A stable is a building in which livestock horses, are kept. It most means a building, divided into separate stalls for individual animals. There are many different types of stables in use today; the term "stable" is used to describe a group of animals kept by one owner, regardless of housing or location. The exterior design of a stable can vary based on climate, building materials, historical period and cultural styles of architecture. A wide range of building materials can be used, including masonry and steel. Stables range in size, from a small building housing one or two animals to facilities at agricultural shows or race tracks that can house hundreds of animals; the stable is historically the second-oldest building type on the farm. The world’s oldest horse stables were discovered in the ancient city of Pi-Ramesses in Qantir, in Ancient Egypt, were established by Ramesses II; these stables covered 182,986 square feet, had floors sloped for drainage, could contain about 480 horses. Free-standing stables began to be built from the 16th century.
They were well built and placed near the house because these animals were valued and maintained. They were once vital to an indicator of their owners' position in the community. Few examples survive of complete interiors from the mid-19th century or earlier. Traditionally, stables in Great Britain had a hayloft on their first floor and a pitching door at the front. Doors and windows were symmetrically arranged, their interiors were divided into stalls and included a large stall for a foaling mare or sick horse. The floors were featured drainage channels. Outside steps to the first floor were common for farm hands to live in the building. For horses, stables are part of a larger complex which includes trainers and farriers. "Stable" is used metaphorically to refer to a group of people – sportspeople – trained, supervised or managed by the same person or organisation. For example, art galleries refer to the artists they represent as their stable of artists; the headquarters of a unit of cavalry, not their horses' accommodation, would be known as "a stable".
Media related to stables at Wikimedia Commons. Horse care: Barns and stables Glossary of equestrian terms Livery stable Nativity of Jesus Pen
Agriculture is the science and art of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to live in cities; the history of agriculture began thousands of years ago. After gathering wild grains beginning at least 105,000 years ago, nascent farmers began to plant them around 11,500 years ago. Pigs and cattle were domesticated over 10,000 years ago. Plants were independently cultivated in at least 11 regions of the world. Industrial agriculture based on large-scale monoculture in the twentieth century came to dominate agricultural output, though about 2 billion people still depended on subsistence agriculture into the twenty-first. Modern agronomy, plant breeding, agrochemicals such as pesticides and fertilizers, technological developments have increased yields, while causing widespread ecological and environmental damage. Selective breeding and modern practices in animal husbandry have increased the output of meat, but have raised concerns about animal welfare and environmental damage.
Environmental issues include contributions to global warming, depletion of aquifers, antibiotic resistance, growth hormones in industrial meat production. Genetically modified organisms are used, although some are banned in certain countries; the major agricultural products can be broadly grouped into foods, fibers and raw materials. Food classes include cereals, fruits, meat, milk and eggs. Over one-third of the world's workers are employed in agriculture, second only to the service sector, although the number of agricultural workers in developed countries has decreased over the centuries; the word agriculture is a late Middle English adaptation of Latin agricultūra, from ager, "field", which in its turn came from Greek αγρός, cultūra, "cultivation" or "growing". While agriculture refers to human activities, certain species of ant and ambrosia beetle cultivate crops. Agriculture is defined with varying scopes, in its broadest sense using natural resources to "produce commodities which maintain life, including food, forest products, horticultural crops, their related services".
Thus defined, it includes arable farming, animal husbandry and forestry, but horticulture and forestry are in practice excluded. The development of agriculture enabled the human population to grow many times larger than could be sustained by hunting and gathering. Agriculture began independently in different parts of the globe, included a diverse range of taxa, in at least 11 separate centres of origin. Wild grains were eaten from at least 105,000 years ago. From around 11,500 years ago, the eight Neolithic founder crops and einkorn wheat, hulled barley, lentils, bitter vetch, chick peas and flax were cultivated in the Levant. Rice was domesticated in China between 11,500 and 6,200 BC with the earliest known cultivation from 5,700 BC, followed by mung and azuki beans. Sheep were domesticated in Mesopotamia between 11,000 years ago. Cattle were domesticated from the wild aurochs in the areas of modern Turkey and Pakistan some 10,500 years ago. Pig production emerged in Eurasia, including Europe, East Asia and Southwest Asia, where wild boar were first domesticated about 10,500 years ago.
In the Andes of South America, the potato was domesticated between 10,000 and 7,000 years ago, along with beans, llamas and guinea pigs. Sugarcane and some root vegetables were domesticated in New Guinea around 9,000 years ago. Sorghum was domesticated in the Sahel region of Africa by 7,000 years ago. Cotton was domesticated in Peru by 5,600 years ago, was independently domesticated in Eurasia. In Mesoamerica, wild teosinte was bred into maize by 6,000 years ago. Scholars have offered multiple hypotheses to explain the historical origins of agriculture. Studies of the transition from hunter-gatherer to agricultural societies indicate an initial period of intensification and increasing sedentism. Wild stands, harvested started to be planted, came to be domesticated. In Eurasia, the Sumerians started to live in villages from about 8,000 BC, relying on the Tigris and Euphrates rivers and a canal system for irrigation. Ploughs appear in pictographs around 3,000 BC. Farmers grew wheat, vegetables such as lentils and onions, fruits including dates and figs.
Ancient Egyptian agriculture relied on its seasonal flooding. Farming started in the predynastic period at the end of the Paleolithic, after 10,000 BC. Staple food crops were grains such as wheat and barley, alongside industrial crops such as flax and papyrus. In India, wheat and jujube were domesticated by 9,000 BC, soon followed by sheep and goats. Cattle and goats were domesticated in Mehrgarh culture by 8,000–6,000 BC. Cotton was cultivated by the 5th-4th millennium BC. Archeological evidence indicates an animal-drawn plough from 2,500 BC in the Indus Valley Civilisation. In China, from the 5th century BC there was a nationwide granary system and widespread silk farming. Water-powered grain mills were in use followed by irrigation. By the late 2nd century, heavy ploughs had been developed with iron mouldboards; these spread westwards across Eurasia. Asian rice was domesticated 8,200–13,500 years ago – depending on the molecular clock estimate, used – on the Pearl River in southern China with a single genetic origin from the wild rice Oryza rufipogon
Rabbits are small mammals in the family Leporidae of the order Lagomorpha. Oryctolagus cuniculus includes the European rabbit species and its descendants, the world's 305 breeds of domestic rabbit. Sylvilagus includes 13 wild rabbit species, among them the 7 types of cottontail; the European rabbit, introduced on every continent except Antarctica, is familiar throughout the world as a wild prey animal and as a domesticated form of livestock and pet. With its widespread effect on ecologies and cultures, the rabbit is, in many areas of the world, a part of daily life—as food, clothing, a companion, as a source of artistic inspiration. Male rabbits are called bucks. An older term for an adult rabbit is coney. Another term for a young rabbit is bunny, though this term is applied informally to rabbits especially domestic ones. More the term kit or kitten has been used to refer to a young rabbit. A group of rabbits is known as a nest. A group of baby rabbits produced from a single mating is referred to as a litter, a group of domestic rabbits living together is sometimes called a herd.
Rabbits and hares were classified in the order Rodentia until 1912, when they were moved into a new order, Lagomorpha. Below are some of the species of the rabbit. Order Lagomorpha Family Leporidae Hares are precocial, born mature and mobile with hair and good vision, while rabbits are altricial, born hairless and blind, requiring closer care. Hares live a solitary life in a simple nest above the ground, while most rabbits live in social groups underground in burrows or warrens. Hares are larger than rabbits, with ears that are more elongated, with hind legs that are larger and longer. Hares have not been domesticated, while descendants of the European rabbit are bred as livestock and kept as pets. Rabbits have long been domesticated. Beginning in the Middle Ages, the European rabbit has been kept as livestock, starting in ancient Rome. Selective breeding has generated a wide variety of rabbit breeds, many of which are kept as pets; some strains of rabbit have been bred as research subjects. As livestock, rabbits are bred for their fur.
The earliest breeds were important sources of meat, so became larger than wild rabbits, but domestic rabbits in modern times range in size from dwarf to giant. Rabbit fur, prized for its softness, can be found in a broad range of coat colors and patterns, as well as lengths; the Angora rabbit breed, for example, was developed for its long, silky fur, hand-spun into yarn. Other domestic rabbit breeds have been developed for the commercial fur trade, including the Rex, which has a short plush coat; because the rabbit's epiglottis is engaged over the soft palate except when swallowing, the rabbit is an obligate nasal breather. Rabbits have two sets of one behind the other; this way they can be distinguished from rodents, with which they are confused. Carl Linnaeus grouped rabbits and rodents under the class Glires. However, recent DNA analysis and the discovery of a common ancestor has supported the view that they do share a common lineage, thus rabbits and rodents are now referred to together as members of the superorder Glires.
Since speed and agility are a rabbit's main defenses against predators, rabbits have large hind leg bones and well developed musculature. Though plantigrade at rest, rabbits are on their toes while running, assuming a more digitigrade form. Rabbits use their strong claws for defense; each front foot has four toes plus a dewclaw. Each hind foot has four toes. Most wild rabbits have full, egg-shaped bodies; the soft coat of the wild rabbit is agouti in coloration. The tail of the rabbit is dark on white below. Cottontails have white on the top of their tails; as a result of the position of the eyes in its skull, the rabbit has a field of vision that encompasses nearly 360 degrees, with just a small blind spot at the bridge of the nose. The anatomy of rabbits' hind limbs are structurally similar to that of other land mammals and contribute to their specialized form of locomotion; the Bones of the hind limbs consist of long bones as well as short bones. These bones are created through endochondral ossification during development.
Like most land mammals, the round head of the femur articulates with the acetabulum of the ox coxae. The femur articulates with the tibia, but not the fibula, fused to the tibia; the tibia and fibula articulate with the tarsals of the pes called the foot. The hind limbs of the rabbit are longer than the front limbs; this allows them to produce their hopping form of locomotion. Longer hind limbs are more capable of producing faster speeds. Hares, which have longer legs than cottontail rabbits, are able to move faster. Rabbits stay just on their toes; the hind feet have four long toes that allow for this and are webbed to prevent them from spreading when hopping. Rabbits do not have paw
Blood is a body fluid in humans and other animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells. In vertebrates, it is composed of blood cells suspended in blood plasma. Plasma, which constitutes 55% of blood fluid, is water, contains proteins, mineral ions, carbon dioxide, blood cells themselves. Albumin is the main protein in plasma, it functions to regulate the colloidal osmotic pressure of blood; the blood cells are red blood cells, white blood cells and platelets. The most abundant cells in vertebrate blood are red blood cells; these contain hemoglobin, an iron-containing protein, which facilitates oxygen transport by reversibly binding to this respiratory gas and increasing its solubility in blood. In contrast, carbon dioxide is transported extracellularly as bicarbonate ion transported in plasma. Vertebrate blood is bright red when its hemoglobin is oxygenated and dark red when it is deoxygenated.
Some animals, such as crustaceans and mollusks, use hemocyanin to carry oxygen, instead of hemoglobin. Insects and some mollusks use a fluid called hemolymph instead of blood, the difference being that hemolymph is not contained in a closed circulatory system. In most insects, this "blood" does not contain oxygen-carrying molecules such as hemoglobin because their bodies are small enough for their tracheal system to suffice for supplying oxygen. Jawed vertebrates have an adaptive immune system, based on white blood cells. White blood cells help to resist parasites. Platelets are important in the clotting of blood. Arthropods, using hemolymph, have hemocytes as part of their immune system. Blood is circulated around the body through blood vessels by the pumping action of the heart. In animals with lungs, arterial blood carries oxygen from inhaled air to the tissues of the body, venous blood carries carbon dioxide, a waste product of metabolism produced by cells, from the tissues to the lungs to be exhaled.
Medical terms related to blood begin with hemo- or hemato- from the Greek word αἷμα for "blood". In terms of anatomy and histology, blood is considered a specialized form of connective tissue, given its origin in the bones and the presence of potential molecular fibers in the form of fibrinogen. Blood performs many important functions within the body, including: Supply of oxygen to tissues Supply of nutrients such as glucose, amino acids, fatty acids Removal of waste such as carbon dioxide and lactic acid Immunological functions, including circulation of white blood cells, detection of foreign material by antibodies Coagulation, the response to a broken blood vessel, the conversion of blood from a liquid to a semisolid gel to stop bleeding Messenger functions, including the transport of hormones and the signaling of tissue damage Regulation of core body temperature Hydraulic functions Blood accounts for 7% of the human body weight, with an average density around 1060 kg/m3 close to pure water's density of 1000 kg/m3.
The average adult has a blood volume of 5 litres, composed of plasma and several kinds of cells. These blood cells consist of erythrocytes and thrombocytes. By volume, the red blood cells constitute about 45% of whole blood, the plasma about 54.3%, white cells about 0.7%. Whole blood exhibits non-Newtonian fluid dynamics. If all human hemoglobin were free in the plasma rather than being contained in RBCs, the circulatory fluid would be too viscous for the cardiovascular system to function effectively. One microliter of blood contains: 4.7 to 6.1 million, 4.2 to 5.4 million erythrocytes: Red blood cells contain the blood's hemoglobin and distribute oxygen. Mature red blood cells lack a nucleus and organelles in mammals; the red blood cells are marked by glycoproteins that define the different blood types. The proportion of blood occupied by red blood cells is referred to as the hematocrit, is about 45%; the combined surface area of all red blood cells of the human body would be 2,000 times as great as the body's exterior surface.
4,000–11,000 leukocytes: White blood cells are part of the body's immune system. The cancer of leukocytes is called leukemia. 200,000 -- 500,000 thrombocytes: Also called platelets. Fibrin from the coagulation cascade creates a mesh over the platelet plug. About 55% of blood is blood plasma, a fluid, the blood's liquid medium, which by itself is straw-yellow in color; the blood plasma volume totals of 2.7–3.0 liters in an average human. It is an aqueous solution containing 92% water, 8% blood plasma proteins, trace amounts of other materials. Plasma circulates dissolved nutrients, such as glucose, amino acids, fatty acids, removes waste products, such as carbon dioxide and lactic acid. Other important components include: Serum albumin Blood-clotting factors Immunoglobulins lipoprotein particles Various
Beer is one of the oldest and most consumed alcoholic drinks in the world, the third most popular drink overall after water and tea. Beer is brewed from cereal grains—most from malted barley, though wheat and rice are used. During the brewing process, fermentation of the starch sugars in the wort produces ethanol and carbonation in the resulting beer. Most modern beer is brewed with hops, which add bitterness and other flavours and act as a natural preservative and stabilizing agent. Other flavouring agents such as gruit, herbs, or fruits may be used instead of hops. In commercial brewing, the natural carbonation effect is removed during processing and replaced with forced carbonation; some of humanity's earliest known writings refer to the production and distribution of beer: the Code of Hammurabi included laws regulating beer and beer parlours, "The Hymn to Ninkasi", a prayer to the Mesopotamian goddess of beer, served as both a prayer and as a method of remembering the recipe for beer in a culture with few literate people.
Beer is distributed in bottles and cans and is commonly available on draught in pubs and bars. The brewing industry is a global business, consisting of several dominant multinational companies and many thousands of smaller producers ranging from brewpubs to regional breweries; the strength of modern beer is around 4% to 6% alcohol by volume, although it may vary between 0.5% and 20%, with some breweries creating examples of 40% ABV and above. Beer forms part of the culture of many nations and is associated with social traditions such as beer festivals, as well as a rich pub culture involving activities like pub crawling and pub games. Beer is one of the world's oldest prepared drinks; the earliest archaeological evidence of fermentation consists of 13,000 year old residues of a beer with the consistency of gruel, used by the semi-nomadic Natufians for ritual feasting, at the Raqefet Cave in the Carmel Mountains near Haifa in Israel. There is evidence; the earliest clear chemical evidence of beer produced from barley dates to about 3500–3100 BC, from the site of Godin Tepe in the Zagros Mountains of western Iran.
It is possible, but not proven, that it dates back further — to about 10,000 BC, when cereal was first farmed. Beer is recorded in the written history of ancient Iraq and ancient Egypt, archaeologists speculate that beer was instrumental in the formation of civilizations. 5000 years ago, workers in the city of Uruk were paid by their employers in beer. During the building of the Great Pyramids in Giza, each worker got a daily ration of four to five litres of beer, which served as both nutrition and refreshment, crucial to the pyramids' construction; some of the earliest Sumerian writings contain references to beer. The Ebla tablets, discovered in 1974 in Ebla, show that beer was produced in the city in 2500 BC. A fermented drink using rice and fruit was made in China around 7000 BC. Unlike sake, mold was not used to saccharify the rice. Any substance containing sugar can undergo alcoholic fermentation, it is that many cultures, on observing that a sweet liquid could be obtained from a source of starch, independently invented beer.
Bread and beer increased prosperity to a level that allowed time for development of other technologies and contributed to the building of civilizations. Xenophon noted. Beer was spread through Europe by Germanic and Celtic tribes as far back as 3000 BC, it was brewed on a domestic scale; the product that the early Europeans drank might not be recognised as beer by most people today. Alongside the basic starch source, the early European beers might contain fruits, numerous types of plants and other substances such as narcotic herbs. What they did not contain was hops, as, a addition, first mentioned in Europe around 822 by a Carolingian Abbot and again in 1067 by abbess Hildegard of Bingen. In 1516, William IV, Duke of Bavaria, adopted the Reinheitsgebot the oldest food-quality regulation still in use in the 21st century, according to which the only allowed ingredients of beer are water and barley-malt. Beer produced before the Industrial Revolution continued to be made and sold on a domestic scale, although by the 7th century AD, beer was being produced and sold by European monasteries.
During the Industrial Revolution, the production of beer moved from artisanal manufacture to industrial manufacture, domestic manufacture ceased to be significant by the end of the 19th century. The development of hydrometers and thermometers changed brewing by allowing the brewer more control of the process and greater knowledge of the results. In 1912, the use of brown bottles began to be used by Joseph Schlitz Brewing Company of Milwaukee, Wisconsin in the United States; this innovation has since been accepted worldwide and prevents harmful rays from destroying the quality and stability of beer. As of 2007, the brewing industry is a global business, consisting of several dominant multinational companies and many thousands of smaller producers ran
Domestic sheep are quadrupedal, ruminant mammals kept as livestock. Like most ruminants, sheep are members of the even-toed ungulates. Although the name sheep applies to many species in the genus Ovis, in everyday usage it always refers to Ovis aries. Numbering a little over one billion, domestic sheep are the most numerous species of sheep. An adult female sheep is referred to as a ewe, an intact male as a ram or a tup, a castrated male as a wether, a younger sheep as a lamb. Sheep are most descended from the wild mouflon of Europe and Asia. One of the earliest animals to be domesticated for agricultural purposes, sheep are raised for fleeces and milk. A sheep's wool is the most used animal fiber, is harvested by shearing. Ovine meat is called lamb when from younger animals and mutton when from older ones in Commonwealth countries, lamb in the United States. Sheep continue to be important for wool and meat today, are occasionally raised for pelts, as dairy animals, or as model organisms for science.
Sheep husbandry is practised throughout the majority of the inhabited world, has been fundamental to many civilizations. In the modern era, New Zealand, the southern and central South American nations, the British Isles are most associated with sheep production. Sheepraising has a large lexicon of unique terms which vary by region and dialect. Use of the word sheep began in Middle English as a derivation of the Old English word scēap. A group of sheep is called a herd or mob. Many other specific terms for the various life stages of sheep exist related to lambing and age. Being a key animal in the history of farming, sheep have a entrenched place in human culture, find representation in much modern language and symbology; as livestock, sheep are most associated with pastoral, Arcadian imagery. Sheep figure in many mythologies—such as the Golden Fleece—and major religions the Abrahamic traditions. In both ancient and modern religious ritual, sheep are used as sacrificial animals; the exact line of descent between domestic sheep and their wild ancestors is unclear.
The most common hypothesis states. Sheep were among the first animals to be domesticated by humankind. C in Mesopotamia; the rearing of sheep for secondary products, the resulting breed development, began in either southwest Asia or western Europe. Sheep were kept for meat and skins. Archaeological evidence from statuary found at sites in Iran suggests that selection for woolly sheep may have begun around 6000 BC, the earliest woven wool garments have been dated to two to three thousand years later. Sheep husbandry spread in Europe. Excavations show that in about 6000 BC, during the Neolithic period of prehistory, the Castelnovien people, living around Châteauneuf-les-Martigues near present-day Marseille in the south of France, were among the first in Europe to keep domestic sheep. From its inception, ancient Greek civilization relied on sheep as primary livestock, were said to name individual animals. Ancient Romans kept sheep on a wide scale, were an important agent in the spread of sheep raising.
Pliny the Elder, in his Natural History, speaks at length about wool. European colonists spread the practice to the New World from 1493 onwards. Domestic sheep are small ruminants with a crimped hair called wool and with horns forming a lateral spiral. Domestic sheep differ from their wild relatives and ancestors in several respects, having become uniquely neotenic as a result of selective breeding by humans. A few primitive breeds of sheep retain some of the characteristics of their wild cousins, such as short tails. Depending on breed, domestic sheep may have no horns at all, or horns in both sexes, or in males only. Most horned breeds have a single pair. Another trait unique to domestic sheep as compared to wild ovines is their wide variation in color. Wild sheep are variations of brown hues, variation within species is limited. Colors of domestic sheep range from pure white to dark chocolate brown, spotted or piebald. Selection for dyeable white fleeces began early in sheep domestication, as white wool is a dominant trait it spread quickly.
However, colored sheep do appear in many modern breeds, may appear as a recessive trait in white flocks. While white wool is desirable for large commercial markets, there is a niche market for colored fleeces for handspinning; the nature of the fleece varies among the breeds, from dense and crimped, to long and hairlike. There is variation of wool type and quality among members of the same flock, so wool classing is a step in the commercial processing of the fibre. Depending on breed, sheep show a range of weights, their rate of growth and mature weight is a heritable trait, selected for in breeding. Ewes weigh between 45 and 100 kilograms, rams between 45 and 160 kilograms; when all deciduous teeth have erupted, the sheep has 20 teeth. Mature sheep have 32 teeth; as with other ruminants, the front teeth in the lower jaw bite against a hard, toothless pad in the upper jaw. These are used to pick off vegetation the rear
The chicken is a type of domesticated fowl, a subspecies of the red junglefowl. It is one of the most common and widespread domestic animals, with a total population of more than 19 billion as of 2011. There are more chickens in the world than domesticated fowl. Humans keep chickens as a source of food and, less as pets. Raised for cockfighting or for special ceremonies, chickens were not kept for food until the Hellenistic period. Genetic studies have pointed to multiple maternal origins in South Asia, Southeast Asia, East Asia, but with the clade found in the Americas, the Middle East and Africa originating in the Indian subcontinent. From ancient India, the domesticated chicken spread to Lydia in western Asia Minor, to Greece by the 5th century BC. Fowl had been known in Egypt since the mid-15th century BC, with the "bird that gives birth every day" having come to Egypt from the land between Syria and Shinar, according to the annals of Thutmose III; the chicken used for regular egg and meat production worldwide are corn-ply Broilers with white feathers, yellowish skin and faster growth rate invented in United States of America In the UK and Ireland, adult male chickens over the age of one year are known as cocks, whereas in the United States, Canada and New Zealand, they are more called roosters.
Males less than a year old are cockerels. Castrated roosters are called capons. Females over a year old are known as hens, younger females as pullets, although in the egg-laying industry, a pullet becomes a hen when she begins to lay eggs, at 16 to 20 weeks of age. In Australia and New Zealand, there is a generic term chook to describe all both sexes; the young are called chicks. "Chicken" referred to young domestic fowl. The species as a whole was called domestic fowl, or just fowl; this use of "chicken" survives in the phrase "Hen and Chickens", sometimes used as a British public house or theatre name, to name groups of one large and many small rocks or islands in the sea. The word "chicken" is sometimes erroneously construed to mean females despite the term "hen" for females being in wide circulation, the term “rooster” for males being that most used. In the Deep South of the United States, chickens are referred to by the slang term yardbird. Chickens are omnivores. In the wild, they scratch at the soil to search for seeds and animals as large as lizards, small snakes, or young mice.
The average chicken may live depending on the breed. The world's oldest known chicken was a hen which died of heart failure at the age of 16 years according to the Guinness World Records. Roosters can be differentiated from hens by their striking plumage of long flowing tails and shiny, pointed feathers on their necks and backs, which are of brighter, bolder colours than those of females of the same breed. However, in some breeds, such as the Sebright chicken, the rooster has only pointed neck feathers, the same colour as the hen's; the identification can be made by looking at the comb, or from the development of spurs on the male's legs. Adult chickens have a fleshy crest on their heads called a comb, or cockscomb, hanging flaps of skin either side under their beaks called wattles. Collectively and other fleshy protuberances on the head and throat are called caruncles. Both the adult male and female have wattles and combs, but in most breeds these are more prominent in males. A muff or beard is a mutation found in several chicken breeds which causes extra feathering under the chicken's face, giving the appearance of a beard.
Domestic chickens are not capable of long distance flight, although lighter birds are capable of flying for short distances, such as over fences or into trees. Chickens may fly to explore their surroundings, but do so only to flee perceived danger. Chickens live together in flocks, they have a communal approach to the incubation of eggs and raising of young. Individual chickens in a flock will dominate others, establishing a "pecking order", with dominant individuals having priority for food access and nesting locations. Removing hens or roosters from a flock causes a temporary disruption to this social order until a new pecking order is established. Adding hens younger birds, to an existing flock can lead to fighting and injury; when a rooster finds food, he may call other chickens to eat first. He does this by clucking in a high pitch as well as dropping the food; this behaviour may be observed in mother hens to call their chicks and encourage them to eat. A rooster's crowing is a loud and sometimes shrill call and sends a territorial signal to other roosters.
However, roosters may crow in response to sudden disturbances within their surroundings. Hens cluck loudly after laying an egg, to call their chicks. Chickens give different warning calls when they sense a predator approaching from the air or on the ground. To initiate courting, some roosters may dance in a circle around or near a hen lowering the wing, closest to the hen; the dance triggers a response in the hen and when she responds to his "call", the rooster may mount the hen and proceed with the mating. More matin