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A great difference exists between a tame animal and a domesticated animal. The term "domesticated" refers to an entire species or variety while the term "tame" can refer to just one individual within a species or variety. Humans have tamed many thousands of animals that have never been truly domesticated. These include the elephant, giraffes, and bears and cats. There is debate over whether some species have been domesticated or just tamed. Some state that the elephant has been domesticated, while others argue that the cat has never been domesticated. Dividing lines include whether a specimen born to wild parents would differ in appearance or behavior from one born to domesticated parents. For instance a dog is certainly domesticated because even a wolf (which genetically shares a common ancestor with all dogs) raised from a pup would be very different from a dog, in both appearance and behaviour.[19] Similar problems of definition arise when domesticated cats go feral. Many other languages, such as Spanish, use the same word for both concepts, so such disagreements about "tamed" versus "domesticated" could not occur in those languages.[citation needed] Negative aspects Selection of animals for visible “desirable” traits may make them unfit in other, unseen, ways. The consequences for the captive and domesticated animals were reduction in size, piebald color, shorter faces with smaller and fewer teeth, diminished horns, weak muscle ridges, and less genetic variability. Poor joint definition, late fusion of the limb bone epiphyses with the diaphyses, hair changes, greater fat accumulation, smaller brains, simplified behavior patterns, extended immaturity, and more pathology are a few of the defects of domestic animals. All of these changes have been documented in direct observations of the rat in the 19th century, by archaeological evidence, and confirmed by animal breeders in the 20th century.[20] A 2014 commentary published in Genetics proposed that many of these features may arise due to mild neural crest deficits that also cause tameness; hence, selectively breeding tame animals also selects for these negative traits.[21] One side effect of domestication has been zoonotic diseases. For example, cattle have given humanity various viral poxes, measles, and tuberculosis; pigs and ducks have given influenza; and horses have given the rhinoviruses. Humans share over sixty diseases with dogs[citation needed]. Many parasites also have their origins in domestic animals.[1] The advent of domestication resulted in denser human populations which provided ripe conditions for pathogens to reproduce, mutate, spread, and eventually find a new host in humans.[citation needed] Other negative aspects of domestication have been explored. For example, Paul Shepherd writes "Man substitutes controlled breeding for natural selection; animals are selected for special traits like milk production of passivity, at the expense of overall fitness and naturewide relationships...Though domestication broadens the diversity of forms - that is, increases visible polymorphism - it undermines the crisp demarcations that separate wild species and cripples our recognition of the species as a group. Knowing only domestic animals dulls our understanding of the way in which unity and discontinuity occur as patterns in nature, and substitutes an attention to individuals and breeds. The wide variety of size, color, shape, and form of domestic horses, for example, blurs the distinction among different species of Equus that once were constant and meaningful."[22] Going further, some anarcho-primitivist authors describe domestication as the process by which previously nomadic human populations shifted towards a sedentary or settled existence through agriculture and animal husbandry. They claim that this kind of domestication demands a totalitarian relationship with both the land and the plants and animals being domesticated. They say that whereas, in a state of wildness, all life shares and competes for resources, domestication destroys this balance. Domesticated landscape (e.g. pastoral lands/agricultural fields and, to a lesser degree, horticulture and gardening) ends the open sharing of resources; where "this was everyone's," it is now "mine." Anarcho-primitivists state that this notion of ownership laid the foundation for social hierarchy as property and power emerged. It also involved the destruction, enslavement, or assimilation of other groups of early people who did not make such a transition.[23] To primitivists, domestication enslaves both the domesticated species as well as the domesticators. Advances in the fields of psychology, anthropology, and sociology allows humans to quantify and objectify themselves, until they too become commodities.[24] Dates and places Early domestication: cow being milked in ancient Egypt. Since the process of domestication inherently takes many generations over a long period of time, and the spread of breed and husbandry techniques is also slow, it is not meaningful to give a single "date of domestication". However, it is believed that the first attempt at domestication of both animals and plants were made in the Old World by peoples of the Mesolithic Period. The tribes that took part in hunting and gathering wild edible plants, started to make attempts to domesticate dogs, goats, and possibly sheep, which was as early as 9000 BC. However, it was not until the Neolithic Period that primitive agriculture appeared as a form of social activity, and domestication was well under way. The great majority of domesticated animals and plants that still serve humans were selected and developed during the Neolithic Period, a few other examples appeared later. The rabbit for example, was not domesticated until the Middle Ages, while the sugar beet came under cultivation as a sugar-yielding agricultural plant in the 19th century. As recently as the 20th century, mint became an object of agricultural production, and animal breeding programs to produce high-quality fur were started in the same time period.[25] The methods available to estimate domestication dates introduce further uncertainty, especially when domestication has occurred in the distant past. So the dates given here should be treated with caution; in some cases evidence is scanty and future discoveries may alter the dating significantly.[citation needed] Dates and places of domestication are mainly estimated by archaeological methods, more precisely archaeozoology. These methods consist of excavating or studying the results of excavation in human prehistorical occupation sites. Animal remains are dated with archaeological methods, the species they belong to is determined, the age at death is also estimated, and if possible the form they had, that is to say a possible domestic form. Various other clues are taken advantage of, such as slaughter or cutting marks. The aim is to determine if they are game or raised animal, and more globally the nature of their relationship with humans. For example the skeleton of a cat found buried close to humans is a clue that it may have been a pet cat. The age structure of animal remains can also be a clue of husbandry, in which animals were killed at the optimal age.[citation needed] New technologies and especially mitochondrial DNA, which are simple DNA found in the mitochondria that determine its function in the cell provide an alternative angle of investigation, and make it possible to reestimate the dates of domestication based on research into the genealogical tree of modern domestic animals.[citation needed] It is admitted for several species that domestication occurred in several places distinctly. For example, research on mitochondrial DNA of the modern cattle Bos taurus supports the archaeological assertions of separate domestication events in Asia and Africa. This research also shows that Bos taurus and Bos indicus haplotypes are all descendants of the extinct wild ox Bos primigenius.[26][27] However, this does not rule out later crossing inside a species; therefore it appears useless to look for a separate wild ancestor for each domestic breed. The first animal to be domesticated appears to have been the dog, in the Upper Paleolithic era. This preceded the domestication of other species by several millennia. In the Neolithic a number of important species such as the goat, sheep, pig and cow were domesticated, as part of the spread of farming which characterises this period. The goat, sheep and pig in particular were domesticated independently in the Levant and Asia.[citation needed] There is early evidence of beekeeping, in the form of rock paintings, dating to 13,000 BC.[citation needed] Recent archaeological evidence from Cyprus indicates domestication of a type of cat by perhaps 9500 BC.[28][29][30] The earliest secure evidence of horse domestication, bit wear on horse molars at Dereivka in Ukraine, dates to around 4000 BC. The unequivocal date of domestication and use as a means of transport is at the Sintashta chariot burials in the southern Urals, c. 2000 BC. Local equivalents and smaller species were domesticated from the 26th century BC.[citation needed] The availability of both domesticated vegetable and animal species increased suddenly following the voyages of Christopher Columbus and the contact between the Eastern and Western Hemispheres. This is part of what is referred to as the Columbian Exchange.[citation needed] Approximate dates and locations of original domestication Main article: List of domesticated animals Species Date Location Dog (Canis lupus familiaris) prior to 33000 BCE[31][32][33][34] Eurasia Sheep (Ovis orientalis aries) between 11000 BCE and 9000 BCE[35][36] Southwest Asia Pig (Sus scrofa domestica) 9000 BCE[37][unreliable source?][38] Near East, China, Germany Goat (Capra aegagrus hircus) 8000 BCE[39] Text document with red question mark.svg Some or all of this article's listed sources may not be reliable. Please help this article by looking for better, more reliable sources, or by checking whether the references meet the criteria for reliable sources. Unreliable citations may be challenged or deleted. (July 2014) Iran Cow (Bos primigenius taurus) 8000 BCE[40][dead link] India, Middle East, and North Africa Cat (Felis catus) 7500 BCE[28][29][30][41] Cyprus and Near East Chicken (Gallus gallus domesticus) 6000 BCE[42][dead link] India and Southeast Asia Guinea pig (Cavia porcellus) 5000 BCE[43] Peru Donkey (Equus africanus asinus) 5000 BCE[44][45] Egypt Domesticated duck (Anas platyrhynchos domesticus) 4000 BCE China Water buffalo (Bubalus bubalis) 4000 BCE India, China Horse (Equus ferus caballus) 4000 BCE[46][dead link] Eurasian Steppes Dromedary (Camelus dromedarius) 4000 BCE Arabia Llama (Lama glama) 6000 BCE Peru Silkworm (Bombyx mori) 3000 BCE China Reindeer (Rangifer tarandus) 3000 BCE[47] Russia Rock pigeon (Columba livia) 3000 BCE Mediterranean Basin Goose (Anser anser domesticus) 3000 BCE[48] Egypt Bactrian camel (Camelus bactrianus) 2500 BCE Central Asia Yak (Bos grunniens) 2500 BCE Tibet Banteng (Bos javanicus) Unknown Southeast Asia Gayal (Bos gaurus frontalis) Unknown Southeast Asia Alpaca (Vicugna pacos) 1500 BCE Peru Ferret (Mustela putorius furo) 1500 BCE Europe Muscovy Duck (Cairina momelanotus) Unknown South America Guineafowl Unknown Africa Common carp (Cyprinus carpio) Unknown East Asia Domesticated turkey (Meleagris gallopavo) 500 BCE Mexico Goldfish (Carassius auratus auratus) Unknown China European Rabbit (Oryctolagus cuniculus) CE 600 Europe Second circle[clarification needed] Species Date Location Zebu (Bos primigenius indicus) 8000 BCE India Honey bee 4000 BCE Multiple places Asian Elephant (Elephas maximus) (endangered) 2000 BCE Indus Valley civilization Fallow Deer (Dama dama) 1000 BCE Mediterranean Basin Indian Peafowl (Pavo cristatus) 500 BCE India Barbary Dove (Streptopelia risoria) 500 BCE North Africa Japanese Quail (Coturnix japonica) 1100–1900 Japan Mandarin Duck (Aix galericulata) Unknown China Mute Swan (Cygnus olor) 1000–1500 Europe Canary (Serinus canaria domestica) 1600 Canary Islands, Europe Modern instances This section possibly contains original research. Please improve it by verifying the claims made and adding inline citations. Statements consisting only of original research should be removed. (September 2007) Species Date Location Fancy rat (Rattus norvegicus) 1800s UK Fox (Vulpes vulpes) 1800s Europe European Mink (Mustela lutreola) 1800s Europe Budgerigar (Melopsittacus undulatus) 1850s Australia Cockatiel (Nymphicus hollandicus) 1870s Australia Zebra Finch (Taeniopygia guttata) 1900s Australia Hamster (Mesocricetus auratus) 1930s United States Silver Fox 1950s Soviet Union Muskox (Ovibos moschatus) 1960s United States Corn Snake (Pantherophis guttatus guttatus) 1960s United States Ball python (Python regius) 1960s Africa Madagascar hissing cockroach (Gromphadorhina portentosa) 1960s Madagascar Red Deer (Cervus elaphus) 1970s New Zealand Hedgehog (Atelerix albiventris) 1980s United States Sugar Glider (Petaurus breviceps) 1980s Australia Skunk (Mephitis mephitis) 1980s United States Capybara (Hydrochoerus hydrochaeris) 1990s United States Researchers at the Max Planck institute in Germany are attempting to find a genetic basis for the processes of taming and domestication. They have obtained two strains of grey rats which were bred by Dmitry Konstantinovich Belyaev at the Institute of Cytology and Genetics in Novosibirsk, Russia, research which was later continued by Irina Plyusnina. One strain had been selected for aggressiveness while the other had been selected for tameness, mimicking the process by which neolithic farmers are thought to have first domesticated animals. A similar experiment studying silver foxes has been ongoing at the same institute since 1959.[49] Richard Wrangham of Harvard suggests that similar genes could be involved in human self-domestication.[49] Former instances Some species are said to have been domesticated, but are not any more, either because they have totally disappeared, or since their domestic form no longer exists. Examples include the Jaguarundi,[50] the Kakapo, the Ring-tailed Cat, Caracal and Bos aegyptiacus.[citation needed] Hybrid domestic animals Alpaca: DNA evidence shows that alpacas are a llama/vicuña hybrid[citation needed] Beefalo Bengal cat Cama (animal) Chausie Coydog Dzo Domesticated Hedgehog: A cross between the Algerian Hedgehog and the Four-toed Hedgehog. Sheep-goat hybrid Hinny Huarizo Iron Age Pig Mule Savannah (cat) Wolfdog Wolphin Yakalo Zeedonk Zorse Zony Zubron Genetic pollution Main article: Genetic pollution Animals of domestic origin and feral ones sometimes can produce fertile hybrids with native, wild animals which leads to genetic pollution in the naturally evolved wild gene pools, many times threatening rare species with extinction. Cases include the mallard duck, wildcat, wild boar, the rock dove or pigeon, the Red Junglefowl (Gallus gallus) (ancestor of all chickens), carp, and more recently salmon.[citation needed] Another example is the dingo, itself an early feral dog, which hybridizes with dogs of European origin. On the other hand, genetic pollution seems not to be noticed for rabbits. There is much debate over the degree to which feral hybridization compromises the purity of a wild species. In the case of the mallard, for example, some claim there are no populations which are completely free of any domestic ancestor. |
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