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119-472: The subphylum Chelicerata (from Neo-Latin , from French chélicère , from Ancient Greek χηλή ( khēlḗ )  'claw, chela ' and κέρας ( kéras )  'horn') constitutes one of the major subdivisions of the phylum Arthropoda . Chelicerates include the sea spiders , horseshoe crabs , and arachnids (including harvestmen , scorpions , spiders , solifuges , ticks , and mites , among many others), as well as

238-400: A cuticle made of chitin and proteins ; heads that are composed of several segments that fuse during the development of the embryo ; a much reduced coelom ; a hemocoel through which the blood circulates, driven by a tube-like heart. Chelicerates' bodies consist of two tagmata , sets of segments that serve similar functions: the foremost one, called the prosoma or cephalothorax , and

357-408: A wolf spider 's brood cling to rough bristles on the mother's back, and females of some species respond to the "begging" behavior of their young by giving them their prey, provided it is no longer struggling, or even regurgitate food. There are large gaps in the chelicerates' fossil record because, like all arthropods , their exoskeletons are organic and hence their fossils are rare except in

476-453: A broader range of courses relating to urban professions such as law and medicine. All universities required Latin proficiency, obtained in local grammar schools, to obtain admittance as a student. Throughout the period, Latin was the dominant language of university education, where rules were enforced against the use of vernacular languages. Lectures and debates took place in Latin, and writing

595-410: A brood pouch on the belly, where the growing embryos feeds on a nutritive fluid provided by the mother during development, and are therefore matrotrophic . Levels of parental care for the young range from zero to prolonged. Scorpions carry their young on their backs until the first molt , and in a few semi-social species the young remain with their mother. Some spiders care for their young, for example

714-521: A deliberate class barrier for entry to educational institutions. Post-classical Latin, including medieval, Renaissance and Neo-Latin, makes up the vast majority of extant Latin output, estimated as well over 99.99% of the totality. Given the size of output and importance of Latin, the lack of attention to it is surprising to many scholars. The trend is a long one, however, dating back to the late eighteenth and nineteenth centuries, as Neo-Latin texts became looked down on as non-classical. Reasons could include

833-444: A dynamic for purification and ossification of Latin, and thus its decline from a more productive medieval background. Modern Neo-Latin scholars tend to reject this, as for instance word formation and even medieval uses continued; but some see a kernel of truth, in that the standards of Latin were set very high, making it hard to achieve the necessary confidence to use Latin. In any case, other factors are certainly at play, particularly

952-480: A few lagerstätten where conditions were exceptionally suited to preserving fairly soft tissues. The Burgess shale animals like Sidneyia from about 505  million years ago have been classified as chelicerates, the latter because its appendages resemble those of the Xiphosura (horseshoe crabs). However, cladistic analyses that consider wider ranges of characteristics place neither as chelicerates. There

1071-437: A few species of mites keep the eggs inside their bodies until the young emerge. In most chelicerate species the young have to fend for themselves, but in scorpions and some species of spider the females protect and feed their young. The evolutionary origins of chelicerates from the early arthropods have been debated for decades. Although there is considerable agreement about the relationships between most chelicerate sub-groups,

1190-487: A focus of Neo-Latin studies. For instance, stylistic borrowings flowed from Latin to the Dutch vernacular, where models were lacking in the latter. External fertilization In animals, external fertilization typically occurs in water or a moist area to facilitate the movement of sperm to the egg . The release of eggs and sperm into the water is known as spawning . In motile species, spawning females often travel to

1309-454: A high standard. Even in this period, an excessive focus on grammar and poor teaching methods were seen by reformers as a barrier to the acquisition of Latin. Comenius for instance was credited with significant attempts to make Latin more accessible through use of parallel Latin and native language texts, and more interesting through acquisition of vocabulary and the use of modern and more relevant information in texts. Others worried whether it

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1428-687: A kind of bridge of communication across religious as well as linguistic divides in the Res Publica Litterarum . One exception to the general rule of vernacular services in Protestant countries can be observed in the Anglican Church , where with the publication of the Book of Common Prayer of 1559, a Latin edition was published in 1560 for use in universities such as Oxford and the leading grammar and " public schools " (in

1547-443: A larger sperm number and testes size. Smaller testes size and a slower sperm velocity were seen with the anurans that released the sperm into the foam nests instead of into open water. To further increase sperm competition, there is a larger thickness to an anuran oocyte gel, specifically the green tree frog. Anuran sperm also have high longevity and osmotic tolerance compared to fresh water fish. The Caudata order contains all of

1666-452: A lower probability to fertilize. Sessile adult staged animals commonly produce gametes at the same times, also known as a synchronized release of gametes, for external fertilization in the water column. This is helpful because of the lack of mobility these organisms share. They also can rely on turbulent mixing and sperm mobility to enhance the chances of fertilization. The presence of food, resources, favorable environmental conditions, and

1785-418: A number of extinct lineages, such as the eurypterids (sea scorpions) and chasmataspidids . Chelicerata split from Mandibulata by the mid- Cambrian , as evidenced by stem-group chelicerates like Habeliida and Mollisonia present by this time. The surviving marine species include the four species of xiphosurans (horseshoe crabs), and possibly the 1,300 species of pycnogonids (sea spiders), if

1904-462: A pair of pedipalps . Attercopus fimbriunguis , from 386  million years ago in the Devonian period, bears the earliest known silk-producing spigots, and was therefore hailed as a spider, but it lacked spinnerets and hence was not a true spider. Rather, it was likely sister group to the spiders, a clade which has been named Serikodiastida. Close relatives of the group survived through to

2023-476: A purified Classical Latin vocabulary. Recent study tends to identify a style of Latin that was closer to Classical Latin in grammar, sometimes influenced by vernaculars in syntax especially in more everyday writing, but eclectic in choice of vocabulary and generation of new words. Some authors including C. S. Lewis have criticised the Neo-Latin and classicising nature of humanistic Latin teaching for creating

2142-457: A strong role in education and writing in early colonial Mexico, Brazil and in other parts of Catholic Americas. Catholicism also brought Latin to India, China and Japan. Neo-Latin began in Italy with the rise of Renaissance Latin and humanist reform of Latin education, then brought to prominence in northern Europe by writers such as Erasmus , More , and Colet . Medieval Latin had been

2261-527: A suitable location to release their eggs. However, sessile species are less able to move to spawning locations and must release gametes locally. Among vertebrates, external fertilization is most common in amphibians and fish. Invertebrates utilizing external fertilization are mostly benthic, sessile, or both, including animals such as coral, sea anemones , and tube-dwelling polychaetes . Benthic marine plants also reproduce through external fertilization. Environmental factors and timing are key challenges to

2380-509: A synchronized release of gametes in one evening from dusk to midnight. Up to 130 species release gametes during this time. In some cases, fertilization can take place on a spawning animal's surface and when the animals are in the turbulent wake. Although fertilization is usually thought of as a short-term process, there is the possibility of gametes being retained on the surface of an animal for an extended period of time. In order to release an egg or sperm over time, clumps are formed that float in

2499-422: A tail such as frogs and toads. Anurans are commonly used as a model organism for amphibians, because of the large, easy to manipulate eggs, fast developmental rate, high fecundity rate, no parental involvement, and external fertilization. Males will congregate near a lake or pond and establish calling stations. Females approach the area and listen to all of the different male calls, and then continue to move towards

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2618-480: A tube-like heart pumps blood through the hemocoel , which is the major body cavity. Marine chelicerates have gills, while the air-breathing forms generally have both book lungs and tracheae . In general, the ganglia of living chelicerates' central nervous systems fuse into large masses in the cephalothorax, but there are wide variations and this fusion is very limited in the Mesothelae , which are regarded as

2737-473: A wider audience using the same ideas with more practical applications. Over time, the use of Latin continued where international communication with specialist audiences was paramount. Later, where some of the discourse moved to French, English or German, translations into Latin would allow texts to cross language boundaries, while authors in countries with much smaller language populations or less known languages would tend to continue to compose in Latin. Latin

2856-410: Is by various combinations of nephridia and Malpighian tubules . The tubules filter wastes out of the blood and dump them into the hindgut as solids, a system that has evolved independently in insects and several groups of arachnids . Chelicerate nervous systems are based on the standard arthropod model of a pair of nerve cords , each with a ganglion per segment, and a brain formed by fusion of

2975-555: Is considered a basal chelicerate and it has the oldest known chelicerae and proto- book gills . The eurypterids have left few good fossils and one of the earliest confirmed eurypterid, Pentecopterus decorahensis , appears in the Middle Ordovician period 467.3  million years ago , making it the oldest eurypterid. Until recently the earliest known xiphosuran fossil dated from the Late Llandovery stage of

3094-556: Is debate about whether Fuxianhuia from earlier in the Cambrian period, about 525  million years ago , was a chelicerate. Another Cambrian fossil, Kodymirus , was originally classified as an aglaspid but may have been a eurypterid and therefore a chelicerate. If any of these was closely related to chelicerates, there is a gap of at least 43 million years in the record between true chelicerates and their nearest not-quite chelicerate relatives. Sanctacaris , member of

3213-498: Is from a natural to stylised word order. Unlike medieval schools, however, Italian Renaissance methods focused on Classical models of Latin prose style, reviving texts from that period, such as Cicero's De Inventione or Quintilian 's Institutio Oratoria . Teaching of specific, gradually harder Latin authors and texts followed rhetorical practice and learning. In Italy, during the medieval period, at different periods, Classical and Christian authors competed for attention, but

3332-415: Is looking to fertilize the same egg. Sperm chemotaxis is the use of chemical signals to give sperm the ability to navigate an egg and is a huge contributor to reproductive success. Benthic sessile animals that make up the majority of invertebrates using external fertilization rely on ambient water motion to bring the sperm and eggs together. Other invertebrates that externally fertilize are organisms like

3451-565: Is seen as a vital context for understanding the vernacular cultures in the periods when Latin was in widespread productive use. Additionally, Classical reception studies have begun to assess the differing ways that Classical culture was understood in different nations and times. Classicists use the term "Neo-Latin" to describe the Latin that developed in Renaissance Italy as a result of renewed interest in classical civilization in

3570-417: Is very similar to that of scorpions' book lungs. The guts of most modern chelicerates are too narrow to take solid food. All scorpions and almost all spiders are predators that "pre-process" food in preoral cavities formed by the chelicerae and the bases of the pedipalps . However, one predominantly herbivore spider species is known, and many supplement their diets with nectar and pollen . Many of

3689-505: The Acari (ticks and mites) are blood-sucking parasites , but there are many predatory, herbivore and scavenger sub-groups. All the Acari have a retractable feeding assembly that consists of the chelicerae, pedipalps and parts of the exoskeleton , and which forms a preoral cavity for pre-processing food. Harvestmen are among the minority of living chelicerates that can take solid food, and

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3808-635: The Cretaceous Period. Several Carboniferous spiders were members of the Mesothelae , a basal group now represented only by the Liphistiidae , and fossils suggest taxa closely related to the spiders, but which were not true members of the group were also present during this Period. The Late Silurian Proscorpius has been classified as a scorpion, but differed significantly from modern scorpions: it appears wholly aquatic since it had gills rather than book lungs or tracheae ; its mouth

3927-620: The Italian Renaissance of the fourteenth and fifteenth centuries, and then across northern Europe after about 1500, as a key feature of the humanist movement. Through comparison with Latin of the Classical period , scholars from Petrarch onwards promoted a standard of Latin closer to that of the ancient Romans, especially in grammar, style, and spelling. The term Neo-Latin was however coined much later, probably in Germany in

4046-611: The Republic of Letters (Res Publica Litterarum) . Even as Latin receded in importance after 1650, it remained vital for international communication of works, many of which were popularised in Latin translation, rather than as vernacular originals. This in large part explains the continued use of Latin in Scandinavian countries and Russia – places that had never belonged to the Roman Empire – to disseminate knowledge until

4165-556: The Silurian 436 to 428 million years ago , but in 2008 an older specimen described as Lunataspis aurora was reported from about 445  million years ago in the Late Ordovician . The oldest known arachnid is the trigonotarbid Palaeotarbus jerami , from about 420  million years ago in the Silurian period, and had a triangular cephalothorax and segmented abdomen, as well as eight legs and

4284-501: The embryos , suggests that chelicerates are most closely related to myriapods, while hexapods and crustaceans are each other's closest relatives. However, these results are derived from analyzing only living arthropods, and including extinct ones such as trilobites causes a swing back to the "traditional" view, placing trilobites as the sister-group of the Tracheata (hexapods plus myriapods) and chelicerates as least closely related to

4403-433: The opisthosoma – excepting the mites , which have lost any visible division between these sections. The chelicerae , which give the group its name, are the only appendages that appear before the mouth. In most sub-groups, they are modest pincers used to feed. However, spiders' chelicerae form fangs that most species use to inject venom into prey. The group has the open circulatory system typical of arthropods, in which

4522-484: The 14th and 15th centuries. Scientific nomenclatures sometimes prefer the term "New Latin", to show where their terms were coined in the same period. Neo-Latin describes the use of the Latin language for any purpose, scientific or literary, during and after the Renaissance. The beginning of the period cannot be precisely identified. The spread of secular education, the acceptance of humanistic literary norms, and

4641-463: The 1800s among linguists and scientists . Neo-Latin can be said to be the current style of Latin writing, but different periods in its evolution can be seen. Neo-Latin writings were seen as less relevant and deserving of less attention than Classical Latin during the 1800s, as Classical models were asserted as the prime focus for study. Productive use of Latin for most purposes ended in the early 1800s. While Latin remained an actively used language,

4760-544: The Catholic church affirmed their commitment to Latin in the liturgy and as a working language within the hierarchy at the Council of Trent in 1545–63. Jesuit schools were particularly well known for their production of Latin plays , exclusive use of spoken Latin and emphasis on classical written style. However, the standards ultimately achieved by the whole school system were uneven. Not all students would acquire Latin to

4879-631: The German Celtis . In the late 1400s, some schools in the Low Countries were using the new Italian standards of Latin. Erasmus and other pupils promoted the new learning and Latin standards. The Low Countries established itself as a leading centre of humanism and Neo-Latin; Rotterdam and Leuven were especially well known for these intellectual currents. Neo-Latin developed in advance of and in parallel with vernacular languages, but not necessarily in direct competition with them. Frequently

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4998-645: The Neo-Latin period is likewise indeterminate, but Latin as a regular vehicle of communicating ideas became rare following the dissolution of the Holy Roman Empire and after the Congress of Vienna , where French replaced Latin as the language of diplomacy. By 1900, Latin survived primarily in international scientific vocabulary and taxonomy , or more actively, in the upper echelons of the Catholic Church . The term "Neo-Latin" came into use during

5117-612: The Renaissance and Neo-Latin period saw a decisive move back to authors from the Classical period, and away from non-Classical 'minor' authors such as Boethius , whose language was simpler. The changes to schooling in Northern Europe were more profound, as methods had not evolved as quickly. Adopting Italian innovations, changes to the teaching of grammar and rhetoric were promoted by reformers including Calvin , Melanchthon and Luther . Protestants needed Latin to promote and disseminate their ideas, so were heavily involved with

5236-421: The antennae-bearing somite 1, but later investigations reveal that it is retained and corresponds to a pair of chelicerae or chelifores, small appendages that often form pincers . Somite 2 has a pair of pedipalps that in most sub-groups perform sensory functions, while the remaining four cephalothorax segments (somite 4 to 6) have pairs of legs. In basal forms the ocular somite has a pair of compound eyes on

5355-509: The arthropod "family tree" shows chelicerates as less closely related to the other major living groups ( crustaceans ; hexapods , which includes insects ; and myriapods , which includes centipedes and millipedes ) than these other groups are to each other. Recent research since 2001, using both molecular phylogenetics (the application of cladistic analysis to biochemistry , especially to organisms' DNA and RNA ) and detailed examination of how various arthropods' nervous systems develop in

5474-456: The blood as a transport system. The living horseshoe crabs are aquatic and have book gills that lie in a horizontal plane. For a long time it was assumed that the extinct eurypterids had gills, but the fossil evidence was ambiguous. However, a fossil of the 45 millimetres (1.8 in) long eurypterid Onychopterella , from the Late Ordovician period, has what appear to be four pairs of vertically oriented book gills whose internal structure

5593-418: The blood to specific parts of the body, they have open ends rather than joining directly to veins , and chelicerates therefore have open circulatory systems as is typical for arthropods. These depend on individual sub-groups' environments. Modern terrestrial chelicerates generally have both book lungs , which deliver oxygen and remove waste gases via the blood, and tracheae , which do the same without using

5712-465: The body, while scorpions ' are tiny pincers that are used in feeding and project only slightly in front of the head. In basal chelicerates, the pedipalps are unspecialized and subequal to the posterior pairs of walking legs. However, in sea spider and arachnids, the pedipalps are more or less specialized for sensory or prey-catching function – for example scorpions have pincers and male spiders have bulbous tips that act as syringes to inject sperm into

5831-531: The bounds of the Church. Nevertheless, studies and criticism of Biblical translations were a particular and important focus of early Humanism, in Italy and beyond. Prominent Neo-Latin writers who were admired for their style in this early period included Pontano , Petrarch , Salutati , Bruni , Ficino , Pico della Mirandola in Italy; the Spaniard Juan Luis Vives ; and in northern Europe,

5950-431: The brain. The brains of horseshoe crabs include all the ganglia of the prosoma plus those of the first two opisthosomal segments, while the other opisthosomal segments retain separate pairs of ganglia. In most living arachnids , except scorpions if they are true arachnids, all the ganglia, including those that would normally be in the opisthosoma, are fused into a single mass in the prosoma and there are no ganglia in

6069-408: The careful work of Petrarch, Politian and others, first the demand for manuscripts, and then the rush to bring works into print, led to the circulation of inaccurate copies for several centuries following. As the humanist reformers sought both to purify Latin grammar and style, and to make Latin applicable to concerns beyond the ecclesiastical, they began to create a body of Latin literature outside

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6188-411: The compound eye in the other clades has been reduced to a cluster of no more than five pairs of ocelli ), mounted on the sides of the head, plus pigment-cup ocelli ("little eyes"), mounted in the middle. These median ocelli-type eyes in chelicerates are assumed to be homologous with the crustacean nauplius eyes and the insect ocelli. The eyes of horseshoe crabs can detect movement but not form images. At

6307-598: The cultural heritage of Ancient Greece and Byzantium , as well as Greek and Old Church Slavonic languages. Latin was taught extensively in the USA , during the colonial period on the European model of Latin medium education, but was among the first to allow this monopoly to recede. Both Latin and the Classics were very influential nevertheless, and supported an active Latin literature, especially in poetry. Latin played

6426-480: The early nineteenth century. In Neo-Latin's most productive phase, it dominated science, philosophy, law, and theology, and it was important for history, literature, plays, and poetry. Classical styles of writing, including approaches to rhetoric, poetical metres, and theatrical structures, were revived and applied to contemporary subject matter. It was a pan-European language for the dissemination of knowledge and communication between people with different vernaculars in

6545-478: The early nineteenth century. Neo-Latin includes extensive new word formation . Modern scholarly and technical nomenclature , such as in zoological and botanical taxonomy and international scientific vocabulary , draws extensively from this newly minted vocabulary, often in the form of classical or neoclassical compounds . Large parts of this new Latin vocabulary have seeped into English , French and several Germanic languages, particularly through Neo-Latin. In

6664-462: The eggs. If the female does not want to reproduce with the male that jumps onto her back, she will wait until the male leaves or move to a new location. Sperm released into the water must be in close proximity, get to the egg first, and then enter the gel layer of the egg to have the best chance of fertilizing. When the anurans are not close to eggs, they sometimes release their sperm into oocyte containing foam nests, or terrestrial breeders go right to

6783-419: The eighteenth century, Latin was increasingly being learnt as a written and read language, with less emphasis on oral fluency. While it still dominated education, its position alongside Greek was increasingly attacked and began to erode. In the nineteenth century, education in Latin (and Greek) focused increasingly on reading and grammar, and mutated into the 'classics' as a topic, although it often still dominated

6902-482: The extent of potential records, even regarding printed works, there is extensive basic work to be done in cataloguing what is available, as well as in digitisation and translation of important works. Neo-Latin was, at least in its early days, an international language used throughout Catholic and Protestant Europe, as well as in the colonies of the major European powers. This area consisted of most of Europe, including Central Europe and Scandinavia ; its southern border

7021-472: The family Sanctacarididae from the Burgess Shale of Canada , represents the oldest occurrence of a confirmed chelicerate, Middle Cambrian in age. Although its chelicerate nature has been doubted for its pattern of tagmosis (how the segments are grouped, especially in the head), a restudy in 2014 confirmed its phylogenetic position as the oldest chelicerate. Another fossil of the site, Mollisonia ,

7140-401: The females while they lay their eggs to ensure that they fertilize them first. Other times there may be numerous males surrounding a single sac of eggs, creating scramble competition. Cryptobranchid sperm is seen to have higher longevity. This is about 600 times greater than in freshwater fish, but not even close to as high as anurans. Salmon , cod , trout , and char are all examples of

7259-408: The females' reproductive openings when mating. As in all arthropods, the chelicerate body has a very small coelom restricted to small areas round the reproductive and excretory systems. The main body cavity is a hemocoel that runs most of the length of the body and through which blood flows, driven by a tubular heart that collects blood from the rear and pumps it forward. Although arteries direct

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7378-408: The fish that externally fertilize. The females release roe (an egg mass) and the males release milt (seminal fluid containing sperm) into the water, where they diffuse together and fertilize. On top of the sperm locating the oocyte and penetrating the gel layer, it must also infiltrate the mycropyle . If there is turbulent water or even in open, calm water, the closer fish that releases sperm has

7497-598: The food and push it towards the mouth. This is how the earliest arthropods are thought to have fed. Horseshoe crabs convert nitrogenous wastes to ammonia and dump it via their gills, and excrete other wastes as feces via the anus . They also have nephridia ("little kidneys"), which extract other wastes for excretion as urine . Ammonia is so toxic that it must be diluted rapidly with large quantities of water. Most terrestrial chelicerates cannot afford to use so much water and therefore convert nitrogenous wastes to other chemicals, which they excrete as dry matter. Extraction

7616-407: The ganglia just behind the mouth with those ahead of it. If one assume that chelicerates lose the first segment, which bears antennae in other arthropods, chelicerate brains include only one pair of pre-oral ganglia instead of two. However, there is evidence that the first segment is indeed available and bears the cheliceres. There is a notable but variable trend towards fusion of other ganglia into

7735-469: The gel coat of the oocyte to release their sperm. Over the course of a breeding season, males can copulate numerous times by releasing sperm anywhere he finds unfertilized eggs or encounters a female who is/wants to spawn. Females, however, can only release eggs once per breeding season. Releasing sperm directly into the water increases sperm competition through agonistic behavior and spawning in groups. This has been tested, with good evidence associated with

7854-431: The group includes predators, herbivores and scavengers. Horseshoe crabs are also capable of processing solid food, and use a distinctive feeding system. Claws at the tips of their legs grab small invertebrates and pass them to a food groove that runs from between the rearmost legs to the mouth, which is on the underside of the head and faces slightly backwards. The bases of the legs form toothed gnathobases that both grind

7973-677: The guts of most modern chelicerates are too narrow for this, and they generally liquidize their food by grinding it with their chelicerae and pedipalps and flooding it with digestive enzymes . To conserve water, air-breathing chelicerates excrete waste as solids that are removed from their blood by Malpighian tubules , structures that also evolved independently in insects . While the marine horseshoe crabs rely on external fertilization , air-breathing chelicerates use internal but usually indirect fertilization. Many species use elaborate courtship rituals to attract mates. Most lay eggs that hatch as what look like miniature adults, but all scorpions and

8092-764: The higher chance of fertilizing the eggs. If sperm is released too early, it can become too dilute or die before it ever reaches the eggs. If sperm is released too late, there is a higher chance that a different fish's sperm has already reached the eggs. Also, the faster and more numerous the sperm, the better. There are instances where males will create habitats in an attempt to monopolize females and increase their chance of fertilizing eggs. Fishes can be iteroparous , and spawn more than once, but there are some who only spawn once before death, known as semelparous . Within iteroparous fish, they usually give no parental care with external fertilization. The sperm present in male fish are immotile while in testes and in seminal fluid, and

8211-708: The inclusion of the Pycnogonida in this taxon has been questioned, and the exact position of scorpions is still controversial, though they were long considered the most basal of the arachnids. Venom has evolved three times in the chelicerates; spiders, scorpions and pseudoscorpions, or four times if the hematophagous secretions produced by ticks are included. In addition there have been undocumented descriptions of venom glands in Solifugae. Chemical defense has been found in whip scorpions , shorttailed whipscorpions , harvestmen , beetle mites and sea spiders . Although

8330-485: The lack of predators are thought of when thinking of survival of the next generation. When the female is producing eggs, they perform predator satiation, which is when multiple females will release gametes in a mass reproductive event. The Great Barrier Reef is known for having a “mass spawn.” This occurs the week after the full moon in October. This mass reproductive event is given by reef forming corals, which perform

8449-461: The late eighteenth century, as Neulatein , spreading to French and other languages in the nineteenth century. Medieval Latin had diverged quite substantially from the classical standard and saw notable regional variation and influence from vernacular languages. Neo-Latin attempts to return to the ideal of Golden Latinity in line with the Humanist slogan ad fontes . The new style of Latin

8568-409: The latter are indeed chelicerates. On the other hand, there are over 77,000 well-identified species of air-breathing chelicerates, and there may be about 500,000 unidentified species. Like all arthropods , chelicerates have segmented bodies with jointed limbs, all covered in a cuticle made of chitin and proteins . The chelicerate body plan consists of two tagmata , the prosoma and

8687-641: The learner with spoken vocabulary for common topics, such as play and games, home work and describing travel. In short, Latin was taught as a "completely normal language", to be used as any other. Colloquia would also contain moral education. At a higher level, Erasmus' Colloquia helped equip Latin speakers with urbane and polite phraseology, and means of discussing more philosophical topics. Changes to Latin teaching varied by region. In Italy, with more urbanised schools and Universities, and wider curricula aimed at professions rather than just theology, Latin teaching evolved more gradually, and earlier, in order to speed up

8806-423: The learning of Latin. For instance, initial learning of grammar in a basic Latin word order followed the practice of medieval schools. In both medieval and Renaissance schools, practice in Latin written skills would then extend to prose style composition, as part of 'rhetoric'. In Italy, for prose for instance, a pupil would typically be asked to convert a passage in ordo naturalis to ordo artificialis , that

8925-478: The level of abstract thought addressed to other specialists. To begin with, knowledge was already transmitted through Latin and it maintained specialised vocabularies not found in vernacular languages. This did not preclude scientific writings also existing in vernaculars; for example Galileo , some of whose scientific writings were in Latin, while others were in Italian, the latter less academic and intended to reach

9044-586: The liturgy, resisting attempts even in the New World and China to diverge from it. As noted above, Jesuit schools fuelled a high standard of Latinity, and this was also supported by the growth of seminaries, as part of the Counter Reformation 's attempts to revitalise Catholic institutions. While in Protestant areas Latin was pushed out of the Church, this did not make Protestants hostile to Latin in education or universities. In fact, Latin remained

9163-423: The main choice is the location of where to lay her eggs. A female can choose a nest close to the male she wants to fertilize her eggs, but there is no guarantee that the preferred male will fertilize any of the eggs. Broadcast spawners have a very weak selection , due to the randomness of releasing gametes . To look into the effect of female choice on external fertilization, an in vitro sperm competition experiment

9282-609: The male deposit his spermatophore (package of sperm) on the ground, which is then picked up by the female. Or the male store his sperm in appendages modified into sperm transfer organs, such as the pedipalps in male spiders, which is inserted into the female genital openings during copulation. Courtship rituals are common, especially in species where the male risk being eaten before mating. Most arachnids lay eggs, but all scorpions and some mites are viviparous , giving birth to live young (even more mites are ovoviviparous, but most are oviparous). Female pseudoscorpions carry their eggs in

9401-421: The mate she chooses. This is the anuran's sexual selection . It has been concluded that females prefer a male with a more attractive call, which is also the larger male. Copulation occurs when a male anuran hops onto the back of a female. They then move to a spot near water to simultaneously release their sperm and eggs. Other males in the area can also release sperm onto the eggs to also attempt to fertilize

9520-605: The most well known example. Throughout this period, Latin was a universal school subject, and indeed, the pre-eminent subject for elementary education in most of Europe and other places of the world that shared its culture. Schools were variously known as grammar schools in Britain, Latin schools in France, Germany, the Netherlands and colonial North America, and also Gymnasia in Germany and many other countries. Latin

9639-537: The mouth, while pedipalps are tritocerebral and arise from somite 2, behind the mouth. The chelicerae ("claw horns") that give the sub-phylum its name normally consist of three sections, and the claw is formed by the third section and a rigid extension of the second. However, spiders' have only two sections, and the second forms a fang that folds away behind the first when not in use. The relative sizes of chelicerae vary widely: those of some fossil eurypterids and modern harvestmen form large claws that extended ahead of

9758-439: The nervous system. In fact, spiders and other arthropods have modified their cuticles into elaborate arrays of sensors. Various touch and vibration sensors, mostly bristles called setae , respond to different levels of force, from strong contact to very weak air currents. Chemical sensors provide equivalents of taste and smell , often by means of setae. Living chelicerates have both compound eyes (only in horseshoe crabs , as

9877-415: The old one and wait for the new one to harden. Until the new cuticle hardens the animals are defenseless and almost immobilized. Chelicerae and pedipalps are the two pairs of appendages closest to the mouth; they vary widely in form and function and the consistent difference between them is their position in the embryo and corresponding neurons: chelicerae are deutocerebral and arise from somite 1, ahead of

9996-504: The oldest and most basal group of spiders. Most chelicerates rely on modified bristles for touch and for information about vibrations, air currents, and chemical changes in their environment. The most active hunting spiders also have very acute eyesight. Chelicerates were originally predators, but the group has diversified to use all the major feeding strategies: predation, parasitism , herbivory , scavenging and eating decaying organic matter . Although harvestmen can digest solid food,

10115-475: The opisthosoma. However, in the Mesothelae , which are regarded as the most basal living spiders, the ganglia of the opisthosoma and the rear part of the prosoma remain unfused, and in scorpions the ganglia of the cephalothorax are fused but the abdomen retains separate pairs of ganglia. As with other arthropods, chelicerates' cuticles would block out information about the outside world, except that they are penetrated by many sensors or connections from sensors to

10234-400: The other extreme, jumping spiders have a very wide field of vision, and their main eyes are ten times as acute as those of dragonflies , able to see in both colors and UV-light. Horseshoe crabs use external fertilization ; the sperm and ova meet outside the parents' bodies. Despite being aquatic, they spawn on land in the intertidal zone on the beach. The female digs a depression in

10353-474: The other groups. Xiphosura (horseshoe crabs) [REDACTED] Eurypterida † [REDACTED] Chasmataspidida † [REDACTED] Scorpiones [REDACTED] Opiliones (harvestmen) [REDACTED] Neo-Latin Neo-Latin (sometimes called New Latin or Modern Latin ) is the style of written Latin used in original literary, scholarly, and scientific works, first in Italy during

10472-512: The period, English schools established with charitable structures open to the general public; now a kind of private academy), where the liturgy was still permitted to be conducted in Latin. In this period, it was common for poets and authors to write in Latin, either in place of or in addition to their native language. Latin was a language for "high art" in an "eternal language", that authors supposed might outlast contemporary vernacular writings. It allowed for an international readership that shared

10591-472: The practical working language of the Roman Catholic Church , and was taught throughout Europe to clerics through the medieval university system. It was a flexible language, with many neologisms. Changes in grammatical practices regarding syntax and other elements such as conjunctions had become established. The Renaissance reinforced the position of Latin as a spoken and written language by

10710-471: The process of emulating Classical models did not become complete. For instance, Catholic traditions preserved some features of medieval Latin, given the continued influence of some aspects of medieval theology. In secular texts, such as scientific, legal and philosophical works, neologisms continued to be needed, so while Neo-Latin authors might choose new formulations, they might also continue to use customary medieval forms, but in either case, could not aim for

10829-440: The rear tagma is called the opisthosoma or abdomen . However, in the Acari (mites and ticks) there is no visible division between these sections. The prosoma is formed in the embryo by fusion of the ocular somite (referred as "acron" in previous literatures), which carries the eyes and labrum , with six post-ocular segments (somite 1 to 6), which all have paired appendages. It was previously thought that chelicerates had lost

10948-434: The reform of Latin teaching. Among the most influential of these reformers was Calvin's Latin teacher and educational collaborator Corderius , whose bilingual colloquies were aimed at helping French-speaking children learn to speak Latin. Among Latin schools, the rapid growth of Jesuit schools made them known for their dedication to high attainment in written and spoken Latin to educate future priests. This took place after

11067-768: The reform of the new secular Latin teaching. The heyday of Neo-Latin was 1500–1700, when in the continuation of the Medieval Latin tradition, it served as the lingua franca of science, medicine, legal discourse, theology, education, and to some degree diplomacy in Europe. This coincided with the growth of printed literature; Latin dominated early publishing. Classic works such as Thomas More 's Utopia were published. Other prominent writers of this period include Dutchmen Grotius and Secundus and Scotsman George Buchanan . Women, while rarely published, also wrote and composed poetry in Latin, Elizabeth Jane Weston being

11186-401: The remaining appendages form spinnerets that extrude silk , while those of horseshoe crabs (Xiphosura) form gills . Like all arthropods, chelicerates' bodies and appendages are covered with a tough cuticle made mainly of chitin and chemically hardened proteins. Since this cannot stretch, the animals must molt to grow. In other words, they grow new but still soft cuticles, then cast off

11305-598: The rising belief during this period in the superiority of vernacular literatures, and the idea that only writing in one's first language could produce genuinely creative output, found in nationalism and Romanticism. More recently, the lack of trained Latinists has added to the barriers. More academic attention has been given to Neo-Latin studies since 1970, and the role and influence of Latin output in this period has begun to be reassessed. Rather than being an adjunct to Classical Latin forms, or an isolated, derivative and now largely irrelevant cultural output, Neo-Latin literature

11424-496: The salamanders and newts, amphibians that have tails. Within this, the only subgroups that externally fertilize are Cryptobranchidae (giant salamanders) Sirenidae , and Hynobiidae . The females release egg sacs onto stones or branches and the male later hovers over the eggs to release the sperm to them. Males are seen to be very protective over the eggs and may continue to hover over the eggs after sperm release to decrease sperm competition. In some cases, males may even latch onto

11543-503: The same Classical and recent Latin cultural reference points. The literature did not stand apart from vernaculars, as naturally allusions and the same reference points could flow across language boundaries. However, these dynamics have become less well understood, as academics and other readers are not as familiar with the Latin works of the period, sometimes resulting in simplistic notions of competition and replacement of Latin over time. The actual processes were more complicated and are now

11662-435: The same people were codifying and promoting both Latin and vernacular languages, in a wider post-medieval process of linguistic standardisation. However, Latin was the first language that was available, fully formed, widely taught and used internationally across a wide variety of subjects. As such, it can be seen as the first "modern European language". It should also be noted that for Italian reformers of written Latin, there

11781-716: The scholarship by the Renaissance Humanists . Although scholarship initially focused on Ancient Greek texts, Petrarch and others began to change their understanding of good style and their own usage of Latin as they explored the texts of the Classical Latin world. Skills of textual criticism evolved to create much more accurate versions of extant texts through the fifteenth and sixteenth centuries, and some important texts were rediscovered. Comprehensive versions of author's works were published by Isaac Casaubon , Joseph Scaliger and others. Nevertheless, despite

11900-478: The school curriculum, especially for students aiming for entry to university. Learning moved gradually away from poetry composition and other written skills; as a language, its use was increasingly passive outside of classical commentaries and other specialised texts. Latin remained in active use in eastern Europe and Scandinavia for a longer period. In Poland, it was used as a vehicle of local government. This extended to those parts of Poland absorbed by Germany. Latin

12019-410: The sea urchin, are confined to shallow burrows on exposed shores. Turbulent flows in the surf zone also create a transport of gametes. Hydrodynamic conditions and gamete properties control the efficiency of fertilization because they influence the rate at which the water mixes. The only dilemma with turbulence is the possibility of dilution of sperm and egg because of over mixing. Rapid mixing can cause

12138-453: The sides and four pigment-cup ocelli ("little eyes") in the middle. The mouth is between somite 1 and 2 (chelicerae and pedipalps). The opisthosoma consists of thirteen or fewer segments, may or may not end with a telson . In some taxa such as scorpion and eurypterid the opisthosoma divided into two groups, mesosoma and metasoma . The abdominal appendages of modern chelicerates are missing or heavily modified – for example in spiders

12257-466: The success of external fertilization. While in the water, the male and female must both release gametes at similar times in order to fertilize the egg. Gametes spawned into the water may also be washed away, eaten, or damaged by external factors. Sexual selection may not seem to occur during external fertilization, but there are ways it actually can. The two types of external fertilizers are nest builders and broadcast spawners. For female nest builders,

12376-574: The venom of a few spider and scorpion species can be very dangerous to humans, medical researchers are investigating the use of these venoms for the treatment of disorders ranging from cancer to erectile dysfunction . The medical industry also uses the blood of horseshoe crabs as a test for the presence of contaminant bacteria . Mites can cause allergies in humans, transmit several diseases to humans and their livestock , and are serious agricultural pests . The Chelicerata are arthropods as they have: segmented bodies with jointed limbs, all covered in

12495-465: The water column. This allows for a variation in locations and time differences of fertilization taking place by the same invertebrate. The earliest amphibians were all internal fertilizers. It was not until 300 million years ago that the Anura (early internal fertilizer) and Caudata (early external fertilizer) orders had begun. Most anurans now externally fertilize. Anurans are the amphibians lacking

12614-417: The water where fertilization occurs. The male then collects the eggs and carries them around under his body. Being air-breathing animals, although many mites have become secondary aquatic, the arachnids use internal fertilization . Except for opiliones and some mites, where the male have a penis used for direct fertilization, fertilization in arachnids is indirect. Indirect fertilization happens in two ways;

12733-428: The wet sand, where she will release her eggs. The male, usually more than one, then releases his sperm onto them. Their trilobite -like larvae look rather like miniature adults as they have full sets of appendages and eyes, but initially they have only two pairs of book-gills and gain three more pairs as they molt . Also the sea spiders have external fertilization. The male and female release their sperm and eggs into

12852-413: The wide availability of Latin texts following the invention of printing , mark the transition to a new era of scholarship at the end of the 15th century, but there was no simple, decisive break with medieval traditions. Rather, there was a process of change in education, a choice of literary and stylistic models, and a move away from medieval techniques of language formation and argumentation. The end of

12971-417: The widening of education and its needs to address many more practical areas of knowledge, many of which were being written about for national audiences in the vernacular. The exact size of the Neo-Latin corpus is currently incalculable, but dwarfs that of Latin in all other periods combined. Material includes personal, unpublished, bureaucratic, educational, and academic output such as notes and theses. Given

13090-443: Was adopted throughout Europe, first through the spread of urban education in Italy, and then the rise of the printing press and of early modern schooling. Latin was learnt as a spoken language as well as written, as the vehicle of schooling and University education, while vernacular languages were still infrequently used in such settings. As such, Latin dominated early publishing, and made up a significant portion of printed works until

13209-453: Was appropriate to put so much emphasis on abstract language skills such as Latin poetry composition. As time went on, the difficulties with Latin teaching began to lead to calls to move away from an emphasis on spoken Latin and the introduction of more native-language-medium teaching. At the beginning of the Renaissance, universities in northern Europe were still dominated by theology and related topics, while Italian universities were teaching

13328-682: Was completely under its head and almost between the first pair of legs, as in the extinct eurypterids and living horseshoe crabs . Fossils of terrestrial scorpions with book lungs have been found in Early Devonian rocks from about 402  million years ago . The oldest species of scorpion found as of 2021 is Dolichophonus loudonensis , which lived during the Silurian, in present-day Scotland. Hexapoda Crustacea Myriapoda Chelicerata Chelicerata Crustacea Trilobita Hexapoda Myriapoda The "traditional" view of

13447-412: Was frequently the normal medium of education, both for teaching the Latin language, and for other subjects. Fluency in spoken Latin was an objective as well as the ability to read and write; evidence of this includes the emphasis on use of diacritics to maintain understanding of vowel quantity, which is important orally, and also on the use of Colloquia for children's learning, which would help to equip

13566-446: Was in Latin, across the curriculum. Many universities hosted newly or recently-written Latin plays , which formed a significant body of literature before 1650. Plays included satires on student life, such as the play Studentes (Students), which went through many reprints. Enforcement of Latin-only rules tended to decline especially after 1650. Latin dominated topics of international academic and scientific interest, especially at

13685-423: Was no clear divide between Italian and Latin; the latter was seen by Petrarch for example as an artificial and literary version of the spoken language. While Italian in this period also begins to be used as a separate written language, it was not always seen as wholly separate from Latin. The Protestant Reformation (1520–1580), though it removed Latin from the liturgies of the churches of Northern Europe, promoted

13804-647: Was of course the major language of Christian theology. Both Catholic and Protestant writers published in Latin. While Protestant writers would also write in vernaculars, Latin was important for the international dissemination of ideas. Legal discourse, medicine, philosophy and sciences started from a strong Latin tradition, and continued as such. This began to change in the late seventeenth century, as philosophers and others began to write in their native language first, and translate into Latin for international audiences. Translations would tend to prioritise accuracy over style. The Catholic Church made exclusive use of Latin in

13923-421: Was performed. The results concluded that there was a decreased importance of sperm number, but increased the importance of the sperm velocity, thus changing the outcome of sperm competition. The ovarian fluid also increased the paternity for the preferred male because they release fewer and faster sperm. The success of a male fertilizing an egg relies on the ability of a male's sperm to outcompete other sperm that

14042-675: Was the Mediterranean Sea, with the division more or less corresponding to the modern eastern borders of Finland , the Baltic states , Poland , Slovakia , Hungary and Croatia . Russia 's acquisition of Kyiv in the later 17th century introduced the study of Latin to Russia. Russia relied on Latin for some time as a vehicle to exchange scientific knowledge. Nevertheless, the use of Latin in Orthodox eastern Europe did not reach pervasive levels due to their strong cultural links to

14161-615: Was used as a common tongue between parts of the Austrian Empire, particularly Hungary and Croatia, at least until the 1820s. Croatia maintained a Latin poetry tradition through the nineteenth century. Latin also remained the language of the Catholic Church and of oral debate at a high level in international conferences until the mid twentieth century. Over time, and especially in its later phases after its practical value had severely declined, education that included strong emphasis on Latin and Greek became associated with elitism and as

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