Domestication of the dog

The domestication of the dog was the process which led to the domestic dog. Dogs are special animals because they were the first pets that humans had. All dogs today come from an old type of wolf that is no longer alive. These wolves were different from the wolves we know now, and they slowly changed to become the dogs we love today.

The change from wolf to dog happened between 20,000 and 40,000 years ago, around the time when the world was going through a big cold period called the Last Glacial Maximum. Dogs are similar to grey wolves, but they are their own group now. This happened because over many years, some wolves started to live closer to humans. These wolves were less scared of people and were friendlier, which helped them survive better.

Dogs were very important for humans, especially for people who moved around a lot to find food, called hunter–gatherers. Dogs could help watch for danger, bring back things, and even warn about problems. Because of these helpful wolves, humans and dogs began to live together. This friendship between humans and dogs is one of the biggest changes in human history, showing how animals and people can work together and help each other.

Timing

Dogs were first tamed long before farming began. Around 11,400 years ago, during a time called the Holocene, people in the Near East started to live with wild animals like aurochs, boar, sheep, and goats. We are still learning where dogs were first tamed, but most signs point to places in Eurasia such as Central Asia, East Asia, and Western Europe.

The oldest bones of dogs have been found in Western Europe, from places like the Erralla site in Spain. These dogs lived during cultures such as the Magdalenian, Epigravettian, Azilian, and Laborian. One famous example is the Bonn–Oberkassel dog, which lived about 14,500 years ago and was buried with a person. Other old dog bones have been found in places like Grotta Paglicci and Kesslerloch.

By the end of the last Ice Age about 11,700 years ago, different groups of early dogs had spread to places like the Levant, Karelia, near Lake Baikal, and even ancient America. New studies suggest that dogs may have been first tamed in Siberia between 26,000 and 19,700 years ago, and then spread to other parts of the world. But more digging is needed to find very old dog bones from that time and place.

Divergence from wolves

The grey wolf is the closest living relative of the dog. Scientists study DNA from modern dogs and wolves to learn about the dog's history, but it is tricky. This is because dogs come from an extinct type of wolf, not the modern ones we see today. The split between the dog's ancestor and modern wolves happened a long time ago, making it hard to know exactly when. This is also made harder by dogs mixing with wolves after they were first tamed. There have not been many generations of dogs since they were first tamed, which makes it even harder to know when this happened.

During the Late Pleistocene era, a time when the world was very cold, grey wolves had fewer numbers than before. But they survived when many other big animals did not. Grey wolves looked different in size and shape, maybe because of what they ate. Some ancient wolves had features that suggest they ate bones and carcasses, which may have helped them survive.

For a long time, scientists thought that dogs came from the modern grey wolf. But a study in 2014 showed that dogs actually come from an extinct type of wolf. The genetic evidence shows that the split between the line that led to the domestic dog and modern wolves happened between 20,000 and 40,000 years ago. This gives us a latest time when domestication may have started, though it probably began later.

Recent studies suggest that dogs may have come from different places, like Southeast Asia, Central Asia, the Middle East, and Europe. The genetic diversity among dogs from Southeast Asia is greater, suggesting this area may have been an important place where dogs first appeared. However, fossil evidence of dogs in Europe dates back to around 17,000 years ago, while fossils in far eastern Russia are only about 12,000 years old. This difference might be because fossils did not preserve well in all regions.

Overall, where and when dogs first came from is still being studied. Both genetic and fossil records help us learn more about how dogs first separated from their wild ancestors.

Dog domestication

Animal domestication is when animals change to live better with humans. Dogs were the first animals to live with people. This started more than 17,000 years ago with wolves. It happened before people had farms or other animals like cows and sheep.

Scientists think dogs began living with humans about 25,000 years ago. They came from wolves in places like Europe or Asia. We know dogs came from wolves, but we are still learning exactly when and where this happened. Over time, dogs changed in size and looks from their wolf ancestors. They became very important to early humans and helped people live and travel.

Dogs and humans share a special bond. They both live in groups and can work together. Some think dogs stayed close to humans because they were friendly. Others believe wolves followed humans for food and safety. Either way, dogs and humans helped each other survive.

First dogs

Dogs domesticated in East Asia

Savolainen’s study of mitochondrial DNA shows that dog domestication began in China or Southeast Asia around 33,000 years ago. A second phase happened 18,000 years later, with dogs moving from Southeast Asia to Africa and the Middle East. They reached Europe about 10,000 years ago, leading to modern dog breeds.

Savolainen noted that many studies contradicting the East Asian origin of dogs did not include samples from China or Southeast Asia.

Dogs domesticated in Siberia 23,000 years ago

Locating the origin of dogs is hard because of limited data on ancient wolves, small changes during early domestication, and a lack of human items with them.

In 2016, a genetic study found that ancient and modern dogs belong to Eastern and Western Eurasian groups. Another 2017 study suggested a single split between dogs and wolves between 36,900 and 41,500 years ago. This was followed by a split between Eastern and Western Eurasian dogs 17,500–23,900 years ago, showing dog domestication happened between 20,000 and 40,000 years ago.

A 2021 review suggests dogs were domesticated in Siberia 23,000 years ago by ancient North Siberians. These dogs later spread with human movements into the Americas and across Eurasia. The harsh climate may have brought humans and wolves closer together, leading to domestication.

Mitochondrial DNA shows most modern dogs belong to four groups: A, B, C, and D, with most in group A. The oldest known split in dog families happened around 22,800 years ago within group A. Human and dog movements often matched, suggesting dogs followed human travel.

A 2018 study of complete mitogenome sequences from 555 modern and ancient dogs showed a population increase around 23,500 years ago, matching the proposed split of dogs from wolves. A big increase happened after 15,000 years ago, matching human population growth.

Admixture

Studies show mixing between the ancestor of dogs and wolves and golden jackals. Since domestication, there has been little mixing from wolves to dogs but significant mixing from dogs to wolves. Some wolves are related to ancient and modern dogs. Small amounts of mixing were found between coyotes and ancient American dogs, and between African wolves and African dogs. East Asian wolves have 20% dog DNA, while European and Middle Eastern wolves have 7–25%. The β-defensin gene for black coat colour in North American wolves came from early Native American dogs between 1,600 and 7,200 years ago. Dogs and wolves in the Himalayas and Tibetan Plateau carry the EPAS1 gene for high-altitude living from an unknown wolf-like animal. This animal contributed 39% to the Himalayan wolf’s DNA. Limited mixing happened in arctic dogs.

Magdalenian dogs

The earliest Palaeolithic dog-human burial was found in 1914 at the Magdalenian site of Bonn-Oberkassel, Germany. The dog, dated to 14,223 years ago, was not a local wolf. Other dog remains from the Magdalenian and Azilian cultures are older, such as Erralla in Spain (17,410–17,096 years ago) and Abri le Morin in France (15,132–14,155 years ago).

The Erralla dog, found in 1985, was confirmed as a dog through testing and studies. It belonged to mitochondrial group C, shared with other Palaeolithic Western European dogs, including the Bonn-Oberkassel dog. This suggests Magdalenian hunter-gatherers brought dogs during their expansion from the Franco-Cantabrian region after the Last Glacial Maximum.

The Bonn-Oberkassel dog was buried with two humans, a man aged 40 and a woman aged 25, covered with red hematite powder and basalt blocks. The dog died young from canine distemper and could not have survived without human care, showing bonds between humans and dogs.

Ice Age dogs

Sequencing of ancient dog DNA shows they share a common family from an extinct wolf group different from modern wolves. By the end of the last Ice Age (11,700 years ago), five family lines spread, seen in dog samples from the Neolithic Levant (7,000 years ago), Mesolithic Karelia (10,900 years ago), Mesolithic Baikal (7,000 years ago), ancient America (4,000 years ago), and the New Guinea singing dog (present day).

Modern dog groups are split into Arctic/Americas, East Asian, and West Eurasian lines. The Arctic/Americas line includes modern arctic breeds, a 9,500-year-old Zhokhov Island dog, ancient pre-European contact American dogs, mid-Holocene Lake Baikal dogs, historical Siberian dogs, and Yamalo-Nenets Autonomous Okrug dogs. The East Asian line includes dogs from China, Vietnam, Island Southeast Asia, the dingo, and the New Guinea singing dog. The West Eurasian line includes ancient Levantine and Near Eastern dogs, ancient and modern European dogs, modern African dogs, and Bronze Age Eurasian Steppe dogs.

Ancient and modern European dogs are more closely related to arctic dogs than Near Eastern dogs, showing a major mixing event in Europe. A Mesolithic Veretye, Karelia dog (~10,000 years ago) had DNA from both Arctic (~70%) and Western Eurasian (~30%) lines. The Zhokhov Island dog (9,500 years ago) had no Western Eurasian DNA, showing it had not yet reached the Siberian Arctic. The 7,000-year-old Neolithic European dog was a mix of Karelian and Levantine lines, and a 5,000-year-old Swedish Neolithic dog was the ancestor of 90-100% of modern European dogs, suggesting a population change in Europe.

Siberian dogs from 9,500–7,000 years ago showed Arctic DNA, but later dogs from the Eurasian Steppe and Europe caused mixing. Bronze Age Eurasian Steppe dogs had 40% ancient arctic and 60% ancient Near East DNA. Yamalo-Nenets dogs from 2,000 years ago were less related to Eurasian Steppe and European dogs than those from 1,000 years ago, showing connections through trade. Siberian Huskies are related to historical East Siberian and ancient Lake Baikal dogs, showing the survival of the ancient arctic line in some modern breeds.

Ancient dog and human DNA often matched, but some differences existed. Dogs in the Neolithic Levant and Chalcolithic Iran had the same dogs despite different human groups. Neolithic Irish and German dogs were linked to northern European hunter-gatherers, while humans were related to Levantine people. Bronze Age Pontic-Caspian steppe and Corded Ware culture dogs in Germany did not change with human population shifts. European dogs are more closely related to Siberian and ancient American dogs than to the New Guinea singing dog, showing early links between humans in the Americas and Europe. Lake Baikal region humans 18,000–24,000 years ago contributed to Native American ancestry but were later replaced. By 7,000 years ago, Lake Baikal dogs still showed links with Europe and the Americas, indicating shared family structures for dogs and humans across northern Eurasia.

A big change in ancient human DNA matched with Neolithic farmer movements from the Near East into Europe, bringing dogs. Steppe pastoralist movements changed human DNA but had little effect on European dog groups. Steppe pastoralists also moved east but had little effect on East Asian people. Many Chinese dogs come from mixing between a 3,800-year-old western Eurasian Srubnaya culture dog and the ancestor of the dingo and New Guinea singing dog. Modern Siberian dogs show DNA from 7,000-year-old Lake Baikal dogs but little New Guinea singing dog DNA.

The AMY2B gene helps with starch digestion. Early dogs had varying abilities to digest starch, which became common thousands of years later with farming.

Dogs moved with humans but not always together, sometimes moving between human groups as cultural or trade items. Dogs spread across Eurasia and into the Americas without major human population movements, remaining a mystery.

First dogs as a hunting technology

During the Upper Paleolithic (50,000–10,000 years ago), more humans, new technology, and climate change changed prey numbers, making scavenging important for some wolves. Changes like tameness, small size, and lower reproduction age reduced hunting efficiency, leading to required scavenging. Whether the earliest dogs were scavengers or had roles as friends or hunters in their spread is unknown.

Researchers suggest a hunting partnership between humans and dogs drove domestication. Rock drawings from 8,000 years ago in Saudi Arabia show dogs in hunting scenes, sometimes on leashes. The change from the Late Pleistocene to the early Holocene brought warmer, wetter conditions and forest growth, replacing open areas. In these forests, hunting dogs helped track and retrieve wounded animals, improving hunting success where human senses were less effective. Dogs are still used for hunting in forests today.

Arctic breeds

First dog breeds developed in arctic northeastern Siberia

The domestic dog was present on Zhokhov Island, arctic northeastern Siberia, 9,500 years ago. Archaeological finds include dog harness straps like modern Inuit ones, polar bear and reindeer remains showing wide hunting ranges, and obsidian tools from 1,500 km away, suggesting long-distance travel with sled dogs.

Studies show these dogs were specially bred as sled or hunting dogs, with sled dogs best sized at 20–25 kg for temperature control. Ancient sled dogs weighed 16–25 kg, matching modern Siberian husky standards. Other dogs, heavier at 30 kg, were mixed with wolves for polar bear hunting. Dog heads were removed from bodies for ceremonial reasons.

The study suggests dog evolution happened in three stages after splitting from wolves: natural selection based on feeding behavior, artificial selection based on friendliness, and directed selection for specific tasks. This process began 30,000–40,000 years ago, speeding up until domestication was complete.

Zhokhov dogs are the oldest known with color patterns, showing black backs to differ from white arctic wolves.

Dogs enter North America from northeastern Siberia

Material culture shows dog harnessing in the Arctic 9,000 years ago. Ancient DNA shows these dogs are related to modern Arctic dogs and gave rise to the earliest native American dogs. European dogs later replaced these groups after contact.

The earliest North American dog remains were found in Lawyer's Cave, Alaska, dated to 10,150 years ago. Testing suggests a sea-based diet. The next earliest dogs were found in Illinois, dated to 9,900 years ago, with diets of freshwater fish. Similar dog burials across Eurasia show their importance in hunting for adjusting to changing environments during the Pleistocene-Holocene transition.

A 2018 study compared North American and Siberian dog fossils with modern dogs. North American dogs shared a common ancestor dated to 14,600 years ago, splitting from the Zhokhov dog ancestor 15,600 years ago. Koster dogs entered North America 4,500 years after humans, were isolated for 9,000 years, and were replaced by Eurasian dogs after European contact. Pre-contact dogs have a unique genetic sign now gone, with modern arctic breeds as their closest family.

A 2019 study found that dogs brought into the North American Arctic from northeastern Siberia were later replaced by Inuit dogs during their expansion 2,000 years ago. Inuit dogs were more genetically different and varied in shape. Arctic sledge dogs are descendants of pre-European dog lines. In 2020, testing showed Mexican breeds like the Chihuahua and Xoloitzcuintli keep 4% and 3% pre-colonial DNA, respectively.

Late Pleistocene wolf admixture

In 2015, the DNA of a 35,000-year-old Pleistocene wolf from the Taimyr Peninsula was tested and compared with modern dogs and wolves. The Taimyr wolf was equally related to dogs and modern wolves but shared more genes with high-latitude breeds like the Siberian husky and Greenland dog. Greenland dogs show 3.5% Taimyr wolf DNA, indicating mixing between Taimyr wolves and early dogs of these breeds. This suggests early dogs in cold areas changed through mixing, and modern arctic breeds come from many places.

A nuclear genome from a 4,800-year-old Newgrange dog in Ireland showed it was male, lacked modern coat length or color genes, processed starch less well than modern dogs but better than wolves, and had DNA from wolves not found in other dogs or wolves today. Testing rates from the Taimyr wolf and Newgrange dog suggest modern wolves and dogs split between 20,000 and 60,000 years ago, showing earlier domestication, earlier arrival in the Arctic, or both. Another idea suggests northern breeds trace DNA to the Taimyr wolf, showing possible many domestication events.

In 2020, the DNA of a 33,000-year-old Yana River wolf showed it was more closely related to the Taimyr wolf than to modern wolves, with DNA flow between Yana-Taimyr wolves and Pre-Columbian, Zhokhov, and modern sled dogs. No mixing between sled dogs and modern grey wolves happened in the last 9,500 years. Greenland sled dogs, separated since arriving with the Inuit 850 years ago, trace more DNA history to Zhokhov dogs than any other arctic breed. Sled dogs changed to eat high-fat diets, matching Inuit and arctic peoples' diets. This suggests sled dogs changed to low-starch, high-fat diets of their human friends.

In 2021, a study of four Late Pleistocene northeast Siberian wolves showed they are genetically similar to Taimyr and Yana wolves. These six old wolves split from the family leading to modern wolves and dogs. The 50,000-year-old Tirekhtyakh River, 48,000-year-old Bunge-Toll site, and 32,000-year-old Yana RHS specimens were different families. The 16,800-year-old Ulakhan Sular and 14,100-year-old Tumat specimens group with a modern Ellesmere Island wolf, showing they come from the same family as North American wolves. All six Late Pleistocene wolves share genes with Arctic dogs, suggesting another old wolf group may have added to Arctic dog DNA. Testing shows four old Siberian wolves added to modern wolf groups in Shanxi, China, and possibly Chukotka and Inner Mongolia.

Dogs enter Japan

The oldest dog fossil in Japan dates to 9,500 years ago. With the Holocene's warmer weather, warm forests spread across Honshu, changing hunting from big animals to sika deer and wild boar in thick forests. This led to changes in hunting tools, including smaller arrow points. Testing of Jōmon people on Honshu's Pacific coast shows they buried dogs alone and used dogs for hunting sika deer and wild boar, as seen in modern Japanese hunting.

Hunting dogs are important to hunter societies, often named, treated as family, and seen as different from other dogs. They get special burials with markers and gifts, with the best hunters or those killed on the hunt sometimes honored. A dog's value as a hunting friend gives them status as living weapons, with the best raised to "personhood," like skilled hunters in social position in life and death.

Intentional dog burials with ungulate hunting are also found in early Holocene warm forest hunter societies in Europe and North America, showing hunting dogs were a common way to hunt forest animals across the Holarctic warm zone.

Dogs enter Island Southeast Asia and Oceania

In 2020, an mDNA study of ancient dog fossils from the Yellow River and Yangtze River basins in southern China showed most ancient dogs were in group A1b, like Australian dingoes and pre-colonial Pacific dogs, but in low numbers today. A specimen from the Tianluoshan site (Hemudu culture) in Zhejiang, dating to 7,000 years ago, is at the base of the whole line. Dogs in this group were once common in southern China, then moved through Southeast Asia into New Guinea and Oceania but were replaced in China 2,000 years ago by other groups.

Dogs entered Island Southeast Asia, Australia, and New Guinea in at least two waves: one with Paleolithic sea hunter-gatherers by at least 10,000 to 5,000 years ago, and another with Neolithic sea-faring Austronesian peoples via Taiwan by at least 5,000 years ago. Neolithic dogs could digest starch, showing they moved with humans growing grain crops. The oldest archaeological dog remains in Island Southeast Asia and Oceania are a dog burial in Timor and dingo remains in Australia, both dated to around 3,500 years ago. The former are believed to be from the second wave, and the latter from the first. Austronesian dogs, like the Taiwan dog, were valued as hunting friends, especially for wild boar. In the Philippines, dog remains have been found buried near or beside human graves.

From Island Southeast Asia, Austronesian travelers carried dogs into Near Oceania. However, unlike in Island Southeast Asia, dogs lost economic value as hunting animals in Melanesia and Polynesia, which lacked large animals. They became food competitors and were eaten. Austronesian dogs carried by Lapita Culture migrations went extinct in many islands. Thus, Austronesian dogs were “lost” during early Near Oceania settlement, causing a break in dog DNA and words among Austronesians in the Pacific Islands and Island Melanesia compared to other places. Dogs were later brought back from Papuan groups and carried eastward into Polynesia by post-Lapita movements, reaching Hawaii and Aotearoa. These dogs were food animals, not hunting friends. Genetic testing confirms Polynesian dogs come from the first wave and are not related to Taiwan and Philippines dogs.

Dogs from the Near East enter Africa

In 2020, ancient dog DNA testing showed that modern sub-Saharan African dogs come from the Levant, with an ancient example dated to 7,000 years ago. This matches human and cattle DNA moving from the Levant into Africa during the Neolithic. Since then, there has been little DNA flow into African dogs until recent times. Descendants of a 5,800-year-old Iranian dog and European dogs replaced the Levant dog line 2,300 years ago, linked to human movement from Iran and small European movement. Today, Near Eastern dogs show 81% ancient Iranian and 19% Neolithic European DNA.

The oldest African dog remains date to 5,900 years ago at Merimde Beni-Salame in Egypt. The next oldest are from Esh Shareinab in Sudan, dated to 5,500 years ago, showing dogs arrived from Asia with domestic sheep and goats. Dogs spread north to south with livestock keepers, with remains found at Ntusi in Uganda (925–1,055 years ago), Kalomo in Zambia (950–1,000 years ago), and southern Africa. In 2020, ancient dog DNA testing showed the southern African Rhodesian Ridgeback keeps 4% pre-colonial DNA.