A black wolf is a melanistic

Melanism

Melanism is an undue development of dark-colored pigment in the skin or its appendages, and the opposite of albinism. It is also the medical term for black jaundice.The word is deduced from the , meaning black pigment....

 color variant of the grey wolf

Gray Wolf

The gray wolf , also known as the wolf, is the largest extant wild member of the Canidae family...

 (Canis lupus). Black specimens are recorded among red wolves

Red Wolf

The red wolf is a North American canid which once roamed throughout the Southeastern United States and is a glacial period survivor of the Late Pleistocene epoch...

 (Canis rufus), but these color variants are probably extinct. Genetic research from the Stanford University School of Medicine

Stanford University School of Medicine

Stanford University School of Medicine is a leading medical school located at Stanford University Medical Center in Stanford, California. Originally based in San Francisco, California as Cooper Medical College, it is the oldest continuously running medical school in the western United States...

 and the University of California, Los Angeles

University of California, Los Angeles

The University of California, Los Angeles is a public research university located in the Westwood neighborhood of Los Angeles, California, USA. It was founded in 1919 as the "Southern Branch" of the University of California and is the second oldest of the ten campuses...

 revealed that wolves with black pelts owe their distinctive coloration to a mutation which occurred through wolf-dog hybridisation.

Europe

Linnaeus gave the black wolves of Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

 the binomial name Canis lycaon, under the assumption that the species was distinct from grey and white colored wolves. Cuvier

Georges Cuvier

Georges Chrétien Léopold Dagobert Cuvier or Jean Léopold Nicolas Frédéric Cuvier , known as Georges Cuvier, was a French naturalist and zoologist...

 and other naturalists largely followed his example. Black wolves were considered rare in France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

, but common in Southern Europe at the time, with black wolf populations south to the Pyrenees

Pyrenees

The Pyrenees is a range of mountains in southwest Europe that forms a natural border between France and Spain...

 apparently outnumbering other colour morphs. They also occurred in the mountains of Friuli

Friuli

Friuli is an area of northeastern Italy with its own particular cultural and historical identity. It comprises the major part of the autonomous region Friuli-Venezia Giulia, i.e. the province of Udine, Pordenone, Gorizia, excluding Trieste...

 and around Cattaro. Black wolves were also reported to inhabit the Vekvoturian Mountain of Russia

Russia

Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

. Colonel Smith believed that the so called "Rossomak" of the Lenas in Siberia

Siberia

Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...

 was of the same variety. Black wolves were considered rare in northern Europe, however, Dr Höggberg, a medical practitioner at Carlstad

Karlstad

Karlstad is a city, the seat of Karlstad Municipality, the capital of Värmland County, and the largest city in the province Värmland in Sweden. The city had 61,685 inhabitants in 2010 out of a municipal total that during the first quarter 2010 was 84,885 inhabitants...

 mentioned five black wolves being killed in the Scandinavia

Scandinavia

Scandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,...

n province of Wermeland

Värmland

' is a historical province or landskap in the west of middle Sweden. It borders Västergötland, Dalsland, Dalarna, Västmanland and Närke. It is also bounded by Norway in the west. Latin name versions are Vermelandia and Wermelandia. Although the province's land originally was Götaland, the...

 in 1801. These wolves were completely black, save for a white patch on the chest, and were smaller than the more common grey variety. Their pelts were considered exotic enough to be sold for 3–4 times the price established for more common colour morphs. Also, the last wolf in Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

, supposedly killed by MacQueen of Pall à Chrocain

MacQueen of Pall à Chrocain

MacQueen of Pall à Chrocain was a legendary Highland deer stalker popularly believed to have slain the last wolf in Scotland in 1743. The scene of the incident was Tarnaway Forest in the province of Morayshire in the county of Inverness...

 is usually narrated as having been black. Cuvier noted that European black wolves differed little in size from other colour morphs, but exceeded them in physical strength. Charles Hamilton Smith

Charles Hamilton Smith

Lieutenant-Colonel Charles Hamilton Smith was an English artist, naturalist, antiquary, illustrator, soldier and spy.-Military service:...

 wrote that black wolves were generally less aggressive than ordinary kinds, and interbred with dog

Dog

The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...

s more readily.

Asia

Black wolves were occasionally reported in Asia

Asia

Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

. The "Derboun" of the Arabian mountains and southern Syria

Syria

Syria , officially the Syrian Arab Republic , is a country in Western Asia, bordering Lebanon and the Mediterranean Sea to the West, Turkey to the north, Iraq to the east, Jordan to the south, and Israel to the southwest....

 was a small black wolf which apparently was considered by the Arabs to be more closely related to dogs, as they freely ate its flesh like any other game, unlike with regular wolves which had an unpleasant odour. Black wolves in Tibet are known locally as chanko nagpo, and are considered bolder and more aggressive than the pale coloured variety.

North America

Although the black wolves of America were originally given the same bionomial name as those in Europe, Anselme Gaëtan Desmarest

Anselme Gaëtan Desmarest

Anselme Gaëtan Desmarest was a French zoologist and author. He was the son of Nicolas Desmarest and father of Anselme Sébastien Léon Desmarest...

 believed that they were a different species. Historically, the natives of the banks of the Mackenzie River

Mackenzie River

The Mackenzie River is the largest river system in Canada. It flows through a vast, isolated region of forest and tundra entirely within the country's Northwest Territories, although its many tributaries reach into four other Canadian provinces and territories...

, Saskatchewan River

Saskatchewan River

The Saskatchewan River is a major river in Canada, approximately long, flowing roughly eastward across Saskatchewan and Manitoba to empty into Lake Winnipeg...

 and southern Canada apparently never viewed black wolves as a distinct species. In his 1791 book Travels, William Bartram

William Bartram

William Bartram was an American naturalist. The son of Ann and John Bartram, William Bartram and his twin sister Elizabeth were born in Kingsessing, Pennsylvania, near Philadelphia. As a boy, he accompanied his father on many of his travels, to the Catskill Mountains, the New Jersey Pine Barrens,...

 mentioned seeing black wolves among the few red wolf populations he saw in Florida

Florida

Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

. He stated that they were "perfectly black", except the females which were described as having a white spot on the breast. Bartram also described a "black wolf-dog of the Florida Indians

Seminole

The Seminole are a Native American people originally of Florida, who now reside primarily in that state and Oklahoma. The Seminole nation emerged in a process of ethnogenesis out of groups of Native Americans, most significantly Creeks from what is now Georgia and Alabama, who settled in Florida in...

" which was identical to the local wolves, save for the fact that it could bark

Bark (dog)

A bark is a noise most commonly produced by dogs and puppies. Other animals that make this noise include wolves and quolls. Woof is the most common representation in the English language for this sound...

, and could be trusted around horse

Horse

The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...

s. The fur of a black wolf was once considered by the natives of New England

New England

New England is a region in the northeastern corner of the United States consisting of the six states of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut...

 to be worth over 40 American beaver

American Beaver

The North American Beaver is the only species of beaver in the Americas, native to North America and introduced to South America. In the United States and Canada, where no other species of beaver occurs, it is usually simply referred to as "beaver"...

 skins. A chieftain accepting a gift of black wolf fur was seen as an act of reconciliation. The black wolves of the Southern United States

Southern United States

The Southern United States—commonly referred to as the American South, Dixie, or simply the South—constitutes a large distinctive area in the southeastern and south-central United States...

 were considered a separate species to the northern kind due to differences in colour and morphology, and were named clouded or dusky wolves (Canis nubilus). The dusky wolves occurred in Missouri Territory

Missouri Territory

The Territory of Missouri was an organized incorporated territory of the United States that existed from June 4, 1812 until August 10, 1821, when the southeastern portion of the territory was admitted to the Union as the State of Missouri.-History:...

, and were intermediate in size between common wolves and coyotes. They apparently produced a foul odour. On January 15, 2009, a black male wolf from "Mollie's Pack" in the Yellowstone National Park

Yellowstone National Park

Yellowstone National Park, established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872, is a national park located primarily in the U.S. state of Wyoming, although it also extends into Montana and Idaho...

's Pelican Valley was weighed in at 143 lbs, making it the largest Yellowstone wolf on record.

Genetics and ancestry

Adolph Murie

Adolph Murie

Adolph Murie , the first scientist to study wolves in their natural habitat, was a naturalist, author, and wildlife biologist who pioneered field research on wolves, bears, and other mammals and birds in Arctic and sub-Arctic Alaska...

 was among the first wolf biologists to speculate that the wide color variation in wolves was due to interbreeding with dogs;
In 2008, Dr. Gregory S. Barsh, a professor of genetics and pediatrics at the Stanford University School of Medicine

Stanford University School of Medicine

Stanford University School of Medicine is a leading medical school located at Stanford University Medical Center in Stanford, California. Originally based in San Francisco, California as Cooper Medical College, it is the oldest continuously running medical school in the western United States...

 used molecular genetic techniques to analyze DNA

DNA

Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...

 sequences from 150 wolves, half of them black, in Yellowstone National Park

Yellowstone National Park

Yellowstone National Park, established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872, is a national park located primarily in the U.S. state of Wyoming, although it also extends into Montana and Idaho...

, which covers parts of Wyoming

Wyoming

Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

, Montana

Montana

Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

 and Idaho

Idaho

Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....

. It was discovered that a gene mutation

Mutation

In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...

 responsible for the protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 beta-defensin 3, known as the K locus, is responsible for the black coat color in dogs. After finding that the same mutation was responsible for black wolves in North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 and the Italian

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

 Apennines, he set out to discover the origin of the mutation. Dr. Barsh and his colleagues concluded that the mutation arose in dogs 12,779 to 121,182 years ago, with a preferred date of 46,886 years ago after comparing large sections of wolf, dog and coyote

Coyote

The coyote , also known as the American jackal or the prairie wolf, is a species of canine found throughout North and Central America, ranging from Panama in the south, north through Mexico, the United States and Canada...

 genome

Genome

In modern molecular biology and genetics, the genome is the entirety of an organism's hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. The genome includes both the genes and the non-coding sequences of the DNA/RNA....

s. At the University of California, Los Angeles

University of California, Los Angeles

The University of California, Los Angeles is a public research university located in the Westwood neighborhood of Los Angeles, California, USA. It was founded in 1919 as the "Southern Branch" of the University of California and is the second oldest of the ten campuses...

, 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. Black wolves with recent dog ancestry tend to retain black pigment longer as they age.

Function

Seeing as black colored wolves occur more frequently in forested areas than on the tundra (black coats occur in about 62% of wolves in the forested areas of the Canadian Arctic, compared with about 7% in the icy tundra), melanism was concluded by the researchers to give those wolves an adaptive advantage. The mutation’s purpose has not yet been identified. Dr Barsh ruled out camouflage

Camouflage

Camouflage is a method of concealment that allows an otherwise visible animal, military vehicle, or other object to remain unnoticed, by blending with its environment. Examples include a leopard's spotted coat, the battledress of a modern soldier and a leaf-mimic butterfly...

, as wolves have few natural predators, and there is no evidence that a black coat color leads to any increase in hunting success rates. Dr. Barsh observed that beta-defensin is involved in providing immunity to viral

Virus

A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...

 and bacteria

Bacteria

Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...

l skin infection

Skin infection

A skin infection is an infection of the skin. Infection of the skin is distinguished from dermatitis, which is inflammation of the skin, but a skin infection can result in skin inflammation...

s, which might be more common in forested, warmer environments. It has been suggested that the mutation's association with forested habitats means that the prevalence of melanism should increase as forests expand northward. As human hair, dark fur is dominant in wolves. A mating between a black and a gray wolf resulted in ten pups with dark fur out of a total of fourteen.

Distribution

Black wolves rarely occur in Europe and Asia, where interactions with domestic dogs has been reduced over the past thousand years due to the depletion of wild wolf populations. They have occasionally appeared, as wolf-dog hybrids are known in Russia as "black wolves", and currently, 20–25% of Italy's wolf population is composed of black animals. They are more common in North America; about half of the wolves in the reintroduced wolf population in Wyoming's Yellowstone National Park are black. Like Pyrenees Wolves, Black wolves do not live in France. In southern Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 and Minnesota

Minnesota

Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...

the black phase is more common than the white, though grey coloured wolves predominate.