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Origin of the domestic dog. from post-domestication wolf–dog hybridization in subclade d1 (Scandinavia) and d2 (South-West Asia). The northern Scandinavian subclade d1 hybrid haplotypes originated 480-3,000 YBP and are found in all Sami-related breeds: Finnish Lapphund, Swedish Lapphund, Lapponian Herder, Jamthund, Norwegian Elkhound and Hällefors Elkhound. The maternal wolf sequence that contributed to them has not been matched across Eurasia and its branch is phylogenetically rooted in the same sequence as the Altai dog (not a direct ancestor). The subclade d2 hybrid haplotypes are found in 2.6% of South-West Asian dogs. Haplogroup E: Derived from post-domestication wolf–dog hybridization in East Asia, (rare distribution in South-East
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Origin of the domestic dog. Asia, Korea and Japan). Haplogroup F: Derived from post-domestication wolf–dog hybridization in Japan. A study of 600 dog specimens found only one dog whose sequence indicated hybridization with the extinct Japanese wolf. It is not known whether this hybridization was the result of humans selecting for phenotypic traits from local wolf populations or the result of natural introgression as the dog expanded across Eurasia. In 2018, a study found a small amount of dog ancestry in 62% of Eurasian wolf specimens looked at, that hybridization had occurred across a wide number of timescales and not just recently, however in contrast
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Origin of the domestic dog. there was almost no admixture detected in the North American specimens. There was introgression of the male dog into the wolf, but also one hybrid detected which was the result of a male wolf crossed with a female dog. Wolves have maintained their phenotype differences from the dog, which indicates low-frequency hybridization. The conclusion is that phenotype is no indication of "purity" and the definition of pure wolves is ambiguous. Free-ranging dogs across Eurasia show introgression from wolves. Another study found that the β-defensin gene responsible for the black coat of North American wolves was the result of a single
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Origin of the domestic dog. introgression from dogs in the Yukon dated between 1,600-7,200 years ago. The study proposes that early Native American dogs were the source. Section:Dog domestication.:Post-domestication gene flow.:Taimyr wolf admixture. In May 2015, a study compared the ancestry of the Taimyr-1 wolf lineage to that of dogs and gray wolves. Comparison to the gray wolf lineage indicated that Taimyr-1 was basal to gray wolves from the Middle East, China, Europe and North America but shared a substantial amount of history with the present-day gray wolves after their divergence from the coyote. This implies that the ancestry of the majority of gray wolf
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Origin of the domestic dog. populations today stems from an ancestral population that lived less than 35,000 years ago but before the inundation of the Bering Land Bridge with the subsequent isolation of Eurasian and North American wolves. A comparison of the ancestry of the Taimyr-1 lineage to the dog lineage indicated that some modern dog breeds have a closer association with either the gray wolf or Taimyr-1 due to admixture. The Saarloos wolfdog showed more association with the gray wolf, which is in agreement with the documented historical crossbreeding with gray wolves in this breed. Taimyr-1 shared more alleles (i.e. gene expressions) with those
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Origin of the domestic dog. breeds that are associated with high latitudes - the Siberian husky and Greenland dog that are also associated with arctic human populations, and to a lesser extent the Shar Pei and Finnish spitz. An admixture graph of the Greenland dog indicates a best-fit of 3.5% shared material, although an ancestry proportion ranging between 1.4% and 27.3% is consistent with the data. This indicates admixture between the Taimyr-1 population and the ancestral dog population of these four high-latitude breeds. These results can be explained either by a very early presence of dogs in northern Eurasia or by the genetic legacy of
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Origin of the domestic dog. Taimyr-1 being preserved in northern wolf populations until the arrival of dogs at high latitudes. This introgression could have provided early dogs living in high latitudes with phenotypic variation beneficial for adaption to a new and challenging environment. It also indicates that the ancestry of present-day dog breeds descends from more than one region. An attempt to explore admixture between Taimyr-1 and gray wolves produced unreliable results. As the Taimyr wolf had contributed to the genetic makeup of the Arctic breeds, a later study suggested that descendants of the Taimyr wolf survived until dogs were domesticated in Europe and arrived
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Origin of the domestic dog. at high latitudes where they mixed with local wolves, and these both contributed to the modern Arctic breeds. Based on the most widely accepted oldest zooarchaeological dog remains, domestic dogs most likely arrived at high latitudes within the last 15,000 years. The mutation rates calibrated from both the Taimyr wolf and the Newgrange dog genomes suggest that modern wolf and dog populations diverged from a common ancestor between 20,000 and 60,000 YBP. This indicates that either dogs were domesticated much earlier than their first appearance in the archaeological record, or they arrived in the Arctic early, or both. Section:Dog domestication.:Positive
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Origin of the domestic dog. selection. Charles Darwin recognized the small number of traits that made domestic species different from their wild ancestors. He was also the first to recognize the difference between conscious selective breeding in which humans directly select for desirable traits, and unconscious selection where traits evolve as a by-product of natural selection or from selection on other traits. Domestic animals have variations in coat color as well as texture, dwarf and giant varieties, and changes in their reproductive cycle, and many others have tooth crowding and floppy ears. Although it is easy to assume that each of these traits was uniquely
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Origin of the domestic dog. selected for by hunter-gatherers and early farmers, beginning in 1959 Dmitry Belyayev tested the reactions of silver foxes to a hand placed in their cage and selected the tamest, least aggressive individuals to breed. His hypothesis was that, by selecting a behavioral trait, he could also influence the phenotype of subsequent generations, making them more domestic in appearance. Over the next 40 years, he succeeded in producing foxes with traits that were never directly selected for, including piebald coats floppy ears, upturned tails, shortened snouts, and shifts in developmental timing. In the 1980s, a researcher used a set of behavioral,
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Origin of the domestic dog. cognitive, and visible phenotypic markers, such as coat colour, to produce domesticated fallow deer within a few generations. Similar results for tameness and fear have been found for mink and Japanese quail. In addition to demonstrating that domestic phenotypic traits could arise through selection for a behavioral trait, and domestic behavioral traits could arise through the selection for a phenotypic trait, these experiments provided a mechanism to explain how the animal domestication process could have begun without deliberate human forethought and action. The genetic difference between domestic and wild populations can be framed within two considerations. The first distinguishes between
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Origin of the domestic dog. domestication traits that are presumed to have been essential at the early stages of domestication, and improvement traits that have appeared since the split between wild and domestic populations. Domestication traits are generally fixed within all domesticates and were selected during the initial episode of domestication, whereas improvement traits are present only in a proportion of domesticates, though they may be fixed in individual breeds or regional populations. A second issue is whether traits associated with the domestication syndrome resulted from a relaxation of selection as animals exited the wild environment or from positive selection resulting from intentional and unintentional
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Origin of the domestic dog. human preference. Some recent genomic studies on the genetic basis of traits associated with the domestication syndrome have shed light on both of these issues. A study published in 2016 suggested that there have been negative genetic consequences of the domestication process as well, that enrichment of disease-related gene variants accompanied positively selected traits. In 2010, a study identified 51 regions of the dog genome that were associated with phenotypic variation among breeds in 57 traits studied, which included body, cranial, dental, and long bone shape and size. There were 3 quantitative trait loci that explained most of the phenotypic
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Origin of the domestic dog. variation. Indicators of recent selection were shown by many of the 51 genomic regions that were associated with traits that define a breed, which include body size, coat characteristics, and ear floppiness. Geneticists have identified more than 300 genetic loci and 150 genes associated with coat color variability. Knowing the mutations associated with different colors has allowed the correlation between the timing of the appearance of variable coat colors in horses with the timing of their domestication. Other studies have shown how human-induced selection is responsible for the allelic variation in pigs. Together, these insights suggest that, although natural selection
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Origin of the domestic dog. has kept variation to a minimum before domestication, humans have actively selected for novel coat colors as soon as they appeared in managed populations. In 2015, a study looked at over 100 pig genome sequences to ascertain their process of domestication. A model that fitted the data included admixture with a now extinct ghost population of wild pigs during the Pleistocene. The study also found that despite back-crossing with wild pigs, the genomes of domestic pigs have strong signatures of selection at genetic loci that affect behavior and morphology. The study concluded that human selection for domestic traits likely counteracted
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Origin of the domestic dog. the homogenizing effect of gene flow from wild boars and created domestication islands in the genome. The same process may also apply to other domesticated animals. In 2014, a whole genome study of the DNA differences between wolves and dogs found that dogs did not show a reduced fear response but did show greater synaptic plasticity. Synaptic plasticity is widely believed to be the cellular correlate of learning and memory, and this change may have altered the learning and memory abilities of dogs in comparison to wolves. Section:Dog domestication.:Positive selection.:Behavior. Unlike other domestic species which were primarily selected for production-related
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Origin of the domestic dog. traits, dogs were initially selected for their behaviors. In 2016, a study found that there were only 11 fixed genes that showed variation between wolves and dogs. These gene variations were unlikely to have been the result of natural evolution, and indicate selection on both morphology and behavior during dog domestication. There was evidence of selection during dog domestication of genes that affect the adrenaline and noradrenaline biosynthesis pathway. These genes are involved in the synthesis, transport and degradation of a variety of neurotransmitters, particularly the catecholamines, which include dopamine and noradrenaline. Recurrent selection on this pathway and its role
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Origin of the domestic dog. in emotional processing and the fight-or-flight response suggests that the behavioral changes we see in dogs compared to wolves may be due to changes in this pathway, leading to tameness and an emotional processing ability. Dogs generally show reduced fear and aggression compared to wolves. Some of these genes have been associated with aggression in some dog breeds, indicating their importance in both the initial domestication and then later in breed formation. In 2018, a study identified 429 genes that differed between modern dogs and modern wolves. As the differences in these genes could also be found in ancient dog
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Origin of the domestic dog. fossils, these were regarded as being the result of the initial domestication and not from recent breed formation. These genes are linked to neural crest and central nervous system development. These genes affect embryogenesis and can confer tameness, smaller jaws, floppy ears, and diminished craniofacial development, which distinguish domesticated dogs from wolves and are considered to reflect domestication syndrome. The study proposes that domestication syndrome is caused by alterations in the migration or activity of neural crest cells during their development. The study concluded that during early dog domestication, the initial selection was for behavior. This trait is influenced by
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Origin of the domestic dog. those genes which act in the neural crest, which led to the phenotypes observed in modern dogs. Section:Dog domestication.:Positive selection.:Dietary adaption. AMY2B (Alpha-Amylase 2B) is a gene that codes a protein that assists with the first step in the digestion of dietary starch and glycogen. An expansion of this gene in dogs would enable early dogs to exploit a starch-rich diet as they fed on refuse from agriculture. In a study in 2014, the data indicated that the wolves and dingo had just two copies of the gene and the Siberian Husky that is associated with hunter-gatherers had just three
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Origin of the domestic dog. or four copies, whereas the Saluki that is associated with the Fertile Crescent where agriculture originated had 29 copies. The results show that on average, modern dogs have a high copy number of the gene, whereas wolves and dingoes do not. The high copy number of AMY2B variants likely already existed as a standing variation in early domestic dogs, but expanded more recently with the development of large agriculturally based civilizations. This suggests that at the beginning of the domestication process, dogs may have been characterized by a more carnivorous diet than their modern-day counterparts, a diet held in common
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Origin of the domestic dog. with early hunter-gatherers. A later study indicated that because most dogs had a high copy number of the AMY2B gene but the arctic breeds and the dingo did not, that the dog's dietary change may not have been caused by initial domestication but by the subsequent spread of agriculture to most - but not all - regions of the planet. In 2016, a study of the dog genome compared to the wolf genome looked for genes that showed signs of having undergone positive selection. The study identified genes relating to brain function and behavior, and to lipid metabolism. This ability
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Origin of the domestic dog. to process lipids indicates a dietary target of selection that was important when proto-dogs hunted and fed alongside hunter-gatherers. The evolution of the dietary metabolism genes may have helped process the increased lipid content of early dog diets as they scavenged on the remains of carcasses left by hunter-gatherers. Prey capture rates may have increased in comparison to wolves and with it the amount of lipid consumed by the assisting proto-dogs. A unique dietary selection pressure may have evolved both from the amount consumed, and the shifting composition of, tissues that were available to proto-dogs once humans had removed the
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Origin of the domestic dog. most desirable parts of the carcass for themselves. A study of the mammal biomass during modern human expansion into the northern Mammoth steppe found that it had occurred under conditions of unlimited resources, and that many of the animals were killed with only a small part consumed or left unused. Section:Dog domestication.:Natural selection. Dogs can infer the name of an object and have been shown to learn the names of over 1,000 objects. Dogs can follow the human pointing gesture; even nine-week-old puppies can follow a basic human pointing gesture without being taught. New Guinea singing dogs, a half-wild proto-dog
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Origin of the domestic dog. endemic to the remote alpine regions of New Guinea, as well as dingoes in the remote Outback of Australia are also capable of this. These examples demonstrate an ability to read human gestures that arose early in domestication and did not require human selection. "Humans did not develop dogs, we only fine-tuned them down the road." A dog's cranium is 15% smaller than an equally heavy wolf's, and the dog is less aggressive and more playful. Other species pairs show similar differences. Bonobos, like chimpanzees, are a close genetic cousin to humans, but unlike the chimpanzees, bonobos are not aggressive
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Origin of the domestic dog. and do not participate in lethal inter-group aggression or kill within their own group. The most distinctive features of a bonobo are its cranium, which is 15% smaller than a chimpanzee's, and its less aggressive and more playful behavior. In other examples, the guinea pig's cranium is 13% smaller than its wild cousin the cavy, and domestic fowl show a similar reduction to their wild cousins. Possession of a smaller cranium for holding a smaller brain is a telltale sign of domestication. Bonobos appear to have domesticated themselves. In the farm fox experiment, humans selectively bred foxes against aggression, causing
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Origin of the domestic dog. domestication syndrome. The foxes were not selectively bred for smaller craniums and teeth, floppy ears, or skills at using human gestures, but these traits were demonstrated in the friendly foxes. Natural selection favors those that are the most successful at reproducing, not the most aggressive. Selection against aggression made possible the ability to cooperate and communicate among foxes, dogs and bonobos. Perhaps it did the same thing for humans. The more docile animals have been found to have less testosterone than their more aggressive counterparts, and testosterone controls aggression and brain size. One researcher has argued that in becoming more
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Origin of the domestic dog. social, we humans have developed a smaller brain than those of humans 20,000 years ago. Section:Dog domestication.:Dog and human convergent evolution. As a result of the domestication process there is also evidence of convergent evolution having occurred between dogs and humans. The history of the two is forever intertwined. Dogs suffer from the same diseases as humans, which include cancer, diabetes, heart disease, and neurological disorders. The underlying disease pathology is similar to humans, as is their responses and outcomes to treatment. Section:Dog domestication.:Dog and human convergent evolution.:Parallel evolution. There are patterns of genes which are related by their function
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Origin of the domestic dog. and these patterns can be found in both dogs and humans. This fact can be used to study the coevolution of gene function. Dogs accompanied humans when they first migrated into new environments. Both dogs and humans have adapted to different environmental conditions, with their genomes showing parallel evolution. These include adaptation to high altitude, low oxygen hypoxia conditions, and genes that play a role in digestion, metabolism, neurological processes, and some related to cancer. It can be inferred from those genes which act on the serotonin system in the brain that these have given rise to less aggressive behavior
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Origin of the domestic dog. when living in a crowded environment. In 2007, a study found that dog domestication was accompanied by selection at three genes with key roles in starch digestion: AMY2B, MGAMand SGLT1, and was a striking case of parallel evolution when coping with an increasingly starch-rich diet caused similar adaptive responses in dogs and humans. Section:Dog domestication.:Dog and human convergent evolution.:Behavioral evidence. Convergent evolution is when distantly related species independently evolve similar solutions to the same problem. For example, fish, penguins and dolphins have each separately evolved flippers as a solution to the problem of moving through the water. What has been
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Origin of the domestic dog. found between dogs and humans is something less frequently demonstrated: psychological convergence. Dogs have independently evolved to be cognitively more similar to humans than we are to our closest genetic relatives. Dogs have evolved specialized skills for reading human social and communicative behavior. These skills seem more flexible – and possibly more human-like – than those of other animals more closely related to humans phylogenetically, such as chimpanzees, bonobos and other great apes. This raises the possibility that convergent evolution has occurred: both "Canis familiaris" and "Homo sapiens" might have evolved some similar (although obviously not identical) social-communicative skills –
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Origin of the domestic dog. in both cases adapted for certain kinds of social and communicative interactions with human beings. The pointing gesture is a human-specific signal, is referential in its nature, and is a foundation building-block of human communication. Human infants acquire it weeks before the first spoken word. In 2009, a study compared the responses to a range of pointing gestures by dogs and human infants. The study showed little difference in the performance of 2-year-old children and dogs, while 3-year-old children's performance was higher. The results also showed that all subjects were able to generalize from their previous experience to respond to
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Origin of the domestic dog. relatively novel pointing gestures. These findings suggest that dogs demonstrating a similar level of performance as 2-year-old children can be explained as a joint outcome of their evolutionary history as well as their socialization in a human environment. Later studies support coevolution in that dogs can discriminate the emotional expressions of human faces, and that most people can tell from a bark whether a dog is alone, being approached by a stranger, playing, or being aggressive, and can tell from a growl how big the dog is. In 2015, a study found that when dogs and their owners interact, extended
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Origin of the domestic dog. eye contact (mutual gaze) increases oxytocin levels in both the dog and its owner. As oxytocin is known for its role in maternal bonding, it is considered likely that this effect has supported the coevolution of human-dog bonding. One observer has stated, "The dog could have arisen only from animals predisposed to human society by lack of fear, attentiveness, curiosity, necessity, and recognition of advantage gained through collaboration...the humans and wolves involved in the conversion were sentient, observant beings constantly making decisions about how they lived and what they did, based on the perceived ability to obtain at a given
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Origin of the domestic dog. time and place what they needed to survive and thrive. They were social animals willing, even eager, to join forces with another animal to merge their sense of group with the others' sense and create an expanded super-group that was beneficial to both in multiple ways. They were individual animals and people involved, from our perspective, in a biological and cultural process that involved linking not only their lives but the evolutionary fate of their heirs in ways, we must assume, they could never have imagined. Powerful emotions were in play that many observers today refer to as love –
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Origin of the domestic dog. boundless, unquestioning love." Section:Dog domestication.:Dog and human convergent evolution.:Human adoption of some wolf behaviors. In 2002, a study proposed that immediate human ancestors and wolves may have domesticated each other through a strategic alliance that would change both respectively into humans and dogs. The effects of human psychology, hunting practices, territoriality and social behavior would have been profound. Early humans moved from scavenging and small-game hunting to big-game hunting by living in larger, socially more-complex groups, learning to hunt in packs, and developing powers of cooperation and negotiation in complex situations. As these are characteristics of wolves, dogs and humans,
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Origin of the domestic dog. it can be argued that these behaviors were enhanced once wolves and humans began to cohabit. Communal hunting led to communal defense. Wolves actively patrol and defend their scent-marked territory, and perhaps humans had their sense of territoriality enhanced by living with wolves. One of the keys to recent human survival has been the forming of partnerships. Strong bonds exist between same-sex wolves, dogs and humans and these bonds are stronger than exist between other same-sex animal pairs. Today, the most widespread form of inter-species bonding occurs between humans and dogs. The concept of friendship has ancient origins but it
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Origin of the domestic dog. may have been enhanced through the inter-species relationship to give a survival advantage. In 2003, a study compared the behavior and ethics of chimpanzees, wolves and humans. Cooperation among humans' closest genetic relative is limited to occasional hunting episodes or the persecution of a competitor for personal advantage, which had to be tempered if humans were to become domesticated. The closest approximation to human morality that can be found in nature is that of the gray wolf, "Canis lupus". Wolves are among the most gregarious and cooperative of animals on the planet, and their ability to cooperate in well-coordinated drives
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Origin of the domestic dog. to hunt prey, carry items too heavy for an individual, provisioning not only their own young but also the other pack members, babysitting etc. are rivaled only by that of human societies. Similar forms of cooperation are observed in two closely related canids, the African wild dog and the Asian dhole, therefore it is reasonable to assume that canid sociality and cooperation are old traits that in terms of evolution predate human sociality and cooperation. Today's wolves may even be less social than their ancestors, as they have lost access to big herds of ungulates and now tend more toward
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Origin of the domestic dog. a lifestyle similar to coyotes, jackals, and even foxes. Social sharing within families may be a trait that early humans learned from wolves, and with wolves digging dens long before humans constructed huts it is not clear who domesticated whom. On the mammoth steppe the wolf's ability to hunt in packs, to share risk fairly among pack members, and to cooperate moved them to the top of the food chain above lions, hyenas and bears. Some wolves followed the great reindeer herds, eliminating the unfit, the weaklings, the sick and the aged, and therefore improved the herd. These wolves had
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Origin of the domestic dog. become the first pastoralists hundreds of thousands of years before humans also took to this role. The wolves' advantage over their competitors was that they were able to keep pace with the herds, move fast and enduringly, and make the most efficient use of their kill by their ability to "wolf down" a large part of their quarry before other predators had detected the kill. The study proposed that during the Last Glacial Maximum, some of our ancestors teamed up with those pastoralist wolves and learned their techniques. Many of our ancestors remained gatherers and scavengers, or specialized as fish-hunters,
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Origin of the domestic dog. hunter-gatherers, and hunter-gardeners. However, some ancestors adopted the pastoralist wolves' lifestyle as herd followers and herders of reindeer, horses, and other hoofed animals. They harvested the best stock for themselves while the wolves kept the herd strong, and this group of humans was to become the first herders and this group of wolves was to become the first dogs. Section:First dogs. The dog was the first species and the only large carnivore to have been domesticated. Over the past 200 years, dogs have undergone rapid phenotypic change and were formed into today's modern dog breeds due to artificial selection imposed
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Origin of the domestic dog. by humans. These breeds can vary in size and weight from a teacup poodle to a giant mastiff. The skull, body, and limb proportions vary significantly between breeds, with dogs displaying more phenotypic diversity than can be found within the entire order of carnivores. Some breeds demonstrate outstanding skills in herding, retrieving, scent detection, and guarding, which demonstrates the functional and behavioral diversity of dogs. There have been major advances in understanding the genes that gave rise to the phenotypic traits of dogs. The first dogs were certainly wolflike, however the phenotypic changes that coincided with the dog–wolf genetic divergence
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Origin of the domestic dog. are not known. Section:First dogs.:Bonn–Oberkassel dog. In 1914, on the eve of the First World War, two human skeletons were discovered during basalt quarrying at Oberkassel, Bonn in Germany. With them were found a right mandible of a "wolf" and other animal bones. After the end of the First World War, in 1919 a full study was made of these remains. The mandible was recorded as ""Canis lupus", the wolf" and some of the other animal bones were assigned to it. The remains were then stored and forgotten for fifty years. In the late 1970s there was renewed interest in
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Origin of the domestic dog. the Oberkassel remains and the mandible was re-examined and reclassified as belonging to a domesticated dog. The mitochondrial DNA sequence of the mandible was matched to "Canis lupus familiaris" - dog, and confirms that the Oberkassel dog is a direct ancestor of today's dogs. The bodies were dated to 14,223 YBP. This implies that in Western Europe there were morphologically and genetically "modern" dogs in existence around 14,500 years ago. Later studies assigned more of the other animal bones to the dog until most of a skeleton could be assembled. The humans were a man aged 40 years and a
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Origin of the domestic dog. woman aged 25 years. All three skeletal remains were found covered with large 20 cm thick basalt blocks and were sprayed with red hematite powder. The consensus is that a dog was buried along with two humans. A tooth belonging to a smaller and older dog was also identified but it had not been sprayed with red powder. The cause of the death of the two humans is not known. A pathology study of the dog remains suggests that it had died young after suffering from canine distemper between ages 19 and 23 weeks. The dog could not have survived
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Origin of the domestic dog. during this period without intensive human care. During this period the dog was of no utilitarian use to humans, and suggests the existence of emotional or symbolic ties between these humans and this dog. In conclusion, near the end of the Late Pleistocene at least some humans regarded dogs not just materialistically, but had developed emotional and caring bonds for their dogs. Section:First dogs.:First dogs as a hunting technology. During the Upper Paleolithic (50,000-10,000 YBP), the increase in human population density, advances in blade and hunting technology, and climate change may have altered prey densities and made scavenging crucial to
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Origin of the domestic dog. the survival of some wolf populations. Adaptations to scavenging such as tameness, small body size, and a decreased age of reproduction would reduce their hunting efficiency further, eventually leading to obligated scavenging. Whether these earliest dogs were simply human-commensal scavengers or they played some role as companions or hunters that hastened their spread is unknown. Researchers have proposed that in the past a hunting partnership existed between humans and dogs that was the basis for dog domestication. Petroglyph rock art dating to 8,000 YBP at the sites of Shuwaymis and Jubbah, in northwestern Saudi Arabia, depict large numbers of dogs
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Origin of the domestic dog. participating in hunting scenes with some being controlled on leashes. The transition from the Late Pleistocene into the early Holocene was marked by climatic change from cold and dry to warmer, wetter conditions and rapid shifts in flora and fauna, with much of the open habitat of large herbivores being replaced by forests. In the early Holocene, it is proposed that along with changes in arrow-head technology that hunting dogs were used by hunters to track and retrieve wounded game in thick forests. The dog's ability to chase, track, sniff out and hold prey can significantly increase the success of
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Origin of the domestic dog. hunters in forests, where human senses and location skills are not as sharp as in more open habitats. Dogs are still used for hunting in forests today. Section:First dogs.:Dogs enter North America from Siberia. In North America, the earliest dog remains were found in Illinois and radiocarbon dating indicates 9,900 YBP. These include three isolated burials at the Koster Site near the lower Illinois River in Greene County, and one burial 35 km away at the Stilwell II site in Pike County. These dogs were medium-sized adults around in height and around in weight, with very active lifestyles and varied
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Origin of the domestic dog. morphologies. Isotope analysis can be used to identify some chemical elements, allowing researchers to make inferences about the diet of a species. An isotope analysis of bone collagen indicates a diet consisting largely of freshwater fish. Similar dog burials across Eurasia are thought to be due to the dog’s importance in hunting to people who were trying to adapt to the changing environments and prey species during the Pleistocene-Holocene transition. In these places, the dog had gained an elevated social status. In 2018, a study compared sequences of North American dog fossils with Siberian dog fossils and modern dogs. The
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Origin of the domestic dog. nearest relative to the North American fossils was a 9,000 YBP fossil discovered on Zhokhov Island, arctic north-eastern Siberia, which was connected to the mainland at that time. The study inferred from mDNA that all of the North American dogs shared a common ancestor dated 14,600 YBP, and this ancestor had diverged along with the ancestor of the Zhokhov dog from their common ancestor 15,600 YBP. The timing of the Koster dogs shows that dogs entered North America from Siberia 4,500 years after humans did, were isolated for the next 9,000 years, and after contact with Europeans these no longer
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Origin of the domestic dog. exist because they were replaced by Eurasian dogs. The pre-contact dogs exhibit a unique genetic signature that is now gone, with nDNA indicating that their nearest genetic relatives today are the arctic breed dogs - Alaskan malamutes, Greenland dogs, and Alaskan huskies and Siberian huskies. Section:First dogs.:First dog breeds developed in Siberia. In 2017, a study showed that 9,000 YBP the domestic dog was present at what is now Zhokhov Island. The dogs were selectively bred as either sled dogs or as hunting dogs, which implies that a sled dog standard and a hunting dog standard existed at that time.
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Origin of the domestic dog. The optimal maximum size for a sled dog is 20–25 kg based on thermo-regulation, and the ancient sled dogs were between 16–25 kg. The same standard has been found in the remains of sled dogs from this region 2,000 YBP and in the modern Siberian husky breed standard. Other dogs were more massive at 30 kg and appear to be dogs that had been crossed with wolves and used for polar bear hunting. At death, the heads of the dogs had been carefully separated from their bodies by humans, probably for ceremonial reasons. The study proposes that after having diverged
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Origin of the domestic dog. from the common ancestor along with the grey wolf, the evolution of "Canis familiaris" proceeded in three stages. The first was natural selection based on feeding behavior within the ecological niche that had been formed through human activity. The second was artificial selection based on tamability. The third was directed selection based on forming breeds that possessed qualities to help with specific tasks within the human economy. The process commenced 40,000-30,000 YBP with its speed increasing with each stage until domestication became complete. Section:First dogs.:Dogs enter Japan. In Japan, temperate deciduous forests rapidly spread onto the main island of Honshu
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Origin of the domestic dog. and caused an adaption away from hunting megafauna (Naumann's elephant and Yabe's giant deer) to hunting the quicker sika deer and wild boar in dense forest. With this came a change in hunting technology, including a shift to smaller, triangular points for arrows. A study of the Jōmon people that lived on the Pacific coast of Honshu during the early Holocene shows that they were conducting individual dog burials and were probably using dogs as tools for hunting sika deer and wild boar, as hunters in Japan still do today. Hunting dogs make major contributions to forager societies and the
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Origin of the domestic dog. ethnographic record shows them being given proper names, treated as family members, and considered separate to other types of dogs. This special treatment includes separate burials with markers and grave-goods, with those that were exceptional hunters or that were killed on the hunt often venerated. A dog's value as a hunting partner gives them status as a living weapon and the most skilled elevated to taking on a "personhood", with their social position in life and in death similar to that of the skilled hunters. Intentional dog burials together with ungulate hunting is also found in other early Holocene deciduous
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Origin of the domestic dog. forest forager societies in Europe and North America, indicating that across the Holarctic temperate zone hunting dogs were a widespread adaptation to forest ungulate hunting.
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