title: Pasta content: cheese, or vegetables to create ravioli, tortellini, and cannelloni. Fresh egg pasta is well known in the Piedmont region and Emilia Romagna region in North Italy. In this area, dough is only made out of egg yolk and flour resulting in a very refined flavour and texture. This pasta is often served simply with butter sauce and thinly sliced truffles that are native to this region. In other areas, such as Apulia fresh pasta can be made without eggs. The only ingredients needed to make the pasta dough are semolina flour and water, which is often shaped into orecchiette or


title: Pasta content: cavatelli. Fresh pasta for cavatelli is also popular in other places including Sicily. However, the dough is prepared differently: it is made of flour and ricotta cheese instead. Dried pasta can also be defined as factory-made pasta because it is usually produced in large amounts that require large machines with superior processing capabilities to manufacture. Dried pasta is mainly shipped over to farther locations and has a longer shelf life. The ingredients required to make dried pasta include semolina flour and water. Eggs can be added for flavour and richness, but are not needed to make dried pasta. In contrast


title: Pasta content: to fresh pasta, dried pasta needs to be dried at a low temperature for several days to evaporate all the moisture allowing it to be stored for a longer period. Dried pastas are best served in hearty dishes like ragu sauces, soups, and casseroles. Once it is cooked, the dried pasta will usually grow to twice its original size. Therefore, approximately of dried pasta serves up to four people. Pasta is generally served with some type of sauce; the sauce and the type of pasta are usually matched based on consistency and ease of eating. Northern Italian cooking uses less


title: Pasta content: tomato sauce, garlic and herbs. In Northern Italy "white sauce" is more common. However Italian cuisine is best identified by individual regions. Pasta dishes with lighter use of tomato are found in Trentino-Alto Adige and Emilia Romagna. In Bologna, the meat-based "Bolognese sauce" incorporates a small amount of tomato concentrate and a green sauce called "pesto" originates from Genoa. In Central Italy, there are sauces such as "tomato sauce", "amatriciana", "arrabbiata" and the egg-based "carbonara". Tomato sauces are also present in Southern Italian cuisine, where they originated. In Southern Italy more complex variations include pasta paired with fresh vegetables, olives,


title: Pasta content: capers or seafood. Varieties include "puttanesca", "pasta alla norma" (tomatoes, eggplant and fresh or baked cheese), "pasta con le sarde" (fresh sardines, pine nuts, fennel and olive oil), "spaghetti aglio, olio e peperoncino" (literally with garlic, [olive] oil and hot chili peppers). Ingredients to make pasta dough include semolina flour, egg, salt and water. Flour is first mounded on a flat surface and then a well in the pile of flour is created. Egg is then poured into the well and a fork is used to mix the egg and flour. There are a variety of ways to shape the


title: Pasta content: sheets of pasta depending on the type required. The most popular types include penne, spaghetti, and macaroni. Kitchen pasta machines, also called pasta makers, are popular with cooks who make large amounts of fresh pasta. The cook feeds sheets of pasta dough into the machine by hand, and by turning a hand crank, rolls the pasta to thin it incrementally. On the final pass through the pasta machine, the pasta may be directed through a machine 'comb' to shape the pasta noodles as they emerge. Semolina flour consists of a protein matrix with entrapped starch granules. Upon the addition of


title: Pasta content: water, during mixing, intermolecular forces allow the protein to form a more ordered structure in preparation for cooking. Durum wheat is ground into semolina flour which is sorted by optical scanners and cleaned. Pipes allow the flour to move to a mixing machine where it is mixed with warm water by rotating blades. When the mixture is of a lumpy consistency, the mixture is pressed into sheets or extruded. Varieties of pasta such as spaghetti and linguine are cut by rotating blades while pasta such as penne and rotini are extruded. The size and shape of the dies in the


title: Pasta content: extruder through which the pasta is pushed determine the shape that results. The pasta is then dried at a high temperature. The ingredients to make dried pasta usually include water and semolina flour; egg for colour and richness (in some types of pasta), and possibly vegetable juice (such as spinach, beet, tomato, carrot), herbs or spices for colour and flavour. After mixing semolina flour with warm water the dough is kneaded mechanically until it becomes firm and dry. If pasta is to be flavoured, eggs, vegetable juices, and herbs are added at this stage. The dough is then passed into


title: Pasta content: the laminator to be flattened into sheets, then compressed by a vacuum mixer-machine to clear out air bubbles and excess water from the dough until the moisture content is reduced to 12%. Next, the dough is processed in a steamer to kill any bacteria it may contain. The dough is then ready to be shaped into different types of pasta. Depending on the type of pasta to be made, the dough can either be cut or extruded through dies. The pasta is set in a drying tank under specific conditions of heat, moisture, and time depending on the type of


title: Pasta content: pasta. The dried pasta is then packaged: Fresh pasta is sealed in a clear, airtight plastic container with a mixture of carbon dioxide and nitrogen that inhibits microbial growth and prolongs the product's shelf life; dried pastas are sealed in clear plastic or cardboard packages. Gluten, the protein found in grains such as wheat, rye, spelt, and barley, contributes to protein aggregation and firm texture of a normally cooked pasta. Gluten-free pasta is produced with wheat flour substitutes, such as vegetable powders, rice, corn, quinoa, amaranth, oats and buckwheat flours. Other possible gluten-free pasta ingredients may include hydrocolloids to improve


title: Pasta content: cooking pasta with high heat resistance, xanthan gum to retain moisture during storage, or hydrothermally-treated polysaccharide mixtures to produce textures similar to those of normal pasta. The storage of pasta depends its processing and extent of drying. Uncooked pasta is kept dry and can sit in the cupboard for a year if airtight and stored in a cool, dry area. Cooked pasta is stored in the refrigerator for a maximum of five days in an airtight container. Adding a couple teaspoons of oil helps keep the food from sticking to itself and the container. Cooked pasta may be frozen for


title: Pasta content: up to two or three months. Should the pasta be dried completely, it can be placed back in the cupboard. Pasta exhibits a random molecular order rather than a crystalline structure. The moisture content of dried pasta is typically around 12%, indicating that dried pasta will remain a brittle solid until it is cooked and becomes malleable. The cooked product is, as a result, softer, more flexible, and chewy. Semolina flour is the ground endosperm of durum wheat, producing granules that absorb water during heating and an increase in viscosity due to semi-reordering of starch molecules. Another major component of


title: Pasta content: durum wheat is protein which plays a large role in pasta dough rheology. Gluten proteins, which include monomeric gliadins and polymeric glutenin, make up the major protein component of durum wheat (about 75–80%). As more water is added and shear stress is applied, gluten proteins take on an elastic characteristic and begin to form strands and sheets. The gluten matrix that results during forming of the dough becomes irreversibly associated during drying as the moisture content is lowered to form the dried pasta product. Before the mixing process takes place, semolina particles are irregularly shaped and present in different sizes.


title: Pasta content: Semolina particles become hydrated during mixing. The amount of water added to the semolina is determined based on the initial moisture content of the flour and the desired shape of the pasta. The desired moisture content of the dough is around 32% wet basis and will vary depending on the shape of pasta being produced. The forming process involves the dough entering an extruder in which the rotation of a single or double screw system pushes the dough toward a die set to a specific shape. As the starch granules swell slightly in the presence of water and a low


title: Pasta content: amount of thermal energy, they become embedded within the protein matrix and align along the direction of the shear caused by the extrusion process. Starch gelatinization and protein coagulation are the major changes that take place when pasta is cooked in boiling water. Protein and starch competing for water within the pasta cause a constant change in structure as the pasta cooks. In 2011, the three largest producers of dried pasta were Italy (3.2 million tonnes), the United States (3 million tonnes), and Brazil (1.3 million tonnes). By 2016, Italy was still the largest producer of pasta in the world


title: Pasta content: (3.4 million tonnes), followed by United States (2 million tonnes) and 3 countries in the one million tonnes range: Brazil, Turkey, and Russia. The largest per capita consumers of pasta in 2015 were Italy (23.5 kg/person), Tunisia (16.0 kg/person), Venezuela (12.0 kg/person) and Greece (11.2 kg/person). Nationally, the United States is the largest consumer of pasta with 2.7 million tons consumed in 2017. In the European Union, total pasta sales in 2008 were US $8.361 billion, of which $5.722 billion was for dried pasta, $2.244 billion was for fresh or chilled pasta, and $395 million was for canned or preserved


title: Pasta content: pasta. In 2009, retail sales of pasta represented a $2.8 billion market in Italy, $1.4 billion in Germany, and $1.2 billion in France. In 2016, Italy was the world's largest exporter of pasta, with $2.8 billion sold, followed by China with $1.1 billion. The United States was the largest importer of pasta in 2016, with $1 billion acquired, followed by Germany and the UK. When cooked, plain pasta is composed of 62% water, 31% carbohydrates (26% starch), 6% protein, and 1% fat. A 100 gram portion of unenriched cooked pasta provides 160 Calories and a moderate level of manganese (15%


title: Pasta content: of the Daily Value), but few other micronutrients. Pasta has a lower glycemic index than many other staple foods in Western culture, like bread, potatoes, and rice. As pasta was introduced elsewhere in the world, it became incorporated into a number of local cuisines, which often have significantly different ways of preparation from those of Italy. In Hong Kong, the local Chinese have adopted pasta, primarily spaghetti and macaroni, as an ingredient in the Hong Kong-style Western cuisine. When pasta was introduced to several nations, every culture adopted different style of preparing it. In the past, ancient Romans cooked pastas


title: Pasta content: by frying or boiling it. It was also sweetened with honey or tossed with garum. Ancient Romans also enjoyed baking it in rich pies, called timballi. In Cha chaan teng, macaroni is cooked in water and served in broth with ham or frankfurter sausages, peas, black mushrooms, and optionally eggs, reminiscent of noodle soup dishes. This is often a course for breakfast or light lunch fare. These affordable dining shops evolved from American food rations after World War II due to lack of supplies, and they continue to be popular for people with modest means. Two common spaghetti dishes served


title: Pasta content: in Japan are the Bolognese and the Napolitan. In Nepal, macaroni has been adopted and cooked in a Nepalese way. Boiled macaroni is sautéed along with cumin, turmeric, finely chopped green chillies, onions and cabbage. In Greece hilopittes is considered one of the finest types of dried egg pasta. It is cooked either in tomato sauce or with various kinds of casserole meat. It is usually served with Greek cheese of any type. Pasta is also widespread in the Southern Cone, as well most of the rest of Brazil, mostly pervasive in the areas with mild to strong Italian roots,


title: Pasta content: such as Central Argentina, and the eight southernmost Brazilian states (where macaroni are called "macarrão", and more general pasta is under the umbrella term "massa", literally "dough", together with some Japanese noodles, such as "bifum" rice vermicelli and yakisoba, which also entered general taste). The local names for the pasta are many times varieties of the Italian names, such as ñoquis/nhoque for gnocchi, ravioles/ravióli for ravioli, or tallarines/talharim for tagliatelle, although some of the most popular pasta in Brazil, such as the "parafuso" ("screw", "bolt"), a specialty of the country's pasta salads, are also way different both in name and


title: Pasta content: format from its closest Italian relatives, in this case the fusilli. In Sweden, spaghetti is traditionally served with "köttfärssås" (Bolognese sauce), which is minced meat in a thick tomato soup. In the Philippines, spaghetti is often served with a distinct, slightly sweet yet flavourful meat sauce (the base of which would be tomato sauce or paste and ketchup), frequently containing ground beef or pork and diced hot dogs and ham. It is spiced with some soy sauce, heavy quantities of garlic, dried oregano sprigs and sometimes with dried bay leaf, and afterwards topped with grated cheese. Other pasta dishes are


title: Pasta content: also cooked nowadays in the Filipino kitchen, like carbonara, pasta with alfredo sauce, and baked macaroni. These dishes are usually cooked for gatherings and special occasions, like family reunions or Christmas. Macaroni or other tube pasta is also used in "sopas", a local chicken broth soup. "Fettuccine alfredo" with cream, cheese and butter, and spaghetti with tomato sauce (with or without meat) are popular Italian-style dishes in the United States. In Australia, boscaiola sauce, based on bacon and mushrooms, is one favorite among many. Although numerous variations of ingredients for different pasta products are known, in Italy the commercial manufacturing


title: Pasta content: and labeling of pasta for sale as a food product within the country is highly regulated. Italian regulations recognise three categories of commercially manufactured dried pasta as well as manufactured fresh and stabilized pasta: Pasta, or dried pasta with three subcategories – (i.) Durum wheat semolina pasta ("pasta di semola di grano duro"), (ii.) Low grade durum wheat semolina pasta ("pasta di semolato di grano duro") and (iii.) Durum wheat whole meal pasta ("pasta di semola integrale di grano duro"). Pastas made under this category must be made only with durum wheat semolina or durum wheat whole-meal semolina and water,


title: Pasta content: with an allowance for up to 3% of soft-wheat flour as part of the durum flour. Dried pastas made under this category must be labeled according to the subcategory. Special pastas ("paste speciali") – As Pasta above, with additional ingredients other than flour and water or eggs. Special pastas must be labeled as durum wheat semolina pasta on the packaging completed by mentioning the added ingredients used (e.g., spinach). The 3% soft flour limitation still applies. Egg pasta ("pasta all'uovo") – May only be manufactured using durum wheat semolina with at least 4 hens’ eggs (chicken) weighing at least 200


title: Pasta content: grams (without the shells) per kilogram of semolina, or a liquid egg product produced only with hen’s eggs. Pasta made and sold in Italy under this category must be labeled egg pasta. Fresh and stabilized pastas ("paste alimentari fresche e stabilizzate") – Includes fresh and stabilized pastas, which may be made with soft-wheat flour without restriction on the amount. Prepackaged fresh pasta must have a water content not less than 24%, must be stored refrigerated at a temperature of not more than 4 °C (with a 2 °C tolerance), must have undergone a heat treatment at least equivalent to pasteurisation,


title: Pasta content: and must be sold within 5 days of the date of manufacture. Stabilized pasta has a lower allowed water content of 20%, and is manufactured using a process and heat treatment that allows it to be transported and stored at ambient temperatures. The Italian regulations under Presidential Decree N° 187 apply only to the commercial manufacturing of pastas both made and sold within Italy. They are not applicable either to pasta made for export from Italy or to pastas imported into Italy from other countries. They also do not apply to pastas made in restaurants. In the US, regulations for


title: Pasta content: commercial pasta products occur both at the federal and state levels. At the Federal level, consistent with Section 341 of the Federal Food, Drug, and Cosmetic Act, the Food and Drug Administration (FDA) has defined standards of identity for what are broadly termed "macaroni products". These standards appear in 21 CFR Part 139. Those regulations state the requirements for standardized "macaroni products" of 15 specific types of dried pastas, including the ingredients and product-specific labeling for conforming products sold in the US, including imports: Macaroni products – defined as the class of food prepared by drying formed units of dough


title: Pasta content: made from semolina, durum flour, farina, flour, or any combination of those ingredients with water. Within this category various optional ingredients may also be used within specified ranges, including egg white, frozen egg white or dried egg white alone or in any combination; disodium phosphate; onions, celery, garlic or bay leaf, alone or in any combination; salt; gum gluten; and concentrated glyceryl monostearate. Specific dimensions are given for the shapes named macaroni, spaghetti and vermicelli. Noodle products – the class of food that is prepared by drying units of dough made from semolina, durum flour, farina, flour, alone or in


title: Pasta content: any combination with liquid eggs, frozen eggs, dried eggs, egg yolks, frozen yolks, dried yolks, alone or in any combination, with or without water. Optional ingredients that may be added in allowed amounts are onions, celery, garlic, and bay leaf; salt; gum gluten; and concentrated glyceryl monostearate. It is important to note that the federal regulations under 21 CFR Part 139 are standards for the products noted, not mandates. Following the FDA’s standards, a number of states have, at various times, enacted their own statutes that serve as mandates for various forms of macaroni and noodle products that may be


title: Pasta content: produced or sold within their borders. Many of these specifically require that the products sold within those states be of the enriched form. According to a report released by the Connecticut Office of Legislative Research, when Connecticut’s law was adopted in 1972 that mandated certain grain products, including macaroni products, sold within the state to be enriched it joined 38 to 40 other states in adopting the federal standards as mandates. Beyond the FDA’s standards and state statutes, the United States Department of Agriculture (USDA), which regulates federal school nutrition programs, broadly requires grain and bread products served under these


title: Pasta content: programs either be enriched or whole grain (see 7 CFR 210.10 (k) (5)). This includes macaroni and noodle products that are served as part the category grains/breads requirements within those programs. The USDA also allows that enriched macaroni products fortified with protein may be used and counted to meet either a grains/breads or meat/alternative meat requirement, but not as both components within the same meal. Pasta Pasta () is a staple food of traditional Italian cuisine, with the first reference dating to 1154 in Sicily. Also commonly used to refer to the variety of dishes made with it, "pasta" is


title: Penguin content: Penguin Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds. They live almost exclusively in the Southern Hemisphere, with only one species, the Galapagos penguin, found north of the equator. Highly adapted for life in the water, penguins have countershaded dark and white plumage, and their wings have evolved into flippers. Most penguins feed on krill, fish, squid and other forms of sea life which they catch while swimming underwater. They spend roughly half of their lives on land and the other half in the sea. Although almost all penguin species are native to the Southern Hemisphere,


title: Penguin content: they are not found only in cold climates, such as Antarctica. In fact, only a few species of penguin live so far south. Several species are found in the temperate zone, and one species, the Galápagos penguin, lives near the equator. The largest living species is the emperor penguin ("Aptenodytes forsteri"): on average, adults are about tall and weigh . The smallest penguin species is the little blue penguin ("Eudyptula minor"), also known as the fairy penguin, which stands around tall and weighs . Among extant penguins, larger penguins inhabit colder regions, while smaller penguins are generally found in temperate


title: Penguin content: or even tropical climates ("see also" Bergmann's rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human. These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region around 2,000 km south of the equator 35 mya, in a climate decidedly warmer than today. The word "penguin" first appears in the 16th century as a synonym for great auk. When European explorers discovered what are today known as penguins in the Southern Hemisphere, they noticed their similar appearance to


title: Penguin content: the great auk of the Northern Hemisphere, and named them after this bird, although they are not closely related. The etymology of the word "penguin" is still debated. The English word is not apparently of French, Breton or Spanish origin (the latter two are attributed to the French word "pingouin" "auk"), but first appears in English or Dutch. Some dictionaries suggest a derivation from Welsh "pen", "head" and "gwyn", "white", including the Oxford English Dictionary, the American Heritage Dictionary, the Century Dictionary and Merriam-Webster, on the basis that the name was originally applied to the great auk, either because it


title: Penguin content: was found on White Head Island (Welsh "Pen Gwyn") in Newfoundland, or because it had white circles around its eyes (though the head was black). An alternative etymology links the word to Latin "pinguis", which means "fat" or "oil". Support for this etymology can be found in the alternative Germanic word for penguin, "fettgans" or "fat-goose", and the related Dutch word "vetgans". Adult male penguins are called "cocks", females "hens"; a group of penguins on land is a "waddle", and a similar group in the water is a "raft". The number of extant penguin species is debated. Depending on which


title: Penguin content: authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the white-flippered penguin a separate "Eudyptula" species, while others treat it as a subspecies of the little penguin; the actual situation seems to be more complicated. Similarly, it is still unclear whether the royal penguin is merely a color morph of the macaroni penguin. The status of the rockhopper penguins is also unclear. Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka "et al." (2006). Subfamily Spheniscinae – modern penguins Order Sphenisciformes The Early Oligocene genus "Cruschedula" was formerly thought


title: Penguin content: to belong to Spheniscidae, however reexamination of the holotype in 1943 resulted in the genus being placed in Accipitridae. Further examination in 1980 resulted in placement as Aves "incertae sedis". Some recent sources apply the phylogenetic taxon Spheniscidae to what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes, i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian


title: Penguin content: phylogeny is presently resolved, this is confusing, so the established Linnean system is followed here. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography. Although penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005; the evolution of the living genera can be considered resolved by now. The basal penguins lived around the time of the Cretaceous–Paleogene extinction event somewhere in the general area of


title: Penguin content: (southern) New Zealand and Byrd Land, Antarctica. Due to plate tectonics, these areas were at that time less than apart rather than the of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian–Maastrichtian boundary, around 70–68 mya. What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that, by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as


title: Penguin content: flightless birds have generally low resilience to the breakdown of trophic webs that follows the initial phase of mass extinctions because of their below-average dispersal capabilities ("see also" Flightless cormorant). The oldest known fossil penguin species is "Waimanu manneringi", which lived in the early Paleocene epoch of New Zealand, or about 62 mya. While they were not as well-adapted to aquatic life as modern penguins, "Waimanu" were generally loon-like birds but already flightless, with short wings adapted for deep diving. They swam on the surface using mainly their feet, but the wings were – as opposed to most other diving


title: Penguin content: birds (both living and extinct) – already adapting to underwater locomotion. "Perudyptes" from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that, by the Bartonian (Middle Eocene), some 39–38 mya, primitive penguins had spread to South America and were in the process of expanding into Atlantic waters. During the Late Eocene and the Early Oligocene (40–30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's giant penguin was the tallest, growing nearly tall. The New Zealand giant penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also


title: Penguin content: in the Antarctic farther eastwards. Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least two major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other—which is or includes the paleeudyptines as recognized today – occurred on most Antarctic and Subantarctic coasts. But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for


title: Penguin content: example, around 10 known species of penguins ranging in size from medium to huge apparently coexisted some 35 mya during the Priabonian (Late Eocene). It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae – whether they were considered valid, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including "Anthropornis nordenskjoeldi"). The oldest well-described giant penguin, the -tall "Icadyptes salasi", actually occurred as far north as northern Peru about 36 mya.


title: Penguin content: In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Their decline and disappearance coincided with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful. A new lineage, the Paraptenodytes, which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly sized but more gracile Palaeospheniscinae, as well as the radiation that gave rise to the penguin


title: Penguin content: biodiversity of our time. Modern penguins constitute two undisputed clades and another two more basal genera with more ambiguous relationships. The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic. Presumably diverging from other penguins around 40 mya, it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily.


title: Penguin content: Also, the earliest spheniscine lineages are those with the most southern distribution. The genus "Aptenodytes" appears to be the basalmost divergence among living penguins they have bright yellow-orange neck, breast, and bill patches; incubate by placing their eggs on their feet, and when they hatch the chicks are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some Subantarctic islands today. "Pygoscelis" contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the


title: Penguin content: common ancestor of the Spheniscinae, as "Aptenodytes" autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, "Pygoscelis" seems to have diverged during the Bartonian, but the range expansion and radiation that led to the present-day diversity probably did not occur until much later; around the Burdigalian stage of the Early Miocene, roughly 20–15 mya. The genera "Spheniscus" and "Eudyptula" contain species with a mostly Subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head


title: Penguin content: pattern; they are unique among living penguins by nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya. While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4–2 mya. The "Megadyptes"–"Eudyptes" clade occurs at similar latitudes (though not as far north as the Galapagos penguin), has its highest diversity in the New Zealand region, and represents a westward dispersal. They are characterized by hairy yellow ornamental head feathers;


title: Penguin content: their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15–14 mya), but again, the living species of "Eudyptes" are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene. The geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record. The emergence of the Subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages


title: Penguin content: some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the Subantarctic regions rather than in Antarctica itself. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of "Spheniscus" to South America and eventually beyond. Despite this, there is no fossil evidence to support the idea of a crown radiation from the Antarctic continent in the Paleogene, although DNA study favors such a


title: Penguin content: radiation. Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14–12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's Subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts. Penguin ancestry beyond "Waimanu" remains unknown and not well-resolved by molecular or morphological analyses. The latter tend to be confounded by the strong


title: Penguin content: adaptive autapomorphies of the Sphenisciformes; a sometimes perceived fairly close relationship between penguins and grebes is almost certainly an error based on both groups' strong diving adaptations, which are homoplasies. On the other hand, different DNA sequence datasets do not agree in detail with each other either. What seems clear is that penguins belong to a clade of Neoaves (living birds except paleognaths and fowl) that comprises what is sometimes called "higher waterbirds" to distinguish them from the more ancient waterfowl. This group contains such birds as storks, rails, and the seabirds, with the possible exception of the Charadriiformes. Inside


title: Penguin content: this group, penguin relationships are far less clear. Depending on the analysis and dataset, a close relationship to Ciconiiformes or to Procellariiformes has been suggested. Some think the penguin-like plotopterids (usually considered relatives of anhingas and cormorants) may actually be a sister group of the penguins, and that penguins may have ultimately shared a common ancestor with the Pelecaniformes and consequently would have to be included in that order, or that the plotopterids were not as close to other pelecaniforms as generally assumed, which would necessitate splitting the traditional Pelecaniformes in three. A 2014 analysis of whole genomes of 48


title: Penguin content: representative bird species has concluded that penguins are the sister group of Procellariiformes, from which they diverged about 60 million years ago (95% CI, 56.8-62.7). The distantly related puffins, which live in the North Pacific and North Atlantic, developed similar characteristics to survive in the Arctic and sub-Arctic environments. Like the penguins, puffins have a white chest, black back and short stubby wings providing excellent swimming ability in icy water. But, unlike penguins, puffins can fly, as flightless birds would not survive alongside land-based predators such as polar bears and foxes; there are no such predators in the Antarctic. Their


title: Penguin content: similarities indicate that similar environments, although at great distances, can result in similar evolutionary developments, i.e. convergent evolution. Penguins are superbly adapted to aquatic life. Their vestigial wings have become flippers, useless for flight in the air. In the water, however, penguins are astonishingly agile. Penguins' swimming looks very similar to bird's flight in the air. Within the smooth plumage a layer of air is preserved, ensuring buoyancy. The air layer also helps insulate the birds in cold waters. On land, penguins use their tails and wings to maintain balance for their upright stance. All penguins are countershaded for camouflage


title: Penguin content: – that is, they have black backs and wings with white fronts. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above. Diving penguins reach , though there are reports of velocities of (which are more realistic in the case of startled flight). The small penguins do not usually dive deep; they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins can dive deep


title: Penguin content: in case of need. Dives of the large emperor penguin have been recorded reaching a depth of for up to 22 minutes. Penguins either waddle on their feet or slide on their bellies across the snow while using their feet to propel and steer themselves, a movement called "tobogganing", which conserves energy while moving quickly. They also jump with both feet together if they want to move more quickly or cross steep or rocky terrain. Penguins have an average sense of hearing for birds; this is used by parents and chicks to locate one another in crowded colonies. Their eyes


title: Penguin content: are adapted for underwater vision, and are their primary means of locating prey and avoiding predators; in air it has been suggested that they are nearsighted, although research has not supported this hypothesis. Penguins have a thick layer of insulating feathers that keeps them warm in water (heat loss in water is much greater than in air). The emperor penguin has a maximum feather density of about nine feathers per square centimeter which is actually much lower than other birds that live in antarctic environments. However, they have been identified as having at least four different "types" of feather: in


title: Penguin content: addition to the traditional feather, the emperor has afterfeathers, plumules, and filoplumes. The afterfeathers are downy plumes that attach directly to the main feathers and were once believed to account for the bird's ability to conserve heat when under water; the plumules are small down feathers that attach directly to the skin, and are much more dense in penguins than other birds; lastly the filoplumes are small (less than 1 cm long) naked shafts that end in a splay of fibers— filoplumes were believed to give flying birds a sense of where their plumage was and whether or not it


title: Penguin content: needed preening, so their presence in penguins may seem inconsistent, but penguins also preen extensively. The emperor penguin has the largest body mass of all penguins, which further reduces relative surface area and heat loss. They also are able to control blood flow to their extremities, reducing the amount of blood that gets cold, but still keeping the extremities from freezing. In the extreme cold of the Antarctic winter, the females are at sea fishing for food leaving the males to brave the weather by themselves. They often huddle together to keep warm and rotate positions to make sure that


title: Penguin content: each penguin gets a turn in the center of the heat pack. Calculations of the heat loss and retention ability of marine endotherms suggest that most extant penguins are too small to survive in such cold environments. In 2007, Thomas and Fordyce wrote about the "heterothermic loophole" that penguins utilize in order to survive in Antarctica. All extant penguins, even those that live in warmer climates, have a counter-current heat exchanger called the humeral plexus. The flippers of penguins have at least three branches of the axillary artery, which allows cold blood to be heated by blood that has already


title: Penguin content: been warmed and limits heat loss from the flippers. This system allows penguins to efficiently use their body heat and explains why such small animals can survive in the extreme cold. They can drink salt water because their supraorbital gland filters excess salt from the bloodstream. The salt is excreted in a concentrated fluid from the nasal passages. The great auk of the Northern Hemisphere, now extinct, was superficially similar to penguins, and the word "penguin" was originally used for that bird, centuries ago. They are only distantly related to the penguins, but are an example of convergent evolution. Perhaps


title: Penguin content: one in 50,000 penguins (of most species) are born with brown rather than black plumage. These are called isabelline penguins. Isabellinism is different from albinism. Isabelline penguins tend to live shorter lives than normal penguins, as they are not well-camouflaged against the deep, and are often passed over as mates. Although almost all penguin species are native to the Southern Hemisphere, they are not found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. Several species live in the temperate zone; one, the Galápagos penguin, lives as far north


title: Penguin content: as the Galápagos Islands, but this is only made possible by the cold, rich waters of the Antarctic Humboldt Current that flows around these islands. Several authors have suggested that penguins are a good example of Bergmann's Rule where larger bodied populations live at higher latitudes than smaller bodied populations. There is some disagreement about this, and several other authors have noted that there are fossil penguin species that contradict this hypothesis and that ocean currents and upwellings are likely to have had a greater effect on species diversity than latitude alone. Major populations of penguins are found in Angola,


title: Penguin content: Antarctica, Argentina, Australia, Chile, Namibia, New Zealand, and South Africa. Satellite images and photos released in 2018 show the population of two million in France's remote Ile aux Cochons has collapsed, with barely 200,000 remaining, according to a study published in Antarctic Science. Penguins for the most part breed in large colonies, the exceptions being the yellow-eyed and Fiordland species; these colonies may range in size from as few as a 100 pairs for gentoo penguins, to several hundred thousand in the case of king, macaroni and chinstrap penguins. Living in colonies results in a high level of social interaction


title: Penguin content: between birds, which has led to a large repertoire of visual as well as vocal displays in all penguin species. "Agonistic" displays are those intended to confront or drive off, or alternately appease and avoid conflict with, other individuals. Penguins form monogamous pairs for a breeding season, though the rate the same pair recouples varies drastically. Most penguins lay two eggs in a clutch, although the two largest species, the emperor and the king penguins, lay only one. With the exception of the emperor penguin, where the male does it all, all penguins share the incubation duties. These incubation shifts


title: Penguin content: can last days and even weeks as one member of the pair feeds at sea. Penguins generally only lay one brood; the exception is the little penguin, which can raise two or three broods in a season. Penguin eggs are smaller than any other bird species when compared proportionally to the weight of the parent birds; at , the little penguin egg is 4.7% of its mothers' weight, and the emperor penguin egg is 2.3%. The relatively thick shell forms between 10 and 16% of the weight of a penguin egg, presumably to reduce the effects of dehydration and to


title: Penguin content: minimize the risk of breakage in an adverse nesting environment. The yolk, too, is large, and comprises 22–31% of the egg. Some yolk often remains when a chick is born, and is thought to help sustain the chick if the parents are delayed in returning with food. When emperor penguin mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as king and emperor penguins, the chicks assemble in large groups called crèches. Penguins appear to have no


title: Penguin content: special fear of humans, and will approach groups of people without hesitation. This is probably because penguins have no land predators in Antarctica or the nearby offshore islands. Dogs preyed upon penguins while they were allowed in Antarctica during the age of early human exploration as sled dogs, but dogs have long since been banned from Antarctica. Instead, adult penguins are at risk at sea from predators such as sharks, the orca, and the leopard seal. Typically, penguins do not approach closer than around 9 feet (3 meters) at which point they appear to become nervous. This is also the


title: Penguin content: distance that Antarctic tourists are instructed to maintain between themselves and penguins: tourists are instructed not to approach closer than 9 feet, but need not withdraw if the penguins come closer. In June 2011, a penguin came ashore on New Zealand's Peka Peka Beach, 3200 km off course on its journey to Antarctica. Nicknamed Happy Feet, after the movie of the same name, it was suffering from heat exhaustion and had to undergo a number of operations to remove objects like driftwood and sand from its stomach. Happy Feet was a media sensation, with extensive coverage on TV and the


title: Penguin content: web, including a live stream that had thousands of views and a visit from English actor Stephen Fry. Once he had recovered, Happy Feet was released back into the water south of New Zealand. Penguins are popularly loved around the world, primarily for their unusually upright, waddling gait, impressive swimming ability and (compared to other birds) lack of fear of humans. Their striking black-and-white plumage is often likened to a white tie suit. Mistakenly, some artists and writers have penguins based at the North Pole. This is incorrect, as there are no wild penguins in the Arctic. The cartoon series


title: Penguin content: "Chilly Willy" helped perpetuate this myth, as the title penguin would interact with Arctic or subarctic species, such as polar bears and walruses. Penguins have been the subject of many books and films, such as "Happy Feet", "Surf's Up" and "The Penguins of Madagascar", all CGI films; "March of the Penguins", a documentary based on the migration process of the emperor penguin; and a parody titled "Farce of the Penguins". "Mr. Popper's Penguins" is a children's book written by Richard and Florence Atwater; it was named a Newbery Honor Book in 1939. Penguins have also found their way into a


title: Penguin content: number of cartoons and television dramas; perhaps the most notable of these is "Pingu", created by Silvio Mazzola in 1986 and covering more than 100 short episodes. At the end of 2009, "Entertainment Weekly" put it on its end-of-the-decade, "best-of" list, saying, "Whether they were walking ("March of the Penguins"), dancing ("Happy Feet"), or hanging ten ("Surf's Up"), these oddly adorable birds took flight at the box office all decade long." A video game called "Pengo" was released by Sega in 1982. Set in Antarctica, the player controls a penguin character who must navigate mazes of ice-cubes. The player is


title: Penguin content: rewarded with cut-scenes of animated penguins marching, dancing, saluting and playing peekaboo. Several remakes and enhanced editions have followed, most recently in 2012. In 1941, DC Comics introduced the avian-themed character of The Penguin as a supervillain adversary of the superhero Batman ("Detective Comics" #58). He became one of the most enduring enemies in Batman's rogue's gallery. In the 60s "Batman" TV series, as played by Burgess Meredith, he was one of the most popular characters, and in Tim Burton's reimagining of the character in the 1992 film "Batman Returns", he employed an actual army of penguins (mostly African penguins).


title: Penguin content: Several pro, minor, college and high school sport teams have named themselves after the species, with the Pittsburgh Penguins team in the National Hockey League and the Youngstown State Penguins being the most recognizable. The tendency of penguins to form large groups feeds the stereotype that they all look exactly alike, a popular notion exploited by cartoonists such as Gary Larson. Penguins featured regularly in the cartoons of UK cartoonist Steve Bell in his strip in "The Guardian" newspaper, particularly during and following the Falklands War, and the well-known Opus the Penguin, from the cartoons of Berkeley Breathed, is also


title: Penguin content: described as hailing from the Falklands. Opus was a comical, "existentialist" penguin character in the cartoons "Bloom County", "Outland" and "Opus". He was also the star in the Christmas show "A Wish for Wings That Work". In the mid-2000s, penguins became one of the most publicized species of animals that form lasting homosexual couples. A children's book, "And Tango Makes Three", was written about one such penguin family in the New York Zoo. Penguin Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds. They live almost exclusively in the Southern Hemisphere, with only one species, the Galapagos


title: "Diana, Princess of Wales" content: Diana, Princess of Wales Diana, Princess of Wales (born Diana Frances Spencer; 1 July 1961 – 31 August 1997), was a member of the British royal family. She was the first wife of Charles, Prince of Wales, the heir apparent to the British throne, and the mother of Prince William, Duke of Cambridge, and Prince Harry, Duke of Sussex. Diana was born into the Spencer family, a family of British nobility, and she was the youngest daughter of Viscount and Viscountess Althorp. She grew up in Park House, situated on the Sandringham estate, and was educated in England and Switzerland.


title: Plough content: Plough A plough (UK) or plow (US; both ) is a tool or farm implement used in farming for initial cultivation of soil in preparation for sowing seed or planting to loosen or turn the soil. Ploughs were traditionally drawn by working animals such as oxen and horses, but in modern times are mostly drawn by tractors. A plough may be made of wood, iron, or steel frame with an attached blade or stick used to cut the soil and loosen it. It has been a basic instrument for most of recorded history, although despite archeological evidence for its use


title: Plough content: written references to the plough do not appear in the English language before c. 1100, after which point it is referenced frequently. The plough represents one of the major agricultural inventions in human history. The earliest ploughs were wheelless, and the Romans used a wheelless plough called the "aratrum", but Celtic peoples began using wheeled ploughs during the Roman era. The primary purpose of ploughing is to turn over the upper layer of the soil, bringing fresh nutrients to the surface, while burying weeds and the remains of previous crops and allowing them to break down. As the plough is


title: Plough content: drawn through the soil it creates long trenches of fertile soil called furrows. In modern use, a ploughed field is typically left to dry out, and is then harrowed before planting. Ploughing and cultivating a soil homogenises and modifies the upper of the soil to form a plough layer. In many soils, the majority of fine plant feeder roots can be found in the topsoil or plough layer. Ploughs were initially human-powered, but the process became considerably more efficient once animals were pressed into service. The first animal-powered ploughs were undoubtedly pulled by oxen, and later in many areas by


title: Plough content: horses (generally draft horses) and mules, although various other animals have been used for this purpose. In industrialised countries, the first mechanical means of pulling a plough were steam-powered (ploughing engines or steam tractors), but these were gradually superseded by internal-combustion-powered tractors. Modern competitions take place for ploughing enthusiasts like the National Ploughing Championships in Ireland. Use of the plough has decreased in some areas, often those significantly threatened by soil damage and erosion, in favour of shallower ploughing and other less-invasive conservation tillage techniques. In older English, as in other Germanic languages, the plough was traditionally known by other


title: Plough content: names, e.g. Old English "sulh", Old High German "medela", "geiza", "huohilī(n)", Old Norse "arðr" (Swedish "årder"), and Gothic "hōha", all presumably referring to the ard (scratch plough). The term plough, as used today, was not common until 1700. The modern word "plough" comes from Old Norse "plógr", and therefore Germanic, but it appears relatively late (it is not attested in Gothic), and is thought to be a loanword from one of the north Italic languages. Words with the same root appeared with related meanings: in Raetic "plaumorati" "wheeled heavy plough" (Pliny, "Nat. Hist." 18, 172), and in Latin "plaustrum" "farm


title: Plough content: cart", "plōstrum, plōstellum" "cart", and "plōxenum, plōximum" "cart box". The word must have originally referred to the wheeled heavy plough, which was common in Roman northwestern Europe by the 5th century. Orel (2003) tentatively attaches "plough" to a PIE stem *"blōkó-", which gave Armenian "peɫem" "to dig" and Welsh "bwlch" "crack", though the word may not be of Indo-European origin. The diagram ("right") shows the basic parts of the modern plough: Other parts not shown or labelled include the frog (or frame), runner, landside, shin, trashboard, and stilts (handles). On modern ploughs and some older ploughs, the mouldboard is separate


title: Plough content: from the share and runner, so these parts can be replaced without replacing the mouldboard. Abrasion eventually destroys all parts of a plough that come into contact with the soil. When agriculture was first developed, soil was turned using simple hand-held digging sticks and hoes. These were used in highly fertile areas, such as the banks of the Nile where the annual flood rejuvenates the soil, to create drills (furrows) to plant seeds in. Digging sticks, hoes, and mattocks were not invented in any one place, and hoe-cultivation must have been common everywhere agriculture was practiced. Hoe-farming is the traditional


title: Plough content: tillage method in tropical or sub-tropical regions, which are characterised by stony soils, steep slope gradients, predominant root crops, and coarse grains grown at wide distances apart. While hoe-agriculture is best suited to these regions, it is used in some fashion everywhere. Instead of hoeing, some cultures use pigs to trample the soil and grub the earth. Some ancient hoes, like the Egyptian "mr", were pointed and strong enough to clear rocky soil and make seed drills, which is why they are called "hand-ards". However, the domestication of oxen in Mesopotamia and the Indus valley civilization, perhaps as early as


title: Plough content: the 6th millennium BC, provided mankind with the draft power necessary to develop the larger, animal-drawn true "ard" (or scratch plough). The earliest evidence of a ploughed field in the world was found at the Indus Valley Civilization site of Kalibangan (c. 2800 B.C.). Archeological finds in Prague, Czech Republic, push oldest known ploughed field even further, to 3500 - 3800 B.C. Institute of Archeology of CAS report A terracotta model of the early ards was found at Banawali, giving historians insight into the form of the tool. The earliest was the "bow ard", which consists of a "draft-pole" (or


title: Plough content: "beam") pierced by a thinner vertical pointed stick called the "head" (or "body"), with one end being the "stilt" (handle) and the other a "share" (cutting blade) that was dragged through the topsoil to cut a shallow furrow suitable for most cereal crops. The ard does not clear new land well, so hoes or mattocks must be used to pull up grass and undergrowth, and a hand-held, coulter-like "ristle" could be used to cut deeper furrows ahead of the share. Because the ard leaves a strip of undisturbed earth between the furrows, the fields are often cross-ploughed lengthwise and widthwise,


title: Plough content: and this tends to form squarish fields (Celtic fields). The ard is best suited to loamy or sandy soils that are naturally fertilised by annual flooding, as in the Nile Delta and Fertile Crescent, and to a lesser extent any other cereal-growing region with light or thin soil. By the late Iron Age, ards in Europe were commonly fitted with coulters. To grow crops regularly in less-fertile areas, it was once believed that the soil must be turned to bring nutrients to the surface. A major advance for this type of farming was the turnplough, also known as the mouldboard


title: Plough content: plough (UK), moldboard plow (US), or frame-plough. A "coulter" (or "skeith") could be added to cut vertically into the ground just ahead of the "share" (in front of the "frog"), a wedge-shaped cutting edge at the bottom front of the "mouldboard" with the landside of the frame supporting the undershare (below-ground component). The mouldboard plough was introduced in the 18th century and was a major advance in plough technology. The upper parts of the frame carry (from the front) the coupling for the motive power (horses), the coulter and the landside frame. Depending on the size of the implement, and


title: Plough content: the number of furrows it is designed to plough at one time, a forecarriage with a wheel or wheels (known as a furrow wheel and support wheel) may be added to support the frame (wheeled plough). In the case of a single-furrow plough there is only one wheel at the front and handles at the rear for the ploughman to steer and manoeuvre it. When dragged through a field the coulter cuts down into the soil and the share cuts horizontally from the previous furrow to the vertical cut. This releases a rectangular strip of sod that is then lifted


title: Plough content: by the share and carried by the mouldboard up and over, so that the strip of sod (slice of the topsoil) that is being cut lifts and rolls over as the plough moves forward, dropping back to the ground upside down into the furrow and onto the turned soil from the previous run down the field. Each gap in the ground where the soil has been lifted and moved across (usually to the right) is called a "furrow". The sod that has been lifted from it rests at about a 45 degree angle in the next-door furrow and lies up


title: Plough content: the back of the sod from the previous run. In this way, a series of ploughing runs down a field leaves a row of sods that lie partly in the furrows and partly on the ground lifted earlier. Visually, across the rows, there is the land (unploughed part) on the left, a furrow (half the width of the removed strip of soil) and the removed strip almost upside-down lying on about half of the previous strip of inverted soil, and so on across the field. Each layer of soil and the gutter it came from forms the classic furrow. The


title: Plough content: mouldboard plough greatly reduced the amount of time needed to prepare a field, and as a consequence, allowed a farmer to work a larger area of land. In addition, the resulting pattern of low (under the mouldboard) and high (beside it) ridges in the soil forms water channels, allowing the soil to drain. In areas where snow buildup causes difficulties, this lets farmers plant the soil earlier, as the snow runoff drains away more quickly. There are five major parts of a mouldboard plough: Share, landside, mouldboard are bolted to the frog which is an irregular piece of cast iron.


title: Plough content: The base of a plough body is called the frog and the soil wearing parts are bolted to it. The share is the cutting edge of the mouldboard plough. The share makes the horizontal cut that separates the furrow slice from the soil below and when it is worn it is important to fit a new one. Conventional shares have points that are shaped. This shape, which was developed through years of field experience, penetrates ordinary soil efficiently and stands rough use. The share is shaped so that it pulls itself into the ground. As the share wears away, it


title: Plough content: becomes blunt and the plough will require more power to pull it through the soil. A plough body with a worn share will not have enough 'suck' to ensure that it penetrates the ground to its full working depth. The tip of the share is pointed downward, causing the plough to run into the ground. This is called “suction or down suck”; it literally sucks the plough into the ground, to a regulated depth. The clearance, also usually referred to as “suction or down suck”, varies with different makes and types of ploughs (the related clearance at the side is


title: Plough content: called “land suck”). Its configuration is related to soil type, particularly in the down suction, or concavity, of its lower surface. Generally, three degrees of clearance or down suction are recognized: regular for light soil, deep for ordinary dry soil, and double-deep for clay and gravelly soils. In addition, the share has horizontal suction, which is related to the amount its point is bent out of line with the landside. Down suction causes the plough to penetrate to proper depth when pulled forward, while horizontal suction causes the plough to create the desired width of furrow. The share is a


title: Plough content: plane part with trapezoidal shape. It cuts the soil horizontally and lifts it. Common types are regular, winged-plane, bar-point, and share with mounted or welded point. The regular share conserves a good cut but is recommended on stone-free soils. The winged-plane share is used on heavy soil with a moderate amount of stones. The bar-point share can be used in extreme conditions (hard and stony soils). The use of the share with mounted point is somewhere between the last two types. Manufacturers have designed shares of various shapes (trapezium, diamond, etc.) with bolted point and wings, often separately renewable. Sometimes


title: Plough content: the share cutting edge is placed well in advance of the mouldboard to reduce the pulverizing action of the soil. The mouldboard is that part of the plough which receives the furrow slice from the share. The mouldboard is responsible for lifting and turning the furrow slice and sometimes for shattering it, depending on the type of mouldboard, ploughing depth, and soil conditions. The intensity of this action depends on the type of the mouldboard. To suit different soil conditions and crop requirements, mouldboards have been designed in different shapes, each producing its own furrow profile and surface finish, but


title: Plough content: they still basically conform to the original plough body classification. Traditionally, the various types of plough body have been classified as general purpose, digger, and semi-digger, as described below. 1. The general-purpose mouldboard. This is a low draft body with a gently curved and a cross-sectional convex curve from top to bottom, which turns a furrow three parts wide by two parts deep, e.g. 300 mm wide by 200 mm deep. It turns the furrow slice slowly almost without breaking it, and is normally used for shallow ploughing (maximum 200 mm depth). It is useful for grassland ploughing and sets


title: Plough content: up the land for weathering by winter frosts, which reduces the time taken to prepare a seedbed for spring sown crops. 2. The digger mouldboard has a short, abruptly curved with a concave cross-section both from top to bottom and from shin to tail. It turns the furrow slice rapidly, giving maximum shatter and deeper than its width. It is normally used for very deep ploughing (300 mm deep or more). It has a higher power requirement and leaves a very broken surface. Digger ploughs are mainly used for land to be or planted with potatoes and other root crops.


title: Plough content: 3. The semi-digger mouldboard. This is a bit shorter than the general-purpose mouldboard, but with a concave cross-section and a more abrupt curve. Being intermediate between the two mouldboards above described, it has a performance that comes in between (approximately 250 mm deep) and with less shattering than the digger mouldboard. It turns an almost square sectioned furrow and leaves a more broken surface finish. Semi-digger mouldboards can be used at different depths and speeds, making them suitable for most of the general ploughing on the farm. The landside is the flat plate which presses against and transmits the lateral


title: Plough content: thrust of the plough bottom to the furrow wall. It helps to resist the side pressure exerted by the furrow slice on the mouldboard. It also helps in stabilizing the plough while it is in operations. The rear bottom end of the landslide, which rubs against the furrow sole, is known as heel . A heel iron is bolted to the end of the rear of the landside and helps to carry the back of the plough. The landside and share are arranged to give a ‘'lead” towards the unploughed land, thus helping to maintain the correct furrow width. The


title: Plough content: landside is usually made of solid medium carbon steel, and is very short except on the rear bottom of the plough. The heel or rear end of the rear landside may be subject to excessive wear if the rear wheel is out of adjustment, therefore, a chilled iron heel piece is frequently used. This heel is inexpensive and can be easily replaced. The land side is fastened to the frog with the help of plough bolts. The frog (standard) is the central part of the plough bottom to which the other components of the bottom are attached. It is an


title: Plough content: irregular piece of metal, which may be made of cast iron for cast iron ploughs or welded steel for steel ploughs. The frog is the foundation of the plough bottom. It takes the shock resulting from hitting rocks, and therefore should be tough and strong. The frog is in turn fastened to the plough frame. A "runner" extending from behind the share to the rear of the plough controls the direction of the plough, because it is held against the bottom land-side corner of the new furrow being formed. The holding force is the weight of the sod, as it


title: Plough content: is raised and rotated, on the curved surface of the mouldboard. Because of this runner, the mouldboard plough is harder to turn around than the scratch plough, and its introduction brought about a change in the shape of fields – from mostly square fields into longer rectangular "strips" (hence the introduction of the furlong). An advance on the basic design was the "iron ploughshare", a replaceable horizontal cutting surface mounted on the tip of the share. The earliest ploughs with a detachable and replaceable share date from around 1000 BC in the Ancient Near East, and the earliest iron ploughshares


title: Plough content: from ca. 500 BC in China. Early mouldboards were basically wedges that sat inside the cut formed by the coulter, turning over the soil to the side. The ploughshare spread the cut horizontally below the surface, so when the mouldboard lifted it, a wider area of soil was turned over. Mouldboards are known in Britain from the late 6th century on. Mouldboard plough type is usually determined by the method in which the plough is attached to the tractor and by the way it is lifted and carried. The basic types are: 1.Three wheel trailing type – attached to the


title: Plough content: standard tractor drawbar and carried on its own three wheels. 2.Mounted or integral – most use a three-point hitch and have a rear wheel in use only when ploughing. Some also have a gauge wheel to regulate maximum depth. 3.Semi-mounted – used principally for larger ploughs. These have a rear wheel which usually carries weight and side thrust when ploughing and sometimes the weight of the rear end of the plough when lifted. The front end of the plough is carried on the tractor lower or draft links. Gauge wheel – It is an auxiliary wheel of an implement to


title: Plough content: maintain uniform depth of working. Gauge wheel helps to maintain uniformity in respect of depth of ploughing in different soil conditions. It is usually placed in hanging position. Land wheel – It is the wheel of the plough, which runs on the ploughed land. Front furrow wheel – It is the front wheel of the plough, which runs in the furrow. Rear furrow wheel – It is the rear wheel of the plough, which runs in the furrow. When a plough hits a rock or other solid obstruction, serious damage may result unless the plough is equipped with some safety


title: Plough content: device. The damage may be bent or broken shares, bent standards, beams or braces. Three basic types of safety devices are used on mouldboard ploughs as follows: The spring release device was used in the past almost universally on trailing type ploughs with one to three or four bottoms. It is not practical on larger ploughs. When an obstruction is encountered the spring release mechanism in the hitch permits the plough to uncouple from the tractor. When a hydraulic lift is used on the plough, the hydraulic hoses will also usually uncouple automatically when the plough uncouples. Most plough makers


title: Plough content: offer an automatic reset system for tough conditions or rocky soils. The re-set mechanism allows each body to move rearward and upward to pass over obstacle (e.g. rocks hidden below soil surface) without damage. A heavy leaf or coil spring mechanism, which holds the body in its working position under normal conditions, resets the plough after the obstruction is passed. Another type of auto-reset mechanism uses an oil (hydraulic) and gas accumulator. Shock loads cause the oil to compress the gas, when the gas expands again the leg returns to its working ploughing position after passing over the obstacle. The


title: Plough content: most simple mechanism is a breaking (shear) bolt that needs replacement. Shear bolts which break when a plough body hits an obstruction are a cheaper overload protection device. It is important to use the correct replacement bolt. Trip beam ploughs are constructed with a hinge point in the beam. This point is usually located some distance above the top of the plough bottom. The bottom is held in normal ploughing position by a spring operated latch. When an obstruction is encountered the entire bottom is released and hinges back and up so as to pass over the obstruction. It is


title: Plough content: necessary to back up the tractor and plough to reset the bottom This construction is used to protect the individual bottoms. The automatic reset design has only recently been introduced on American ploughs, but has been used extensively on European and Australian ploughs. In this construction the beam is hinged at a point nearly above the point of the share. The bottom is held in the normal position by a set of springs or by a hydraulic cylinder on each bottom. When an obstruction is encountered, the plough bottom hinges back and up in such a way as to pass


title: Plough content: over the obstruction, without stopping the tractor and plough. The bottom automatically returns to normal ploughing position as soon as the obstruction is passed, without any interruption of forward motion. The automatic reset design permits higher field efficiencies since stopping for stones is practically eliminated. It also reduces costs for broken shares, beams and other parts. The fast resetting action also helps produce a better job of ploughing since large areas of unploughed land are not left as when lifting a plough over a stone. Loy ploughing was a form of manual ploughing in Ireland, on very small farms –


title: Plough content: or on very hilly ground, where horses could not work or where farmers could not afford them. It was used up until the 1960s in poorer land. This suited the moist climate of Ireland, as the trenches formed by turning in the sods provided drainage. It also allowed the growing of potatoes in bogs as well as on mountain slopes where no other cultivation could take place. In the basic mouldboard plough the depth of the cut is adjusted by lifting against the runner in the furrow, which limited the weight of the plough to what the ploughman could easily


title: Plough content: lift. This limited the construction to a small amount of wood (although metal edges were possible). These ploughs were fairly fragile, and were not suitable for breaking up the heavier soils of northern Europe. The introduction of wheels to replace the runner allowed the weight of the plough to increase, and in turn allowed the use of a much larger mouldboard faced in metal. These "heavy ploughs" led to greater food production and eventually a significant population increase beginning around 1000 AD. Before the Han Dynasty (202 BC – AD 220), Chinese ploughs were made almost entirely of wood, except


title: Plough content: the iron blade of the ploughshare. By the Han period, the entire ploughshare was made of cast iron; these are the first known heavy mouldboard iron ploughs. The Romans achieved the heavy wheeled mouldboard plough in the late 3rd and 4th century AD, when archaeological evidence appears, inter alia, in Roman Britain. The first indisputable appearance after the Roman period is from 643, in a northern Italian document. Old words connected with the heavy plough and its use appear in Slavic, suggesting possible early use in this region. The general adoption of the carruca heavy plough in Europe appears to


title: Plough content: have accompanied the adoption of the three-field system in the later eighth and early ninth centuries, leading to an improvement of the agricultural productivity per unit of land in northern Europe. This was accompanied by larger fields as well, known variously as carucates, ploughlands, and ploughgates. The basic plough, with coulter, ploughshare and mouldboard, remained in use for a millennium. Major changes in design did not become common until the Age of Enlightenment, when there was rapid progress in design. Joseph Foljambe in Rotherham, England, in 1730 used new shapes as the basis for the Rotherham plough, which also covered


title: Plough content: the mouldboard with iron. Unlike the heavy plough, the Rotherham (or Rotherham swing) plough consisted entirely of the coulter, mouldboard and handles. It was much lighter than conventional designs and became very popular in England. It may have been the first plough to be widely built in factories and the first to be commercially successful. In 1789 Robert Ransome, an iron founder in Ipswich, started casting ploughshares in a disused malting at St Margaret's Ditches. As a result of a mishap in his foundry, a broken mould caused molten metal to come into contact with cold metal, making the metal


title: Plough content: surface extremely hard. This process, chilled casting, resulted in what Ransome advertised as "self-sharpening" ploughs. He received patents for his discovery. James Small further advanced the design. Using mathematical methods he experimented with various designs until he arrived at a shape cast from a single piece of iron, an improvement on the "Scots plough" of James Anderson of Hermiston. A single-piece cast iron plough was also developed and patented by Charles Newbold in the United States. This was again improved on by Jethro Wood, a blacksmith of Scipio, New York, who made a three-part Scots Plough that allowed a broken


title: Plough content: piece to be replaced. In 1837 John Deere introduced the first steel plough; it was so much stronger than iron designs that it could work soil in areas of the US that had previously been considered unsuitable for farming. Improvements on this followed developments in metallurgy: steel coulters and shares with softer iron mouldboards to prevent breakage, the chilled plough (an early example of surface-hardened steel), and eventually mouldboards with faces strong enough to dispense with the coulter. The first mouldboard ploughs could only turn the soil over in one direction (conventionally always to the right), as dictated by the


title: Plough content: shape of the mouldboard, and so the field had to be ploughed in long strips, or "lands". The plough was usually worked clockwise around each land, ploughing the long sides and being dragged across the short sides without ploughing. The length of the strip was limited by the distance oxen (or later horses) could comfortably work without a rest, and their width by the distance the plough could conveniently be dragged. These distances determined the traditional size of the strips: a furlong, (or "furrow's length", ) by a chain () – an area of one acre (about 0.4 hectares); this


title: Plough content: is the origin of the acre. The one-sided action gradually moved soil from the sides to the centre line of the strip. If the strip was in the same place each year, the soil built up into a ridge, creating the ridge and furrow topography still seen in some ancient fields. The turnwrest plough allows ploughing to be done to either side. The mouldboard is removable, turning to the right for one furrow, then being moved to the other side of the plough to turn to the left (the coulter and ploughshare are fixed). In this way adjacent furrows can


title: Plough content: be ploughed in opposite directions, allowing ploughing to proceed continuously along the field and thus avoiding the ridge and furrow topography. The reversible plough (or "rollover plow") has two mouldboard ploughs mounted back-to-back, one turning to the right, the other to the left. While one is working the land, the other is carried upside-down in the air. At the end of each row, the paired ploughs are turned over, so the other can be used. This returns along the next furrow, again working the field in a consistent direction. These ploughs date back to the days of the steam engine


title: Plough content: and the horse. In almost universal use on farms, they have right- and left-handed mouldboards enabling them to work up and down the same furrow. Reversible ploughs may either be mounted or semi-mounted and are heavier and more expensive than right-handed models, but they have the great advantage of leaving a level surface which makes seedbed preparation and harvesting easier. Very little marking out is necessary before ploughing can start and idle running on the headland is minimal compared with conventional ploughs. Driving the tractor with the furrow-side wheels in the furrow bottom provides the most efficient line of draft


title: Plough content: between tractor and plough. It is also easier to steer the tractor and driving with the front wheel against the furrow wall will keep the front furrow at the correct width. This is less satisfactory when using a tractor with very wide front tyres, for although they make better use of the tractor power, the tyres may compact part of the last furrow slice turned on the previous run. The use of furrow widener or a longer mouldboard on the rear body will overcome the problem. The latter moves the soil further towards the ploughed land leaving more room for


title: Plough content: the tractor wheels on the next run. Driving with all four wheels on unploughed land is another solution to the problem of wide tyres. Semi-mounted ploughs can be hitched in a way that allows the tractor to run on unbroken land and pull the plough in correct alignment without any sideways movement (crabbing). Early steel ploughs, like those for thousands of years prior, were "walking ploughs", directed by the ploughman holding onto handles on either side of the plough. The steel ploughs were so much easier to draw through the soil that the constant adjustments of the blade to react


title: Plough content: to roots or clods was no longer necessary, as the plough could easily cut through them. Consequently, it was not long after that the first "riding ploughs" appeared. On these, wheels kept the plough at an adjustable level above the ground, while the ploughman sat on a seat; whereas, with earlier ploughs the ploughman would have had to walk. Direction was now controlled mostly through the draught team, with levers allowing fine adjustments. This led very quickly to riding ploughs with multiple mouldboards, dramatically increasing ploughing performance. A single draught horse can normally pull a single-furrow plough in clean light


title: Plough content: soil, but in heavier soils two horses are needed, one walking on the land and one in the furrow. For ploughs with two or more furrows more than two horses are needed and, usually, one or more horses have to walk on the loose ploughed sod – and that makes hard going for them, and the horse treads the newly ploughed land down. It is usual to rest such horses every half-hour for about ten minutes. Heavy volcanic loam soils, such as are found in New Zealand, require the use of four heavy draught horses to pull a double-furrow plough.


title: Plough content: Where paddocks are more square than long-rectangular it is more economical to have horses four wide in harness than two-by-two ahead, thus one horse is always on the ploughed land (the sod). The limits of strength and endurance of horses made greater than two-furrow ploughs uneconomic to use on one farm. Amish farmers tend to use a team of about seven horses or mules when spring ploughing and as Amish farmers often help each other plough, teams are sometimes changed at noon. Using this method about can be ploughed per day in light soils and about in heavy soils. John


title: Plough content: Deere, an Illinois, US blacksmith, noted that the ploughing of many sticky, non-sandy soils might benefit from modifications in the design of the mouldboard and in the metals used. He noted that a polished needle would enter leather and fabric with greater ease, and a polished pitchfork required less effort as well. In the pursuit of a polished and thus slicker surface for a plough, he experimented with portions of saw blades and by 1837, he was making polished, cast steel ploughs. The energy effort required was lessened, which enabled the use of larger ploughs, making more effective use of


title: Plough content: horse power. The advent of the mobile steam engine allowed steam power to be applied to ploughing from about 1850. In Europe, soil conditions were often too soft to support the weight of heavy traction engines. Instead, counterbalanced, wheeled ploughs, known as "balance ploughs", were drawn by cables across the fields by pairs of ploughing engines on opposite field edges, or by a single engine drawing directly towards it at one end and drawing away from it via a pulley at the other end. The balance plough had two sets of ploughs facing each other, arranged so when one was


title: Plough content: in the ground, the other set was lifted into the air. When pulled in one direction, the trailing ploughs were lowered onto the ground by the tension on the cable. When the plough reached the edge of the field, the other engine pulled the opposite cable, and the plough tilted (balanced), putting the other set of shares into the ground, and the plough worked back across the field. One set of ploughs was right-handed, and the other left-handed, allowing continuous ploughing along the field, as with the turnwrest and reversible ploughs. The man credited with the invention of the ploughing


title: Plough content: engine and the associated balance plough, in the mid nineteenth century, was John Fowler, an English agricultural engineer and inventor. In America the firm soil of the Plains allowed direct pulling with steam tractors, such as the big Case, Reeves or Sawyer-Massey breaking engines. Gang ploughs of up to fourteen bottoms were used. Often these big ploughs were used in regiments of engines, so that in a single field there might be ten steam tractors each drawing a plough. In this way hundreds of acres could be turned over in a day. Only steam engines had the power to draw


title: Plough content: the big units. When internal combustion engines appeared, they had neither the strength nor the ruggedness compared to the big steam tractors. Only by reducing the number of shares could the work be completed. The stump-jump plough was an Australian invention of the 1870s, designed to cope with the breaking up of new farming land, that contains many tree stumps and rocks that would be very expensive to remove. The plough uses a moveable weight to hold the ploughshare in position. When a tree stump or other obstruction such as a rock is encountered, the ploughshare is thrown upwards, clear


title: Plough content: of the obstacle, to avoid breaking the plough's harness or linkage; ploughing can be continued when the weight is returned to the earth after the obstacle is passed. A simpler system, developed later, uses a concave disc (or a pair of them) set at a large angle to the direction of progress, that uses the concave shape to hold the disc into the soil – unless something hard strikes the circumference of the disk, causing it to roll up and over the obstruction. As the arrangement is dragged forward, the sharp edge of the disc cuts the soil, and the


title: Plough content: concave surface of the rotating disc lifts and throws the soil to the side. It doesn't make as good a job as the mouldboard plough (but this is not considered a disadvantage, because it helps fight wind erosion), but it does lift and break up the soil ("see" disc harrow). Modern ploughs are usually multiple reversible ploughs, mounted on a tractor via a three-point linkage. These commonly have between two and as many as seven mouldboards – and "semi-mounted" ploughs (the lifting of which is supplemented by a wheel about halfway along their length) can have as many as eighteen


title: Plough content: mouldboards. The hydraulic system of the tractor is used to lift and reverse the implement, as well as to adjust furrow width and depth. The ploughman still has to set the draughting linkage from the tractor so that the plough is carried at the proper angle in the soil. This angle and depth can be controlled automatically by modern tractors. As a complement to the rear plough a two or three mouldboards-plough can be mounted on the front of the tractor if it is equipped with front three-point linkage. The "chisel plough" is a common tool to get deep tillage


title: Plough content: (prepared land) with limited soil disruption. The main function of this plough is to loosen and aerate the soils while leaving crop residue at the top of the soil. This plough can be used to reduce the effects of compaction and to help break up ploughpan and hardpan. Unlike many other ploughs the chisel will not invert or turn the soil. This characteristic has made it a useful addition to no-till and low-till farming practices that attempt to maximise the erosion-prevention benefits of keeping organic matter and farming residues present on the soil surface through the year. Because of these


title: Plough content: attributes, the use of a chisel plough is considered by some to be more sustainable than other types of plough, such as the mouldboard plough. Chisel ploughs are becoming more popular as a primary tillage tool in row crop farming areas. Basically the chisel plough is a very heavy duty field cultivator intended to operate at depths from 15 cm [6 in] to as much as 46 cm [18 in]. However some models may run much deeper. Each of the individual ploughs, or shanks, are typically set from nine inches (229 mm) to twelve inches (305 mm) apart. Such a


title: Plough content: plough can encounter significant soil drag, consequently a tractor of sufficient power and good traction is required. When planning to plough with a chisel plough it is important to bear in mind that 10 to 20 horsepower (7.5 to 15 kW) per shank will be required, depending on depth. Pull type chisel ploughs are made in working widths from about 2.5 m [8 ft] up to 13.7 m [45 ft], they are tractor mounted and working depth is hydraulically controlled. Those more than about 4 m [13 ft] wide may be equipped with folding wings to reduce transport width. Wider


title: Plough content: machines may have the wings supported by individual wheels and have hinge joints to allow flexing of the machine over uneven ground. The wider models usually have a wheel at each side to control working depth. Three-point hitch mounted units are made in widths from about 1.5 m [5 ft] to 9 m [30 ft]. Cultivators are often similar in form to chisel ploughs, but their goals are different. Cultivator teeth work near the surface, usually for weed control, whereas chisel plough shanks work deep beneath the surface. Consequently, cultivating also takes much less power per shank than does chisel


title: Plough content: ploughing. A ridging plough is used for crops, such as potatoes or scallions, which are grown buried in ridges of soil using a technique called "ridging" or "hilling". A ridging plough has two mouldboards facing away from each other, cutting a deep furrow on each pass, with high ridges either side. The same plough may be used to split the ridges to harvest the crop. This is a variety of ridge plough notable in that the blade points towards the operator. It is used solely by human effort rather than with animal or machine assistance, and is pulled backwards by


title: Plough content: the operator, requiring great physical effort. It is particularly used for second breaking of ground, and for potato planting. It is found in Shetland, some western crofts and more rarely Central Scotland. The tool is typically found on small holdings too small or poor to merit use of animals. The "mole plough" allows underdrainage to be installed without trenches, or it breaks up deep impermeable soil layers that impede drainage. It is a very deep plough, with a torpedo-shaped or wedge-shaped tip, and a narrow blade connecting this to the body. When dragged through the ground, it leaves a channel


title: Plough content: deep under the ground, and this acts as a drain. Modern mole ploughs may also bury a flexible perforated plastic drain pipe as they go, making a more permanent drain – or they may be used to lay pipes for water supply or other purposes. Similar machines, so called pipe-and-cable-laying ploughs, are even used under the sea, for the laying of cables, as well as preparing the earth for side-scan sonar in a process used in oil exploration. Heavy land requires draining to reduce its water content to a level satisfactory for efficient plant growth. Heavy soils usually have a


title: Plough content: system of permanent drains using either perforated plastic or clay pipes which discharge into a ditch. Mole ploughs are used to form small tunnels (mole drains) in the soil at a depth of up to 950 mm (30 in) at an angle to the pipe drains. Water from the mole drains seeps into the pipes and runs along them into a ditch. The mole plough allows underdrainage to be installed without trenches, or it breaks up deep impermeable soil layers which impede drainage. It is a very deep plough, with a torpedo-shaped or wedge-shaped tip, and a narrow blade connecting


title: Plough content: this to the body. When dragged through the ground, it leaves a channel deep under the ground, and this acts as a drain. Modern mole ploughs may also bury a flexible perforated plastic drain pipe as they go, making a more permanent drain – or they may be used to lay pipes for water supply or other purposes. A simple check can be made to find if the subsoil is in the right condition for mole ploughing. Compact a tennis ball sized sample taken at moling depth by hand, then push a pencil through. If the hole remains intact without


title: Plough content: splitting the ball the soil is in an ideal condition for the mole plough. Mole ploughs are usually trailed and pulled by a crawler tractor, but lighter models for use on the three-point linkage of powerful four-wheel drive tractors are also made. A mole plough has a very strong frame which slides along the ground when the machine is in work. A heavy leg, similar to a subsoiler leg, is attached to the frame and a circular section share with a larger diameter expander on a flexible link is bolted to the leg. The bullet shaped share forms a tunnel,


title: Plough content: about 75 mm diameter, in the soil and the expander presses the soil outwards to form a long-lasting drainage channel. The paraplough, or paraplow, is a tool for loosening compacted soil layers 12 to 16 inches deep and still maintain high surface residue levels. The spade plough is designed to cut the soil and turn it on its side, minimising the damage to the earthworms, soil microorganism, and fungi. This helps maximise the sustainability and long term fertility of the soils. Using a bar with square shares mounted perpendicularly and a pivot point to change the bar's angle, the switch


title: Plough content: plough allows ploughing in either direction. It is best in previously-worked soils, as the ploughshares are designed more to turn the soil over than for deep tillage. At the headland, the operator pivots the bar (and thus the ploughshares) to turn the soil to the opposite side of the direction of travel. Switch ploughs are usually lighter than rollover ploughs, requiring less horsepower to operate. Mouldboard ploughing, in cold and temperate climates, no deeper than 20 cm, aerates the soil by loosening it. It incorporates crop residues, solid manures, limestone and commercial fertilisers along with oxygen. By doing so, it


title: Plough content: reduces nitrogen losses by denitrification, accelerates mineralization and increases short-term nitrogen availability for transformation of organic matter into humus. It erases wheel tracks and ruts caused by harvesting equipment. It controls many perennial weeds and pushes back the growth of other weeds until the following spring. It accelerates soil warming and water evaporation in spring because of the lesser quantity of residues on the soil surface. It facilitates seeding with a lighter seeder. It controls many enemies of crops (slugs, crane flies, seedcorn maggots-bean seed flies, borers). It increases the number of "soil-eating" earthworms (endogea) but is detrimental to vertical-dwelling


title: Plough content: earthworms (anecic). Ploughing leaves very little crop residue on the surface, which otherwise could reduce both wind and water erosion. Over-ploughing can lead to the formation of hardpan. Typically farmers break up hardpan up with a subsoiler, which acts as a long, sharp knife to slice through the hardened layer of soil deep below the surface. Soil erosion due to improper land and plough utilisation is possible. Contour ploughing mitigates soil erosion by ploughing across a slope, along elevation lines. Alternatives to ploughing, such as the no till method, have the potential to actually build soil levels and humus. These


title: Plough content: may be suitable to smaller, more intensively cultivated plots, and to farming on poor, shallow or degraded soils that ploughing would further degrade. Plough A plough (UK) or plow (US; both ) is a tool or farm implement used in farming for initial cultivation of soil in preparation for sowing seed or planting to loosen or turn the soil. Ploughs were traditionally drawn by working animals such as oxen and horses, but in modern times are mostly drawn by tractors. A plough may be made of wood, iron, or steel frame with an attached blade or stick used to cut


title: "Peloponnesian War" content: When the rebellious helots were finally forced to surrender and permitted to evacuate the state, the Athenians settled them at the strategic city of Naupaktos on the Gulf of Corinth. In 459 BC, Athens took advantage of a war between its neighbors Megara and Corinth, both Spartan allies, to conclude an alliance with Megara, giving the Athenians a critical foothold on the Isthmus of Corinth. A fifteen-year conflict, commonly known as the First Peloponnesian War, ensued, in which Athens fought intermittently against Sparta, Corinth, Aegina, and a number of other states. For a time during this conflict, Athens controlled not


title: "Pope Clement X" content: rules he pleased. Then the ambassadors of the empire, of France, Spain, and Venice, sent their secretaries to demand an audience of the Pope. The chief chamberlain replied that the Pope was engaged that day. And for four days in succession, the chamberlain gave the same answer to the same applicants. Clement X, learning at length what had occurred, declared that he had given no such order. The ambassadors then sent their secretaries to ask an audience of Cardinal Altieri. He not only refused to admit them, but closed his doors and increased the guard at the pontifical palace, so


title: "Pan flute" content: Pan flute The pan flutes (also known as panpipes or syrinx) are a group of musical instruments based on the principle of the closed tube, consisting of multiple pipes of gradually increasing length (and occasionally girth). Multiple varieties of pan flutes have long been popular as folk instruments. The pipes are typically made from bamboo, giant cane, or local reeds. Other materials include wood, plastic, metal and ivory. The pan flute is named after Pan, the Greek god of nature and shepherds often depicted with such an instrument. In Greek mythology, Syrinx (Σύριγξ) was a forest Nymph. In her attempt


title: "Pan flute" content: to escape the affection of god Pan (a creature half he-goat and half man), she was transformed in to water-reed or calamos (cane-reed). Then, Pan cut several reeds, he placed them in parallel one next to the other, bound them together and made a melodic musical instrument. Ancient Greeks called this instrument Syrinx, in honour of the Muse, and Pandean, or Pan-pipes and Pan-flute, after Pan. The Syrinx, a predominantly pastoral instrument for the Greeks, was adopted by the Etruscans who played it at their festivals and banquets; the Etruscans called it fistula. The Romans adopted the Syrinx from the