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Normandie-class battleship. to . The ships would have had a crew of 44 officers and 1,160 enlisted men when serving as a flagship. Section:Description.:Armament. The main battery of the "Normandie" class consisted of a dozen 45-caliber Canon de 34 cm Modèle 1912s mounted in three quadruple turrets. One turret was placed forward, one amidships, and one aft, all on the centerline. The turrets weighed , and were electrically trained and hydraulically elevated. The guns were divided into pairs and moved together in twin cradles; a thick bulkhead divided the turrets in half. Each pair of guns had its own ammunition hoist and
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Normandie-class battleship. magazine. They could be fired simultaneously or independently. The guns had a range of and had a rate of fire of two rounds per minute. The shells were armor-piercing rounds and were fired with a muzzle velocity of . Each gun was to have been supplied with 100 rounds of ammunition. Five rangefinders provided fire-control for the main battery. Two of the rangefinders were mounted on the conning tower and the other three were placed atop each of the turrets. The turrets also had auxiliary gunnery-control stations. The ships would also have been armed with a secondary battery of twenty-four
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Normandie-class battleship. 55-caliber 138.6 mm Modèle 1910 guns, each singly mounted in casemates near the main-gun turrets. These guns fired a shell at a muzzle velocity of . The guns would have been supplied with 275 rounds of ammunition each. Six Canon de Modèle 1902 anti-aircraft guns, which were converted from low-angle guns, would also have been carried by the ships. The ships also would have been equipped with six underwater torpedo tubes, three on each broadside. Each ship was to be supplied with 36 torpedoes. Section:Description.:Protection. The armor belt of the "Normandie"-class ships was made from Krupp cemented armor and extended
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Normandie-class battleship. almost the entire length of the hull (), save at the stern. The belt consisted of two rows of plates that were a total of high, of which was below the waterline. The thickest portion of the armor protected the hull between the barbettes of the end turrets and was thick. Each of the upper plates was tapered to a thickness of at its top edge and the lower plates were tapered to at their bottom edge. From No. 1 barbette to the bow, the plates progressively reduced in thickness from at the bow; the upper edges also progressively reduced
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Normandie-class battleship. from while the bottom edge of these plates was thick. Aft of the rear turret, the armor plates were progressively reduced in thickness from 260 millimeters to 140 millimeters. Their upper edges also progressively thinned from and their lower edges were the same 80 millimeters in thickness as their forward equivalents. The aft belt terminated in a transverse bulkhead. Above the waterline belt was an upper strake of 160-millimeter armor that extended between the fore and aft groups of casemates for the secondary armament. The portions of the barbettes that extended outside the upper armor were protected by plates while
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Normandie-class battleship. the interior surfaces were only thick to save weight. The turrets were protected with an armor thickness of 300 millimeters on their faces, on the sides, and 100 millimeters on the roof. The sides of the conning tower were thick and its roof was also 100 millimeters thick. The lower armored deck consisted of a single plate of mild steel for a width of along the centerline and another layer of the same thickness was added outboard of that. The deck sloped downwards to meet the bottom of the waterline belt and a plate of armor steel reinforced the sloped
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Normandie-class battleship. portion of the deck to give a total thickness of . Two layers of plating made up the center of the upper armored deck and it was reinforced to a total of along the edges and above the magazine. The hull of the "Normandie"s had a double bottom deep. Their propulsion machinery spaces and magazines were protected by a torpedo bulkhead that consisted of two layers of nickel-chrome steel plates. The outer side of the bulkhead was lined with a 10-millimeter plate of corrugated flexible steel intended to absorb the force of a torpedo detonation. Another measure intended to dissipate
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Normandie-class battleship. the force were tubes that extended from the double bottom to the upper armored deck that were intended to divert the gases of the detonation away from the torpedo bulkhead. Concerned about the possibility of capsizing after asymmetric flooding, the design incorporated empty compartments below the waterline and outboard of the fore and aft 34-centimeter magazines, the engine rooms and the midships 138.6-millimeter magazines that were intended to be flooded to correct any list. Section:Construction and cancellation. "Normandie" and "Languedoc" were ordered on 18 April 1913, although neither was formally authorized until the enabling finance bill () was passed on
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Normandie-class battleship. 30 July, and "Flandre" and "Gascogne" on that same day. "Béarn" had been planned to be ordered on 1 October 1914, but it was brought forward to 1 January; the five ships would permit the creation of two four-ship divisions with the three "Bretagne"-class dreadnoughts then under construction. Work on the class was suspended at the outbreak of World War I, as all resources were needed for the Army. The mobilization in July greatly impeded construction as those workmen in the reserves were called to the colors and work was effectively halted later that month. The labor force available to
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Normandie-class battleship. work on the "Normandie"s was further reduced by conscription and orders for munitions for the Army. In light of such constraints, the navy decided that only those ships that could be completed quickly would be worked upon, like the "Brétagne"s, although construction of the first four "Normandie"s was authorized to continue to clear the slipways for other purposes. Construction of "Béarn" had been already halted on 23 July and all further work on her was abandoned. In July 1915 work on the ships' armament was suspended, save the guns themselves, which could be converted for use by the Army. Four
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Normandie-class battleship. of the completed 34 cm guns were converted into railway guns for the French Army. Nine of the guns built for "Languedoc" were also mounted on railway carriages in 1919, after the end of the war. Several of the 138.6 mm guns were also converted for service with the Army. Section:Construction and cancellation.:Progress when abandoned. The boilers intended for "Normandie" and "Gascogne" were used to replace the worn-out boilers of various destroyers, namely the purchased from Argentina in 1914 and the three "Aetos"-class ships seized from the Royal Hellenic Navy in late 1916. Those boilers built for "Flandre" were installed
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Normandie-class battleship. in new anti-submarine ships. The armor plate and turntables of "Gascogne"s turrets had been ordered from Fives-Lille, whose factory was captured by the Germans in 1914. They were discovered in one of Krupp's factories in Germany in 1921 and returned to the Navy. In January 1918, a final wartime order specified that the ships remained suspended, but that all material that had been stockpiled for work would remain in place. By that time, some of steel plating that had been earmarked for "Gascogne" had been taken for other uses. On 22 November, days after the Armistice with Germany, the design
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Normandie-class battleship. staff sent the General Staff a proposal to complete the first four "Normandie"s to a modified design. The General Staff replied that the ships would need a top speed of and a more powerful main battery. Since the dockyard facilities had not been enlarged during the war, the size of the ships could not be significantly increased. This allowed for only modest improvements, particularly for the installation of anti-torpedo bulges. In February 1919, the General Staff decided that the ships would be completed anyway, because new vessels incorporating the lessons of the war could not be completed for at least
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Normandie-class battleship. six to seven years, due to the lengthy design studies such battleships would require. The Technical Department created a revised design that incorporated some improvements. The machinery for the four ships that had been launched during the war would be retained; increasing their speed to required a corresponding increase to , which could be obtained by building new turbines. The elevation of the main guns was to be increased to 23–24 degrees, which would increase the range of the guns to lest they be out-ranged by foreign battleships. The need to engage targets at longer ranges was confirmed by the
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Normandie-class battleship. examination of one of the ex-Austrian ships that had been surrendered to France at the end of the war. The main armored deck was to be increased to to increase resistance to plunging fire. The submerged 450 mm torpedo tubes were to be replaced with deck-mounted tubes, and fire control equipment was to be improved. Equipment for handling a two-seat reconnaissance aircraft and a single-seat fighter was also to be installed. After the war, Admiral Pierre Ronarc'h became Chief of the General Staff, and in July 1919 he argued that the Italian Navy was the country's primary rival, and that
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Normandie-class battleship. they might resume work on the s that had been suspended during the war. He suggested there were three options for the first four ships: complete them as designed, increase the range of their guns and improve their armor, or lengthen their hull and install new engines to increase speed. The Technical Department determined that lengthening the hulls by could increase speed by as much as . Nevertheless, by 12 September 1919, he had decided that completing the ships would be too expensive for the fragile French economy. Plans for the first four ships included converting them into cargo ships,
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Normandie-class battleship. oil tankers, or passenger liners, and using them as floating oil depots, but these ideas were ultimately rejected. The four ships were formally cancelled in the 1922 construction program, and were laid up in Landevennec and cannibalized for parts before being broken up in 1923–1926. Much of the salvaged material was incorporated into completing "Béarn" and in modernizing the battleship . Plans to complete "Béarn" included replacement of the coal-fired boilers with eight oil-fired Niclausse boilers and new, more powerful turbines. A new quadruple turret that allowed for greater range was considered, along with twin turrets mounting guns. The battleship
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Normandie-class battleship. was launched on 15 April 1920 to clear the slip. A temporary wooden platform was built atop the lower armored deck later that year to serve as a flight deck for aircraft landing trials. Transverse arresting wires that were weighted by sandbags were improvised and the evaluation successfully took place off Toulon in late 1920. In 1922, the Navy instead decided to complete the ship as an aircraft carrier. Conversion work began in August 1923, and was completed by May 1927 using the hybrid propulsion system from "Normandie" with a dozen Normand boilers. The ship was the first carrier of
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Normandie-class battleship. the French Navy. She served in the fleet through World War II, generally being used as a ferry for aircraft; she did not see any combat as she spent most of the war in Martinique. In 1944, she was refitted in the United States and equipped with a battery of modern American anti-aircraft guns. She remained in service through the First Indochina War, still as an aircraft ferry. She was ultimately broken up for scrap starting in 1967.
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New York State Route 129. New York State Route 129 New York State Route 129 (NY 129) is a long state highway in the western part of Westchester County, New York. The route begins at New York State Route 9A (South Riverside Avenue) in the village of Croton on Hudson at the Hudson River. NY 129 then travels through the towns of Cortlandt and Yorktown, running along the northern edge of the New Croton Reservoir. It passes under (southbound) and over (northbound) the Taconic State Parkway in Yorktown with no direct interchange. NY 129 ends in Yorktown at an intersection with NY 118. NY 129
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New York State Route 129. was designated in 1908 as a section of Route 2, a legislative route designated by the New York State Legislature. However, in 1921, the route was realigned off the route that would become NY 129 in favor of NY 9A. Nine years later, the state designated the route as NY 129 during the state highway renumbering. The route originally followed a route used by NY 131 once the routes were swapped in the 1940s, with NY 131 being decommissioned soon after. NY 129 was extended to end at a traffic circle with NY 100 in the hamlet of Pines Bridge.
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New York State Route 129. This lasted up to at least 1969, when the designation was truncated back to NY 118, which was extended to the traffic circle instead. The traffic circle in Pines Bridge was removed by 1991. Originally, NY 129 had an interchange with the Taconic, but the ramps were removed in 1969 and a new interchange was built on nearby Underhill Road. Section:Route description. NY 129 begins at an intersection with NY 9A (South Riverside Avenue) in the village of Croton-on-Hudson, next to U.S. Route 9 (US 9). NY 129 proceeds northward from NY 9A along Maple Street, a two-lane commercial street
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New York State Route 129. through the village. At Van Cortlandt Park, NY 129 becomes residential, passing Croton-Harmon High School as it bends to the northeast. At the junction with Grand Street, NY 129 continues northeast on Grand Street, which is a two-lane residential street. The route continues northeast through the village, crossing an intersection with Quaker Bridge Road before becoming a wooded lane in the town of Cortlandt. In Cortlandt, NY 129 continues north as Grand Street, paralleling a local creek and entering Croton Dam Plaza. Running along the western edge of the plaza, NY 129 bends north at a view of the New
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New York State Route 129. Croton Dam, continuing its way north alongside the New Croton Reservoir. NY 129 soon changes names to Croton Dam Road, passing east of the Croton Harman School District headquarters. At an intersection with East Mount Airy Road, NY 129 runs eastward along the reservoir, changing names to Yorktown Road. On a short stint away from the reservoir, NY 129 intersects with Croton Road before crossing over the Hunters Brook Bridge, where it crosses into the historic community of Huntersville. Continuing northeast from Huntersville, NY 129, now known as Croton Lake Road, bends through the town of Yorktown. Through Yorktown, NY
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New York State Route 129. 129 is a two-lane residential street alongside the reservoir, soon making a gradual bend to the southeast into an intersection with County Route 131 (CR 131; Underhill Avenue), a former alignment of NY 131. At the junction with CR 131, NY 129 turns southward, soon winding its way southeast under the lanes of the Taconic State Parkway, and back alongside the New Croton Reservoir. After crossing under the Taconic, the route then drops back down to the reservoir and passing a house reported to have been moved from Huntersville before it was flooded. Making several winds to the southeast, NY
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New York State Route 129. 129 connects to the Gate House Bridge, soon running eastward through Yorktown. NY 129 intersects with NY 118 (Saw Mill River Road). This intersection serves as the eastern terminus of NY 129, as NY 118 continues east along the reservoir. Section:History. What is now NY 129 was developed in the early 20th century as part of a general project to improve access and transportation across the reservoirs. In 1908, the New York State Legislature created Route 2, an unsigned legislative route (an unsigned internal route) extending from the New York City line at Yonkers to the Columbia County village of
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New York State Route 129. Valatie. Route 2 initially followed modern NY 129, Croton Avenue, and NY 35 between Croton-on-Hudson and Peekskill; however, it was realigned on March 1, 1921, to use what is now NY 9A instead. NY 129 was designated to most of its current alignment as part of the 1930 renumbering of state highways in New York. It originally followed Croton Dam Road, the southern perimeter road around the New Croton Reservoir, while Croton Lake Road, the northern route, was designated as NY 131 by the following year. The alignments of NY 129 and NY 131 in the vicinity of the reservoir
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New York State Route 129. were swapped and the NY 131 designation ceased to exist by the mid-1940s. With the route changes, NY 129 was extended to terminate at NY 100 at a traffic circle in Pines Bridge while NY 118 terminated near Croton Lake. This extension lasted for over two decades until NY 118 was extended over the alignment of NY 129 to the traffic circle by 1969. Ramps from NY 129 to the Taconic State Parkway were removed by the East Hudson Parkway Authority in November 1969, to be replaced with a bridge. This required a shutdown of NY 129 and required drivers
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New York State Route 129. going north to Underhill Road. In fall 1988, the original Hunter Brook Bridge (less than wide) was replaced, as it was never designed to take heavy traffic such as concrete-mixing trucks. Between 1988 and 1991, the traffic circle between NY 118 and NY 100 was removed in favor of a three-way intersection between the two highways.
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Novara. Novara Novara (; in the local Lombard dialect) is the capital city of the province of Novara in the Piedmont region in northwest Italy, to the west of Milan. With 104 284 inhabitants (1-1-2017), it is the second most populous city in Piedmont after Turin. It is an important crossroads for commercial traffic along the routes from Milan to Turin and from Genoa to Switzerland. Novara lies between the rivers Agogna and Terdoppio in northeastern Piedmont, from Milan and from Turin. Section:History. Novara was founded in ancient times by the Romans. Its name is formed from "Nov", meaning "new", and
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Novara. "Aria", the name the Cisalpine Gauls used for the surrounding region. Ancient "Novaria", which dates to the time of the Ligures and the Celts, was a municipium and was situated on the road from Vercellae (Vercelli) to (Mediolanum) Milan. Its position on perpendicular roads (still intact today) dates to the time of the Romans. After the city was destroyed in 386 by Magnus Maximus for having supported his rival Valentinian II, it was rebuilt by Theodosius I. Subsequently, it was sacked by Radagaisus (in 405) and Attila (in 452). Under the Lombards, Novara became a duchy; under Charles the Fat,
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Novara. a countship. Novara came to enjoy the rights of a free imperial city. In 1110, it was conquered by Henry V and destroyed, but in 1167 it joined the Lombard League. At the end of the 12th century, it accepted the protection of Milan and became practically a dominion of the Visconti and later of the Sforza. In the Battle of Novara in 1513, Swiss mercenaries defending Novara for the Sforzas of Milan routed the French troops besieging the city. This defeat ended the French invasion of Italy in the War of the League of Cambrai. In 1706, Novara, which
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Novara. had long ago been promised by Filippo Maria Visconti to Amadeus VIII of Savoy, was occupied by Savoyard troops. With the Peace of Utrecht, the city, together with Milan, became part of the Habsburg Empire. After its occupation in 1734, Novara passed, in the following year, to the House of Savoy. After Napoleon's campaign in Italy, Novara became the capital of the Department of the Agogna, but was then reassigned to the House of Savoy in 1814. In 1821, it was the site of a battle in which regular Sardinian troops defeated the Piedmontese constitutional liberals. In the even larger
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Novara. Battle of Novara in 1849, the Sardinian army was defeated by the Austrian army of Field Marshal Joseph Radetzky von Radetz. This defeat led to the abdication of Charles Albert of Sardinia and to the partial occupation of the city by the Austrians. The defeat of the Sardinians can be seen as the beginning of the Italian unification movement. A decree in 1859 created the province of Novara, which then included the present-day provinces of Vercelli, Biella, and Verbano-Cusio-Ossola. The city of Novara had a population of 25,144 in 1861. Industrialisation during the 20th century brought an increase in the
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Novara. city's population to 102,088 in 1981. The city's population has changed little in subsequent years. Oscar Luigi Scalfaro, former president of Italy and Italian senator for life, was born in Novara in 1918. Section:Architecture. Novara's sights can be divided into two groupings. The city's most important sights lie within its historic centre, the area once enclosed by the city walls. However, several important sights also lie outside the line of the former city walls. Section:Architecture.:Historic centre. The old urban core makes up the "Historic centre", situated in the district of the same name. Novara once had an encircling wall, which
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Novara. was demolished to permit urban development. Of the old wall there remains only the "Barriera Albertina", a complex of two neo-classical buildings that constituted the gate of entry to the city, the required passageway for those who traveled from Turin to Milan. After their removal, the walls were replaced by the present-day "baluardi", the broad, tree-lined boulevards that surround the Historic Centre. The most imposing monument in the city is the Basilica of San Gaudenzio, with a cupola high, designed by Alessandro Antonelli and constructed in 1888. The bell tower is also of particular interest; it was designed by Benedetto
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Novara. Alfieri, uncle of the more famous Vittorio Alfieri. The centre of the religious life of the city is the Novara Cathedral, in the neo-classical style, also designed by Alessandro Antonelli. It rises exactly where the temple of Jupiter stood in the time of the Romans. Facing the Duomo is the oldest building in Novara today: the early Christian "Battistero" (Baptistry). Close to the Duomo is the courtyard of the "Broletto" (the historic meeting place of the city council), the centre of the political life of the imperial free city of Novara. Overlooking the courtyard of the Broletto are the "Palazzo
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Novara. del Podestà" ("Palace of the Podestà"), "Palazzetto dei Paratici" ("Little Palace of the Paratici Family"), site of the Civic Museum and of the Gallery of Modern Art, the Palace of the City Council, and a building of the 15th century. Not far from the Piazza della Repubblica (formerly Piazza Duomo) is the Piazza Cesare Battisti (known to Novaresi as the "Piazza delle Erbe", "Herbs square"), which constitutes the exact centre of the city of Novara. In Piazza Giacomo Matteotti stands the "Palazzo Natta-Isola", seat of the province and of the prefecture of Novara. The landmark feature of this palace is
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Novara. its clock tower. Extending from this square is the via Fratelli Rosselli, along which is the "Palazzo Cabrino", the official seat of the administrative offices of the city. As it was a Roman city, the street network of Novara is characterized by a cardo and a Decumanus Maximus, which correspond respectively to the present-day Corso Cavour and Corso Italia. The two streets cross at the so-called "Angolo delle Ore" (Corner of the Hours). The largest square is Piazza Martiri della Libertà (formerly Piazza Castello) dominated by the equestrian statue of Victor Emmanuel II, the first king of Italy. Overlooking the
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Novara. Piazza Martiri are the "Castello Visconteo-Sforzesco", built by the Milanese dukes Visconti and Sforza, and the Teatro Coccia. The Castello Visconteo-Sforzesco, once much larger than the complex that remains today, is surrounded by the "Allea", one of the largest public gardens in Novara. Other important squares are: Section:Architecture.:Outside the "Baluardi". Places of interest situated outside the belt of the "baluardi" include the Church of San Nazzaro della Costa, with its attached abbey, restored in the 15th century by Bernardino of Siena, and the Ossuary of Bicocca, in pyramidal form, which stands in the neighbourhood of Bicocca, in memory of the
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Novara. fallen soldiers of the historic battle of 23 March 1849, between the Piedmontese (Sardinia) and Austrians. Worthy of note are the Church of Santa Maria delle Grazie (Saints Martino and Gaudenzio), built beginning in 1477 by the Augustinians, whose interior consists of a single nave with lateral chapels and paintings attributed to artists of the 15th century, among them Daniele de Bosis. Section:Architecture.:Religious buildings. Section:Festivals and events. Section:Demographics. In 2007, there were 102,862 people residing in Novara, of whom 49% were male and 51% were female. Minors (children ages 18 and younger) totalled 16.35% of the population compared to pensioners
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Novara. who number 21.6%. This compares with the Italian average of 18.06% (minors) and 19.94% (pensioners). The average age of Novara residents is 44 compared to the Italian average of 42. In the five years between 2002 and 2007, the population of Novara grew by 1.64%, while Italy as a whole grew by 3.85%. The birth rate in Novara is 9.15 births per 1,000 inhabitants compared to the Italian average of 9.45 births. , 92.37% of the population was Italian. The largest immigrant group comes from other European nations: 2.94%, North Africa: 2.23%, and Latin America: 0.71%. Like most of Italy,
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Novara. Novara is predominantly Roman Catholic. Section:Economy. Novara is an important commercial centre of the Padan plain and is the seat of the Centro Intermodale Merci (CIM: Goods Intermodal Centre). Economically, it is affected by the proximity of Milan, and in fact many Milanese firms have offices in Novara. The main economic products and services are: The city of Novara is a member of the TOP-IX (Torino-Piemonte Exchange Point) internet exchange consortium, a consortium to create an Internet Exchange Point for northwestern Italy. Companies based in Novara include the publishing company De Agostini. Section:Transport. The local public transport agency is the
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Novara. SUN. Section:Transport.:Railways. The city is served by three railway stations: Section:Transport.:Motorways and main roads. Novara is linked to Turin and Milan by the A4 motorway (via the junctions Novara Ovest and Novara Est). The A26 motorway crosses most of Novara province, but there is not a junction that links it directly with Novara. To reach Novara from the A26, one must exit at Vercelli Est, but one can also reach Novara by way of the A4, which crosses the A26 at a junction. Novara is served by a system of dual-carriageway bypasses. The oldest such bypass is the Tangenziale Est,
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Novara. directly linked with the motorway junction Novara Est. In 2003, road works were completed on the Tangenziale Sud. The S11 trunk road from Milan and Magenta passes through Novara on its way to Vercelli and Turin. Trunk roads to the north and south also link Novara to the motorway network. Section:Sports. Novara Calcio is an association football club based in Novara. There is also a professional women's Serie A1 team. http://www.agilvolley.com/ Section:Government. The current mayor of Novara is Alessandro Canelli, elected in June 2016, representing a centre-right coalition. Section:Government.:Administrative subdivisions. Novara is divided into thirteen wards ("circoscrizioni"); several of these
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Novara. are formed of a number of quarters ("quartieri"), zones, and/or "frazioni" According to changes in local electoral laws, from June 2011 elections they were stripped of their elective bodies (council and president), thus remaining as a simple internal partition of the Comune. Section:Notable people. Section:Twin towns – sister cities. Novara is twinned with: Section:See also. Section:External links. br
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Origin of the domestic dog. Origin of the domestic dog The origin of the domestic dog includes the dog's evolutionary divergence from the wolf, its domestication, and its development into dog types and dog breeds. The dog is a member of the genus "Canis", which forms part of the wolf-like canids, and was the first species and the only large carnivore to have been domesticated. The dog and the extant gray wolf are sister taxa, as modern wolves are not closely related to the population of wolves that was first domesticated. The genetic divergence between dogs and wolves occurred between 40,000–20,000 years ago, just before
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Origin of the domestic dog. or during the Last Glacial Maximum. This timespan represents the upper time-limit for the commencement of domestication because it is the time of divergence and not the time of domestication, which occurred later. The domestication of animals commenced over 15,000 years ago, beginning with the grey wolf ("Canis lupus") by nomadic hunter-gatherers. The archaeological record and genetic analysis show the remains of the Bonn–Oberkassel dog buried beside humans 14,200 years ago to be the first undisputed dog, with disputed remains occurring 36,000 years ago. It was not until 11,000 years ago that people living in the Near East entered into
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Origin of the domestic dog. relationships with wild populations of aurochs, boar, sheep, and goats. Where the domestication of the dog took place remains debated, with the most plausible proposals spanning Western Europe, Central Asia and East Asia. This has been made more complicated by the recent proposal that an initial wolf population split into East and West Eurasian groups. These two groups, before going extinct, were domesticated independently into two distinct dog populations between 14,000 and 6,400 years ago. The Western Eurasian dog population was gradually and partially replaced by East Asian dogs introduced by humans at least 6,400 years ago. This proposal is
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Origin of the domestic dog. also debated. Section:Canid and human evolution. Six million years ago, towards the close of the Miocene era, the earth's climate gradually cooled. This would lead to the glaciations of the Pliocene and the Pleistocene, which are commonly referred to as the Ice Age. In many areas, forests and savannahs were replaced with steppes or grasslands, and only those species of creature that adapted to these changes would survive. In southern North America, small woodland foxes grew bigger and better adapted to running, and by the late Miocene the first of the genus "Canis" had arisen - the ancestors of coyotes,
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Origin of the domestic dog. wolves and the domestic dog. In eastern Africa, a split occurred among the large primates. Some remained in the trees, while others came down from the trees, learned to walk upright, developed larger brains, and in the more open country learned to avoid predators while becoming predators themselves. The ancestors of humans and dogs would ultimately meet in Eurasia. Human hunter-gatherers did not live in fear of nature and knew that they posed a formidable risk to any potential predators. Today, the Ju'wasi people of Namibia share their land with prides of lions. Both species coexist with respect and without
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Origin of the domestic dog. fear or hostility in a relationship that may go back to the dawn of modern humans. The lion is a much larger and far more dangerous predator than the wolf. Early modern humans entering Eurasia and first encountering packs of wolves may have been assisted in living among them because of the traditional beliefs of their African ancestors. In historical times, mutual respect and cooperation with canids can be found in the stories and traditions of the indigenous peoples of Siberia, East Asia, North America, and Australia. Section:Divergence from wolves. The domestication of animals commenced over 15,000 years before present
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Origin of the domestic dog. (YBP), beginning with the grey wolf ("Canis lupus") by nomadic hunter-gatherers. It was not until 11,000 YBP that people living in the Near East entered into relationships with wild populations of aurochs, boar, sheep, and goats. A domestication process then began to develop. The grey wolf most likely followed the commensal pathway to domestication. When, where, and how many times wolves may have been domesticated remains debated because only a small number of ancient specimens have been found, and both archaeology and genetics continue to provide conflicting evidence. The most widely accepted, earliest dog remains date back 15,000 YBP to
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Origin of the domestic dog. the Bonn–Oberkassel dog. Earlier remains dating back to 30,000 YBP have been described as Paleolithic dogs, however their status as dogs or wolves remains debated. Recent studies indicate that a genetic divergence occurred between dogs and wolves 20,000-40,000 YBP, however this is the upper time-limit for domestication because it represents the time of divergence and not the time of domestication. Section:Divergence from wolves.:Time of genetic divergence. The date estimated for the evolutionary divergence of a domestic lineage from a wild one does not necessarily indicate the start of the domestication process but it does provide an upper boundary. The divergence
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Origin of the domestic dog. of the lineage that led to the domestic horse from the lineage that led to the modern Przewalski's horse is estimated to have occurred around 45,000 YBP but the archaeological record indicates 5,500 YBP. The variance can be due to modern wild populations not being the direct ancestor of the domestic ones, or to a divergence caused by changes in the climate, topography, or other environmental influences. The evolutionary divergence time for the wolf and dog is indicated to have occurred somewhere between 20,000-60,000 YBP but this does not imply that domestication occurred during this period. Section:Divergence from wolves.:Time of
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Origin of the domestic dog. genetic divergence.:Paleobiogeography. During the Late Pleistocene glaciation, a vast mammoth steppe stretched from Spain eastwards across Eurasia and over the Bering land bridge into Alaska and the Yukon. The Late Pleistocene was characterized by a series of severe and rapid climate oscillations with regional temperature changes of up to , which has been correlated with megafaunal extinctions. There is no evidence of megafaunal extinctions at the height of the Last Glacial Maximum, indicating that increasing cold and glaciation were not factors. Multiple events appear to have caused the rapid replacement of one species by another one within the same genus,
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Origin of the domestic dog. or one population by another within the same species, across a broad area. As some species became extinct, so too did the predators that depended on them. The origin of dogs is couched in the paleobiogeography of wolf populations during the Late Pleistocene. The earliest fossils of "Canis lupus" were found in what was once eastern Beringia at Old Crow, Yukon, Canada and at Cripple Creek Sump, Fairbanks, Alaska. The age is not agreed but could date 1 million YBP. Considerable morphological diversity existed among grey wolves by the Late Pleistocene. These are regarded as having been more cranio-dentally robust
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Origin of the domestic dog. than modern grey wolves, often with a shortened rostrum, the pronounced development of the temporalis muscle, and robust premolars. It is proposed that these features were specialized adaptations for the processing of carcass and bone associated with the hunting and scavenging of Pleistocene megafauna. Compared with modern wolves, some Pleistocene wolves showed an increase in tooth breakage that is similar to that seen in the extinct dire wolf. This suggests that these either often processed carcasses, or that they competed with other carnivores and needed to quickly consume their prey. The frequency and location of tooth fractures found in these
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Origin of the domestic dog. wolves compared with the modern spotted hyena indicates that these wolves were habitual bone crackers. Section:Divergence from wolves.:Time of genetic divergence.:Timespan. Genetic studies indicate that the gray wolf is the closest living relative of the dog, with no evidence of any other canine species having contributed. Attempting to reconstruct the dog's lineage through the phylogenetic analysis of DNA sequences from modern dogs and wolves has given conflicting results for several reasons. Firstly, studies indicate that an extinct Late Pleistocene wolf is the nearest common ancestor to the dog, with modern wolves not being the dog's direct ancestor. Secondly, the genetic
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Origin of the domestic dog. divergence between the dog and modern wolves occurred over a short period of time, so that the time of the divergence is difficult to date (referred to as incomplete lineage sorting). This is complicated further by the cross-breeding that has occurred between dogs and wolves since domestication (referred to as post-domestication gene flow). Finally, there have been only tens of thousands of generations of dogs since domestication, so that the number of mutations between the dog and the wolf are few and this makes the timing of domestication difficult to date. In 2013, the whole genome sequencing of modern dogs
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Origin of the domestic dog. and wolves indicated a divergence time of 32,000 YBP. In 2014, another study indicated 16,000-11,000 YBP. The first draft genome sequence of a Pleistocene canid was published in 2015. This Taymyr Peninsula wolf belonged to a population that had diverged from the ancestors of both modern wolves and dogs. Radiocarbon dating indicates its age to be 35,000 YBP, and this age could then be used to re-calibrate the wolf's mutation rate, indicating that the genetic divergence between dogs and wolves occurred before the Last Glacial Maximum, between 40,000–27,000 YBP. When this mutation rate was applied to the timing of the
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Origin of the domestic dog. 2014 study, that study gave the same result of 40,000–27,000 YBP. Section:Divergence from wolves.:Place of genetic divergence. Most genetic studies conducted over the last two decades were based on modern dog breeds and extant wolf populations, with their findings dependent on a number of assumptions. These studies assumed that the extant wolf was the ancestor of the dog, did not consider genetic admixture between wolves and dogs, nor the impact of incomplete lineage sorting. These pre-genomic studies have suggested an origin of dogs in Southeast Asia, East Asia, Central Asia, the Middle East, or Europe. More recently, the field of
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Origin of the domestic dog. Paleogenomics applies the latest molecular technologies to fossil remains that still contain useful DNA. Section:Divergence from wolves.:Place of genetic divergence.:Europe. In 2013, a study sequenced the complete mitochondrial genomes of 18 fossil canids and these were then compared with the mitochondrial genomes from modern wolves and dogs in a phylogenetic tree. The study found that there exists more genetic variation between the 18 fossil canids than exists between all modern wolves and dogs. The analyses included the oldest fossils proposed as early dogs dating back as far as 36,000 YBP. However, these Goyet Cave canids were found to have formed
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24853562
Origin of the domestic dog. an ancient and extinct sister group to modern dogs and wolves. The authors propose that these dog-like fossils were either an early domestication attempt that left no descendants among modern dogs, or that they were a specialized wolf ecomorph whose morphological features were part of the Late Pleistocene wolf diversity. An earlier study of the Razboinichya Cave canid that was based on a segment of its mitochondrial DNA (mDNA) had concluded that it was an early dog. This fossil was included for the analysis of its complete mitochondrial genome and on the phylogenetic tree was assigned a much more basal
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Origin of the domestic dog. position. The study inferred from the tree that dogs and wolves split 32,000-19,000 YBP and therefore the beginning of domestication occurred in the time of hunter-gatherers rather than in the time of farmers. The tree also confirmed that the ancient dogs of the Americas originated in Eurasia. The phylogenetic analyses revealed that three of the four major mDNA clades of dogs relate most closely to the ancient canids from Europe rather than those from China or the Middle East, which supports a European origin of modern dogs. No modern wolf population related closer to dogs than the ancient canids from
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Origin of the domestic dog. Europe, indicating that the wolf population that was the ancestor of the dog is extinct. Section:Divergence from wolves.:Place of genetic divergence.:Arctic northeastern Siberia. In 2015, a study recovered mDNA from ancient canid specimens that were discovered in arctic northeastern Siberia (which was once western Beringia). These specimens included the mandible of a 360,000-400,000 YBP "Canis c.f. variabilis" (where c.f. is a Latin term meaning uncertain). Phylogenetic analyses of these canids revealed nine mDNA haplotypes not detected before. The "Canis c.f. variabilis" specimen clustered with other wolf samples from across Russia and Asia. The mDNA haplotypes of one 8,750 YBP specimen
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Origin of the domestic dog. and some 28,000 YBP specimens matched with those of geographically widely-spread modern dogs. One 47,000 YBP canid was distinct from wolves but was only a few mutations away from those haplotypes found in modern dogs. The authors concluded that the structure of the modern dog gene pool was contributed to from ancient Siberian wolves and possibly from "Canis c.f. variabilis". Section:Divergence from wolves.:Place of genetic divergence.:Two origins. Dogs show both ancient and modern lineages. The ancient lineages appear most in Asia but least in Europe because the Victorian era development of modern dog breeds used little of the ancient lineages.
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Origin of the domestic dog. All dog populations (breed, village, and feral) show some evidence of genetic admixture between modern and ancient dogs. Some ancient dog populations that once occupied Europe and the New World no longer exist. This implies that some ancient dog populations were entirely replaced and others admixed over a long period of time. European dog populations have undergone extensive turnover during the last 15,000 years which has erased the genomic signature of early European dogs, the genetic heritage of the modern breeds has become blurred due to admixture, and there was the possibility of past domestication events that had gone extinct
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Origin of the domestic dog. or had been largely replaced by more modern dog populations. Siberian huskies and other northern breeds can trace at least some of their ancestry (1.4–27.3%) back to the Taimyr wolf, which indicates the possibility of more than one domestication event. In 2016, a study compared the mitochondrial DNA and whole-genome sequences of a worldwide panel of modern dogs, the mDNA sequences of 59 ancient European dog specimens dated 14,000-3,000 YBP, and the nuclear genome sequence of a dog specimen that was found in the Late Neolithic passage grave at Newgrange, Ireland and radiocarbon dated at 4,800 YBP. A genetic analysis
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Origin of the domestic dog. of the Newgrange dog showed that it was male, did not possess genetic variants associated with modern coat length nor color, was not as able to process starch as efficiently as modern dogs but more efficiently than wolves, and showed ancestry from a population of wolves that could not be found in other dogs nor wolves today. As the taxonomic classification of the "proto-dog" Paleolithic dogs as being either dogs or wolves remains controversial, they were excluded from the study. The phylogenetic tree generated from mDNA sequences found a deep division between the Sarloos wolfdog and all other dogs, indicating
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Origin of the domestic dog. that breed's recent deriving from the German Shepherd and captive gray wolves. The next largest division was between eastern Asian dogs and western Eurasian (Europe and the Middle East) dogs that had occurred between 14,000-6,400 YBP, with the Newgrange dog clustering with the western Eurasian dogs. The Newgrange and ancient European dog mDNA sequences could be largely assigned to mDNA haplogroups C and D but modern European dog sequences could be largely assigned to mDNA haplogroups A and B, indicating a turnover of dogs in the past from a place other than Europe. As this split dates older than the
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Origin of the domestic dog. Newgrange dog this suggests that the replacement was only partial. The analysis showed that most modern European dogs had undergone a population bottleneck (reduction) which can be an indicator of travel. The archaeological record shows dog remains dating over 15,000 YBP in western Eurasia, over 12,500 YBP in eastern Eurasia, but none older than 8,000 YBP in Central Asia. The study proposes that dogs may have been domesticated separately in both eastern and western Eurasia from two genetically distinct and now extinct wolf populations. East Eurasian dogs then made their way with migrating people to western Europe between 14,000-6,400 YBP
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Origin of the domestic dog. where they partially replaced the dogs of Europe. Two domestication events in western Eurasia and eastern Eurasia has recently been found for the domestic pig. The hypothesis is that two genetically different, and possibly now extinct, wolf populations were domesticated independently in eastern and western Eurasia to produce paleolithic dogs. The eastern Eurasian dogs then dispersed westward alongside humans, reaching western Europe 6,400–14,000 years ago where they partially replaced the western paleolithic dogs. A single domestication is thought to be due to chance, however dual domestication on different sides of the world is unlikely to have happened randomly and it
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Origin of the domestic dog. suggests that external factors - an environmental driver - may have forced wolves to work together with humans for survival. It is possible that wolves took advantage of resources that humans had, or humans may have been introduced to wolves in an area in which they didn't previously live. The study indicates that the western Eurasian wolf and dog populations genetically diverged 20,000-60,000 YBP. Immediately after this divergence, the dog population outnumbered the wolf population, and later the dog population underwent a population reduction to be much lower. Section:Divergence from wolves.:Place of genetic divergence.:Two origins disputed. In 2017, a study
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Origin of the domestic dog. compared the nuclear genome sequences of three ancient dog specimens from Germany and Ireland with sequences from over 5,000 dogs and wolves. These Neolithic dog specimens included a dog sample from the Early Neolithic site in Herxheim, Germany dated 7,000 YBP, one from the Late Neolithic site of Kirschbaum (Cherry Tree) Cave near Forchheim, Germany dated 4,700 YBP, and a dog from Newgrange, Ireland dated 4,800 YBP. The study found that modern European dogs descended from their Neolithic ancestors with no evidence of a population turnover. There was evidence of a single dog-wolf divergence occurring between 36,900-41,500 YBP, followed by
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Origin of the domestic dog. a divergence between Southeast Asian and Western Eurasian dogs 17,500-23,900 YBP and this indicates a single dog domestication event occurring between 20,000-40,000 YBP. The 3 dogs indicated ancestry that could be found in South East Asian dogs. Additionally, the Cherry Tree Cave dog showed ancestry that could be found in the Middle East, India and Central Asia. The study did not support a dual domestication event, and detected admixture between the ancestors of modern European and Southeast Asian dogs. A 2018 study of mDNA sequences shows that the pre-Neolithic dogs of Europe all fell under haplogroup C. The Neolithic and
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Origin of the domestic dog. Post-Neolithic dogs from Southeastern Europe that are associated with farmers fell under haplogroup D. In Western and Northern Europe, haplogroup D became diluted into the native dog population. This implies that haplogroup D arrived in Europe 9,000 years ago from the Near East along with pigs, cows, sheep, and goats. Later in 2018, another study looked at the y-chromosome male lineage of the ancient fossils of the Herxheim, Kirschbaum, and Newgrange dogs along with other canines. The study identified six major dog yDNA haplogroups, of which two of these include the majority of modern dogs. The Newgrange dog fell into
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Origin of the domestic dog. the most commonly occurring of these haplogroups. The two ancient German dogs fell into a haplogroup commonly found among dogs from the Middle East and Asia, with the Kirschbaum dog sharing a common male lineage with the extant Indian wolf. The study concluded that at least 2 different male haplogroups existed in ancient Europe, and that the dog male lineage diverged from its nearest common ancestor shared with the gray wolf sometime between 68,000-151,000 YBP. Section:Divergence from wolves.:Morphological divergence. The questions of when and where dogs were first domesticated have taxed geneticists and archaeologists for decades. Identifying the earliest dogs
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Origin of the domestic dog. is difficult because the key morphological characters that are used by zooarchaeologists to differentiate domestic dogs from their wild wolf ancestors (size and position of teeth, dental pathologies, and size and proportion of cranial and postcranial elements) were not yet fixed during the initial phases of the domestication process. The range of natural variation among these characters that may have existed in ancient wolf populations, and the time it took for these traits to appear in dogs, are unknown. Section:Divergence from wolves.:Morphological divergence.:Early dog specimens. There are a number of recently discovered specimens which are proposed as being Paleolithic dogs,
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Origin of the domestic dog. however their taxonomy is debated. These have been found in either Europe or Siberia and date 40,000-17,000 YBP. They include Hohle Fels in Germany, Goyet Caves in Belgium, Predmosti in the Czech Republic, and four sites in Russia: Razboinichya Cave in the Altai Republic, Kostyonki-8, Ulakhan Sular in the Sakha Republic, and Eliseevichi 1 on the Russian plain. Paw-prints from Chauvet Cave in France dated 26,000 YBP are suggested as being those of a dog, however these have been challenged as being left by a wolf. There are also a number of later proposed Paleolithic dogs whose taxonomy has not
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Origin of the domestic dog. been confirmed. These include a number of specimens from Germany (Kniegrotte, Oelknitz, Teufelsbrucke), Switzerland (Monruz, Kesslerloch, Champre-veyres-Hauterive), and Ukraine (Mezin, Mezhirich). A set of specimens dating 15,000-13,500 YBP have been confidently identified as domesticated dogs, based on their morphology and the archaeological sites in which they have been found. These include Spain (Erralla), France (Montespan, Le Morin, Le Closeau, Pont d’Ambon), and Germany (Bonn-Oberkassel). After this period, the remains of domesticated dogs have been identified from archaeological sites across Eurasia. Possible dog domestication between 40,000-15,000 years ago is not clear due to the debate over what the Paleolithic dog specimens
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Origin of the domestic dog. represent. This is due to the flexibility of genus "Canis" morphology, and the close morphological similarities between "Canis lupus" and "Canis familiaris". It is also due to the scarcity of Pleistocene wolf specimens available for analyses and so their morphological variation is unknown. Habitat type, climate, and prey specialization greatly modify the morphological plasticity of grey wolf populations, resulting in a range of morphologically, genetically, and ecologically distinct wolf morphotypes. With no baseline to work from, zooarchaeologists find it difficult to be able to differentiate between the initial indicators of dog domestication and various types of Late Pleistocene wolf ecomorphs,
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Origin of the domestic dog. which can lead to the mis-identification of both early dogs and wolves. Additionally, the ongoing prehistoric admixture with local wolf populations during the domestication process may have led to canids that were domesticated in their behavior but wolflike in their morphology. Attempting to identify early tamed wolves, wolfdogs, or proto-dogs through morphological analysis alone may be impossible without the inclusion of genetic analyses. A domestication study looked at the reasons why the archeological record that is based on the dating of fossil remains often differed from the genetic record contained within the cells of living species. The study concluded that
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Origin of the domestic dog. our inability to date domestication is because domestication is a continuum and there is no single point where we can say that a species was clearly domesticated using these two techniques. The study proposes that changes in morphology across time and how humans were interacting with the species in the past needs to be considered in addition to these two techniques. Section:Dog domestication. The earlier association of dogs with humans may have allowed dogs to have a profound influence on the course of early human history and the development of civilization. However, the timing, geographic locations, and ecological conditions that
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Origin of the domestic dog. led to dog domestication are not agreed. There is clear evidence that dogs were derived from gray wolves during the initial phases of domestication and that no other canine species was involved. The wolf population(s) that were involved are likely to be extinct. Despite numerous genetic studies of both modern dogs and ancient dog remains, there is no firm consensus regarding either the timing or location(s) of domestication, the number of wolf populations that were involved, or the long-term effects domestication has had on the dog's genome. Genetic studies suggest a domestication process commencing over 25,000 YBP, in one or
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Origin of the domestic dog. several wolf populations in either Europe, the high Arctic, or eastern Asia. The remains of large carcasses left by human hunter-gatherers may have led some wolves into entering a migratory relationship with humans. This could have led to their divergence from those wolves that remained in the one territory. A closer relationship between these wolves — or proto-dogs — and humans may have then developed, such as hunting together and mutual defence from other carnivores and other humans. Around 10,000 YBP agriculture was developed resulting in a sedentary lifestyle, along with phenotype divergence of the dog from its wolf ancestors,
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Origin of the domestic dog. including variance in size. In the Victorian era, directed human selection developed the modern dog breeds, which resulted in a vast range of phenotypes. Each of these domestication phases have left their mark on the dog's genome. Genetic studies support two population bottlenecks having occurred to the dog lineage, one due to the initial domestication and one due to the formation of dog breeds. Section:Dog domestication.:Time of domestication. An apex predator is a predator that sits on the top trophic level of the food chain, while a mesopredator sits further down the food chain and is dependent on smaller animals.
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Origin of the domestic dog. Towards the end of the Pleistocene era, most of today's apex predators were mesopredators and this included the wolf. During the ecological upheaval associated with the close of the Late Pleistocene, one type of wolf population rose to become today's apex predator and another joined with humans to become an apex consumer. In August 2015, a study undertook an analysis of the complete mitogenome sequences of 555 modern and ancient dogs. The sequences showed an increase in the population size approximately 23,500 YBP, which broadly coincides with the proposed separation of the ancestors of dogs and present-day wolves before the
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Origin of the domestic dog. Last Glacial Maximum (refer first divergence). A ten-fold increase in the population size occurred after 15,000 YBP, which may be attributable to domestication events and is consistent with the demographic dependence of dogs on the human population. Section:Dog domestication.:Socialization. Humans and wolves both exist in complex social groups. How humans and wolves got together remains unknown. One view holds that domestication as a process that is difficult to define. The term was developed by anthropologists with a human-centric view in which humans took wild animals (ungulates) and bred them to be "domestic", usually in order to provide improved food or
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Origin of the domestic dog. materials for human consumption. That term may not be appropriate for a large carnivore such as the dog. This alternate view regards dogs as being either socialized and able to live among humans, or unsocialized. There exists today dogs that live with their human families but are unsocialized and will threaten strangers defensively and aggressively no different from a wild wolf. There also exists a number of cases where wild wolves have approached people in remote places, attempting to initiate play and to form companionship. One such notable wolf was Romeo, a gentle black wolf that formed relationships with the
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Origin of the domestic dog. people and dogs of Juneau, Alaska. This view holds that before there could have been domestication of the wolf, there had to have been its socialization. Section:Dog domestication.:Commensal pathway. Animal domestication is a coevolutionary process in which a population responds to selective pressure while adapting to a novel niche that included another species with evolving behaviors. The dog is a classic example of a domestic animal that likely traveled a commensal pathway into domestication. The dog was the first domesticant, and was domesticated and widely established across Eurasia before the end of the Pleistocene, well before cultivation or the domestication
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Origin of the domestic dog. of other animals. It may have been inevitable that the first domesticated animal came from the order of carnivores as these are less afraid when approaching other species. Within the carnivores, the first domesticated animal would need to exist without an all-meat diet, possess a running and hunting ability to provide its own food, and be of a controllable size to coexist with humans, indicating the family "Canidae", and the right temperament with wolves being among the most gregarious and cooperative animals on the planet. Ancient DNA supports the hypothesis that dog domestication preceded the emergence of agriculture and was
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Origin of the domestic dog. initiated close to the Last Glacial Maximum 27,000 YBP when hunter-gatherers preyed on megafauna, and when proto-dogs might have taken advantage of carcasses left on site by early hunters, assisted in the capture of prey, or provided defense from large competing predators at kill-sites. Wolves were probably attracted to human campfires by the smell of meat being cooked and discarded refuse in the vicinity, first loosely attaching themselves and then considering these as part of their home territory where their warning growls would alert humans to the approach of outsiders. The wolves most likely drawn to human camps were the
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Origin of the domestic dog. less-aggressive, subdominant pack members with lowered flight response, higher stress thresholds, less wary around humans, and therefore better candidates for domestication. The earliest sign of domestication in dogs was the neotenization of skull morphology and the shortening of snout length that results in tooth crowding, reduction in tooth size, and a reduction in the number of teeth, which has been attributed to the strong selection for reduced aggression. This process may have begun during the initial commensal stage of dog domestication, even before humans began to be active partners in the process. A maternal mitochondrial, paternal Y chromosome, and microsatellite
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Origin of the domestic dog. assessment of two wolf populations in North America and combined with satellite telemetry data revealed significant genetic and morphological differences between one population that migrated with and preyed upon caribou, and another territorial ecotype population that remained in a boreal coniferous forest. Though these two populations spend a period of the year in the same place, and though there was evidence of gene flow between them, the difference in prey–habitat specialization has been sufficient to maintain genetic and even coloration divergence. A study has identified the remains of a population of extinct Pleistocene Beringian wolves with unique mitochondrial signatures. The
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Origin of the domestic dog. skull shape, tooth wear, and isotopic signatures suggested these were specialist megafauna hunters and scavengers that became extinct while less specialized wolf ecotypes survived. Analogous to the modern wolf ecotype that has evolved to track and prey upon caribou, a Pleistocene wolf population could have begun following mobile hunter-gatherers, thus slowly acquiring genetic and phenotypic differences that would have allowed them to more successfully adapt to the human habitat. Even today, the wolves on Ellesmere Island do not fear humans, which is thought to be due to them seeing humans so little, and they will approach humans cautiously, curiously and
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Origin of the domestic dog. closely. Section:Dog domestication.:Post-domestication gene flow. Since domestication, dogs have traveled alongside humans across most of the planet, often hybridizing with local wild canids. This has resulted in complex patterns of ancient and recent admixture among both the wild and the domestic canids. Some studies have found greater diversity in the genetic markers of dogs from East and Central Asia compared to Europe and have concluded that dogs originated from these regions, despite no archaeological evidence to support the conclusions. One reason for these discrepancies is the sustained admixture between different dog and wolf populations across the Old and New Worlds
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Origin of the domestic dog. over at least the last 10,000 years, which has blurred the genetic signatures and confounded efforts of researchers at pinpointing the origins of dogs. Another reason is that none of the modern wolf populations are related to the Pleistocene wolves that were first domesticated. In other words, the extinction of the wolves that were the direct ancestors of dogs has muddied efforts to pinpoint the time and place of dog domestication. Section:Dog domestication.:Post-domestication gene flow.:Dog-Wolf admixture. There is evidence of admixture between dog and regional wolf populations, except on the Tibetan Plateau and in the New World wolves. This admixture
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Origin of the domestic dog. has occurred throughout history and as dogs expanded across the landscape. There are some dog populations that show recent admixture with wolves. Phylogenetic analysis shows that modern dog mDNA haplotypes resolve into four monophyletic clades with strong statistical support, and these have been designated by researchers as clades A-D. Other studies that included a wider sample of specimens have reported two rare East Asian clades E-F with weaker statistical support. In 2009, a study found that haplogroups A, B and C included 98% of dogs and are found universally distributed across Eurasia, indicating that they were the result of a
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Origin of the domestic dog. single domestication event, and that haplogroups D, E, and F were rare and appeared to be the result of regional hybridization with local wolves post-domestication. Haplogroups A and B contained subclades that appeared to be the result of hybridization with wolves post-domestication, because each haplotype within each of these subclades was the result of a female wolf/male dog pairing. Haplogroup A: Includes 64-65% of dogs. Haplotypes of subclades a2–a6 are derived from post-domestication wolf–dog hybridization. Haplogroup B: Includes 22-23% of dogs. haplotypes of subclade b2 are derived from post-domestication wolf–dog hybridization. Haplogroup C: Includes 10-12% of dogs. Haplogroup D: Derived
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