109-556: Sturgeon (from Old English styrġa ultimately from Proto-Indo-European * str̥(Hx)yón -) is the common name for the 28 species of fish belonging to the family Acipenseridae . The earliest sturgeon fossils date to the Late Cretaceous , and are descended from other, earlier acipenseriform fish , which date back to the Early Jurassic period, some 174 to 201 million years ago. They are one of two living families of
218-613: A definite article ("the"), a demonstrative adjective ("that"), and demonstrative pronoun . Other demonstratives are þēs ("this"), and ġeon ("that over there"). These words inflect for case, gender, and number. Adjectives have both strong and weak sets of endings, weak ones being used when a definite or possessive determiner is also present. Verbs conjugate for three persons : first, second, and third; two numbers: singular, plural; two tenses : present, and past; three moods : indicative , subjunctive , and imperative ; and are strong (exhibiting ablaut) or weak (exhibiting
327-928: A heterocercal caudal fin similar to those of sharks , and an elongated, spindle-like body that is smooth-skinned, scaleless, and armored with five lateral rows of bony plates called scutes . Several species can grow quite large, typically ranging 2–3.5 m (7–12 ft) in length. The largest sturgeon on record was a beluga female captured in the Volga Delta in 1827, measuring 7.2 m (23 ft 7 in) long and weighing 1,571 kg (3,463 lb). Most sturgeons are anadromous bottom-feeders , migrating upstream to spawn but spending most of their lives feeding in river deltas and estuaries . Some species inhabit freshwater environments exclusively, while others primarily inhabit marine environments near coastal areas, and are known to venture into open ocean. Several species of sturgeon are harvested for their roe , which
436-493: A zygote changes the surrounding membrane to not allow any more sperm to penetrate the egg, so multiple fertilizations can be prevented. Fusion of a zygote also activates the egg so it can begin undergoing cell division. Each animal species might not have specifically a sperm and an egg, but two gametes that contain half of the species' typical genetic material and the membranes of these gametes fuse to start creating an offspring. Not long after successful fertilization by sperm,
545-398: A back vowel ( /ɑ/ , /o/ , /u/ ) at the time of palatalization, as illustrated by the contrast between fisċ /fiʃ/ ('fish') and its plural fiscas /ˈfis.kɑs/ . But due to changes over time, a knowledge of the history of the word in question is needed to predict the pronunciation with certainty (for details, see palatalization ). In word-final position, the pronunciation of sċ
654-449: A blastocyst. Other species such as sea stars , frogs , chicks , and mice have all the same structures in this stage, yet the orientation of these features differs, plus these species have additional types of cells in this stage. After blastulation, the single-layered blastula expands and reorganizes into multiple layers, a gastrula (seen in the figure to the right). Reptiles , birds and mammals are triploblastic organisms, meaning
763-487: A butterfly. Adulthood is the stage of when physical and intellectual maturity have been achieved and this differs between species. In humans , adulthood is thought to be around 20 or 21 years old and is the longest stage of life, but in all species it ends with death. In dogs , small breeds (e.g., Yorkshire Terrier , Chihuahua , Cocker Spaniel , etc.) physically mature faster than large breeds (e.g., Saint Bernard , Great Dane , Golden Retriever , etc.), so adulthood
872-421: A cavity and fuse with the central canal of the neural tube. Secondary neurulation occurs in the small region starting at the spinal tail bud up to the posterior neuropore, which is the open neural folds near the tail region that don't close through primary neurulation. As canalization progresses over the next few weeks, neurons and ependymal cells (cells that create cerebral spinal fluid ) differentiate to become
981-452: A cluster of nerve bodies positioned along the spinal cord at the dorsal and ventral roots of a spinal nerve, which is a pair of nerves that correspond to a vertebra of the spine. In secondary neurulation, caudal and sacral regions of the spine are formed after primary neurulation is finished. This process initiates once primary neurulation is finished and the posterior neuropore closes, so the tail bud can proliferate and condense, then create
1090-556: A combination of habitat destruction , overfishing, and pollution. No species is known to naturally occur south of the equator, though attempts at sturgeon aquaculture are being made in Uruguay , South Africa , and other places. Most species are at least partially anadromous , spawning in fresh water and feeding in nutrient-rich, brackish waters of estuaries or undergoing significant migrations along coastlines. However, some species have evolved purely freshwater existences, such as
1199-406: A dental suffix). Verbs have two infinitive forms: bare and bound; and two participles : present and past. The subjunctive has past and present forms. Finite verbs agree with subjects in person and number. The future tense , passive voice , and other aspects are formed with compounds. Adpositions are mostly before but are often after their object. If the object of an adposition is marked in
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#17327724349481308-551: A derived one; sturgeon ancestors had bony skeletons. They also lack vertebral centra , and are partially covered with five lateral rows of scutes rather than scales . They also have four barbels —sensory organs that precede their wide, toothless mouths. They navigate their riverine habitats traveling just off the bottom with their barbels dragging along gravel, or murky substrate. Sturgeon are recognizable for their elongated bodies, flattened rostra , distinctive scutes and barbels, and elongated upper tail lobes. The skeletal support for
1417-517: A following ⟨m⟩ or ⟨n⟩ . Modern editions of Old English manuscripts generally introduce some additional conventions. The modern forms of Latin letters are used, including ⟨g⟩ instead of insular G , ⟨s⟩ instead of insular S and long S , and others which may differ considerably from the insular script, notably ⟨e⟩ , ⟨f⟩ and ⟨r⟩ . Macrons are used to indicate long vowels, where usually no distinction
1526-467: A friction that led to the erosion of the complicated inflectional word endings. Simeon Potter notes: No less far-reaching was the influence of Scandinavian upon the inflexional endings of English in hastening that wearing away and leveling of grammatical forms which gradually spread from north to south. It was, after all, a salutary influence. The gain was greater than the loss. There was a gain in directness, in clarity, and in strength. The strength of
1635-427: A hollow sphere of cells, which is a blastula . These outer cells form a single epithelial layer, the blastoderm, that essentially encases the fluid-filled inside that is the blastocoel. The figure to the right shows the basic process that is modified in different species. Blastulation differs slightly in different species, but in mammals, the eight-cell stage embryo forms into a slightly different type of blastula, called
1744-403: A larval form of an animal is the caterpillar of butterflies and moths . Caterpillars keep growing and feeding in order for enough energy during the pupal stage, when necessary body parts for metamorphosis are grown. The juvenile phase is different in plants and animals, but in plants juvenility is an early phase of plant growth in which plants can't flower. In animals, the juvenile stage
1853-490: A parallel manner but branch off to develop more specific features for the organism such as hooves, a tail, or ears. In developing vertebrate offspring, a neural tube is formed through either primary or secondary neurulation . Some species develop their spine and nervous system using both primary and secondary neurulation, while others use only primary or secondary neurulation. In human fetal development, primary neurulation occurs during weeks 3 and 4 of gestation to develop
1962-530: A period of 700 years, from the Anglo-Saxon settlement of Britain in the 5th century to the late 11th century, some time after the Norman invasion . While indicating that the establishment of dates is an arbitrary process, Albert Baugh dates Old English from 450 to 1150, a period of full inflections, a synthetic language . Perhaps around 85% of Old English words are no longer in use, but those that survived are
2071-544: A sister to A. dabryanus . The family contains 8 extinct fossil species and 28 extant species/subspecies (include 1 species of Sterlet and 2 species of living fossils), in 4 genera. This list uses the original classification scheme: Family Acipenseridae Sturgeon range from subtropical to subarctic waters in North America and Eurasia . In North America , they range along the Atlantic Coast from
2180-455: A slightly different journey through these stages, since some stages might be shorter or longer when compared to other species, and where the offspring develops is different for each animal type (e.g., in a hard egg shell, uterus, soft egg shell, on a plant leaf, etc.). In humans, the process of fetal development starts after sperm fertilizes an egg and they fuse together, kickstarting embryonic development . The fusion of egg and sperm into
2289-414: Is metamorphosis . For example, amphibian tadpoles have a maturation of liver enzymes, hemoglobin , and eye pigments, in addition to their nervous, digestive, and reproductive systems being remodeled. In all species, molting and juvenile hormones appear to regulate these changes. The figure to the right shows the stages of life in butterflies and their metamorphosis transforms the caterpillar into
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#17327724349482398-552: Is also sparse early Northumbrian evidence of a sixth case: the locative . The evidence comes from Northumbrian Runic texts (e.g., ᚩᚾ ᚱᚩᛞᛁ on rodi "on the Cross"). Adjectives agree with nouns in case, gender, and number, and can be either strong or weak. Pronouns and sometimes participles agree in case, gender, and number. First-person and second- person personal pronouns occasionally distinguish dual-number forms. The definite article sē and its inflections serve as
2507-422: Is as follows. The sounds enclosed in parentheses in the chart above are not considered to be phonemes : The above system is largely similar to that of Modern English , except that [ç, x, ɣ, l̥, n̥, r̥] (and [ʍ] for most speakers ) have generally been lost, while the voiced affricate and fricatives (now also including /ʒ/ ) have become independent phonemes, as has /ŋ/ . The open back rounded vowel [ɒ]
2616-416: Is discontinuous and can start at different points along the cranial-caudal axis necessary for it to close. After the neural crest closes, the neural crest cells and ectoderm cells separate and the ectoderm becomes the epidermis surrounding this complex. The neural crest cells differentiate to become components of most of the peripheral nervous system in animals. Next, the notochord degenerates to become only
2725-621: Is evidenced by the continued variation between their successors in Middle and Modern English. In fact, what would become the standard forms of Middle English and of Modern English are descended from Mercian rather than West Saxon, while Scots developed from the Northumbrian dialect. It was once claimed that, owing to its position at the heart of the Kingdom of Wessex, the relics of Anglo-Saxon accent, idiom and vocabulary were best preserved in
2834-668: Is followed by Middle English (1150 to 1500), Early Modern English (1500 to 1650) and finally Modern English (after 1650), and in Scotland Early Scots (before 1450), Middle Scots ( c. 1450 to 1700) and Modern Scots (after 1700). Just as Modern English is not monolithic, Old English varied according to place. Despite the diversity of language of the Germanic-speaking migrants who established Old English in England and southeastern Scotland, it
2943-523: Is most commonly found in social mammals, such as wild dogs , monkeys , apes , lions , wolves , and more. In humans, puberty marks the end of this stage and adolescence follows. Some species begin puberty and reproduction before the juvenile stage is over, such as in female non-human primates. The larval and pupal stages can be seen in the figure to the right. The process of an organism's body undergoing structural and physical changes after birth or hatching to become suitable for its adult environment
3052-835: Is much freer. The oldest Old English inscriptions were written using a runic system , but from about the 8th century this was replaced by a version of the Latin alphabet . Englisċ , from which the word English is derived, means 'pertaining to the Angles '. The Angles were one of the Germanic tribes who settled in many parts of Britain in the 5th century. By the 9th century, all speakers of Old English, including those who claimed Saxon or Jutish ancestry, could be referred to as Englisċ . This name probably either derives from Proto-Germanic *anguz , which referred to narrowness, constriction or anxiety, perhaps referring to shallow waters near
3161-864: Is possible to reconstruct proto-Old English as a fairly unitary language. For the most part, the differences between the attested regional dialects of Old English developed within England and southeastern Scotland, rather than on the Mainland of Europe. Although from the tenth century Old English writing from all regions tended to conform to a written standard based on Late West Saxon, in speech Old English continued to exhibit much local and regional variation, which remained in Middle English and to some extent Modern English dialects . The four main dialectal forms of Old English were Mercian , Northumbrian , Kentish , and West Saxon . Mercian and Northumbrian are together referred to as Anglian . In terms of geography
3270-454: Is processed into the luxury food caviar . This has led to serious overexploitation , which combined with other conservation threats, has brought most of the species to critically endangered status, at the edge of extinction . Acipenseriform fishes appeared in the fossil record some 174 to 201 million years ago by Nathan, during the Early Jurassic , making them some of the earliest extant actinopterygian fishes. True sturgeons appear in
3379-424: Is reached anywhere from 12 to 24 months or 1 to 2 years. In contrast, many insect species have long larval stages and the adult stage is only for reproduction. The silkworm moths don't have mouthparts and don't feed, so they have to consume enough food during the larval stage for energy to survive and mate. Senescence is when cells stop dividing but don't die, but these cells can build up and cause problems in
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3488-434: Is replaced by ⟨þ⟩ ). In contrast with Modern English orthography , Old English spelling was reasonably regular , with a mostly predictable correspondence between letters and phonemes . There were not usually any silent letters —in the word cniht , for example, both the ⟨c⟩ and ⟨h⟩ were pronounced ( /knixt ~ kniçt/ ) unlike the ⟨k⟩ and ⟨gh⟩ in
3597-507: Is the peculiar ability of sturgeons to produce reproductively viable hybrids , even between species assigned to different genera . While ray-finned fishes (Actinopterygii) have a long evolutionary history culminating in the most familiar fishes, past adaptive evolutionary radiations have left only a few survivors, such as sturgeons and gars . The wide range of the acipenserids and their endangered status have made collection of systematic materials difficult. The factors have led researchers in
3706-613: Is used in anthropology as "the process through which each of us embodies the history of our own making". The word ontogeny comes from the Greek on meaning a being, individual; and existence, and from the suffix -geny from the Greek - geniea , meaning genesis, origin, and mode of production. The term ontogeny was coined by Ernst Haeckel , a German zoologist and evolutionist in the 1860s. Haeckel, born in Germany on February 16, 1834,
3815-882: The Black , Azov , and Caspian Seas ( Danube , Dnepr , Volga , Ural and Don ); the north-flowing rivers of Russia that feed the Arctic Ocean ( Ob , Yenisei , Lena , Kolyma ); in the rivers of Central Asia ( Amu Darya and Syr Darya ) and Lake Baikal . In the Pacific Ocean, they are found in the Amur River along the Russian- Chinese border, on Sakhalin Island, and some rivers in northeast China. Throughout this extensive range, almost all species are highly threatened or vulnerable to extinction due to
3924-815: The Gulf of Mexico to Newfoundland , including the Great Lakes and the St. Lawrence , Missouri , and Mississippi Rivers, as well as along the West Coast in major rivers from California and Idaho to British Columbia . They occur along the European Atlantic coast, including the Mediterranean basin, especially in the Adriatic Sea and the rivers of North Italy ; in the rivers that flow into
4033-652: The Latin alphabet was introduced and adapted for the writing of Old English , replacing the earlier runic system. Nonetheless, the largest transfer of Latin-based (mainly Old French ) words into English occurred after the Norman Conquest of 1066, and thus in the Middle English rather than the Old English period. Another source of loanwords was Old Norse , which came into contact with Old English via
4142-603: The dialect of Somerset . For details of the sound differences between the dialects, see Phonological history of Old English § Dialects . The language of the Anglo-Saxon settlers appears not to have been significantly affected by the native British Celtic languages which it largely displaced . The number of Celtic loanwords introduced into the language is very small, although dialect and toponymic terms are more often retained in western language contact zones (Cumbria, Devon, Welsh Marches and Borders and so on) than in
4251-560: The ectoderm is the outer layer of cells that become the epidermis and hair while being the precursor to the mammary glands, central nervous system , and the peripheral nervous systems . The figure above shows how the development of a pig , cow , rabbit , and human offspring are similar when compared to one another. This figure shows how the germ layers can become different organs and tissues in evolutionarily higher life-forms and how these species essentially develop very similarly. Additionally, it shows how multiple species develop in
4360-456: The egg to adult. The term can also be used to refer to the study of the entirety of an organism's lifespan. Ontogeny is the developmental history of an organism within its own lifetime, as distinct from phylogeny , which refers to the evolutionary history of a species. Another way to think of ontogeny is that it is the process of an organism going through all of the developmental stages over its lifetime. The developmental history includes all
4469-609: The kingdom of Northumbria . Other parts of the island continued to use Celtic languages ( Gaelic – and perhaps some Pictish – in most of Scotland, Medieval Cornish all over Cornwall and in adjacent parts of Devon , Cumbric perhaps to the 12th century in parts of Cumbria , and Welsh in Wales and possibly also on the English side of the Anglo-Welsh border ); except in the areas of Scandinavian settlements, where Old Norse
Sturgeon - Misplaced Pages Continue
4578-564: The lake sturgeon ( Acipenser fulvescens ) and the Baikal sturgeon ( A. baerii baicalensis ), or have been forced into them by human or natural impoundment of their native rivers, as in the case of some subpopulations of white sturgeon ( A. transmontanus ) in the Columbia River and Siberian sturgeon ( A. baerii ) in the Ob basin. Sturgeons retain several primitive characteristics from
4687-402: The nucleus pulposus of the intervertebral discs and the mesoderm cells differentiate to become the somites and skeletal muscle later on. Also during this stage, the neural crest cells become the spinal ganglions, which function as the brain in organisms like earthworms and arthropods . In more advanced organisms like amphibians , birds and mammals ; the spinal ganglions consists of
4796-422: The 8th century, the runic system came to be supplanted by a (minuscule) half-uncial script of the Latin alphabet introduced by Irish Christian missionaries. This was replaced by Insular script , a cursive and pointed version of the half-uncial script. This was used until the end of the 12th century when continental Carolingian minuscule (also known as Caroline ) replaced the insular. The Latin alphabet of
4905-871: The Acipenseriformes alongside paddlefish (Polyodontidae). The family is grouped into four genera: Acipenser (which is paraphyletic , containing many distantly related sturgeon species), Huso , Scaphirhynchus , and Pseudoscaphirhynchus . Two species ( A. naccarii and A. dabryanus ) may be extinct in the wild , and one ( P. fedtschenkoi ) may be entirely extinct. Sturgeons are native to subtropical, temperate and sub-Arctic rivers, lakes and coastlines of Eurasia and North America . A Maastrichtian -age fossil found in Morocco shows that they also once lived in Africa . Sturgeons are long-lived, late-maturing fishes with distinctive characteristics, such as
5014-523: The English language was heavily influenced by Anglo-Norman, developing into what is now known as Middle English in England and Early Scots in Scotland. Old English developed from a set of Anglo-Frisian or Ingvaeonic dialects originally spoken by Germanic tribes traditionally known as the Angles , Saxons and Jutes . As the Germanic settlers became dominant in England, their language replaced
5123-406: The English language; some of them, such as Pope Gregory I 's treatise Pastoral Care , appear to have been translated by Alfred himself. In Old English, typical of the development of literature, poetry arose before prose, but Alfred chiefly inspired the growth of prose. A later literary standard, dating from the late 10th century, arose under the influence of Bishop Æthelwold of Winchester , and
5232-608: The Great . From that time on, the West Saxon dialect (then in the form now known as Early West Saxon) became standardised as the language of government, and as the basis for the many works of literature and religious materials produced or translated from Latin in that period. The later literary standard known as Late West Saxon (see History , above), although centred in the same region of the country, appears not to have been directly descended from Alfred's Early West Saxon. For example,
5341-410: The Northumbrian dialect retained /i(ː)o̯/ , which had merged with /e(ː)o̯/ in West Saxon. For more on dialectal differences, see Phonological history of Old English (dialects) . Some of the principal sound changes occurring in the pre-history and history of Old English were the following: For more details of these processes, see the main article, linked above. For sound changes before and after
5450-880: The Northumbrian region lay north of the Humber River; the Mercian lay north of the Thames and south of the Humber River; West Saxon lay south and southwest of the Thames; and the smallest, Kentish region lay southeast of the Thames, a small corner of England. The Kentish region, settled by the Jutes from Jutland, has the scantest literary remains. The term West Saxon actually is represented by two different dialects: Early West Saxon and Late West Saxon. Hogg has suggested that these two dialects would be more appropriately named Alfredian Saxon and Æthelwoldian Saxon, respectively, so that
5559-467: The Old English period is also often attributed to Norse influence. The influence of Old Norse certainly helped move English from a synthetic language along the continuum to a more analytic word order , and Old Norse most likely made a greater impact on the English language than any other language. The eagerness of Vikings in the Danelaw to communicate with their Anglo-Saxon neighbours produced
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#17327724349485668-478: The Old English period, see Phonological history of English . Nouns decline for five cases : nominative , accusative , genitive , dative , instrumental ; three genders : masculine, feminine, neuter; and two numbers : singular, and plural; and are strong or weak. The instrumental is vestigial and only used with the masculine and neuter singular and often replaced by the dative . Only pronouns and strong adjectives retain separate instrumental forms. There
5777-526: The Scandinavian rulers and settlers in the Danelaw from the late 9th century, and during the rule of Cnut and other Danish kings in the early 11th century. Many place names in eastern and northern England are of Scandinavian origin. Norse borrowings are relatively rare in Old English literature, being mostly terms relating to government and administration. The literary standard, however,
5886-606: The Viking influence on Old English appears from the fact that the indispensable elements of the language – pronouns , modals , comparatives , pronominal adverbs (like hence and together ), conjunctions and prepositions – show the most marked Danish influence; the best evidence of Scandinavian influence appears in the extensive word borrowings because, as Jespersen indicates, no texts exist in either Scandinavia or Northern England from this time to give certain evidence of an influence on syntax. The effect of Old Norse on Old English
5995-580: The abundance of prey items in the benthic environment. They do, however, still share several primitive characteristics, such as heterocercal tail, reduced squamation, more fin rays than supporting bony elements, and unique jaw suspension. Despite the existence of a fossil record, full classification and phylogeny of the sturgeon species has been difficult to determine, in part due to the high individual and ontogenic variation, including geographical clines in certain features, such as rostrum shape, number of scutes, and body length. A further confounding factor
6104-506: The basic elements of Modern English vocabulary. Old English is a West Germanic language , and developed out of Ingvaeonic (also known as North Sea Germanic) dialects from the 5th century. It came to be spoken over most of the territory of the Anglo-Saxon kingdoms which became the Kingdom of England . This included most of present-day England, as well as part of what is now southeastern Scotland , which for several centuries belonged to
6213-559: The beginnings of the compound tenses of Modern English . Old English verbs include strong verbs , which form the past tense by altering the root vowel, and weak verbs , which use a suffix such as -de . As in Modern English, and peculiar to the Germanic languages, the verbs formed two great classes: weak (regular), and strong (irregular). Like today, Old English had fewer strong verbs, and many of these have over time decayed into weak forms. Then, as now, dental suffixes indicated
6322-494: The body. These cells can release substances that cause inflammation and can damage healthy nearby cells. Senescence can be induced by un-repaired DNA damage (e.g., from radiation, old age, etc.) or other cellular stress and also is the state of being old. Most organisms undergo allometric changes in shape as they grow and mature , while others engage in metamorphosis . Even reptiles (non-avian sauropsids, e.g., crocodilians , turtles , snakes , and lizards ), in which
6431-399: The bony fishes. Along with other members of the subclass Chondrostei , they are unique among bony fishes because their skeletons are almost entirely cartilaginous . To maintain structure, sturgeons are one of few organisms to retain a post-embryonic notochord that acts like a soft spine running through the body. Notably, however, the cartilaginous skeleton is not a primitive character, but
6540-494: The borrowing of individual Latin words based on which patterns of sound change they have undergone. Some Latin words had already been borrowed into the Germanic languages before the ancestral Angles and Saxons left continental Europe for Britain. More entered the language when the Anglo-Saxons were converted to Christianity and Latin-speaking priests became influential. It was also through Irish Christian missionaries that
6649-400: The brain and spinal cord. Then during weeks 5 and 6 of gestation, secondary neurulation forms the lower sacral and coccygeal cord. The diagram to the right illustrates primary neurulation, which is the process of cells surrounding the neural plate interacting with neural plate cells to proliferate, converge, and pinch off to form a hollow tube above the notochord and mesoderm. This process
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#17327724349486758-414: The change of behavioral machinery during development was distinct from the change in behavior during development. We can conclude that the thrush itself, i.e. its behavioral machinery, has changed only if the behavior change occurred while the environment was held constant...When we turn from description to causal analysis, and ask in what way the observed change in behavior machinery has been brought about,
6867-442: The class Actinopterygii and the order Acipenseriformes are both clades . The family Acipenseridae is subdivided into 2 subfamilies; Acipenserinae , including the genera Acipenser and Huso , and Scaphirhynchinae , including the genera Scaphirhynchus and Pseudoscaphirhynchus . However, multiple recent studies have recovered this arrangement as paraphyletic , instead finding A. oxyrhinchus and A. sturio to form
6976-499: The cluster ending in the palatal affricate is sometimes written ⟨nċġ⟩ (or ⟨nġċ⟩ ) by modern editors. Between vowels in the middle of a word, the pronunciation can be either a palatalized geminate /ʃː/ , as in fisċere /ˈfiʃ.ʃe.re/ ('fisherman') and wȳsċan , /ˈwyːʃ.ʃɑn 'to wish'), or an unpalatalized consonant sequence /sk/ , as in āscian /ˈɑːs.ki.ɑn/ ('to ask'). The pronunciation /sk/ occurs when ⟨sc⟩ had been followed by
7085-461: The coast, or else it may derive from a related word *angô which could refer to curve or hook shapes including fishing hooks. Concerning the second option, it has been hypothesised that the Angles acquired their name either because they lived on a curved promontory of land shaped like a fishhook , or else because they were fishermen (anglers). Old English was not static, and its usage covered
7194-421: The dative case, an adposition may conceivably be located anywhere in the sentence. Remnants of the Old English case system in Modern English are in the forms of a few pronouns (such as I/me/mine , she/her , who/whom/whose ) and in the possessive ending -'s , which derives from the masculine and neuter genitive ending -es . The modern English plural ending -(e)s derives from the Old English -as , but
7303-407: The developing organism have been established. He proposed that individual development followed developmental stages of previous generations and that the future generations would add something new to this process, and that there was a causal parallelism between an animal's ontogeny and phylogeny. In addition, Haeckel suggested a biogenetic law that ontogeny recapitulates phylogeny, based on the idea that
7412-458: The development of form and shape of an organism; tissue growth; and cellular differentiation . The term ontogeny has also been used in cell biology to describe the development of various cell types within an organism. Ontogeny is a useful field of study in many disciplines, including developmental biology , cell biology , genetics , developmental psychology , developmental cognitive neuroscience , and developmental psychobiology . Ontogeny
7521-737: The developmental events that occur during the existence of an organism, beginning with the changes in the egg at the time of fertilization and events from the time of birth or hatching and afterward (i.e., growth, remolding of body shape, development of secondary sexual characteristics, etc.). While developmental (i.e., ontogenetic) processes can influence subsequent evolutionary (e.g., phylogenetic) processes (see evolutionary developmental biology and recapitulation theory ), individual organisms develop (ontogeny), while species evolve (phylogeny). Ontogeny, embryology and developmental biology are closely related studies and those terms are sometimes used interchangeably. Aspects of ontogeny are morphogenesis ,
7630-447: The digestive system and the lungs. The mesoderm gives rise to other tissues not formed by the ectoderm, such as the heart, muscles, bones, blood, dermis of the skin, bone marrow, and the urogenital system. This germ layer is more specific for species, as it is the distinguishing layer of the three that can identify evolutionarily higher life-forms (e.g., bilateral organisms like humans) from lower-life forms (with radial symmetry). Lastly,
7739-431: The east. However, various suggestions have been made concerning possible influence that Celtic may have had on developments in English syntax in the post–Old English period, such as the regular progressive construction and analytic word order , as well as the eventual development of the periphrastic auxiliary verb do . These ideas have generally not received widespread support from linguists, particularly as many of
7848-459: The exact relationships of the members of the most derived , primarily Atlantic clade vary, although most analyses at least find all the species in it to form a monophyletic clade. The placement of A. sinensis also varies by the study, with some placing it as the only Pacific member of the otherwise Atlantic-based most-derived clade, whereas others place it with the rest of the Pacific sturgeons as
7957-433: The figure below, human germ cells are able to differentiate into the specific organs and tissues they become later on in life. Germ cells are able to migrate to their final locations to rearrange themselves and some organs are made of two germ layers; one for the outside, the other for the inside. The endoderm cells become the internal linings of organisms, such as the stomach, colon, small intestine, liver, and pancreas of
8066-645: The former diphthong /iy/ tended to become monophthongised to /i/ in EWS, but to /y/ in LWS. Due to the centralisation of power and the destruction wrought by Viking invasions, there is relatively little written record of the non-West Saxon dialects after Alfred's unification. Some Mercian texts continued to be written, however, and the influence of Mercian is apparent in some of the translations produced under Alfred's programme, many of which were produced by Mercian scholars. Other dialects certainly continued to be spoken, as
8175-681: The fossil record during the Upper Cretaceous , with amongst the oldest known remains being a partial skull from the Cenomanian (100–94 million years ago) of Alberta, Canada. In that time, sturgeons have undergone remarkably little morphological change, indicating their evolution has been exceptionally slow and earning them informal status as living fossils . This is explained in part by the long generation interval, tolerance for wide ranges of temperature and salinity , lack of predators due to size and bony plated armor, or scutes, and
8284-531: The futhorc. A few letter pairs were used as digraphs , representing a single sound. Also used was the Tironian note ⟨⁊⟩ (a character similar to the digit 7) for the conjunction and . A common scribal abbreviation was a thorn with a stroke ⟨ꝥ⟩ , which was used for the pronoun þæt ( that ). Macrons over vowels were originally used not to mark long vowels (as in modern editions), but to indicate stress, or as abbreviations for
8393-502: The gastrula comprises three germ layers ; the endoderm (inner layer), mesoderm (middle layer), and ectoderm (outer layer). As seen in the figure below, each germ layer will become multi-potent stem cells that can become a specific tissue depending on the germ layer and is what happens in humans. This differentiation of germ layers differs slightly, because not all of the organs and tissues below are in all organisms, but corresponding body systems can be substituted in place of these. In
8502-443: The hereditary modification of embryonic development. Marine biologist Walter Garstang reversed Haeckel's relationship between ontogeny and phylogeny, stating that ontogeny creates phylogeny, not recapitulates it. A seminal 1963 paper by Nikolaas Tinbergen named ontogeny as one of the four primary questions of biology, along with Julian Huxley's three others: causation, survival value and evolution. Tinbergen emphasized that
8611-603: The inscriptions on the Franks Casket ) date to the early 8th century. The Old English Latin alphabet was introduced around the 8th century. With the unification of several of the Anglo-Saxon kingdoms (outside the Danelaw ) by Alfred the Great in the later 9th century, the language of government and literature became standardised around the West Saxon dialect (Early West Saxon). Alfred advocated education in English alongside Latin, and had many works translated into
8720-416: The languages brought to Great Britain by Anglo-Saxon settlers in the mid-5th century, and the first Old English literary works date from the mid-7th century. After the Norman Conquest of 1066, English was replaced for several centuries by Anglo-Norman (a type of French ) as the language of the upper classes. This is regarded as marking the end of the Old English era, since during the subsequent period
8829-601: The languages of Roman Britain : Common Brittonic , a Celtic language ; and Latin , brought to Britain by the Roman conquest . Old English had four main dialects, associated with particular Anglo-Saxon kingdoms : Kentish , Mercian , Northumbrian , and West Saxon . It was West Saxon that formed the basis for the literary standard of the later Old English period, although the dominant forms of Middle and Modern English would develop mainly from Mercian, and Scots from Northumbrian. The speech of eastern and northern parts of England
8938-449: The latter applied only to "strong" masculine nouns in the nominative and accusative cases; different plural endings were used in other instances. Old English nouns had grammatical gender , while modern English has only natural gender. Pronoun usage could reflect either natural or grammatical gender when those conflicted, as in the case of ƿīf , a neuter noun referring to a female person. In Old English's verbal compound constructions are
9047-438: The lumbar and tail vertebrae of frogs and chicks and in both instances, this process is like a continuation of gastrulation. In most species, the young organism that is just born or hatched is not sexually mature yet and in most animals, this young organism looks quite different than the adult form. This young organism is the larva and is the intermediate form before metamorphosing into an adult. A well known example of
9156-456: The modern knight ( /naɪt/ ). The following table lists the Old English letters and digraphs together with the phonemes they represent, using the same notation as in the Phonology section above. After /n/ , /j/ was realized as [dʒ] and /ɣ/ was realized as [ɡ] . The spellings ⟨ncg⟩ , ⟨ngc⟩ and even ⟨ncgg⟩ were occasionally used instead of
9265-1247: The most basal clade among sturgeons, and all other species being in a separate clade, with the various other species of Acipenser , Scaphirhynchus , Pseudoscaphirhynchus , and Huso to have varying levels of relationship with one another. A potential taxonomy of Acipenseridae is shown here, based on Luo et al . 2019, Nedoluzhko et al . 2020, and Shen et al. 2020. Note the paraphyletic relationships among genera: A. oxyrhinchus [REDACTED] A. sturio [REDACTED] A. dabryanus [REDACTED] A. schrenckii A. transmontanus [REDACTED] H. dauricus A. medirostris [REDACTED] A. mikadoi S. platorhynchus [REDACTED] S. suttkusi [REDACTED] S. albus [REDACTED] P. fedtschenkoi (likely extinct) [REDACTED] P. hermanni P. kaufmanni A. persicus A. stellatus [REDACTED] H. huso [REDACTED] A. ruthenus [REDACTED] A. nudiventris [REDACTED] A. fulvescens [REDACTED] A. brevirostrum [REDACTED] A. baerii A. sinensis A. gueldenstaedtii [REDACTED] The exact placement of Scaphirhynchus varies depending on
9374-505: The naive reader would not assume that they are chronologically related. Each of these four dialects was associated with an independent kingdom on the islands. Of these, Northumbria south of the Tyne , and most of Mercia , were overrun by the Vikings during the 9th century. The portion of Mercia that was successfully defended, and all of Kent , were then integrated into Wessex under Alfred
9483-554: The natural first step is to try and distinguish between environmental influences and those within the animal...In ontogeny the conclusion that a certain change is internally controlled (is 'innate') is reached by elimination . Tinbergen was concerned that the elimination of environmental factors is difficult to establish, and the use of the word innate is often misleading. Development of an organism happens through fertilization, cleavage, blastulation, gastrulation, organogenesis, and metamorphosis into an adult. Each species of animal has
9592-539: The paired fins of ray-finned fish is inside the body wall, although the ray-like structures in the webbing of the fins can be seen externally. Old English Old English ( Englisċ or Ænglisc , pronounced [ˈeŋɡliʃ] ), or Anglo-Saxon , was the earliest recorded form of the English language , spoken in England and southern and eastern Scotland in the early Middle Ages . It developed from
9701-512: The past tense of the weak verbs, as in work and worked . Old English syntax is similar to that of modern English . Some differences are consequences of the greater level of nominal and verbal inflection, allowing freer word order . Old English was first written in runes , using the futhorc —a rune set derived from the Germanic 24-character elder futhark , extended by five more runes used to represent Anglo-Saxon vowel sounds and sometimes by several more additional characters. From around
9810-472: The past to identify over 40 additional species that were rejected by later scientists. Whether the species in the Acipenser and Huso genera are monophyletic (descended from one ancestor) or paraphyletic (descended from many ancestors) is still unclear, though the morphologically motivated division between these two genera clearly is not supported by the genetic evidence. An effort is ongoing to resolve
9919-427: The richest and most significant bodies of literature preserved among the early Germanic peoples. In his supplementary article to the 1935 posthumous edition of Bright's Anglo-Saxon Reader , Dr. James Hulbert writes: Ontogeny Ontogeny (also ontogenesis ) is the origination and development of an organism (both physical and psychological, e.g., moral development ), usually from the time of fertilization of
10028-404: The study and the methods used, with some placing it within the second-most basal clade comprising primarily Pacific species (shown above), whereas others place it in its own clade that is more derived than the secondmost basal clade but less derived than the most derived Atlantic and Central Asian clade. No studies have yet delineated a relationship between it and Pseudoscaphirhynchus . In addition,
10137-480: The successive and progressive origin of new species was based on the same laws as the successive and progressive origin of new embryonic structures. According to Haeckel, development produced novelties, and natural selection would eliminate species that had become outdated or obsolete. Though his view of development and evolution wasn't justifiable, future embryologists tweaked and collaborated with Haeckel's proposals and showed how new morphological structures can occur by
10246-410: The tail end of the spinal cord. Next, the closed neural tube contains neuroepithelial cells that immediately divide after closure and a second type of cell forms; the neuroblast. Neuroblast cells form the mantle layer, which later becomes the gray matter , which then gives rise to a marginal layer that becomes the white matter of the spinal cord. Secondary neurulation is seen in the neural tube of
10355-619: The taxonomic confusion using a continuing synthesis of systematic data and molecular techniques . The phylogeny of Acipenseridae, as in the cladogram , shows that they evolved from the bony fishes . Approximate dates are from Near et al. , 2012. Coelacanths , lungfish [REDACTED] Tetrapods [REDACTED] Polypteriformes ( bichirs , reedfishes ) [REDACTED] Acipenseridae [REDACTED] Polyodontidae [REDACTED] Lepisosteiformes ( gars ) [REDACTED] Amiiformes ( bowfins ) [REDACTED] Teleostei [REDACTED] In currently accepted taxonomy ,
10464-409: The theorized Brittonicisms do not become widespread until the late Middle English and Early Modern English periods, in addition to the fact that similar forms exist in other modern Germanic languages. Old English contained a certain number of loanwords from Latin , which was the scholarly and diplomatic lingua franca of Western Europe. It is sometimes possible to give approximate dates for
10573-564: The time still lacked the letters ⟨j⟩ and ⟨w⟩ , and there was no ⟨v⟩ as distinct from ⟨u⟩ ; moreover native Old English spellings did not use ⟨k⟩ , ⟨q⟩ or ⟨z⟩ . The remaining 20 Latin letters were supplemented by four more: ⟨ æ ⟩ ( æsc , modern ash ) and ⟨ð⟩ ( ðæt , now called eth or edh), which were modified Latin letters, and thorn ⟨þ⟩ and wynn ⟨ƿ⟩ , which are borrowings from
10682-404: The usual ⟨ng⟩ . The addition of ⟨c⟩ to ⟨g⟩ in spellings such as ⟨cynincg⟩ and ⟨cyningc⟩ for ⟨cyning⟩ may have been a means of showing that the word was pronounced with a stop rather than a fricative; spellings with just ⟨nc⟩ such as ⟨cyninc⟩ are also found. To disambiguate,
10791-423: The word was so nearly the same in the two languages that only the endings would put obstacles in the way of mutual understanding. In the mixed population which existed in the Danelaw, these endings must have led to much confusion, tending gradually to become obscured and finally lost. This blending of peoples and languages resulted in "simplifying English grammar". The inventory of Early West Saxon surface phones
10900-449: The zygote undergoes many mitotic divisions , which are also non-sexual cell divisions. Cleavage is the process of cell division, so the starting zygote becomes a collection of identical cells which is a morula and contains cells called blastomeres. Cleavage prepares the zygote to become an embryo, which is from 2 weeks to 8 weeks after conception (fertilization) in humans. After the zygote has become an embryo, it continues dividing into
11009-528: Was also a strong supporter of Darwinism . Haeckel suggested that ontogeny briefly and sometimes incompletely recapitulated or repeated phylogeny in his 1866 book, Generelle Morphologie der Organismen ("General Morphology of Organisms"). Even though his book was widely read, the scientific community was not very convinced or interested in his ideas, so he turned to producing more publications to get more attention. In 1866, Haeckel and others imagined development as producing new structures after earlier additions to
11118-443: Was an allophone of short /ɑ/ which occurred in stressed syllables before nasal consonants (/m/ and /n/). It was variously spelled either ⟨a⟩ or ⟨o⟩. The Anglian dialects also had the mid front rounded vowel /ø(ː)/ , spelled ⟨œ⟩, which had emerged from i-umlaut of /o(ː)/ . In West Saxon and Kentish, it had already merged with /e(ː)/ before the first written prose. Other dialects had different systems of diphthongs. For example,
11227-439: Was based on the West Saxon dialect , away from the main area of Scandinavian influence; the impact of Norse may have been greater in the eastern and northern dialects. Certainly in Middle English texts, which are more often based on eastern dialects, a strong Norse influence becomes apparent. Modern English contains many, often everyday, words that were borrowed from Old Norse, and the grammatical simplification that occurred after
11336-481: Was either /ʃ/ or possibly /ʃː/ when the preceding vowel was short. Doubled consonants are geminated ; the geminate fricatives ⟨ff⟩ , ⟨ss⟩ and ⟨ðð⟩ / ⟨þþ⟩ / ⟨ðþ⟩ / ⟨þð⟩ are always voiceless [ff] , [ss] , [θθ] . The corpus of Old English literature is small but still significant, with some 400 surviving manuscripts. The pagan and Christian streams mingle in Old English, one of
11445-616: Was followed by such writers as the prolific Ælfric of Eynsham ("the Grammarian"). This form of the language is known as the " Winchester standard", or more commonly as Late West Saxon. It is considered to represent the "classical" form of Old English. It retained its position of prestige until the time of the Norman Conquest, after which English ceased for a time to be of importance as a literary language. The history of Old English can be subdivided into: The Old English period
11554-562: Was made between long and short vowels in the originals. (In some older editions an acute accent mark was used for consistency with Old Norse conventions.) Additionally, modern editions often distinguish between velar and palatal ⟨c⟩ and ⟨g⟩ by placing dots above the palatals: ⟨ċ⟩ , ⟨ġ⟩ . The letter wynn ⟨ƿ⟩ is usually replaced with ⟨w⟩ , but ⟨æ⟩ , ⟨ð⟩ and ⟨þ⟩ are normally retained (except when ⟨ð⟩
11663-411: Was spoken and Danish law applied. Old English literacy developed after Christianisation in the late 7th century. The oldest surviving work of Old English literature is Cædmon's Hymn , which was composed between 658 and 680 but not written down until the early 8th century. There is a limited corpus of runic inscriptions from the 5th to 7th centuries, but the oldest coherent runic texts (notably
11772-662: Was subject to strong Old Norse influence due to Scandinavian rule and settlement beginning in the 9th century. Old English is one of the West Germanic languages , and its closest relatives are Old Frisian and Old Saxon . Like other old Germanic languages, it is very different from Modern English and Modern Scots, and largely incomprehensible for Modern English or Modern Scots speakers without study. Within Old English grammar nouns, adjectives, pronouns and verbs have many inflectional endings and forms, and word order
11881-425: Was substantive, pervasive, and of a democratic character. Old Norse and Old English resembled each other closely like cousins, and with some words in common, speakers roughly understood each other; in time the inflections melted away and the analytic pattern emerged. It is most important to recognize that in many words the English and Scandinavian language differed chiefly in their inflectional elements. The body of
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