A pig is any of the animals in the genus Sus, within the even-toed ungulate family Suidae. Pigs include the domestic pig and its ancestor, the common Eurasian wild boar, along with other species. Related creatures outside the genus include the peccary, the babirusa, the warthog. Pigs, like all suids, are native to the African continents. Juvenile pigs are known as piglets. Pigs are social and intelligent animals. With around 1 billion individuals alive at any time, the domestic pig is among the most populous large mammals in the world. Pigs can consume a wide range of food. Pigs are biologically similar to humans and are thus used for human medical research; the Online Etymology Dictionary provides anecdotal evidence as well as linguistic, saying that the term derives from Old English *picg, found in compounds, ultimate origin unknown. "young pig". Related to Low German bigge, Dutch big.... Another Old English word for "pig" was fearh, related to furh "furrow," from PIE *perk- "dig, furrow". "This reflects a widespread IE tendency to name animals from typical attributes or activities".
Synonyms grunter, oinker are from sailors' and fishermen's euphemistic avoidance of uttering the word pig at sea, a superstition based on the fate of the Gadarene swine, who drowned. The Online Etymology Dictionary traces the evolution of sow, the term for a female pig, through various historical languages: Old English sugu, su "female of the swine," from Proto-Germanic *su-, from PIE root *su- imitative of pig noise, it is likely that the word to call pigs, "soo-ie," is derived. An adjectival form is porcine. Another adjectival form is suine. A typical pig has a large head with a long snout, strengthened by a special prenasal bone and by a disk of cartilage at the tip; the snout is used to dig into the soil to find food and is a acute sense organ. There are four hoofed toes on each foot, with the two larger central toes bearing most of the weight, but the outer two being used in soft ground; the dental formula of adult pigs is 220.127.116.11.1.4.3. The rear teeth are adapted for crushing. In the male, the canine teeth form tusks, which grow continuously and are sharpened by being ground against each other.
Captive mother pigs may savage their own piglets if they become stressed. Some attacks on newborn piglets are non-fatal. Others may cause the death of the piglets and sometimes, the mother may eat the piglets, it is estimated that 50% of piglet fatalities are due to the mother attacking, or unintentionally crushing, the newborn pre-weaned animals. With around 1 billion individuals alive at any time, the domestic pig is one of the most numerous large mammals on the planet; the ancestor of the domestic pig is the wild boar, one of the most numerous and widespread large mammals. Its many subspecies are native to all but the harshest climates of continental Eurasia and its islands and Africa as well, from Ireland and India to Japan and north to Siberia. Long isolated from other pigs on the many islands of Indonesia and the Philippines, pigs have evolved into many different species, including wild boar, bearded pigs, warty pigs. Humans have introduced pigs into Australia and South America, numerous islands, either accidentally as escaped domestic pigs which have gone feral, or as wild boar.
The wild pig can take advantage of any forage resources. Therefore, it can live in any productive habitat that can provide enough water to sustain large mammals such as pigs. If there is increased foraging of wild pigs in certain areas, it can cause a nutritional shortage which can cause the pig population to decrease. If the nutritional state returns to normal, the pig population will most rise due to the pigs' increased reproduction rate. Pigs are omnivores, which means that they consume both animals. In the wild, they are foraging animals eating leaves, roots and flowers, in addition to some insects and fish; as livestock, pigs are fed corn and soybean meal with a mixture of vitamins and minerals added to the diet. Traditionally, they were raised on dairy farms and called "mortgage lifters", due to their ability to use the excess milk as well as whey from cheese and butter making combined with pasture. Older pigs will consume three to five gallons of water per day; when kept as pets, the optimal healthy diet consists of a balanced diet of raw vegetables, although some may give their pigs conventional mini pig pellet feed.
Domesticated pigs miniature breeds, are kept as pets. Domestic pigs are raised commercially as livestock; because of their foraging abilities and excellent sense of smell, they are used to find truffles in many European countries. Both wild and feral pigs are hunted; the short, coarse hairs of the pig are called brist
Sericulture, or silk farming, is the cultivation of silkworms to produce silk. Although there are several commercial species of silkworms, Bombyx mori is the most used and intensively studied silkworm. Silk was believed to have first been produced in China as early as the Neolithic period. Sericulture has become an important cottage industry in countries such as Brazil, France, Italy, Japan and Russia. Today and India are the two main producers, with more than 60% of the world's annual production. According to Confucian text, the discovery of silk production dates to about 2700 BC, although archaeological records point to silk cultivation as early as the Yangshao period. In 1977, a piece of ceramic created 5400–5500 years ago and designed to look like a silkworm was discovered in Nancun, providing the earliest known evidence of sericulture. By careful analysis of archaeological silk fibre found on Indus Civilization sites dating back to 2450–2000 BC, it is believed that silk was being used over a wide region of South Asia.
By about the first half of the 1st century AD it had reached ancient Khotan, by a series of interactions along the Silk Road. By 140 AD the practice had been established in India. In the 6th century the smuggling of silkworm eggs into the Byzantine Empire led to its establishment in the Mediterranean, remaining a monopoly in the Byzantine Empire for centuries. In 1147, during the Second Crusade, Roger II of Sicily attacked Corinth and Thebes, two important centres of Byzantine silk production, capturing the weavers and their equipment and establishing his own silkworks in Palermo and Calabria spreading the industry to Western Europe. Chinese sericulture process Silkworm larvae are fed with mulberry leaves, after the fourth moult, they climb a twig placed near them and spin their silken cocoons; the silk is a continuous filament comprising fibroin protein, secreted from two salivary glands in the head of each larva, a gum called sericin, which cements the filaments. The sericin is removed by placing the cocoons in hot water, which frees the silk filaments and readies them for reeling.
This is known as the degumming process. The immersion in hot water kills the silkworm pupa. Single filaments are combined to form thread, drawn under tension through several guides and wound onto reels; the threads may be plied to form yarn. After drying, the raw silk is packed according to quality; the stages of production are as follows: The silk moth lays 300 to 500 eggs. The silk moth eggs hatch to form larvae or caterpillars, known as silkworms; the larvae feed on mulberry leaves. Having grown and moulted several times, the silkworm extrudes a silk fibre and forms a net to hold itself, it swings itself from side to side in a figure' 8' distributing the saliva. The silk solidifies; the silkworm spins one mile of filament and encloses itself in a cocoon in about two or three days. The amount of usable quality silk in each cocoon is small; as a result, about 2500 silkworms are required to produce a pound of raw silk. The intact cocoons are boiled; the silk is obtained by brushing the undamaged cocoon to find the outside end of the filament.
The silk filaments are wound on a reel. One cocoon contains 1,000 yards of silk filament; the silk at this stage is known as raw silk. One thread comprises up to 48 individual silk filaments. Mahatma Gandhi was critical of silk production based on the Ahimsa philosophy "not to hurt any living thing", he promoted "Ahimsa silk", made without boiling the pupa to procure the silk and wild silk made from the cocoons of wild and semi-wild silk moths. The Human League criticised sericulture in their early single "Being Boiled". In the early 21st century the organisation PETA has campaigned against silk. Good agricultural practices Magnanery Silk industry in Azerbaijan Silk industry in China Smithsonian sericulture history Silk Production Process Silk worm Life cycle photos Raising silkworms in your classroom, including photos
Pottery is the process of forming vessels and other objects with clay and other ceramic materials, which are fired to give them a hard, durable form. Major types include earthenware and porcelain; the place where such wares are made by a potter is called a pottery. The definition of pottery used by the American Society for Testing and Materials, is "all fired ceramic wares that contain clay when formed, except technical and refractory products." In archaeology of ancient and prehistoric periods, "pottery" means vessels only, figures etc. of the same material are called "terracottas". Clay as a part of the materials used is required by some definitions of pottery, but this is dubious. Pottery is one of the oldest human inventions, originating before the Neolithic period, with ceramic objects like the Gravettian culture Venus of Dolní Věstonice figurine discovered in the Czech Republic dating back to 29,000–25,000 BC, pottery vessels that were discovered in Jiangxi, which date back to 18,000 BC.
Early Neolithic pottery artefacts have been found in places such as Jōmon Japan, the Russian Far East, Sub-Saharan Africa and South America. Pottery is made by forming a ceramic body into objects of a desired shape and heating them to high temperatures in a kiln and induces reactions that lead to permanent changes including increasing the strength and solidity of the object's shape. Much pottery is purely utilitarian, but much can be regarded as ceramic art. A clay body can be decorated after firing. Clay-based pottery can divided in three main groups: earthenware and porcelain; these require more specific clay material, higher firing temperatures. All three are made for different purposes. All may be decorated by various techniques. In many examples the group a piece belongs to is visually apparent, but this is not always the case; the fritware of the Islamic world does not use clay, so technically falls outside these groups. Historic pottery of all these types is grouped as either "fine" wares expensive and well-made, following the aesthetic taste of the culture concerned, or alternatively "coarse", "popular" "folk" or "village" wares undecorated, or so, less well-made.
All the earliest forms of pottery were made from clays that were fired at low temperatures in pit-fires or in open bonfires. They were hand undecorated. Earthenware can be fired as low as 600°C, is fired below 1200°C; because unglazed biscuit earthenware is porous, it has limited utility for the storage of liquids, eating off. However, earthenware has a continuous history from the Neolithic period to today, it can be made from a wide variety of clays, some of which fire to a buff, brown or black colour, with iron in the constituent minerals resulting in a reddish-brown. Reddish coloured varieties are called terracotta when unglazed or used for sculpture; the development of ceramic glaze which makes it impermeable makes it a popular and practical form of pottery. The addition of decoration has evolved throughout its history. Stoneware is pottery, fired in a kiln at a high temperature, from about 1,100°C to 1,200°C, is stronger and non-porous to liquids; the Chinese, who developed stoneware early on, classify this together with porcelain as high-fired wares.
In contrast, stoneware could only be produced in Europe from the late Middle Ages, as European kilns were less efficient, the right sorts of clay less common. It remained a speciality of Germany until the Renaissance. Stoneware is tough and practical, much of it has always been utilitarian, for the kitchen or storage rather than the table, but "fine" stoneware has been important in China and the West, continues to be made. Many utilitarian types have come to be appreciated as art. Porcelain is made by heating materials including kaolin, in a kiln to temperatures between 1,200 and 1,400 °C; this is higher than used for the other types, achieving these temperatures was a long struggle, as well as realizing what materials were needed. The toughness and translucence of porcelain, relative to other types of pottery, arises from vitrification and the formation of the mineral mullite within the body at these high temperatures. Although porcelain was first made in China, the Chinese traditionally do not recognise it as a distinct category, grouping it with stoneware as "high-fired" ware, opposed to "low-fired" earthenware.
This confuses the issue of. A degree of translucency and whiteness was achieved by the Tang Dynasty, considerable quantities were being exported; the modern level of whiteness was not reached until much in the 14th century. Porcelain was made in Korea and in Japan from the end of the 16th century, after suitable kaolin was located in those countries, it was not made outside East Asia until the 18th century. Before being shaped, clay must be prepared. Kneading helps to ensure an moisture content throughout the body. Air trapped within the clay body needs to be removed; this is called de-airing and can be accomplished either by a machine called a vacuum pug or manually by wedging. Wedging can help produce an moisture content. Once a clay body has been kneaded and de-aired or wedged, it is shaped by a variety of techniques. After it has been shaped, it is dried and fired. Greenware refers to unfired objects. At sufficient moisture content, bodies at this stage are in their most plastic form (as they are soft and mal
The Yellow River or Huang He is the second longest river in China, after the Yangtze River, the sixth longest river system in the world at the estimated length of 5,464 km. Originating in the Bayan Har Mountains in Qinghai province of Western China, it flows through nine provinces, it empties into the Bohai Sea near the city of Dongying in Shandong province; the Yellow River basin has an east–west extent of about 1,900 kilometers and a north–south extent of about 1,100 km. Its total drainage area is about 752,546 square kilometers, its basin was the birthplace of ancient Chinese civilization, it was the most prosperous region in early Chinese history. There are frequent devastating floods and course changes produced by the continual elevation of the river bed, sometimes above the level of its surrounding farm fields. Early Chinese literature including the Yu Gong or Tribute of Yu dating to the Warring States period refers to the Yellow River as 河, a character that has come to mean "river" in modern usage.
The first appearance of the name 黃河 is in the Book of Han written during the Eastern Han dynasty about the Western Han dynasty. The adjective "yellow" describes the perennial color of the muddy water in the lower course of the river, which arises from soil being carried downstream. One of its older Mongolian names was the "Black River", because the river runs clear before it enters the Loess Plateau, but the current name of the river among Inner Mongolians is Ȟatan Gol. In Mongolia itself, it is called the Šar Mörön. In Qinghai, the river's Tibetan name is "River of the Peacock" The Yellow River is one of several rivers that are essential for China's existence. At the same time, however, it has been responsible for several deadly floods, including the only natural disasters in recorded history to have killed more than a million people; the deadliest was a Yuan dynasty 1332 -- 33 flood. Close behind during the Qing dynasty is the 1887 flood, which killed anywhere from 900,000 to 2 million people, a Republic of China era 1931 flood that killed 1–4 million people.
The cause of the floods is the large amount of fine-grained loess carried by the river from the Loess Plateau, continuously deposited along the bottom of its channel. The sedimentation causes natural dams to accumulate; these subaqueous dams were unpredictable and undetectable. The enormous amount of water has to find a new way to the sea, forcing it to take the path of least resistance; when this happens, it bursts out across the flat North China Plain, sometimes taking a new channel and inundating any farmland, cities or towns in its path. The traditional Chinese response of building higher and higher levees along the banks sometimes contributed to the severity of the floods: When flood water did break through the levees, it could no longer drain back into the river bed as it would after a normal flood as the river bed was sometimes now higher than the surrounding countryside; these changes could cause the river's mouth to shift as much as 480 km, sometimes reaching the ocean to the north of Shandong Peninsula and sometimes to the south.
Another historical source of devastating floods is the collapse of upstream ice dams in Inner Mongolia with an accompanying sudden release of vast quantities of impounded water. There have been 11 such major floods in the past century, each causing tremendous loss of life and property. Nowadays, explosives dropped from aircraft are used to break the ice dams before they become dangerous. Before modern dams came to China, the Yellow River used to be prone to flooding. In the 2,540 years from 595 BC to 1946 AD, the Yellow River has been reckoned to have flooded 1,593 times, shifting its course 26 times noticeably and nine times severely; these floods include some of the deadliest natural disasters recorded. Before modern disaster management, when floods occurred, some of the population might die from drowning but many more would suffer from the ensuing famine and spread of diseases. In Chinese mythology, the giant Kua Fu drained the Yellow River and the Wei River to quench his burning thirst as he pursued the Sun.
Historical documents from the Spring and Autumn period and Qin dynasty indicate that the Yellow River at that time flowed north of its present course. These accounts show that after the river passed Luoyang, it flowed along the border between Shanxi and Henan Provinces continued along the border between Hebei and Shandong before emptying into Bohai Bay near present-day Tianjin. Another outlet followed the present course; the river left these paths in 602 BC and shifted south of the Shandong Peninsula. Sabotage of dikes and reservoirs and deliberate flooding of rival states became a standard military tactic during the Warring States period; as the Yellow River valley was the major entryway to the Guanzhong area and the state of Qin from the North China Plain, Qin fortified the Hangu Pass. Major flooding in AD 11 is credited with the downfall of the short-lived Xin dynasty, another flood in AD 70 returned the river north of Shandong on its present course. From around the beginning of the 3rd century, the importance of the Hangu Pass was reduced, with the major fortifications a
Millets are a group of variable small-seeded grasses grown around the world as cereal crops or grains for fodder and human food. Millets are important crops in the semiarid tropics of Asia and Africa, with 97% of millet production in developing countries; the crop is favored due to its productivity and short growing season under dry, high-temperature conditions. Millets are indigenous to many parts of the world; the most grown millet is pearl millet, an important crop in India and parts of Africa. Finger millet, proso millet, foxtail millet are important crop species. Millets may have been consumed by humans for about 7,000 years and had "a pivotal role in the rise of multi-crop agriculture and settled farming societies". Millets are small-grained, warm-weather cereals belonging to the grass family, they are tolerant of drought and other extreme weather conditions and have a similar nutrient content to other major cereals. The different species of millets are not closely related. All are members of the family Poaceae but can belong to different tribes or subfamilies.
The most cultivated millets are in bold and marked with an *. Eragrostideae tribe in the subfamily Chloridoideae: *Eleusine coracana: Finger millet Eragrostis tef: Teff – not considered to be a millet. Paniceae tribe in the subfamily Panicoideae: Genus Panicum: *Panicum miliaceum: Proso millet *Panicum sumatrense: Little millet *Pennisetum glaucum: Pearl millet *Setaria italica: Foxtail millet, Italian millet, panic Genus Digitaria – of minor importance as crops. Digitaria exilis: known as white fonio, fonio millet, hungry rice or acha rice. Digitaria iburua: Black fonio Digitaria compacta: Raishan, cultivated in the Khasi Hills of northeast India Digitaria sanguinalis: Polish millet Genus Echinochloa: Collectively, the members of this genus are called barnyard grasses or barnyard millets. Other common names to identify these seeds include Jhangora, Samo seeds or Morio / Mario / Moraiaya seeds. Echinochloa esculenta: Japanese barnyard millet Echinochloa frumentacea: Indian barnyard millet known as Sawa millet, Kodisama in Andhra Pradesh and Kuthirai vaali in Tamil Nadu and Bhagar or Varai in Maharashtra), Echinochloa stagnina: Burgu millet Echinochloa crus-galli: Common barnyard grass.
Paspalum scrobiculatum: Kodo millet Brachiaria deflexa: Guinea millet Urochloa ramosa: Browntop millet Andropogoneae tribe in the subfamily Panicoideae: *Sorghum bicolor: Sorghum - considered a separate cereal, but sometimes known as Great millet Coix lacryma-jobi: Job's tears known as adlay millet. Chinese legends attribute the domestication of millet to the legendary Emperor of China. Millets have been mentioned in some of the oldest extant Yajurveda texts, identifying foxtail millet, Barnyard millet and black finger millet, indicating that millet consumption was common, dating to 4500 BCE, during the Indian Bronze Age. Common millet is believed to have been the first domesticated millet dating back about 10,300 years before the present. Specialized archaeologists called palaeoethnobotanists, relying on data such as the relative abundance of charred grains found in archaeological sites, hypothesize that the cultivation of millets was of greater prevalence in prehistory than rice in northern China and Korea.
Millets formed important parts of the prehistoric diet in Indian, Chinese Neolithic and Korean Mumun societies. Broomcorn and foxtail millet were important crops beginning in the Early Neolithic of China. For example, some of the earliest evidence of millet cultivation in China was found at Cishan. Cishan dates for common millet husk phytoliths and biomolecular components have been identified around 8300–6700 BCE in storage pits along with remains of pit-houses and stone tools related to millet cultivation. Evidence at Cishan for foxtail millet dates back to around 6500 BCE. A 4,000-year-old well-preserved bowl containing well-preserved noodles made from foxtail millet and broomcorn millet was found at the Lajia archaeological site in China. Millet was growing wild in Greece as early as 3000 BCE, bulk storage containers for millet have been found from the Late Bronze Age in Macedonia and northern Greece. Hesiod describes that "the beards grow round the millet, which men sow in summer." And millet is listed along with wheat in the 3rd century BCE by Theophrastus in his "Enquiry into Plants".
Palaeoethnobotanists have found evidence of the cultivation of millet in the Korean Peninsula dating to the Middle Jeulmun pottery period. Millet continued to be an important element in the intensive, multicropping agriculture of the Mumun pottery period in Korea. Millets and their wild ancestors, such as barnyard grass and panic grass, were cultivated in Japan during the Jōmon period some time after 4000 BCE. Asian varieties of millet made their way from China to the Black Sea region of Europe by 5000 BCE; the cultivation of common millet as the earliest dry crop in East Asia has been attributed to its resistance to drought, this has been suggested to have aided its spread. Pearl millet was domesticated in the Sahel region of West Africa, where its wild ancestors are found. Evidence for the cultivation of pearl millet in Mali dates back to 2500 BCE, pearl millet is found in the Indian subcontinent by 2300 BCE. Finger millet is o
Xi'an is the capital of Shaanxi Province, China. A sub-provincial city on the Guanzhong Plain in northwestern China, it is one of the oldest cities in China, the oldest of the Four Great Ancient Capitals, having held the position under several of the most important dynasties in Chinese history, including Western Zhou, Western Han and Tang. Xi'an is the starting point of the Silk Road and home to the Terracotta Army of Emperor Qin Shi Huang. Since the 1990s, as part of the economic revival of inland China for the central and northwest regions, the city of Xi'an has re-emerged as an important cultural and educational centre of the central-northwest region, with facilities for research and development, national security and space exploration. Xi'an holds sub-provincial status, administering 9 districts and 4 counties; as of 2018 Xi'an has a population of 12,005,600, the Xi'an–Xianyang metropolitan area a population of 12.9 million. It is the most populous city in Northwest China, as well as one of the three most populous cities in Western China, the other two are Chongqing and Chengdu.
In 2012, it megalopolises, in China. "Xi'an" is the atonal pinyin romanization of the Mandarin pronunciation of its name 西安, which means "Western Peace". The name was adopted in 1369 under the early Ming dynasty. Jesuit missionaries recorded its name as "Si-ngan" or "Si-ngan-fou" from its status as the seat of a prefecture; this form still appears in the Latin name of the Catholic diocese of Xi'an, archidioecesis Singanensis. The name was romanized as "Hsi-an" by Wade & Giles and as "Sianfu" or "Sian" by the Qing imperial post office, both of which were common until the general adoption of pinyin; the area of present-day Xi'an has been the site of several important former Chinese cities. The capital of the Western Zhou were the twin cities of Feng and Hao, known collectively as Fenghao, located on opposite banks of the Feng River at its confluence with the southern bank of the Wei in the western suburbs of present-day Xi'an; the Qin capital Xianyang was erected north of the Wei during the Warring States period and was succeeded by the Western Han capital of Chang'an, meaning "Perpetual Peace", located south of the Wei and covered the central area of present-day Xi'an.
During the Eastern Han, Chang'an was known as Xijing or the "Western Capital", relative to its position to the main capital at Luoyang. Under the Sui, its name became Daxing in AD 581. Under the Tang, the name reverted to Chang'an in 618. Under the Mongolian Yuan dynasty, it held a succession of names: Fengyuan and Jingzhao; the Ming name "Xi'an" was changed back to Xijing between 1930 and 1943. Xi'an does not have a accepted one-character abbreviation as many other Chinese cities do, its license plates are marked with 陕A, based on the name of its province. Xi'an has a culturally significant history; the Lantian Man was discovered in 1963 in Lantian County, 50 km southeast of Xi'an, dates back to at least 500,000 years before the present time. A 6,500-year-old Neolithic village, was discovered in 1953 on the eastern outskirts of the city proper, which contains the remains of several well organized Neolithic settlements carbon dated to 5600–6700 years ago; the site is now home to the Xi'an Banpo Museum, built in 1957 to preserve the archaeological collection.
Xi'an became a cultural and political centre of China in the 11th century BC with the founding of the Zhou dynasty. The capital of Zhou was established in the twin settlements of Fengjing and Haojing, together known as Fenghao, located southwest of contemporary Xi'an; the settlement was known as Zhōngzhōu to indicate its role as the capital of the vassal states. In 770 BC, the capital was moved to Luoyang due to political unrest. Following the Warring States period, China was unified under the Qin dynasty for the first time, with the capital located at Xianyang, just northwest of modern Xi'an; the first emperor of China, Qin Shi Huang ordered the construction of the Terracotta Army and his mausoleum just to the east of Xi'an immediately after his ascension to the throne. In 202 BC, the founding emperor Liu Bang of the Han dynasty established his capital in Chang'an County; this is traditionally regarded as the founding date of Chang'an. Two years Liu Bang built Weiyang Palace north of modern Xi'an.
Weiyang Palace was the largest palace built on Earth, covering 4.8 square kilometres, 6.7 times the size of the current Forbidden City and 11 times the size of the Vatican City. The original Xi'an city wall took 4 years to finish. Upon completion, the wall measured 25.7 km in length and 12 to 16 m in thickness at the base, enclosing an area of 36 km2. In the year 190, amidst uprisings and rebellions just prior to the Three Kingdoms Period, a powerful warlord named Dong Zhuo moved the court from Luoyang to Chang'an in a bid to avoid a coalition of other powerful warlords against him. Following several hundred years of unrest, the Sui dynasty united China again in 582; the emperor of Sui ordered a new capital to be built southeast of the Han capital, called Daxing. It consisted of three sections: the Imperial City, the palace section, the civilian section, with a total
The Longshan culture sometimes referred to as the Black Pottery Culture, was a late Neolithic culture in the middle and lower Yellow River valley areas of northern China from about 3000 to 1900 BC. The first archaeological find of this culture took place at the Chengziya Archaeological Site in 1928, with the first excavations in 1930 and 1931; the culture is named after the nearby modern town of Longshan in Shandong. The culture was noted for its polished black pottery; the population expanded during the 3rd millennium BC, with many settlements having rammed earth walls. It decreased in most areas around 2000 BC until the central area evolved into the Bronze Age Erlitou culture. A distinctive feature of the Longshan culture was the high level of skill in pottery making, including the use of pottery wheels, producing thin-walled and polished black pottery; this pottery was widespread in North China, found in the Yangtze River valley and as far as the southeastern coast. Until the 1950s, such black pottery was considered the principal diagnostic, all of these sites were assigned to the Longshan culture.
In the first edition of his influential survey The Archaeology of Ancient China, published in 1963, Kwang-chih Chang described the whole area as a "Longshanoid horizon", suggesting a uniform culture attributed to expansion from a core area in the Central Plain. More recent discoveries have uncovered much more regional diversity than thought, so that many local cultures included within Chang's Longshanoid horizon are now viewed as distinct cultures, the term "Longshan culture" is restricted to the middle and lower Yellow River valley. For example, the contemporaneous culture of the lower Yangtze area is now described as the Liangzhu culture. At the same time, researchers recognized the diversity within the Yellow River valley by distinguishing regional variants in Henan and Shaanxi from the Shandong or "classic" Longshan. In the fourth edition of his book, Chang moved from a model centered on the Central Plain to a model of distinctive regional cultures whose development was stimulated by interaction between regions, a situation he called the "Chinese interaction sphere".
In the 1980s, Yan Wenming proposed the term "Longshan era" to encompass cultures of the late Neolithic across the area, though he assigned the Central Plain a leading role. The most important crop was foxtail millet, but traces of broomcorn millet and wheat have been found. Rice grains have been found in Shandong and southern Henan, a small rice field has been found on the Liaodong peninsula. Specialized tools for digging and grinding grain have been recovered; the most common source of meat was the pig. Sheep and goats were domesticated in the Loess Plateau area in the 4th millennium BC, found in western Henan by 2800 BC, spread across the middle and lower Yellow River area. Dogs were eaten in Shandong, though cattle were less important. Small-scale production of silk by raising and domesticating the silkworm in early sericulture was known. Remains have been found in Shaanxi and southern Henan of scapulae of cattle, pigs and deer that were heated as a form of divination. Evidence of human sacrifice becomes more common in Shaanxi and the Central Plain in the late Longshan period.
Excavations in the 1950s in Shanxian, western Henan, identified a Miaodigou II phase transitional between the preceding Yangshao culture and the Henan Longshan. A minority of archaeologists have suggested that this phase, contemporaneous with the late Dawenkou culture in Shandong, should instead be assigned to the Yangshao culture, but most describe it as the early phase of the Henan Longshan; some scholars argue that the late Dawenkou culture should be considered the early phase of the Shandong Longshan culture. Miaodigou II sites are found in central and western Henan, southern Shanxi and the Wei River valley in Shaanxi; the tools and pottery found at these sites were improved from those of the preceding Yangshao culture. Agriculture was intensified, the consumption of domesticated animals increased. Similarities in ceramic styles of central Henan Miaodigou II with the late Dawenkou culture to the east and the late Qujialing culture to the south suggest trade contacts between the regions. There were expansions from middle and late Dawenkou sites toward central Henan and northern Anhui which coincides the era of maximum marine transgression.
The late period of the Longshan culture in the middle Yellow River area is contemporaneous with the classic Shandong Longshan culture. Several regional variants of the late middle Yellow River Longshan have been identified, including Wangwan III in western Henan, Hougang II in northern Henan and southern Hebei, Taosi in the Fen River basin in southern Shanxi, several clusters on the middle reaches of the Jing River and Wei River collectively known as Kexingzhuang II or the Shaanxi Longshan; as the Neolithic population in China reached its peak, hierarchies of settlements developed. In physically circumscribed locations, such as the basin of the Fen River in southern Shanxi, the Yellow River in western Henan and the coastal Rizhao plain of southeast Shandong, a few large centers developed. In more open areas, such as the rest of Shandong, the Central Plain and the Wei River basin in Shaanxi, local centers were more numerous and evenly spaced. Walls of rammed earth have been found in 20 towns in Shandong, 9 i