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An Arctic wolf/Alaskan Malamute hybrid from Lobo Park, Antequera
Dog ( domestic dog )

A wolfdog is a canine produced by the mating of a domestic dog (Canis familiaris) with a gray wolf (Canis lupus), eastern wolf (Canis lycaon), red wolf (Canis rufus), or Ethiopian wolf (Canis simensis) to produce a hybrid.



Hybrids in eastern Poland in the Wildlife Park Kadzidlowo. To the left: Parents: female wolf and male Gonczy Polski; right: parents: female wolf and male West Siberian Laika. F1 wolf-dog hybrids from Wildlife Park Kadzidlowo, Poland.png
Hybrids in eastern Poland in the Wildlife Park Kadzidłowo. To the left: Parents: female wolf and male Gończy Polski; right: parents: female wolf and male West Siberian Laika.

There are a range of experts who believe that they can tell the difference between a wolf, a dog, and a wolfdog, but they have been proven to be incorrect when providing their evidence before courts of law. [1]

Admixture between domestic dogs and other subspecies of gray wolves are the most common wolfdogs since dogs and gray wolves are considered the same species, are genetically very close and have shared vast portions of their ranges for millennia. Such admixture in the wild have been detected in many populations scattered throughout Europe and North America, usually occurring in areas where wolf populations have declined from human impacts and persecutions. [2] [3]

At the same time, wolfdogs are also often bred in captivity for various purposes. Admixture of dogs and two other North American wolf species have also occurred historically in the wild, although it is often difficult for biologists to discriminate the dog genes in the eastern timber and red wolves from the gray wolf genes also present in these wolf species due to their historical overlaps with North American gray wolves as well as with coyotes, both of which have introgressed into the eastern timber and red wolf gene pools. [4] At the same time, because many isolated populations of the three wolf species in North America have also mixed with coyotes in the wild, [5] it has been speculated by some biologists that some of the coywolf hybrids in the northeastern third of the continent may also have both coydogs and wolfdogs in their gene pool. [6] Hybrids between dogs and Ethiopian wolves discovered in the Ethiopian Highlands likely originated from past interactions between free-roaming feral dogs and Ethiopian wolves living in isolated areas. [7]

Recognized wolfdog breeds by the FCI are the Czechoslovakian Wolfdog and the Saarloos Wolfdog.


Whole genome sequencing has been used to study gene flow between wild and domestic species. There is evidence of widespread gene-flow from dogs into wolf populations, and very few deliberate crossings of wolves with dogs, such as the Saarloos Wolfdog. However, the global dog population forms a genetic cluster with little evidence for gene flow from wolves into dogs. Ancient DNA shows that dogs from Europe over 5,000 years ago also show little evidence of interbreeding with wild canids. [8]

Prehistoric wolfdogs

A 1982 study of canine skulls from Wyoming dating back 10,000 years ago identified some that match the morphology of wolfdogs. [9] This study was rebutted as not providing convincing evidence four years later. [10]

Teotihuacan wolfdogs

In 2010, archeologists found the remains of wolf-dogs in a warrior's burial in Mexico's central valley that date about two thousand years ago, therefore what was once thought as coyotes depicted in Teotihuacan civilization art are being re-examined. [11]

New World black wolves

Genetic research has shown that wolves with black pelts owe their coloration to a mutation that first arose in domestic dogs. Blacklupus.jpg
Genetic research has shown that wolves with black pelts owe their coloration to a mutation that first arose in domestic dogs.

Genetic research revealed that wolves with black pelts owe their distinctive coloration to a mutation that entered the wolf population through admixture with the domestic dog. [12] Adolph Murie was among the first wolf biologists to speculate that the wide color variation in wolves was due to interbreeding with dogs; [13]

"I suppose that some of the variability exhibited in these wolves could have resulted from crossings in the wild with dogs. Such crosses in the wild have been reported and the wolf in captivity crosses readily with dogs. Some years ago at Circle, Alaska, a wolf hung around the settlement for some time and some of the dogs were seen with it. The people thought that the wolf was a female attracted to the dogs during the breeding period. However, considerable variability is probably inherent in the species, enough perhaps to account for the variations noted in the park and in skins examined. The amount of crossing with dogs has probably not been sufficient to alter much the genetic composition of the wolf population."

Murie, Adolph (1944). The Wolves of Mount McKinley. ISBN   0-295-96203-8, ISBN   978-0-295-96203-0.

In 2008 it was discovered that a gene mutation responsible for the protein beta-defensin 3 is responsible for the black coat color in dogs. [14] The same mutation was responsible for black wolves in North America and the Italian Apennines, with the mutation having arisen in dogs 13,000 to 120,000 years ago, with a preferred date of 47,000 years ago after comparing large sections of wolf, dog, and coyote genomes. [12] Robert K. Wayne, a canine evolutionary biologist, stated that he believed that dogs were the first to have the mutation. He further stated that even if it originally arose in Eurasian wolves, it was passed on to dogs who, soon after their arrival, brought it to the New World and then passed it to wolves and coyotes. [15] Black wolves with recent dog ancestry tend to retain black pigment longer as they age. [16]

North American gray wolf-domestic dog admixture

As of 1999 in the United States, over 100,000 wolfdogs exist. [17] In first-generation wolfdogs, gray wolves are most often crossed with wolf-like dogs (such as German Shepherd Dogs, Siberian Huskies, and Alaskan Malamutes) for an appearance most appealing to owners desiring an exotic pet. [18]

Documented breeding

"Mixed breed Dog and Wolf" from The Menageries: Quadrupeds Described and Drawn from Living Subjects by William Ogilby, 1829 Menagerieclupus.jpg
"Mixed breed Dog and Wolf" from The Menageries: Quadrupeds Described and Drawn from Living Subjects by William Ogilby, 1829

The first record of wolfdog breeding in Great Britain comes from the year 1766 when what is thought was a male wolf mated with a dog identified in the language of the day as a "Pomeranian", although it may have differed from the modern Pomeranian breed. The union resulted in a litter of nine pups. Wolfdogs were occasionally purchased by English noblemen, who viewed them as a scientific curiosity. Wolfdogs were popular exhibits in British menageries and zoos. [18]

Six breeds of dog exist that acknowledge a significant amount of recent wolf-dog admixture in their creation. One breed is the "wolamute", a.k.a. "malawolf", a cross between an Alaskan Malamute and a timber wolf. Four breeds were the result of intentional crosses with German Shepherd Dogs and have distinguishing characteristics of appearance that may reflect the varying subspecies of wolf that contributed to their foundation stock. Other, more unusual crosses have occurred; recent experiments in Germany were conducted in the crossing of wolves and Poodles. [19] The intent behind creating the breeds has ranged widely from simply the desire for a recognizable companion high-content wolfdog to professional military working dogs.

The Saarloos Wolfdog

A Saarloos Wolfdog Saarloos.jpg
A Saarloos Wolfdog

In 1932, Dutch breeder Leendert Saarloos crossed a male German Shepherd dog with a female European wolf. He then bred the female offspring back with the male German Shepherd Dog, creating the Saarloos wolfdog. The breed was created to be a hardy, self reliant companion and house dog. [20] The Dutch Kennel Club recognized the breed in 1975. To honor its creator they changed the name to "Saarloos Wolfdog". In 1981, the breed was recognized by the Fédération Cynologique Internationale (FCI).

The Czechoslovakian Wolfdog

A Czechoslovakian Wolfdog Czechoslovakian-wolfdog-profile big.jpg
A Czechoslovakian Wolfdog

In the 1950s, the Czechoslovakian Wolfdog was also created to work on border patrol in the countries now known as Slovakia and the Czech Republic. It was originally bred from lines of German Shepherd Dogs with Carpathian grey wolves. It was officially recognized as a national breed in Czechoslovakia in 1982, and later was recognized by the Fédération Cynologique Internationale, the American Kennel Club's Foundation Stock Service and the United Kennel Club, and today is used in agility, obedience, search and rescue, police work, therapy work, and herding in Europe and the United States.

The Volkonsoby Wolfdog

The Volkonsob, lit. Wolfhound in Russian, was initially developed in the 1990s after the fall of the Soviet Union. Russian border guards wanted a dog that would possess the trainability and pack mentality of the German Shepherd, combined with the strength, superior senses and cold-resistance of a wild wolf, able to cope in the harsh conditions of the vast Russian borders. In 2000, a Caspian Steppe Wolf, noted for being unusually friendly and cooperative towards humans, was bred with German Shepherds of an East European Shepherd line, until an F3 generation was standardised. Unlike the previous hybrids, the Volkonsob was the only breed that was an effective border guardian as they are renewing for not being too shy. [21]

Livestock guardian dogs

A 2014 study found that 20% of wolves and 37% of dogs shared the same mitochondrial haplotypes in Georgia. More than 13% of the studied wolves had detectable dog ancestry and more than 10% of the dogs had detectable wolf ancestry. The results of the study suggest that admixture between wolves and dogs is a common event in the areas where large livestock guardian dogs are held in a traditional way, and that gene flow between dogs and gray wolves was an important force influencing gene pool of dogs for millennia since early domestication events. [22]

Wolfdogs in the wild

Hybridization between wolves and dogs typically occurs when the wolf population is under strong hunting pressure and its structure is disrupted due to a high number of free-ranging dogs. Wolves typically display aggressiveness toward dogs, but a wolf can change its behaviour and become playful or submissive when it becomes socially isolated.

Admixture in the wild usually occurs near human habitations where wolf density is low and dogs are common. [23] However, there were several reported cases of wolfdogs in areas with normal wolf densities in the former Soviet Union. [24] Wild wolfdogs were occasionally hunted by European aristocracy, and were termed lycisca to distinguish them from common wolves. [25] Noted historic cases (such as the Beast of Gévaudan) of large wolves that were abnormally aggressive toward humans, may be attributable to wolf-dog mating. [26] In Europe, unintentional mating of dogs and wild wolves have been confirmed in some populations through genetic testing. As the survival of some Continental European wolf packs is severely threatened, scientists fear that the creation of wolfdog populations in the wild is a threat to the continued existence of European wolf populations. [27] However, extensive admixture between wolf and dog is not supported by morphological evidence, and analyses of mtDNA sequences have revealed that such mating are rare. [23]

In 1997, during the Mexican Wolf Arizona Reintroduction, controversy arose when a captive pack at Carlsbad designated for release was found by Roy McBride to be largely composed of wolf-dogs, who had captured many wolves for the recovery programme in the 1970s. Though staff initially argued that the animals' odd appearance was due to captivity and diet, it was later decided to euthanise them. [28]

In 2018, a study compared the sequences of 61,000  single-nucleotide polymorphisms (mutations) taken from across the genome of grey wolves. The study indicated that there exists individual wolves of dog-wolf ancestry in most of the wolf populations of Eurasia, but less so in North America. The admixture has been occurring across different time scales and was not a recent event. Low-level admixture did not reduce the wolf distinctiveness. [29]

In 2019, in the Osogovo mountainous region along the border between Bulgaria and North Macedonia a putative grey wolf was recorded by camera to be living with a pack of 10 feral dogs, and by its behaviour and phenotype was assumed to be a wolf-dog hybrid. [30]

Breed-specific legislation

The wolfdog has been the center of controversy for much of its history, and most breed-specific legislation is either the result of the animal's perceived danger or its categorization as protected native wildlife. [31] The Humane Society of the United States, the RSPCA, Ottawa Humane Society, the Dogs Trust, and the Wolf Specialist Group of the IUCN Species Survival Commission consider wolfdogs to be wild animals and therefore unsuitable as pets, and support an international ban on the private possession, breeding, and sale of wolfdogs. [18] [32] [33]

According to the National Wolfdog Alliance, 40 U.S. states effectively forbid the ownership, breeding, and importation of wolfdogs, while others impose some form of regulation upon ownership. [34] In Canada, the provinces of Alberta, Manitoba, Newfoundland, and Prince Edward Island prohibit wolfdogs as pets. [35] Most European nations have either outlawed the animal entirely or put restrictions on ownership. [36] Wolfdogs were among the breeds banned from the U.S. Marine Corps base at Camp Pendleton and elsewhere after a fatal dog attack by a pit bull on a child. [37]


Skeleton of a wolf-dog hybrid from the Museum national d'histoire naturelle Wolfhybridskeleton.jpg
Skeleton of a wolf-dog hybrid from the Muséum national d'histoire naturelle

The physical characteristics of an animal created by breeding a wolf to a dog are not predictable, similar to that of mixed-breed dogs. In many cases the resulting adult wolfdog may be larger than either of its parents due to the genetic phenomenon of heterosis (commonly known as hybrid vigor). [26] Breeding experiments in Germany with poodles and wolves, and later on with the resulting wolfdogs showed unrestricted fertility, mating via free choice and no significant problems of communication (even after a few generations). However, the offspring of poodles with either coyotes and jackals, all showed a decrease in fertility, significant communication problems, and an increase of genetic diseases after three generations of interbreeding between the hybrids. The researchers therefore concluded that domestic dogs and wolves are the same species. [19]

Wolfdogs display a wide variety of appearances, ranging from a resemblance to dogs without wolf blood to animals that are often mistaken for full-blooded wolves. A lengthy study by DEFRA and the RSPCA found several examples of misrepresentation by breeders and indeterminate levels of actual wolf pedigree in many animals sold as wolfdogs. The report noted that uneducated citizens misidentify dogs with wolf-like appearance as wolfdogs. [18] Wolfdogs tend to have somewhat smaller heads than pure wolves, with larger, pointier ears that lack the dense fur commonly seen in those of wolves. Fur markings also tend to be very distinctive and not well blended. Black-colored wolfdogs tend to retain black pigment longer as they age, compared to black wolves. [16] In some cases, the presence of dewclaws on the hind feet is considered a useful, but not absolute, indicator of dog gene contamination in wild wolves. Dewclaws are the vestigial first toes, which are common on the hind legs of domestic dogs but thought absent from pure wolves, which only have four hind toes. [27]

Observations on wild wolfdogs in the former Soviet Union indicate that in a wild state these may form larger packs than pure wolves, and have greater endurance when chasing prey. [38] High wolf-content wolfdogs typically have longer canine teeth than dogs of comparable size, with some officers in the South African Defence Force commenting that the animals are capable of biting through the toughest padding "like a knife through butter". [39]

Tests undertaken in the Perm Institute of Interior Forces in Russia demonstrated that high wolf-content wolfdogs took 15–20 seconds to track down a target in training sessions, whereas ordinary police dogs took 3–4 minutes. [40] The scientific evidence to support the claims by wolfdog researchers is minimal, and more research has been called for. [41]


Wolfdogs are generally said to be naturally healthy animals, and are affected by fewer inherited diseases than most breeds of dog. Wolfdogs are usually healthier than either parent due to heterosis. [26] There is some controversy over the effectiveness of the standard dog/cat rabies vaccine on a wolfdog. The USDA has not to date approved any rabies vaccine for use in wolfdogs, though they do recommend an off-label use of the vaccine. [42] Wolfdog owners and breeders purport that the lack of official approval is a political move to prevent condoning wolfdog ownership. [43]

Temperament and behavior

Wolfdogs are a mixture of genetic traits, which results in less predictable behavior patterns compared to either the wolf or dog. [26] The adult behavior of wolfdog pups also cannot be predicted with comparable certainty to dog pups, even in third-generation pups produced by wolfdog mating with dogs or from the behavior of the parent animals. [26] Thus, though the behavior of a single individual wolfdog may be predictable, the behavior of the type as a whole is not. [26]

Due to the variability inherent to their admixture, [26] whether a wolf–dog cross should be considered more dangerous than a dog depends on behavior specific to the individual alone rather than to wolfdogs as a group.

The view that aggressive characteristics are inherently a part of wolfdog temperament has been contested in recent years by wolfdog breeders and other advocates of wolfdogs as pets. [44] [45]

Further reading

See also

Related Research Articles

Coyote Species of canine native to North America

The coyote is a species of canine native to North America. It is smaller than its close relative, the wolf, and slightly smaller than the closely related eastern wolf and red wolf. It fills much of the same ecological niche as the golden jackal does in Eurasia. The coyote is larger and more predatory and was once referred to as the American jackal by a behavioral ecologist. Other historical names for the species include the prairie wolf and the brush wolf.

Canidae Family of mammals

Canidae is a biological family of dog-like carnivorans, colloquially referred to as dogs, and constitutes a clade. A member of this family is also called a canid. There are three subfamilies found within the canid family, which are the extinct Borophaginae and Hesperocyoninae, and the extant Caninae. The Caninae are known as canines, and include domestic dogs, wolves, foxes, coyotes and other extant and extinct species.

Red wolf Canid native to the southeastern United States

The red wolf is a canine native to the southeastern United States. Its size is intermediate between the coyote and gray wolf.

Wolf Type of canine

The wolf, also known as the gray wolf or grey wolf, is a large canine native to Eurasia and North America. More than thirty subspecies of Canis lupus have been recognized, and gray wolves, as popularly understood, comprise wild subspecies. The wolf is the largest extant member of the family Canidae. It is also distinguished from other Canis species by its less pointed ears and muzzle, as well as a shorter torso and a longer tail. The wolf is nonetheless related closely enough to smaller Canis species, such as the coyote and the golden jackal, to produce fertile hybrids with them. The banded fur of a wolf is usually mottled white, brown, gray, and black, although subspecies in the arctic region may be nearly all white.

<i>Canis</i> Genus of carnivores

Canis is a genus of the Caninae which includes multiple extant species, such as wolves, dogs, coyotes, and golden jackals. Species of this genus are distinguished by their moderate to large size, their massive, well-developed skulls and dentition, long legs, and comparatively short ears and tails.

Saarloos wolfdog Dog breed

The Saarloos Wolfdog is a wolf-dog breed originating from the Netherlands by the crossing of a German Shepherd with a Siberian grey wolf in 1935. The offspring were then further crossed with German Shepherds.

Eastern wolf Subspecies of carnivore

The eastern wolf also known as the timber wolf, Algonquin wolf or eastern timber wolf, is a canine of debated taxonomy native to the Great Lakes region and southeastern Canada. It is considered to be either a unique subspecies of grey wolf or red wolf or a separate species from both. Many studies have found the eastern wolf to be the product of ancient and recent genetic admixture between the gray wolf and the coyote, while other studies have found some or all populations of the eastern wolf, as well as coyotes, originally separated from a common ancestor with the wolf over 1 million years ago and that these populations of the eastern wolf may be the same species as or a closely related species to the red wolf of the Southeastern United States. Regardless of its status, it is regarded as unique and therefore worthy of conservation with Canada citing the population in eastern Canada as being the eastern wolf population subject to protection.

Ethiopian wolf Canine native to Ethiopian Highlands

The Ethiopian wolf, also known as the Simien jackal or Simien fox, is a canine native to the Ethiopian Highlands. In southeastern Ethiopia it is also known as the horse jackal. It is similar to the coyote in size and build, and is distinguished by its long and narrow skull, and its red and white fur. Unlike most large canids, which are widespread, generalist feeders, the Ethiopian wolf is a highly specialised feeder of Afroalpine rodents with very specific habitat requirements. It is one of the world's rarest canids, and Africa's most endangered carnivore.

Golden jackal Canid native to southeastern Europe, Asia and Arabia

The golden jackal is a wolf-like canid that is native to Eastern Europe, Southwest Asia, South Asia, and regions of Southeast Asia. Compared with the Arabian wolf, which is the smallest gray wolf subspecies, the jackal is smaller and possesses shorter legs, a shorter tail, a more elongated torso, a less-prominent forehead, and a narrower and more pointed muzzle. The golden jackal's coat can vary in color from a pale creamy yellow in summer to a dark tawny beige in winter. It is listed as Least Concern on the IUCN Red List due to its widespread distribution and high density in areas with plenty of available food and optimum shelter.


A coydog is a canid hybrid resulting from a mating between a male coyote and a female dog. Hybrids of both sexes are fertile and can be successfully bred through four generations. Similarly, a dogote is a hybrid with a dog father and a coyote mother.

Coywolf Hybrid mammal

Coywolf is an informal term for a canid hybrid descended from coyotes, eastern wolves and gray wolves. All members of the genus Canis are closely genetically related with 78 chromosomes and therefore can interbreed. One genetic study indicates that these two species genetically diverged relatively recently. Genomic studies indicate that nearly all North American gray wolf populations possess some degree of admixture with coyotes following a geographic cline, with the lowest levels occurring in Alaska, and the highest in Ontario and Quebec, as well as Atlantic Canada.

Canid hybrids are the result of interbreeding between the species of the genus Canis. This often occurs in the wild, and in particular between domestic or feral dogs with wild native canids.

Czechoslovakian Wolfdog Dog breed

The CzechoslovakianWolfdog is a wolf-dog breed that began as an experiment conducted in Czechoslovakia in 1955.

Domestication of the dog Aspect of history

The origin of the domestic dog includes the dog's genetic divergence from the wolf, its domestication, and the emergence of the first dogs. Genetic studies show that all ancient and modern dogs share a common ancestry and descended from an ancient, now-extinct wolf population – or closely related wolf populations – which was distinct from the modern wolf lineage. The dog's similarity to the grey wolf is the result of substantial dog-into-wolf gene flow, with the modern grey wolf being the dog's nearest living relative. An extinct Late Pleistocene wolf may have been the ancestor of the dog.

Japanese wolf Extinct subspecies of carnivore

The Japanese wolf, also known as the Honshū wolf, is an extinct subspecies of the gray wolf that was once endemic to the islands of Honshū, Shikoku and Kyūshū in the Japanese archipelago.

Black wolf Melanistic wolf

A black wolf is a melanistic colour variant of the gray wolf. Black specimens were recorded among red wolves, though the colour morph in this species is probably now extinct. Genetic research from the Stanford University School of Medicine and the University of California, Los Angeles revealed that wolves with black pelts owe their distinctive coloration to a mutation which occurred in domestic dogs, and was carried to wolves through wolf-dog hybridization. Besides coat and knee colour, they are normal grey wolves.

Dingo–dog hybrid An Australian hybrid animal

A dingo–dog hybrid is a hybrid cross between a dingo and a domestic dog. The current population of free ranging domestic dogs in Australia is now probably higher than in the past. However, the proportion of the so-called "pure" dingoes has been on the decrease over the last few decades due to hybridisation and is regarded as further decreasing.

Eastern coyote Coywolf native to the northeastern United States and eastern Canada

The eastern coyote is a wild North American canine hybrid with both coyote and wolf parentage. The hybridization likely first occurred in the Great Lakes region, as western coyotes moved east. It was first noticed during the early 1930s to the late 1940s, and likely originated in the aftermath of the extirpation of the gray wolf in southeastern Ontario, Labrador and Quebec, thus allowing coyotes to colonize the former wolf ranges, and mix with the remnant wolf populations. This hybrid is smaller than the eastern wolf and holds smaller territories, but is larger and holds more extensive home ranges than the typical western coyote.

Jackal–dog hybrid Canid hybrid resulting from a mating between a dog and a golden jackal

A jackal–dog hybrid is a canid hybrid resulting from a mating between a domestic dog and a golden jackal. Such crossbreeding has occurred numerous times in captivity and was first confirmed to occasionally happen in the wild in Croatia in 2015. It is believed that the domestic dog cannot hybridise with other species of jackal, outside of the Canis genus, namely the Side-striped jackal, or the Black-backed jackal.

Evolution of the wolf Overview article

The evolution of the wolf occurred over a geologic time scale of at least 300 thousand years. The grey wolf Canis lupus is a highly adaptable species that is able to exist in a range of environments and which possesses a wide distribution across the Holarctic. Studies of modern grey wolves have identified distinct sub-populations that live in close proximity to each other. This variation in sub-populations is closely linked to differences in habitat – precipitation, temperature, vegetation, and prey specialization – which affect cranio-dental plasticity.


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