia, recently, a different cephalochordate fossil has been found in south China. It dates to the early Cambrian period, and is the earliest known fossil of the cephalochordate lineage, members of this lineage have numerous gill slits, and have separate sexes. Phylogeny is based on a combination of studies of extinct and extant species, cephalochordates employ a filter feeding system to consume microorganisms. The oral hood serves as the entrance for food particles, and possesses buccal cirri, epithelial cilia lining the mouth and pharynx form a specialized wheel organ situated at the dorsal and posterior end of the cavity. The motion of the cilia resembles the motion of a wheel, hence the organs name. Behind this organ is the velum, which acts as a filter before food enters the pharynx. The food particles adhere to secreted mucus on the bars before being brought to the epibranchial groove on the dorsal side of the pharynx. Following this, the food is transferred to the gut, and this excess water passes through the atriopore and is then excreted from the body
7.
Asymmetronidae
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They are the modern representatives of the subphylum Cephalochordata, formerly thought to be the sister group of the craniates. In Asia, they are harvested commercially as food for humans and they are an important object of study in zoology as they provide indications about the evolutionary origins of the vertebrates. Lancelets serve as an intriguing comparison point for tracing how vertebrates have evolved and adapted, although lancelets split from vertebrates more than 520 million years ago, their genomes hold clues about evolution, particularly how vertebrates have employed old genes for new functions. They are regarded as similar to the archetypal vertebrate form, the first representative organism of the group to be described was Branchiostoma lanceolatum. It was described by Peter Simon Pallas in 1774 as molluscan slugs in the genus Limax and it was not until 1834 that Gabriel Costa brought the phylogenetic position of the group closer to the agnathan vertebrates, including it in the new genus Branchiostoma. In 1836, Yarrel renamed the genus as Amphioxus, now considered a synonym of the genus Branchiostoma. Today, the term amphioxus is still used as a name for the Amphioxiformes, along with lancelet. A non-technical review of all aspects of biology is, Stokes, M. D. and Holland. The genome of the Florida lancelet has been sequenced, lancelets are typically 5 centimetres long, or 7 centimetres at the longest. They have a translucent, somewhat fish-like body, but without any paired fins or other limbs, a relatively poorly developed tail fin is present, so they are not especially good swimmers. While they do possess some cartilage-like material stiffening the gill slits, mouth, in common with vertebrates, lancelets have a hollow nerve cord running along the back, pharyngeal slits and a tail that runs past the anus. Also like vertebrates, the muscles are arranged in blocks called myomeres, unlike vertebrates, the dorsal nerve cord is not protected by bone but by a simpler notochord made up of a cylinder of cells that are closely packed to form a toughened rod. The lancelet notochord, unlike the vertebrate spine, extends into the head and this gives the subphylum its name. The nerve cord is only larger in the head region than in the rest of the body. However, developmental gene expression and Transmission electron microscopy indicate the presence of a diencephalic forebrain, a possible midbrain, lancelets have two known kinds of light-sensing structures, Joseph cells, and Hesse organs, as well as a frontal eye and lamellar body. The frontal eye is thought to be light-sensitive, although this has not been confirmed by electrophysiological measurement. The lamellar body, a homologue of the pineal body, was once thought to be light-sensitive. All of these organs and structures are located in the tube, with the frontal eye at the front, followed by the lamellar body, the Joseph cells
8.
Synonym (taxonomy)
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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
9.
Temperate climate
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In geography, temperate or tepid latitudes of Earth lie between the tropics and the polar regions. The temperatures in these regions are relatively moderate, rather than extremely hot or cold. The north temperate zone extends from the Tropic of Cancer to the Arctic Circle, the south temperate zone extends from the Tropic of Capricorn to the Antarctic Circle. In some climate classifications, the zone is often divided into several smaller climate zones. These include Humid subtropical climate, Mediterranean climate, oceanic, subtropical climates are located between 23. 5° and 35. 0° north or south latitude on the eastern or leeward sides of landmasses. This climate has long, generally hot, summers and short, mild winters and these climates may occur in southern Asia, the southeastern United States, parts of eastern Australia, and in eastern coastal South America. Mediterranean climates, occur between 30° and 42° north and south latitude, on the sides of landmasses. This climate has hot summers and short mild winters, however, seasonal rainfall is the opposite of that of the subtropical humid type. These climates occur near the rimlands of the Mediterranean Sea, in western Australia, in California, the oceanic climates occur in the higher middle latitudes, between 45° and 60° north and south latitude. They are created by the flow from the cool high latitude oceans to their west. This causes the climate to have cool summers and cool winters, annual rainfall is spread throughout the entire year. Regions with this climate include Western Europe, northwestern North America, the Continental climates occur in middle latitudes, between 35° or 40° to 55°. These climates are normally inland or on sides of landmasses. They feature warm to hot summers and cold winters, with a large temperature variation. Regions with this climate include northern temperate Asia, the northern United States, southern Canada, the vast majority of the worlds human population resides in temperate zones, especially in the northern hemisphere, due to its greater mass of land. The richest temperate flora in the world is found in southern Africa, geographical zone Habitat Köppen climate classification Middle latitudes Polar circle Subtropics
10.
Norway
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The Antarctic Peter I Island and the sub-Antarctic Bouvet Island are dependent territories and thus not considered part of the Kingdom. Norway also lays claim to a section of Antarctica known as Queen Maud Land, until 1814, the kingdom included the Faroe Islands, Greenland, and Iceland. It also included Isle of Man until 1266, Shetland and Orkney until 1468, Norway has a total area of 385,252 square kilometres and a population of 5,258,317. The country shares a long border with Sweden. Norway is bordered by Finland and Russia to the north-east, Norway has an extensive coastline, facing the North Atlantic Ocean and the Barents Sea. King Harald V of the Dano-German House of Glücksburg is the current King of Norway, erna Solberg became Prime Minister in 2013, replacing Jens Stoltenberg. A constitutional monarchy, Norway divides state power between the Parliament, the Cabinet and the Supreme Court, as determined by the 1814 Constitution, the kingdom is established as a merger of several petty kingdoms. By the traditional count from the year 872, the kingdom has existed continuously for 1,144 years, Norway has both administrative and political subdivisions on two levels, counties and municipalities. The Sámi people have an amount of self-determination and influence over traditional territories through the Sámi Parliament. Norway maintains close ties with the European Union and the United States, the country maintains a combination of market economy and a Nordic welfare model with universal health care and a comprehensive social security system. Norway has extensive reserves of petroleum, natural gas, minerals, lumber, seafood, the petroleum industry accounts for around a quarter of the countrys gross domestic product. On a per-capita basis, Norway is the worlds largest producer of oil, the country has the fourth-highest per capita income in the world on the World Bank and IMF lists. On the CIAs GDP per capita list which includes territories and some regions, from 2001 to 2006, and then again from 2009 to 2017, Norway had the highest Human Development Index ranking in the world. It also has the highest inequality-adjusted ranking, Norway ranks first on the World Happiness Report, the OECD Better Life Index, the Index of Public Integrity and the Democracy Index. Norway has two names, Noreg in Nynorsk and Norge in Bokmål. The name Norway comes from the Old English word Norðrveg mentioned in 880, meaning way or way leading to the north. In contrasting with suðrvegar southern way for Germany, and austrvegr eastern way for the Baltic, the Anglo-Saxon of Britain also referred to the kingdom of Norway in 880 as Norðmanna land. This was the area of Harald Fairhair, the first king of Norway, and because of him
11.
Subtropics
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The subtropics are geographic and climate zones located roughly between the tropic circle of latitude at 23.5 latitude and temperate latitudes. Subtropical climates are characterized by warm to hot summers and cool to mild winters with infrequent frost. Subtropical climates can occur at elevations within the tropics, such as in the southern end of the Mexican Plateau and in Vietnam. Six climate classifications use the term to define the various temperature. A great portion of the deserts are located within the subtropics. Within savanna regimes in the subtropics, a wet season is seen annually during the summer, within Mediterranean climate regimes, the wet season occurs during the winter. Areas bordering warm oceans are prone to heavy rainfall from tropical cyclones. Plants such as palms, citrus, mango, lychee, the tropics have been historically defined as lying between the Tropic of Cancer and Tropic of Capricorn, located at 23. 45° north and south latitude respectively. The poleward fringe of the subtropics is located at approximately 40° north and south latitude respectively, northern fringes of the type can go further north due to moderating effects of ocean streams, like in parts of Southern Europe due to heat transported by the Gulf Stream. Several methods have used to define the subtropical climate. In the Trewartha climate classification, a subtropical region should have at least eight months with a temperature greater than 10 °C. According to the Troll-Paffen climate classification, there exists one large subtropical zone named the warm-temperate subtropical zone. According to the E. Neef climate classification, the zone is divided into two parts, Rainy winters of the west sides and Eastern subtropical climate. According to the Wilhelm Lauer & Peter Frankenberg climate classification, the zone is divided into three parts, high-continental, continental, and maritime. According to the Siegmund/Frankenberg climate classification, subtropical is one of six zones in the world. Heating of the earth near the equator leads to large amounts of upward motion and convection along the trough or Intertropical convergence zone. The upper-level divergence over the near-equatorial trough leads to air rising and moving away from the equator aloft, as the air moves towards the Mid-Latitudes, it cools and sinks, which leads to subsidence near the 30th parallel of both hemispheres. This circulation is known as the Hadley cell and leads to the formation of the subtropical ridge, many of the worlds deserts are caused by these climatological high-pressure areas, located within the subtropics
12.
Whale fall
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A whale fall is the carcass of a cetacean that has fallen into the bathyal or abyssal zone on the ocean floor. They can create complex localized ecosystems that supply sustenance to deep-sea organisms for decades and this is unlike in shallower waters, where a whale carcass will be consumed by scavengers over a relatively short period of time. It was with the development of robotic exploration that whale falls were first observed in the late 1970s. Organisms that have been observed at deep-sea whale falls include giant isopods, squat lobsters, bristleworms, prawns, shrimp, lobsters, hagfish, Osedax, crabs, sea cucumbers, and sleeper sharks. Whale falls are able to occur in the open ocean due to cold temperatures. In the coastal ocean, an incidence of predators as well as warmer waters hasten the decomposition of whale carcasses. Carcasses may also float due to gases, keeping the carcass at the surface. In the deep-sea, cold temperatures slow decomposition rates, and high hydrostatic pressures increase gas solubility, allowing food falls to remain intact, there have also been studies based on the carcasses of other, non-mammalian marine vertebrates that have fallen to the deep sea. Whale sharks inhabit waters of roughly 1,000 meters depth regularly, many eelpouts were found surrounding the whale shark with some evidence of direct feeding as boreholes were observed on the carcass. Another theory suggests that the eelpouts were waiting for their prey, amphipods. The three rays found were at varying stages of decomposition, leading to varying assemblages found surrounding the individuals, a higher abundance of scavengers was found surrounding the more intact individuals, including scavengers typical of whale falls like hagfish. Around the least intact individual a bacterial mat was observed in the zone of enrichment, overall, the four carcasses observed showed no evidence of progression past the scavenger stage. Osedax worms have the ability to extract collagen from bones as well as lipids, although no Osedax were found on the non-mammalian remains in this study, their absence may have been due to the timing of observation, and the Osedax had not yet colonized the carcasses. The amount of carbon tied up in a single whale carcass is roughly equivalent to the amount of carbon exported to a hectare of abyssal ocean floor in 100–200 years. Whales and some large marine animals feed on and follow large aggregations of zooplankton for sustenance. Biological pump models indicate that an amount of carbon uptake by the deep sea is not supplied by particulate organic carbon alone. Lateral advection of carbon, especially in coastal areas contributes to this deficit in the model, various percentages of the food fall contribution to the total carbon flux to the deep ocean have been hypothesized, ranging from 0. 3% to 4%. There is growing evidence that the contribution of food falls to the ocean carbon flux is larger than originally proposed
13.
Craniate
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A craniate is a member of the Craniata, a proposed clade of chordate animals with a skull of hard bone or cartilage. Included in the clade are the vertebrates, and non-vertebrate chordates with skulls, living representatives are the Myxini, Hyperoartia, and the much more numerous Gnathostomata. The craniate head consists of a brain, sense organs, including eyes, in addition to distinct crania, craniates possess many derived characteristics, which have allowed for more complexity to follow. In general, craniates are much more active than tunicates and lancelets and, as a result, have greater metabolic demands, aquatic craniates have gill slits, which are connected to muscles and nerves that pump water through the slits, engaging in both feeding and gas exchange. Muscles line the canal, moving food through the canal. Craniates have cardiovascular systems that include a heart with two or more chambers, red cells, and oxygen transporting hemoglobin, as well as kidneys. Linnaeus used the terms Craniata and Vertebrata interchangeably to include lampreys, jawed fishes, hagfishes were classified as Vermes, possibly representing a transitional form between worms and fishes. Dumeril grouped hagfishes and lampreys in the taxon Cyclostomi, characterized by horny teeth borne on an apparatus, a large notochord as adults. Cyclostomes were regarded as either degenerate cartilaginous fishes or primitive vertebrates, cope coined the name Agnatha for a group that included the cyclostomes and a number of fossil groups in which jaws could not be observed. Vertebrates were subsequently divided into two major sister-groups, the Agnatha and the Gnathostomata, stensiö suggested that the two groups of living agnathans arose independently from different groups of fossil agnathans. e. On this basis Janvier proposed to use the names Vertebrata and Craniata as two distinct and nested taxa, the argument is that, if Cyclostomata is indeed monophyletic, Vertebrata would return to its old content and the name Craniata, being superfluous, would become a junior synonym. Lines show probable evolutionary relationships, including extinct taxa, which are denoted with a dagger, the positions of the Lancelet, Tunicate, and Craniata clades are as reported in the scientific journal Nature. Note that this cladogram, in showing the extant cyclostomes as paraphyletic, is contradicted by all recent molecular data. Extinct genera Haikouella and Haikouichthys Campbell, Neil A. Reece, cleveland P. Hickman, J. Roberts, L. S. Keen, S. L. Larson, A. & Eisenhour, D. J. Animal Diversity, Fourth Edition. CS1 maint, Uses authors parameter Cracraft, Joel, Donoghue, new York, Oxford University Press US. Delarbre, Christiane, Gallut, C, Barriel, V, Janvier, P, Gachelin, G, complete Mitochondrial DNA of the Hagfish, Eptatretus burgeri, The Comparative Analysis of Mitochondrial DNA Sequences Strongly Supports the Cyclostome Monophyly. Parker, T. J. Haswell, W. A
14.
Domesticated animal
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This includes species which are semi-domesticated, undomesticated but captive-bred on a commercial scale, or commonly wild-caught, at least occasionally captive-bred, and tameable. A number of factors determine how quickly any changes may occur in a species, however, domestication is a gradual process, i. e. there is no precise moment in the history of a given species when it can be considered to have become fully domesticated. Archaeozoology has identified three classes of animal domesticates, commensals, adapted to a niche, prey animals sought for food. To sort the tables chronologically by date of domestication, refresh your browser window, as clicking the Date column heading will mix AD, due to the somewhat unclear outlines of what, precisely, constitutes domestication, there are some species that may or may not be fully domesticated. There are also species that are used or kept as pets by humans. Most animals on this table are at least somewhat altered from wild animals by their extensive interactions with humans. Many could not be released into the wild, or are in some way dependent on humans
15.
Zoology
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The term is derived from Ancient Greek ζῷον, zōion, i. e. animal and λόγος, logos, i. e. knowledge, study. The history of zoology traces the study of the kingdom from ancient to modern times. This ancient work was developed in the Middle Ages by Muslim physicians. During the Renaissance and early period, zoological thought was revolutionized in Europe by a renewed interest in empiricism. Microscopy revealed the unknown world of microorganisms, laying the groundwork for cell theory. The growing importance of natural theology, partly a response to the rise of mechanical philosophy, over the 18th and 19th centuries, zoology became an increasingly professional scientific discipline. Naturalists began to reject essentialism and consider the importance of extinction, cell theory provided a new perspective on the fundamental basis of life. These developments, as well as the results from embryology and paleontology, were synthesized in Charles Darwins theory of evolution by natural selection. In 1859, Darwin placed the theory of evolution on a new footing, by his discovery of a process by which organic evolution can occur. Darwin gave new direction to morphology and physiology, by uniting them in a biological theory. The end of the 19th century saw the fall of spontaneous generation, cell biology studies the structural and physiological properties of cells, including their behavior, interactions, and environment. This is done on both the microscopic and molecular levels, for single-celled organisms such as bacteria as well as the cells in multicellular organisms such as humans. Understanding the structure and function of cells is fundamental to all of the biological sciences, the similarities and differences between cell types are particularly relevant to molecular biology. Anatomy considers the forms of macroscopic structures such as organs and organ systems and it focuses on how organs and organ systems work together in the bodies of humans and animals, in addition to how they work independently. Anatomy and cell biology are two studies that are related, and can be categorized under structural studies. Physiology studies the mechanical, physical, and biochemical processes of living organisms by attempting to understand how all of the function as a whole. The theme of structure to function is central to biology, for example, what is learned about the physiology of yeast cells can also apply to human cells. The field of animal physiology extends the tools and methods of physiology to non-human species
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Vertebrate
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Vertebrates /ˈvɜːrtᵻbrᵻts/ comprise all species of animals within the subphylum Vertebrata /-ɑː/. Vertebrates represent the majority of the phylum Chordata, with currently about 66,000 species described. Vertebrates include the fish and the jawed vertebrates, which include the cartilaginous fish. A bony fish known as the lobe-finned fishes is included with tetrapods, which are further divided into amphibians, reptiles, mammals. Extant vertebrates range in size from the frog species Paedophryne amauensis, at as little as 7.7 mm, to the blue whale, vertebrates make up less than five percent of all described animal species, the rest are invertebrates, which lack vertebral columns. The vertebrates traditionally include the hagfish, which do not have proper vertebrae due to their loss in evolution, though their closest living relatives, hagfish do, however, possess a cranium. For this reason, the vertebrate subphylum is sometimes referred to as Craniata when discussing morphology, molecular analysis since 1992 has suggested that hagfish are most closely related to lampreys, and so also are vertebrates in a monophyletic sense. Others consider them a group of vertebrates in the common taxon of craniata. The word origin of vertebrate derives from the Latin word vertebratus, the Proto-Indo-European language origins are still unclear. Vertebrate is derived from the vertebra, which refers to any of the bones or segments of the spinal column. All vertebrates are built along the basic body plan, a stiff rod running through the length of the animal, with a hollow tube of nervous tissue above it. In all vertebrates, the mouth is found at, or right below, the remaining part of the body continuing after the anus forms a tail with vertebrae and spinal cord, but no gut. However, a few vertebrates have secondarily lost this anatomy, retaining the notochord into adulthood, such as the sturgeon, jawed vertebrates are typified by paired appendages, but this trait is not required in order for an animal to be a vertebrate. All basal vertebrates breathe with gills, the gills are carried right behind the head, bordering the posterior margins of a series of openings from the pharynx to the exterior. Each gill is supported by a cartilagenous or bony gill arch, the bony fish have three pairs of arches, cartilaginous fish have five to seven pairs, while the primitive jawless fish have seven. The vertebrate ancestor no doubt had more arches than this, as some of their relatives have more than 50 pairs of gills. In amphibians and some primitive fishes, the larvae bear external gills. These are reduced in adulthood, their function taken over by the gills proper in fishes, some amphibians retain the external larval gills in adulthood, the complex internal gill system as seen in fish apparently being irrevocably lost very early in the evolution of tetrapods
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Genome
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In modern molecular biology and genetics, a genome is the genetic material of an organism. The genome includes both the genes, the noncoding DNA and the material of the mitochondria and chloroplasts. The term genome was created in 1920 by Hans Winkler, professor of botany at the University of Hamburg, the Oxford Dictionary suggests the name is a blend of the words gene and chromosome. However, see omics for a thorough discussion. A few related -ome words already existed—such as biome, rhizome, Some organisms have multiple copies of chromosomes, diploid, triploid, tetraploid and so on. In classical genetics, in a sexually reproducing organism the gamete has half the number of chromosomes of the somatic cell, the halving of the genetic material in gametes is accomplished by the segregation of homologous chromosomes during meiosis. Additionally, the genome can comprise non-chromosomal genetic elements such as viruses, plasmids, even in species that exist in only one sex, what is described as a genome sequence may be a composite read from the chromosomes of various individuals. Colloquially, the genetic makeup is sometimes used to signify the genome of a particular individual or organism. Both the number of pairs and the number of genes vary widely from one species to another. The only exception in humans is found in red blood cells which become enucleated during development. In 1976, Walter Fiers at the University of Ghent was the first to establish the complete sequence of a viral RNA-genome. The next year Fred Sanger completed the first DNA-genome sequence, Phage Φ-X174, the first genome sequence for an archaeon, Methanococcus jannaschii, was completed in 1996, again by The Institute for Genomic Research. The development of new technologies has made it easier and cheaper to do sequencing. The US National Institutes of Health maintains one of several databases of genomic information. Among the thousands of completed genome sequencing projects include those for rice, a mouse, the plant Arabidopsis thaliana, the fish. In December 2013, scientists first sequenced the genome of a Neanderthal. The genome was extracted from the toe bone of a 130, new sequencing technologies, such as massive parallel sequencing have also opened up the prospect of personal genome sequencing as a diagnostic tool, as pioneered by Manteia Predictive Medicine. A major step toward that goal was the completion in 2007 of the genome of James D. Watson
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Evolution
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Evolution is change in the heritable characteristics of biological populations over successive generations. Evolutionary processes give rise to biodiversity at every level of organisation, including the levels of species, individual organisms. In July 2016, scientists reported identifying a set of 355 genes from the LUCA of all living on Earth. The fossil record includes a progression from early biogenic graphite, to microbial mat fossils, existing patterns of biodiversity have been shaped both by speciation and by extinction. More than 99 percent of all species that lived on Earth are estimated to be extinct. Estimates of Earths current species range from 10 to 14 million, more recently, in May 2016, scientists reported that 1 trillion species are estimated to be on Earth currently with only one-thousandth of one percent described. In the mid-19th century, Charles Darwin formulated the theory of evolution by natural selection. This teleonomy is the quality whereby the process of natural selection creates and preserves traits that are fitted for the functional roles they perform. The processes by which the changes occur, from one generation to another, are called evolutionary processes or mechanisms, the four most widely recognized evolutionary processes are natural selection, genetic drift, mutation and gene migration. Natural selection and genetic drift sort variation, mutation and gene migration create variation, consequences of selection can include meiotic drive, nonrandom mating and genetic hitchhiking. In the early 20th century the modern evolutionary synthesis integrated classical genetics with Darwins theory of evolution by natural selection through the discipline of population genetics, the importance of natural selection as a cause of evolution was accepted into other branches of biology. Moreover, previously held notions about evolution, such as orthogenesis, evolutionism, evolutionary computation, a sub-field of artificial intelligence, involves the application of Darwinian principles to problems in computer science. The proposal that one type of organism could descend from another type goes back to some of the first pre-Socratic Greek philosophers, such as Anaximander, such proposals survived into Roman times. The poet and philosopher Lucretius followed Empedocles in his masterwork De rerum natura, in contrast to these materialistic views, Aristotelianism considered all natural things as actualisations of fixed natural possibilities, known as forms. This was part of a teleological understanding of nature in which all things have an intended role to play in a divine cosmic order. In the 17th century, the new method of modern science rejected the Aristotelian approach, however, this new approach was slow to take root in the biological sciences, the last bastion of the concept of fixed natural types. The biological classification introduced by Carl Linnaeus in 1735 explicitly recognized the nature of species relationships. Other naturalists of this time speculated on the change of species over time according to natural laws
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Peter Simon Pallas
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Peter Simon Pallas was a German zoologist and botanist who worked in Russia. Pallas was born in Berlin, the son of Professor of Surgery Simon Pallas and he studied with private tutors and took an interest in natural history, later attending the University of Halle and the University of Göttingen. In 1760, he moved to the University of Leiden and passed his doctors degree at the age of 19, Pallas traveled throughout the Netherlands and to London, improving his medical and surgical knowledge. He then settled at The Hague, and his new system of classification was praised by Georges Cuvier. Pallas wrote Miscellanea Zoologica, which included descriptions of several new to science which he had discovered in the Dutch museum collections. A planned voyage to southern Africa and the East Indies fell through when his father recalled him to Berlin, there, he began work on his Spicilegia Zoologica. He explored the Caspian Sea, the Ural and Altai Mountains, the regular reports which Pallas sent to St Petersburg were collected and published as Reise durch verschiedene Provinzen des Russischen Reichs. They covered a range of topics, including geology and mineralogy, reports on the native peoples and their religions. In 1776, Pallas was elected a member of the Royal Swedish Academy of Sciences. Pallas settled in St Petersburg, becoming a favourite of Catherine II and teaching history to the Grand Dukes Alexander. He was provided with the plants collected by other naturalists to compile the Flora Rossica, a Russian flora, and started work on his Zoographica Rosso-Asiatica and he also published an account of Johann Anton Güldenstädts travels in the Caucasus. The Empress bought Pallass large natural history collection for 2,000 rubles,500 more than his asking price, during this period, Pallas helped plan the Mulovsky expedition, which was cancelled in October 1787. Between 1793 and 1794, Pallas led an expedition to southern Russia, visiting the Crimea. He was accompanied by his daughter and his new wife, an artist, servants, in February 1793, they travelled to Saratov and then downriver to Tsaritsyn. They spent the spring exploring the country to the east, and in August travelled along the banks of the Caspian Sea, in September, they travelled to the Crimea, wintering in Simferopol. Pallas spent the spring of 1794 exploring to the southeast, and in July travelled up the valley of the Dnieper, Pallas gave his account of the journey in his P. S. Pallas Bemerkungen auf einer Reise in die Südlichen Statthalterschaften des Russischen Reichs. Catherine II gave him an estate at Simferopol, where Pallas lived until the death of his second wife in 1810. He was then granted permission to leave Russia by Emperor Alexander, and returned to Berlin and his grave is preserved in the Protestant Friedhof I der Jerusalems- und Neuen Kirchengemeinde in Berlin-Kreuzberg, south of Hallesches Tor
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Mollusca
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The molluscs compose the large phylum Mollusca of invertebrate animals. Around 85,000 extant species of molluscs are recognized, molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats and they are highly diverse, not just in size and in anatomical structure, but also in behaviour and in habitat. The phylum is divided into 9 or 10 taxonomic classes. The gastropods are by far the most numerous molluscs in terms of classified species, the three most universal features defining modern molluscs are a mantle with a significant cavity used for breathing and excretion, the presence of a radula, and the structure of the nervous system. Other than these things, molluscs express great morphological diversity, so many textbooks base their descriptions on an ancestral mollusc. This has a single, limpet-like shell on top, which is made of proteins and chitin reinforced with calcium carbonate, the underside of the animal consists of a single muscular foot. Although molluscs are coelomates, the coelom tends to be small, the main body cavity is a hemocoel through which blood circulates, their circulatory systems are mainly open. The generalized mollusc has two paired nerve cords, or three in bivalves, the brain, in species that have one, encircles the esophagus. Most molluscs have eyes, and all have sensors to detect chemicals, vibrations, the simplest type of molluscan reproductive system relies on external fertilization, but more complex variations occur. All produce eggs, from which may emerge trochophore larvae, more complex veliger larvae, good evidence exists for the appearance of gastropods, cephalopods and bivalves in the Cambrian period 541 to 485.4 million years ago. Molluscs have, for centuries, also been the source of important luxury goods, notably pearls, mother of pearl, Tyrian purple dye and their shells have also been used as money in some preindustrial societies. Mollusc species can also represent hazards or pests for human activities, the bite of the blue-ringed octopus is often fatal, and that of Octopus apollyon causes inflammation that can last for over a month. Stings from a few species of large tropical cone shells can also kill, schistosomiasis is transmitted to humans via water snail hosts, and affects about 200 million people. Snails and slugs can also be serious pests, and accidental or deliberate introduction of some snail species into new environments has seriously damaged some ecosystems. The words mollusc and mollusk are both derived from the French mollusque, which originated from the Latin molluscus, from mollis, molluscus was itself an adaptation of Aristotles τα μαλακά, the soft things, which he applied to cuttlefish. The scientific study of molluscs is accordingly called malacology, as it is now known these groups have no relation to molluscs, and very little to one another, the name Molluscoida has been abandoned. The most universal features of the structure of molluscs are a mantle with a significant cavity used for breathing and excretion
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Limax
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Limax is a genus of air-breathing land slugs in the terrestrial pulmonate gastropod mollusk family Limacidae. The generic name Limax literally means slug, some species, such as the leopard slug and the tawny garden slug, are considered serious garden pests. The genus Limax sensu stricto is probably monophyletic and this genus is native to Europe, but at least one species has been introduced into North America
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Hagfish
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Hagfish, the class Myxini, are eel-shaped, slime-producing marine fish. They are the known living animals that have a skull. Along with lampreys, hagfish are jawless, they are the group to vertebrates. The classification of hagfish has been controversial, the issue is whether the hagfish is a degenerate type of vertebrate-fish, or represents a stage that precedes the evolution of the vertebral column. The original scheme groups hagfish and lampreys together as cyclostomes, as the oldest surviving class of vertebrates alongside gnathostomes, an alternative scheme proposed that jawed vertebrates are more closely related to lampreys than to hagfish, and introduces the category craniata to group vertebrates near hagfish. Recent DNA evidence has supported the original scheme, Hagfish average about 0.5 m in length. The largest known species is Eptatretus goliath with a recorded at 127 cm, while Myxine kuoi. Hagfish have elongated, eel-like bodies, and paddle-like tails, the skin is naked and covers the body like a loosely fitting sock. They have cartilaginous skulls and tooth-like structures composed of keratin, colors depend on the species, ranging from pink to blue-grey, and black or white spots may be present. Eyes are simple eyespots, not compound eyes that can resolve images, Hagfish have no true fins and have six or eight barbels around the mouth and a single nostril. Instead of vertically articulating jaws like Gnathostomata, they have a pair of horizontally moving structures with tooth-like projections for pulling off food, the mouth of the hagfish has two pairs of horny, comb-shaped teeth on a cartilaginous plate that protracts and retracts. These teeth are used to food and draw it toward the pharynx. Hagfish are long and vermiform, and can exude copious quantities of a milky, the typical species Myxine glutinosa was named for this slime. When captured and held, e. g. by the tail, they secrete the microfibrous slime, which expands into up to 20 litres of sticky, gelatinous material when combined with water. This singular behavior may assist them in extricating themselves from the jaws of predatory fish or from the interior of their own prey, recently, the slime was reported to entrain water in its microfilaments, creating a slow-to-dissipate, viscoelastic substance, rather than a simple gel. It has been proven to impair the function of a predator fishs gills, in this case, the hagfishs mucus would clog up the predators gills, disabling their ability to breathe. The predator would release the hagfish as it focused less on eating and it is because of the mucus that there are very few marine predators that target the hagfish. The other known predators of hagfish are varieties of birds or mammals, free-swimming hagfish also slime when agitated and later clear the mucus off by way of the same travelling-knot behavior
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Lamprey
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Lampreys are any jawless fish of the order Petromyzontiformes, placed in the superclass Cyclostomata. The adult lamprey may be characterized by a toothed, funnel-like sucking mouth, the common name lamprey is probably derived from Latin lampetra, which may mean stone licker, though the etymology is uncertain. Currently there are about 38 known extant species of lampreys, parasitic species are the best known, and feed by boring into the flesh of other fish to suck their blood, but only 18 species of lampreys are parasitic. Adults of the species do not feed, they live off reserves acquired as ammocoetes. The lampreys are an ancient lineage of vertebrates, though their exact relationship to hagfishes. Adults superficially resemble eels in that they have scaleless, elongated bodies, lacking paired fins, adult lampreys have large eyes, one nostril on the top of the head, and seven gill pores on each side of the head. The pharynx is subdivided, the part forming a respiratory tube that is isolated from the mouth by a valve called the velum. Near the gills are the eyes, which are developed and buried under skin in the larvae. The eyes complete their development during metamorphosis, and in adults are covered by a thin, instead of true vertebrae, they have a series of cartilaginous structures called arcualia arranged above the notochord. Hagfish, which resemble lampreys, have traditionally considered the sister taxon of the true vertebrates. Studies have shown that lampreys are amongst the most energy-efficient swimmers and their swimming movements generate low-pressure zones around their body, which pull rather than push their bodies through the water. Parasitic lampreys feed on prey as adults by attaching their mouthparts to the animals body, then using their teeth to cut through surface tissues until they reach blood. A study of stomach content of some lampreys have also shown remains of intestines, fins, although attacks on humans do occur, they will generally not attack humans unless starved. Non-parasitic lampreys, which are freshwater species, do not feed as adults, they live off reserves acquired as ammocoetes. Lamprey leukocytes express surface variable lymphocyte receptors generated from somatic recombination of leucine-rich repeat gene segments in a recombination activating gene-independent manner, northern lampreys have the highest number of chromosomes among vertebrates. Pouched lamprey larvae also have a high tolerance for free iron in their bodies. Adult lampreys spawn in rivers and then die, the young larvae, ammocoetes, spend several years in the rivers, where they live burrowed in fine sediment, filter feeding on detritus and microorganisms. Then, ammocoetes undergo a metamorphosis lasting several months, some species do not feed after metamorphosis, while others migrate to the sea or lakes, where they feed on different species of fish and even on marine mammals
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