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The wolf (''Canis lupus''; : wolves), also known as the gray wolf or grey wolf, is a large canine native to
Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...
and
North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
. 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 Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...
member of the family
Canidae Canidae (; from Latin, ''canis'', "dog") 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 th ...
. It is also distinguished from other ''
Canis ''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 den ...
'' 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 The coyote (''Canis latrans'') is a species of canis, 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 ecologica ...
and the
golden jackal The golden jackal (''Canis aureus''), also called common jackal, is a wolf-like canid that is native to Southeast Europe, Southwest Asia, South Asia, and regions of Southeast Asia. The golden jackal's coat varies in color from a pale creamy y ...
, 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. Of all members of the
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''Canis'', the wolf is most specialized for
cooperative A cooperative (also known as co-operative, co-op, or coop) is "an autonomous association of persons united voluntarily to meet their common economic, social and cultural needs and aspirations through a jointly owned and democratically-control ...
game hunting Trophy hunting is a form of hunting for field sports, sport in which parts of the hunted wild animals are kept and displayed as trophies. The animal being targeted, known as the "game (hunting), game", is typically a mature male specimen from a p ...
as demonstrated by its physical adaptations to tackling large prey, its more
social nature Social Nature is the core concept of a geographical work on the social construction of nature, entitled ''Social nature: theory, practice and politics'', which has been published by Noel Castree and Bruce Braun in 2001. It says that the concept of ...
, and its highly advanced expressive behaviour including individual or group
howling Howling is a vocal form of animal communication seen in most canines, particularly wolves, coyotes, foxes, and dogs, as well as cats and some species of monkeys. Howls are generally lengthy sustained sounds, loud and audible over long distances, ...
. It travels in
nuclear families A nuclear family, elementary family, cereal-packet family or conjugal family is a family group consisting of parents and their children (one or more), typically living in one home residence. It is in contrast to a single-parent family, the larger ...
consisting of a
mated pair Breeding pair is a pair of animals which cooperate over time to produce offspring with some form of a bond between the individuals.Gaston, A. J.The evolution of group territorial behavior and cooperative breeding" The American Naturalist 112.988 ...
accompanied by their offspring. Offspring may leave to form their own packs on the onset of sexual maturity and in response to competition for food within the pack. Wolves are also
territorial A territory is an area of land, sea, or space, particularly belonging or connected to a country, person, or animal. In international politics, a territory is usually either the total area from which a state may extract power resources or a ...
and fights over territory are among the principal causes of wolf mortality. The wolf is mainly a
carnivore A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...
and feeds on large wild
hooved mammal Ungulates ( ) are members of the diverse clade Ungulata which primarily consists of large mammals with hooves. These include odd-toed ungulates such as horses, rhinoceroses, and tapirs; and even-toed ungulates such as cattle, pigs, giraffes, ...
s as well as smaller animals, livestock,
carrion Carrion () is the decaying flesh of dead animals, including human flesh. Overview Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures, c ...
, and garbage. Single wolves or mated pairs typically have higher success rates in hunting than do large packs.
Pathogen In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ ...
s and parasites, notably
rabies virus Rabies virus, scientific name ''Rabies lyssavirus'', is a neurotropic virus that causes rabies in humans and animals. Rabies transmission can occur through the saliva of animals and less commonly through contact with human saliva. ''Rabies lyss ...
, may infect wolves. The global wild wolf population was estimated to be 300,000 in 2003 and is considered to be of
Least Concern A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...
by the
International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
(IUCN). Wolves have a long history of interactions with humans, having been despised and hunted in most
pastoral A pastoral lifestyle is that of shepherds herding livestock around open areas of land according to seasons and the changing availability of water and pasture. It lends its name to a genre of literature, art, and music (pastorale) that depicts ...
communities because of their attacks on livestock, while conversely being respected in some agrarian and
hunter-gatherer A traditional hunter-gatherer or forager is a human living an ancestrally derived lifestyle in which most or all food is obtained by foraging, that is, by gathering food from local sources, especially edible wild plants but also insects, fungi, ...
societies. The wolf is also considered the ancestor of the
domestic dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is Domestication of the dog, derived from the extinct Pleistocene wolf, and the modern wolf is the dog's n ...
. Although the fear of wolves exists in many human societies, the majority of recorded attacks on people have been attributed to animals suffering from
rabies Rabies is a viral disease that causes encephalitis in humans and other mammals. Early symptoms can include fever and tingling at the site of exposure. These symptoms are followed by one or more of the following symptoms: nausea, vomiting, vi ...
.
Wolf attack Wolf attacks are injuries to humans or their property by any subspecies of wolf. Their frequency varies with geographical location and historical period, but overall gray wolf attacks are rare. Wolves today tend to live mostly far from people o ...
s on humans are rare because wolves are relatively few, live away from people, and have developed a fear of humans because of their experiences with hunters, farmers, ranchers, and shepherds.


Etymology

The English "wolf" stems from the
Old English Old English (, ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlement of Britain, Anglo ...
, which is itself thought to be derived from the
Proto-Germanic Proto-Germanic (abbreviated PGmc; also called Common Germanic) is the reconstructed proto-language of the Germanic branch of the Indo-European languages. Proto-Germanic eventually developed from pre-Proto-Germanic into three Germanic branc ...
. The
Proto-Indo-European root The root (linguistics), roots of the reconstructed Proto-Indo-European language (PIE) are basic parts of words that carry a lexical (semiotics), lexical meaning, so-called morphemes. PIE roots usually have verbal meaning like "to eat" or "to run ...
*' may also be the source of the
Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
word for the animal ''lupus'' (*'). The name "gray wolf" refers to the grayish colour of the species. Since pre-Christian times,
Germanic peoples The Germanic peoples were historical groups of people that once occupied Central Europe and Scandinavia during antiquity and into the early Middle Ages. Since the 19th century, they have traditionally been defined by the use of ancient and ear ...
such as the
Anglo-Saxon The Anglo-Saxons were a Cultural identity, cultural group who inhabited England in the Early Middle Ages. They traced their origins to settlers who came to Britain from mainland Europe in the 5th century. However, the ethnogenesis of the Anglo- ...
s took on ''wulf'' as a
prefix A prefix is an affix which is placed before the Word stem, stem of a word. Adding it to the beginning of one word changes it into another word. For example, when the prefix ''un-'' is added to the word ''happy'', it creates the word ''unhappy'' ...
or
suffix In linguistics, a suffix is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns, adjectives, and verb endings, which form the conjugation of verbs. Suffixes can carry ...
in their names. Examples include Wulfhere ("Wolf Army"), Cynewulf ("Royal Wolf"), Cēnwulf ("Bold Wolf"), Wulfheard ("Wolf-hard"), Earnwulf ("Eagle Wolf"), Wulfstān ("Wolf Stone") Æðelwulf ("Noble Wolf"), Wolfhroc ("Wolf-Frock"), Wolfhetan ("Wolf Hide"), Scrutolf ("Garb Wolf"), Wolfgang ("Wolf Gait") and Wolfdregil ("Wolf Runner").


Taxonomy

In 1758, the Swedish botanist and zoologist
Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...
published in his ''
Systema Naturae ' (originally in Latin written ' with the ligature æ) is one of the major works of the Swedish botanist, zoologist and physician Carl Linnaeus (1707–1778) and introduced the Linnaean taxonomy. Although the system, now known as binomial nomen ...
'' the
binomial nomenclature In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...
. ''
Canis ''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 den ...
'' is the Latin word meaning "
dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...
", and under this
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
he listed the doglike carnivores including domestic dogs, wolves, and
jackal Jackals are medium-sized canids native to Africa and Eurasia. While the word "jackal" has historically been used for many canines of the subtribe canina, in modern use it most commonly refers to three species: the closely related black-backed ...
s. He classified the domestic dog as ''Canis familiaris'', and the wolf as ''Canis lupus''. Linnaeus considered the dog to be a separate species from the wolf because of its "cauda recurvata" (upturning tail) which is not found in any other
canid Canidae (; from Latin, ''canis'', "dog") 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 ...
.


Subspecies

In the third edition of ''
Mammal Species of the World ''Mammal Species of the World: A Taxonomic and Geographic Reference'' is a standard reference work in mammalogy giving descriptions and bibliographic data for the known species of mammals. It is now in its third edition, published in late 2005, ...
'' published in 2005, the
mammalogist In zoology, mammalogy is the study of mammals – a class of vertebrates with characteristics such as homeothermic metabolism, fur, four-chambered hearts, and complex nervous system In biology, the nervous system is the highly complex part o ...
W. Christopher Wozencraft Wallace Christopher Wozencraft (1954–2007) was an American zoologist, specialising in smaller carnivorous mammals. He was professor of biology at Bethel College (Indiana), and chaired the committee on carnivorous mammals at the International Union ...
listed under ''C. lupus'' 36 wild subspecies, and proposed two additional subspecies: ''familiaris'' (Linnaeus, 1758) and ''
dingo The dingo (''Canis familiaris'', ''Canis familiaris dingo'', ''Canis dingo'', or ''Canis lupus dingo'') is an ancient (Basal (phylogenetics), basal) lineage of dog found in Australia (continent), Australia. Its taxonomic classification is de ...
'' (Meyer, 1793). Wozencraft included ''hallstromi''—the
New Guinea singing dog The New Guinea singing dog or New Guinea Highland dog is an ancient ( basal) lineage of dog found in the New Guinea Highlands, on the island of New Guinea. Once considered to be a separate species in its own right, under the name ''Canis hallstr ...
—as a
taxonomic synonym The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linnae ...
for the
dingo The dingo (''Canis familiaris'', ''Canis familiaris dingo'', ''Canis dingo'', or ''Canis lupus dingo'') is an ancient (Basal (phylogenetics), basal) lineage of dog found in Australia (continent), Australia. Its taxonomic classification is de ...
. Wozencraft referred to a 1999
mitochondrial DNA Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial D ...
(mtDNA) study as one of the guides in forming his decision, and listed the 38 subspecies of ''C. lupus'' under the biological
common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...
of "wolf", the
nominate subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
being the
Eurasian wolf The Eurasian wolf (''Canis lupus lupus''), also known as the common wolf,Mech, L. David (1981), ''The Wolf: The Ecology and Behaviour of an Endangered Species'', University of Minnesota Press, p. 354, is a subspecies of grey wolf native to Euro ...
(''C. l. lupus'') based on the
type specimen In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...
that Linnaeus studied in Sweden. Studies using paleogenomic techniques reveal that the modern wolf and the dog are
sister taxa In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and t ...
, as modern wolves are not closely related to the population of wolves that was first
domesticated Domestication is a sustained multi-generational relationship in which humans assume a significant degree of control over the reproduction and care of another group of organisms to secure a more predictable supply of resources from that group. A ...
. In 2019, a workshop hosted by the
IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
/Species Survival Commission's Canid Specialist Group considered the New Guinea singing dog and the dingo to be
feral A feral () animal or plant is one that lives in the wild but is descended from domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems and has, in some ...
''Canis familiaris'', and therefore should not be assessed for the
IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...
.


Evolution

The
phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
descent of the extant wolf ''C. lupus'' from '' C. etruscus'' through '' C. mosbachensis'' is widely accepted. The earliest fossils of ''C. lupus'' were found in what was once eastern
Beringia Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72 degrees north latitude in the Chukchi Sea; and on the south by the tip ...
at
Old Crow, Yukon Old Crow is a community in the Canadian territory of Yukon. Located in a periglacial environment, the community is situated on the Porcupine River in the far northern part of the territory. Old Crow is the only Yukon community that cannot be rea ...
, Canada, and at Cripple Creek Sump,
Fairbanks Fairbanks is a home rule city and the borough seat of the Fairbanks North Star Borough in the U.S. state of Alaska. Fairbanks is the largest city in the Interior region of Alaska and the second largest in the state. The 2020 Census put the po ...
, Alaska. The age is not agreed upon but could date to one million years ago. Considerable morphological diversity existed among wolves by the
Late Pleistocene The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth division of ...
. They had more robust skulls and teeth than modern wolves, often with a shortened
snout A snout is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw. In many animals, the structure is called a muzzle, rostrum, or proboscis. The wet furless surface around the nostrils of the nose of many mammals is c ...
, a pronounced development of the
temporalis In anatomy, the temporalis muscle, also known as the temporal muscle, is one of the muscles of mastication (chewing). It is a broad, fan-shaped convergent muscle on each side of the head that fills the temporal fossa, superior to the zygomatic a ...
muscle, and robust
premolar The premolars, also called premolar teeth, or bicuspids, are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant in the permanent set of teeth, making eight premolars total in the mouth ...
s. It is proposed that these features were specialized adaptations for the processing of carcass and bone associated with the hunting and scavenging of
Pleistocene megafauna Pleistocene megafauna is the set of large animals that lived on Earth during the Pleistocene epoch. Pleistocene megafauna became extinct during the Quaternary extinction event resulting in substantial changes to ecosystems globally. The role of hu ...
. Compared with modern wolves, some Pleistocene wolves showed an increase in tooth breakage similar to that seen in the extinct
dire wolf The dire wolf (''Aenocyon dirus'' ) is an extinct canine. It is one of the most famous prehistoric carnivores in North America, along with its extinct competitor ''Smilodon''. The dire wolf lived in the Americas and eastern Asia during the Lat ...
. This suggests they either often processed carcasses, or that they competed with other carnivores and needed to consume their prey quickly. Compared with those found in the modern
spotted hyena The spotted hyena (''Crocuta crocuta''), also known as the laughing hyena, is a hyena species, currently classed as the sole extant member of the genus ''Crocuta'', native to sub-Saharan Africa. It is listed as being of least concern by the IUC ...
, the frequency and location of tooth fractures in these wolves indicates they were habitual bone crackers.
Genomic Genomics is an interdisciplinary field of biology focusing on the structure, function, evolution, mapping, and editing of genomes. A genome is an organism's complete set of DNA, including all of its genes as well as its hierarchical, three-dim ...
studies suggest modern wolves and dogs descend from a common ancestral wolf population that existed 20,000 years ago. A 2021 study found that the
Himalayan wolf The Himalayan wolf (''Canis lupus chanco'') is a canine of debated taxonomy. It is distinguished by its genetic markers, with mitochondrial DNA indicating that it is genetically basal to the Holarctic gray wolf, genetically the same wolf as the ...
and the Indian plains wolf are part of a
lineage Lineage may refer to: Science * Lineage (anthropology), a group that can demonstrate its common descent from an apical ancestor or a direct line of descent from an ancestor * Lineage (evolution), a temporal sequence of individuals, populati ...
that is basal to other wolves and
split Split(s) or The Split may refer to: Places * Split, Croatia, the largest coastal city in Croatia * Split Island, Canada, an island in the Hudson Bay * Split Island, Falkland Islands * Split Island, Fiji, better known as Hạfliua Arts, enterta ...
from them 200,000 years ago. Other wolves appear to have originated in Beringia in an expansion that was driven by the huge ecological changes during the close of the Late Pleistocene. A study in 2016 indicates that a
population bottleneck A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events such as famines, earthquakes, floods, fires, disease, and droughts; or human activities such as specicide, widespread violen ...
was followed by a rapid
radiation In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium. This includes: * ''electromagnetic radiation'', such as radio waves, microwaves, infrared, visi ...
from an ancestral population at a time during, or just after, the
Last Glacial Maximum The Last Glacial Maximum (LGM), also referred to as the Late Glacial Maximum, was the most recent time during the Last Glacial Period that ice sheets were at their greatest extent. Ice sheets covered much of Northern North America, Northern Eur ...
. This implies the original morphologically diverse wolf populations were out-competed and replaced by more modern wolves. A 2016 genomic study suggests that Old World and New World wolves split around 12,500 years ago followed by the
divergence In vector calculus, divergence is a vector operator that operates on a vector field, producing a scalar field giving the quantity of the vector field's source at each point. More technically, the divergence represents the volume density of the ...
of the lineage that led to dogs from other Old World wolves around 11,100–12,300 years ago. An extinct Late Pleistocene wolf may have been the ancestor of the dog, with the dog's similarity to the extant wolf being the result of
genetic admixture Genetic admixture occurs when previously diverged or isolated genetic lineages mix.⅝ Admixture results in the introduction of new genetic lineages into a population. Examples Climatic cycles facilitate genetic admixture in cold periods and gene ...
between the two. The dingo,
Basenji The Basenji ( /bəˈsɛndʒi/) is a breed of hunting dog. It was bred from stock that originated in central Africa. The Fédération Cynologique Internationale places the breed in the Spitz and primitive types. The Basenji produces an unusual y ...
,
Tibetan Mastiff The Tibetan Mastiff ( bo, འདོགས་ཁྱི, THL: , Wylie: ) * Nepali: * Mongolian: * Hindi/Garhwali/ Kumaoni: * Kashmiri: * Ladakhi: * Dzongkha: is a large size Tibetan dog breed. Its double coat is medium to long, subject ...
and Chinese indigenous breeds are basal members of the domestic dog clade. The divergence time for wolves in Europe, the Middle East, and Asia is estimated to be fairly recent at around 1,600 years ago. Among New World wolves, the
Mexican wolf The Mexican wolf (''Canis lupus baileyi''), also known as the lobo,; nah, Cuetlāchcoyōtl is a subspecies of gray wolf native to southeastern Arizona and southern New Mexico in the United States, and northern Mexico; it also previously range ...
diverged around 5,400 years ago.


Admixture with other canids

In the distant past, there has been
gene flow In population genetics, gene flow (also known as gene migration or geneflow and allele flow) is the transfer of genetic material from one population to another. If the rate of gene flow is high enough, then two populations will have equivalent a ...
between African wolves,
golden jackal The golden jackal (''Canis aureus''), also called common jackal, is a wolf-like canid that is native to Southeast Europe, Southwest Asia, South Asia, and regions of Southeast Asia. The golden jackal's coat varies in color from a pale creamy y ...
s, and gray wolves. The African wolf is a descendant of a genetically admixed canid of 72% wolf and 28% Ethiopian wolf ancestry. One African wolf from the Egyptian
Sinai Peninsula The Sinai Peninsula, or simply Sinai (now usually ) (, , cop, Ⲥⲓⲛⲁ), is a peninsula in Egypt, and the only part of the country located in Asia. It is between the Mediterranean Sea to the north and the Red Sea to the south, and is a l ...
shows admixture with Middle Eastern gray wolves and dogs. There is evidence of gene flow between golden jackals and Middle Eastern wolves, less so with European and Asian wolves, and least with North American wolves. This indicates the golden jackal ancestry found in North American wolves may have occurred before the divergence of the Eurasian and North American wolves. The common ancestor of the coyote and the wolf has admixed with a
ghost population A ghost population is a population that has been inferred through using statistical techniques. Population studies In 2004, it was proposed that maximum likelihood or Bayesian approaches that estimate the migration rates and population sizes using ...
of an extinct unidentified canid. This canid is genetically close to the
dhole The dhole (''Cuon alpinus''; ) is a canid native to Central, South, East and Southeast Asia. Other English names for the species include Asian wild dog, Asiatic wild dog, Indian wild dog, whistling dog, red dog, red wolf, and mountain wolf. It ...
and evolved after the divergence of the
African hunting dog The African wild dog (''Lycaon pictus''), also called the painted dog or Cape hunting dog, is a wild canine which is a native species to sub-Saharan Africa. It is the largest wild canine in Africa, and the only extant member of the genus '' L ...
from the other canid species. The basal position of the
coyote The coyote (''Canis latrans'') is a species of canis, 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 ecologica ...
compared to the wolf is proposed to be due to the coyote retaining more of the mitochondrial genome of this unidentified canid. Similarly, a museum specimen of a wolf from southern China collected in 1963 showed a genome that was 12–14% admixed from this unknown canid. In North America, most coyotes and wolves show varying degrees of past
genetic admixture Genetic admixture occurs when previously diverged or isolated genetic lineages mix.⅝ Admixture results in the introduction of new genetic lineages into a population. Examples Climatic cycles facilitate genetic admixture in cold periods and gene ...
. In more recent times, some male Italian wolves originated from dog ancestry, which indicates female wolves will breed with male dogs in the wild. In the
Caucasus Mountains The Caucasus Mountains, : pronounced * hy, Կովկասյան լեռներ, : pronounced * az, Qafqaz dağları, pronounced * rus, Кавка́зские го́ры, Kavkázskiye góry, kɐfˈkasːkʲɪje ˈɡorɨ * tr, Kafkas Dağla ...
, ten percent of dogs including
livestock guardian dog A livestock guardian dog (LGD) is a dog type bred for the purpose of protecting livestock from predators. Livestock guardian dogs stay with the group of animals they protect as a full-time member of the flock or herd. Their ability to guard t ...
s, are first generation hybrids. Although mating between golden jackals and wolves has never been observed, evidence of jackal-wolf hybridization was discovered through mitochondrial DNA analysis of jackals living in the Caucasus Mountains and in Bulgaria. In 2021, a genetic study found that the dog's similarity to the extant gray wolf was the result of substantial dog-into-wolf
gene flow In population genetics, gene flow (also known as gene migration or geneflow and allele flow) is the transfer of genetic material from one population to another. If the rate of gene flow is high enough, then two populations will have equivalent a ...
, with almost negligible wolf-into-dog gene flow since the dog's domestication. Some gray wolves were related to all ancient and modern dogs.


Description

The wolf is the largest extant member of the
Canidae Canidae (; from Latin, ''canis'', "dog") 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 th ...
family, and is further distinguished from coyotes and jackals by a broader snout, shorter ears, a shorter torso and a longer tail. It is slender and powerfully built, with a large, deeply descending
rib cage The rib cage, as an enclosure that comprises the ribs, vertebral column and sternum in the thorax of most vertebrates, protects vital organs such as the heart, lungs and great vessels. The sternum, together known as the thoracic cage, is a semi- ...
, a sloping back, and a heavily muscled neck. The wolf's legs are moderately longer than those of other canids, which enables the animal to move swiftly, and to overcome the deep snow that covers most of its geographical range in winter. The ears are relatively small and triangular. The wolf's head is large and heavy, with a wide forehead, strong jaws and a long, blunt muzzle. The skull is in length and in width. The teeth are heavy and large, making them better suited to crushing bone than those of other canids. They are not as specialized as those found in
hyena Hyenas, or hyaenas (from Ancient Greek , ), are feliform carnivoran mammals of the family Hyaenidae . With only four extant species (each in its own genus), it is the fifth-smallest family in the Carnivora and one of the smallest in the clas ...
s though. Its
molars The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone to ...
have a flat chewing surface, but not to the same extent as the coyote, whose diet contains more vegetable matter. Females tend to have narrower muzzles and foreheads, thinner necks, slightly shorter legs, and less massive shoulders than males. Adult wolves measure in length and at shoulder height. The tail measures in length, the ears in height, and the hind feet are . The size and weight of the modern wolf increases proportionally with latitude in accord with
Bergmann's rule Bergmann's rule is an ecogeographical rule that states that within a broadly distributed taxonomic clade, populations and species of larger size are found in colder environments, while populations and species of smaller size are found in warmer ...
. The mean body mass of the wolf is , the smallest specimen recorded at and the largest at . On average, European wolves weigh , North American wolves , and Indian and Arabian wolves . Females in any given wolf population typically weigh less than males. Wolves weighing over are uncommon, though exceptionally large individuals have been recorded in Alaska and Canada. In central Russia, exceptionally large males can reach a weight of .


Pelage

The wolf has very dense and fluffy winter fur, with a short undercoat and long, coarse
guard hair Guard hair or overhair is the outer layer of hair of most mammals, which overlay the fur. Guard hairs are long and coarse and protect the rest of the pelage (fur) from abrasion and frequently from moisture. They are visible on the surface of the fu ...
s. Most of the undercoat and some guard hairs are shed in spring and grow back in autumn. The longest hairs occur on the back, particularly on the front quarters and neck. Especially long hairs grow on the shoulders and almost form a crest on the upper part of the neck. The hairs on the cheeks are elongated and form tufts. The ears are covered in short hairs and project from the fur. Short, elastic and closely adjacent hairs are present on the limbs from the
elbow The elbow is the region between the arm and the forearm that surrounds the elbow joint. The elbow includes prominent landmarks such as the olecranon, the cubital fossa (also called the chelidon, or the elbow pit), and the lateral and the media ...
s down to the
calcaneal tendon The Achilles tendon or heel cord, also known as the calcaneal tendon, is a tendon at the back of the lower leg, and is the thickest in the human body. It serves to attach the plantaris, gastrocnemius (calf) and soleus muscles to the calcaneus (h ...
s. The winter fur is highly resistant to the cold. Wolves in northern climates can rest comfortably in open areas at by placing their muzzles between the rear legs and covering their faces with their tail. Wolf fur provides better insulation than dog fur and does not collect ice when warm breath is condensed against it. In cold climates, the wolf can reduce the flow of blood near its skin to conserve body heat. The warmth of the foot pads is regulated independently from the rest of the body and is maintained at just above tissue-freezing point where the pads come in contact with ice and snow. In warm climates, the fur is coarser and scarcer than in northern wolves. Female wolves tend to have smoother furred limbs than males and generally develop the smoothest overall coats as they age. Older wolves generally have more white hairs on the tip of the tail, along the nose, and on the forehead. Winter fur is retained longest by lactating females, although with some hair loss around their teats. Hair length on the middle of the back is , and the guard hairs on the shoulders generally do not exceed , but can reach . A wolf's coat colour is determined by its guard hairs. Wolves usually have some hairs that are white, brown, gray and black. The coat of the Eurasian wolf is a mixture of
ochre Ochre ( ; , ), or ocher in American English, is a natural clay earth pigment, a mixture of ferric oxide and varying amounts of clay and sand. It ranges in colour from yellow to deep orange or brown. It is also the name of the colours produced ...
ous (yellow to orange) and
rusty Rusty may refer to something covered with rust or with a rust (color). Rusty is also a nickname for people who have red hair, have a rust-hued skin tone, or have the given name Russell. Rusty may also refer to: People *Rusty Anderson (born 1959 ...
ochreous (orange/red/brown) colours with light gray. The muzzle is pale ochreous gray, and the area of the lips, cheeks, chin, and throat is white. The top of the head, forehead, under and between the eyes, and between the eyes and ears is gray with a reddish film. The neck is ochreous. Long, black tips on the hairs along the back form a broad stripe, with black hair tips on the shoulders, upper chest and rear of the body. The sides of the body, tail, and outer limbs are a pale dirty ochreous colour, while the inner sides of the limbs, belly, and groin are white. Apart from those wolves which are pure white or black, these tones vary little across geographical areas, although the patterns of these colours vary between individuals. In North America, the coat colours of wolves follow
Gloger's rule Gloger's rule is an ecogeographical rule which states that within a species of endotherms, more heavily pigmented forms tend to be found in more humid environments, e.g. near the equator. It was named after the zoologist Constantin Wilhelm Lambert ...
, wolves in the Canadian arctic being white and those in southern Canada, the U.S., and Mexico being predominantly gray. In some areas of the
Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico in ...
of Alberta and British Columbia, the coat colour is predominantly black, some being blue-gray and some with silver and black. Differences in coat colour between sexes is absent in Eurasia; females tend to have redder tones in North America. Black-coloured wolves in North America acquired their colour from wolf-dog admixture after the first arrival of dogs across the Bering Strait 12,000 to 14,000 years ago. Research into the inheritance of white colour from dogs into wolves has yet to be undertaken.


Ecology


Distribution and habitat

Wolves occur across Eurasia and North America. However, deliberate human persecution because of livestock predation and fear of attacks on humans has reduced the wolf's range to about one-third of its historic range; the wolf is now
extirpated Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...
(locally extinct) from much of its range in Western Europe, the United States and Mexico, and completely in Ireland, the United Kingdom, and Japan. In modern times, the wolf occurs mostly in wilderness and remote areas. The wolf can be found between sea level and . Wolves live in forests, inland
wetland A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...
s,
shrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It m ...
s,
grassland A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
s (including Arctic
tundra In physical geography, tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term ''tundra'' comes through Russian (') from the Kildin Sámi word (') meaning "uplands", "treeless moun ...
),
pasture Pasture (from the Latin ''pastus'', past participle of ''pascere'', "to feed") is land used for grazing. Pasture lands in the narrow sense are enclosed tracts of farmland, grazed by domesticated livestock, such as horses, cattle, sheep, or swine ...
s, deserts, and rocky peaks on mountains. Habitat use by wolves depends on the abundance of prey, snow conditions, livestock densities, road densities, human presence and
topography Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the land forms and features themselves, or a description or depiction in maps. Topography is a field of geoscience and planetary sci ...
.


Diet

Like all land mammals that are
pack hunter A pack hunter or social predator is a predatory animal which hunts its prey by working together with other members of its species. Normally animals hunting in this way are closely related, and with the exceptions of chimpanzees where only male ...
s, the wolf feeds predominantly on wild herbivorous
hoofed mammals Ungulates ( ) are members of the diverse clade Ungulata which primarily consists of large mammals with hooves. These include odd-toed ungulates such as horses, rhinoceroses, and tapirs; and even-toed ungulates such as cattle, pigs, giraffes, cam ...
that can be divided into large size and medium size , and have a body mass similar to that of the combined mass of the pack members. The wolf specializes in preying on the vulnerable individuals of large prey, with a pack of 15 able to bring down an adult
moose The moose (in North America) or elk (in Eurasia) (''Alces alces'') is a member of the New World deer subfamily and is the only species in the genus ''Alces''. It is the largest and heaviest extant species in the deer family. Most adult mal ...
. The variation in diet between wolves living on different continents is based on the variety of hoofed mammals and of available smaller and domesticated prey. In North America, the wolf's diet is dominated by wild large hoofed mammals (ungulates) and medium-sized mammals. In Asia and Europe, their diet is dominated by wild medium-sized hoofed mammals and domestic species. The wolf depends on wild species, and if these are not readily available, as in Asia, the wolf is more reliant on domestic species. Across Eurasia, wolves prey mostly on
moose The moose (in North America) or elk (in Eurasia) (''Alces alces'') is a member of the New World deer subfamily and is the only species in the genus ''Alces''. It is the largest and heaviest extant species in the deer family. Most adult mal ...
,
red deer The red deer (''Cervus elaphus'') is one of the largest deer species. A male red deer is called a stag or hart, and a female is called a hind. The red deer inhabits most of Europe, the Caucasus Mountains region, Anatolia, Iran, and parts of wes ...
,
roe deer The roe deer (''Capreolus capreolus''), also known as the roe, western roe deer, or European roe, is a species of deer. The male of the species is sometimes referred to as a roebuck. The roe is a small deer, reddish and grey-brown, and well-adapt ...
and
wild boar The wild boar (''Sus scrofa''), also known as the wild swine, common wild pig, Eurasian wild pig, or simply wild pig, is a suid native to much of Eurasia and North Africa, and has been introduced to the Americas and Oceania. The species is ...
. In North America, important range-wide prey are
elk The elk (''Cervus canadensis''), also known as the wapiti, is one of the largest species within the deer family, Cervidae, and one of the largest terrestrial mammals in its native range of North America and Central and East Asia. The common ...
, moose,
caribou Reindeer (in North American English, known as caribou if wild and ''reindeer'' if domesticated) are deer in the genus ''Rangifer''. For the last few decades, reindeer were assigned to one species, ''Rangifer tarandus'', with about 10 subspe ...
,
white-tailed deer The white-tailed deer (''Odocoileus virginianus''), also known as the whitetail or Virginia deer, is a medium-sized deer native to North America, Central America, and South America as far south as Peru and Bolivia. It has also been introduced t ...
and
mule deer The mule deer (''Odocoileus hemionus'') is a deer indigenous to western North America; it is named for its ears, which are large like those of the mule. Two subspecies of mule deer are grouped into the black-tailed deer. Unlike the related whit ...
. They also prey on
bison Bison are large bovines in the genus ''Bison'' (Greek: "wild ox" (bison)) within the tribe Bovini. Two extant and numerous extinct species are recognised. Of the two surviving species, the American bison, ''B. bison'', found only in North Ame ...
and
muskoxen The muskox (''Ovibos moschatus'', in Latin "musky sheep-ox"), also spelled musk ox and musk-ox, plural muskoxen or musk oxen (in iu, ᐅᒥᖕᒪᒃ, umingmak; in Woods Cree: ), is a hoofed mammal of the family Bovidae. Native to the Arctic, i ...
. Wolves can digest their meal in a few hours and can feed several times in one day, making quick use of large quantities of meat. A well-fed wolf stores
fat In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food. The term often refers spec ...
under the skin, around the heart, intestines, kidneys, and bone marrow, particularly during the autumn and winter. Nonetheless, wolves are not fussy eaters. Smaller-sized animals that may supplement their diet include
rodent Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are na ...
s,
rabbit Rabbits, also known as bunnies or bunny rabbits, are small mammals in the family Leporidae (which also contains the hares) of the order Lagomorpha (which also contains the pikas). ''Oryctolagus cuniculus'' includes the European rabbit speci ...
s,
hare Hares and jackrabbits are mammals belonging to the genus ''Lepus''. They are herbivores, and live solitarily or in pairs. They nest in slight depressions called forms, and their young are able to fend for themselves shortly after birth. The ge ...
s,
insectivore A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores wer ...
s and smaller carnivores. They frequently eat
waterfowl Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which in ...
and their eggs. When such foods are insufficient, they prey on
lizard Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt ...
s,
snake Snakes are elongated, Limbless vertebrate, limbless, carnivore, carnivorous reptiles of the suborder Serpentes . Like all other Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), scales. Ma ...
s,
frog A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...
s, and large insects when available. Wolves in northern Minnesota prey on
northern pike The northern pike (''Esox lucius'') is a species of carnivorous fish of the genus '' Esox'' (the pikes). They are typical of brackish and fresh waters of the Northern Hemisphere (''i.e.'' holarctic in distribution). They are known simply as a ...
in freshwater streams. The diet of coastal wolves in Alaska includes 20%
salmon Salmon () is the common name for several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the family (biology), family Salmonidae, which are native to tributary, tributaries of the ...
, while those of coastal wolves in British Columbia includes 25% marine sources, and those on the nearby islands 75%. In Europe, wolves eat apples, pears,
figs The fig is the edible fruit of ''Ficus carica'', a species of small tree in the flowering plant family Moraceae. Native to the Mediterranean and western Asia, it has been cultivated since ancient times and is now widely grown throughout the world ...
, melons,
berries A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, raspb ...
and
cherries A cherry is the fruit of many plants of the genus ''Prunus'', and is a fleshy drupe (stone fruit). Commercial cherries are obtained from cultivars of several species, such as the sweet ''Prunus avium'' and the sour ''Prunus cerasus''. The nam ...
. In North America, wolves eat
blueberries Blueberries are a widely distributed and widespread group of perennial flowering plants with blue or purple berries. They are classified in the section ''Cyanococcus'' within the genus ''Vaccinium''. ''Vaccinium'' also includes cranberries, bi ...
and
raspberries The raspberry is the edible fruit of a multitude of plant species in the genus ''Rubus'' of the rose family, most of which are in the subgenus '' Idaeobatus''. The name also applies to these plants themselves. Raspberries are perennial with w ...
. Wolves also eat grass, which may provide some vitamins, but is most likely used mainly to induce vomiting to rid themselves of intestinal parasites or long guard hairs. They are known to eat the berries of mountain-ash,
lily of the valley Lily of the valley (''Convallaria majalis'' (), sometimes written lily-of-the-valley, is a woodland flowering plant with sweetly scented, pendent, bell-shaped white flowers borne in sprays in spring. It is native throughout the cool temperate No ...
,
bilberries Bilberries (), or sometimes European blueberries, are a primarily Eurasian species of low-growing shrubs in the genus ''Vaccinium'' (family Ericaceae), bearing edible, dark blue berries. The species most often referred to is ''Vaccinium myrtillu ...
, cowberries, European black nightshade, grain crops, and the shoots of reeds. In times of scarcity, wolves will readily eat
carrion Carrion () is the decaying flesh of dead animals, including human flesh. Overview Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures, c ...
. In Eurasian areas with dense human activity, many wolf populations are forced to subsist largely on livestock and garbage. Prey in North America continue to occupy suitable habitats with low human density, the wolves eating livestock and garbage only in dire circumstances.
Cannibalism Cannibalism is the act of consuming another individual of the same species as food. Cannibalism is a common ecological interaction in the animal kingdom and has been recorded in more than 1,500 species. Human cannibalism is well documented, b ...
is not uncommon in wolves during harsh winters, when packs often attack weak or injured wolves and may eat the bodies of dead pack members.


Interactions with other predators

Wolves typically dominate other canid species in areas where they both occur. In North America, incidents of wolves killing coyotes are common, particularly in winter, when coyotes feed on wolf kills. Wolves may attack coyote den sites, digging out and killing their pups, though rarely eating them. There are no records of coyotes killing wolves, though coyotes may chase wolves if they outnumber them. According to a press release by the U.S. Department of Agriculture in 1921, the infamous
Custer Wolf The Custer Wolf was a North American gray wolf who was held responsible for extensive damage to ranchers' livestock in the area surrounding Custer, South Dakota, between 1911 and 1920, with the damage estimated at $25,000. The wolf was shot by a ...
relied on coyotes to accompany him and warn him of danger. Though they fed from his kills, he never allowed them to approach him. Interactions have been observed in Eurasia between wolves and golden jackals, the latter's numbers being comparatively small in areas with high wolf densities. Wolves also kill
red Red is the color at the long wavelength end of the visible spectrum of light, next to orange and opposite violet. It has a dominant wavelength of approximately 625–740 nanometres. It is a primary color in the RGB color model and a secondar ...
,
Arctic The Arctic ( or ) is a polar regions of Earth, polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenla ...
and
corsac fox The corsac fox (''Vulpes corsac''), also known simply as a corsac, is a medium-sized fox found in steppes, semi-deserts and deserts in Central Asia, ranging into Mongolia and northern China. Since 2004, it has been classified as ''least concern ...
es, usually in disputes over carcasses, sometimes eating them.
Brown bear The brown bear (''Ursus arctos'') is a large bear species found across Eurasia and North America. In North America, the populations of brown bears are called grizzly bears, while the subspecies that inhabits the Kodiak Islands of Alaska is kno ...
s typically dominate wolf packs in disputes over carcasses, while wolf packs mostly prevail against bears when defending their den sites. Both species kill each other's young. Wolves eat the brown bears they kill, while brown bears seem to eat only young wolves. Wolf interactions with
American black bear The American black bear (''Ursus americanus''), also called simply a black bear or sometimes a baribal, is a medium-sized bear endemic to North America. It is the continent's smallest and most widely distributed bear species. American black bear ...
s are much rarer because of differences in habitat preferences. Wolves have been recorded on numerous occasions actively seeking out American black bears in their dens and killing them without eating them. Unlike brown bears, American black bears frequently lose against wolves in disputes over kills. Wolves also dominate and sometimes kill
wolverine The wolverine (), (''Gulo gulo''; ''Gulo'' is Latin for "gluttony, glutton"), also referred to as the glutton, carcajou, or quickhatch (from East Cree, ''kwiihkwahaacheew''), is the largest land-dwelling species of the family Mustelidae. It is ...
s, and will chase off those that attempt to scavenge from their kills. Wolverines escape from wolves in caves or up trees. Wolves may interact and compete with
felids Felidae () is the family of mammals in the order Carnivora colloquially referred to as cats, and constitutes a clade. A member of this family is also called a felid (). The term "cat" refers both to felids in general and specifically to the do ...
, such as the
Eurasian lynx The Eurasian lynx (''Lynx lynx'') is a medium-sized wild cat widely distributed from Northern, Central and Eastern Europe to Central Asia and Siberia, the Tibetan Plateau and the Himalayas. It inhabits temperate and boreal forests up to an eleva ...
, which may feed on smaller prey where wolves are present and may be suppressed by large wolf populations. Wolves encounter
cougar The cougar (''Puma concolor'') is a large Felidae, cat native to the Americas. Its Species distribution, range spans from the Canadian Yukon to the southern Andes in South America and is the most widespread of any large wild terrestrial mamm ...
s along portions of the Rocky Mountains and adjacent mountain ranges. Wolves and cougars typically avoid encountering each other by hunting at different elevations for different prey (
niche partitioning In ecology, niche differentiation (also known as niche segregation, niche separation and niche partitioning) refers to the process by which competing species use the environment differently in a way that helps them to coexist. The competitive excl ...
). In winter, when snow accumulation forces their prey into valleys, interactions between the two species become more likely. Wolves in packs usually dominate cougars and can steal their kills or even kill them, while one-to-one encounters tend to be dominated by the cat. There are several documented cases of cougars killing wolves. Wolves more broadly affect cougar population dynamics and distribution by dominating territory and prey opportunities and disrupting the feline's behaviour. Wolf and
Siberian tiger The Siberian tiger or Amur tiger is a population of the tiger subspecies ''Panthera tigris tigris'' native to the Russian Far East, Northeast China and possibly North Korea. It once ranged throughout the Korean Peninsula, but currently inhabit ...
interactions are well-documented in the
Russian Far East The Russian Far East (russian: Дальний Восток России, r=Dal'niy Vostok Rossii, p=ˈdalʲnʲɪj vɐˈstok rɐˈsʲiɪ) is a region in Northeast Asia. It is the easternmost part of Russia and the Asian continent; and is admini ...
, where tigers significantly depress wolf numbers, sometimes to the point of localized extinction. Only human depletion of tiger numbers appears to protect wolves from
competitive exclusion In ecology, the competitive exclusion principle, sometimes referred to as Gause's law, is a proposition that two species which compete for the same limited resource cannot coexist at constant population values. When one species has even the sligh ...
from them. With perhaps only four proven records of tigers killing wolves, these cases are rare; attacks appear to be competitive rather than predatory in nature. In Israel, Palestine, Central Asia and India wolves may encounter striped hyenas, usually in disputes over carcasses. Striped hyenas feed extensively on wolf-killed carcasses in areas where the two species interact. One-to-one, hyenas dominate wolves, and may prey on them, but wolf packs can drive off single or outnumbered hyenas. There is at least one case in Israel of a hyena associating and cooperating with a wolf pack. It is proposed that the hyena could benefit from the wolves' superior ability to hunt large, agile prey. The wolves could benefit from the hyena's superior sense of smell, to locate and dig out tortoises, to crack open large bones, and to tear open discarded food containers like tin cans.


Behaviour


Social structure

The wolf is a
social animal Sociality is the degree to which individuals in an animal population tend to associate in social groups (gregariousness) and form cooperative societies. Sociality is a survival response to evolutionary pressures. For example, when a mother wasp ...
. Its populations consist of packs and lone wolves, most lone wolves being temporarily alone while they disperse from packs to form their own or join another one. The wolf's basic social unit is the
nuclear family A nuclear family, elementary family, cereal-packet family or conjugal family is a family group consisting of parents and their children (one or more), typically living in one home residence. It is in contrast to a single-parent family, the larger ...
consisting of a
mated pair Breeding pair is a pair of animals which cooperate over time to produce offspring with some form of a bond between the individuals.Gaston, A. J.The evolution of group territorial behavior and cooperative breeding" The American Naturalist 112.988 ...
accompanied by their offspring. The average pack size in North America is eight wolves and in Europe 5.5 wolves. The average pack across Eurasia consists of a family of eight wolves (two adults, juveniles, and yearlings), or sometimes two or three such families, with examples of exceptionally large packs consisting of up to 42 wolves being known.
Cortisol Cortisol is a steroid hormone, in the glucocorticoid class of hormones. When used as a medication, it is known as hydrocortisone. It is produced in many animals, mainly by the ''zona fasciculata'' of the adrenal cortex in the adrenal gland ...
levels in wolves rise significantly when a pack member dies, indicating the presence of stress. During times of prey abundance caused by calving or migration, different wolf packs may join together temporarily. Offspring typically stay in the pack for 10–54 months before dispersing. Triggers for dispersal include the onset of
sexual maturity Sexual maturity is the capability of an organism to reproduce. In humans it might be considered synonymous with adulthood, but here puberty is the name for the process of biological sexual maturation, while adulthood is based on cultural definitio ...
and competition within the pack for food. The distance travelled by dispersing wolves varies widely; some stay in the vicinity of the parental group, while other individuals may travel great distances of upwards of , , and from their natal (birth) packs. A new pack is usually founded by an unrelated dispersing male and female, travelling together in search of an area devoid of other hostile packs. Wolf packs rarely adopt other wolves into their fold and typically kill them. In the rare cases where other wolves are adopted, the adoptee is almost invariably an immature animal of one to three years old, and unlikely to compete for breeding rights with the mated pair. This usually occurs between the months of February and May. Adoptee males may mate with an available pack female and then form their own pack. In some cases, a lone wolf is adopted into a pack to replace a deceased breeder. Wolves are
territorial A territory is an area of land, sea, or space, particularly belonging or connected to a country, person, or animal. In international politics, a territory is usually either the total area from which a state may extract power resources or a ...
and generally establish territories far larger than they require to survive assuring a steady supply of prey. Territory size depends largely on the amount of prey available and the age of the pack's pups. They tend to increase in size in areas with low prey populations, or when the pups reach the age of six months when they have the same nutritional needs as adults. Wolf packs travel constantly in search of prey, covering roughly 9% of their territory per day, on average . The core of their territory is on average where they spend 50% of their time. Prey density tends to be much higher on the territory's periphery. Except out of desperation, wolves tend to avoid hunting on the fringes of their range to avoid fatal confrontations with neighbouring packs. The smallest territory on record was held by a pack of six wolves in northeastern Minnesota, which occupied an estimated , while the largest was held by an Alaskan pack of ten wolves encompassing . Wolf packs are typically settled, and usually leave their accustomed ranges only during severe food shortages. Territorial fights are among the principal causes of wolf mortality, one study concluding that 14–65% of wolf deaths in Minnesota and the
Denali National Park and Preserve Denali National Park and Preserve, formerly known as Mount McKinley National Park, is an American national park and preserve located in Interior Alaska, centered on Denali, the highest mountain in North America. The park and contiguous preserve e ...
were due to other wolves.


Communication

Wolves communicate using vocalizations, body postures, scent, touch, and taste. The phases of the moon have no effect on wolf vocalization, and despite popular belief, wolves do not howl at the moon. Wolves
howl Howl most often refers to: *Howling, an animal vocalization in many canine species *Howl (poem), a 1956 poem by Allen Ginsberg Howl may also refer to: Film * ''The Howl'', a 1970 Italian film * ''Howl'' (2010 film), a 2010 American arthouse b ...
to assemble the pack usually before and after hunts, to pass on an alarm particularly at a den site, to locate each other during a storm, while crossing unfamiliar territory, and to communicate across great distances. Wolf howls can under certain conditions be heard over areas of up to . Other vocalizations include growls,
barks Barks may refer to: * Carl Barks (1901 – 2000) was an American cartoonist, author, and painter * Coleman Barks (b. 1937), an American poet, and former literature faculty at the University of Georgia * Samantha Barks (b. 1990), a Manx actress and ...
and whines. Wolves do not bark as loudly or continuously as dogs do in confrontations, rather barking a few times and then retreating from a perceived danger. Aggressive or self-assertive wolves are characterized by their slow and deliberate movements, high body
posture Posture or posturing may refer to: Medicine * Human position ** Abnormal posturing, in neurotrauma **Spinal posture ** List of human positions * Posturography, in neurology Other uses * Posture (psychology) In humans, posture can provide a s ...
and raised
hackles Hackles are the erectile plumage or hair in the neck area of some birds and mammals. In birds, the hackle is the group of feathers found along the back and side of the neck. The hackles of some types of chicken, particularly roosters, are long, ...
, while submissive ones carry their bodies low, flatten their fur, and lower their ears and tail. Scent marking involves urine, feces, and anal gland scents. This is more effective at advertising territory than howling and is often used in combination with scratch marks. Wolves increase their rate of scent marking when they encounter the marks of wolves from other packs. Lone wolves will rarely mark, but newly bonded pairs will scent mark the most. These marks are generally left every throughout the territory on regular travelways and junctions. Such markers can last for two to three weeks, and are typically placed near rocks, boulders, trees, or the skeletons of large animals. Raised leg
urination Urination, also known as micturition, is the release of urine from the urinary bladder through the urethra to the outside of the body. It is the urinary system's form of excretion. It is also known medically as micturition, voiding, uresis, ...
is considered to be one of the most important forms of scent communication in the wolf, making up 60–80% of all scent marks observed.


Reproduction

Wolves are
monogamous Monogamy ( ) is a form of Dyad (sociology), dyadic Intimate relationship, relationship in which an individual has only one Significant other, partner during their lifetime. Alternately, only one partner at any one time (Monogamy#Serial monogamy, ...
, mated pairs usually remaining together for life. Should one of the pair die, another mate is found quickly. With wolves in the wild, inbreeding does not occur where outbreeding is possible. Wolves become mature at the age of two years and sexually mature from the age of three years. The age of first breeding in wolves depends largely on environmental factors: when food is plentiful, or when wolf populations are heavily managed, wolves can rear pups at younger ages to better exploit abundant resources. Females are capable of producing pups every year, one
litter Litter consists of waste products that have been discarded incorrectly, without consent, at an unsuitable location. Litter can also be used as a verb; to litter means to drop and leave objects, often man-made, such as aluminum cans, paper cups, ...
annually being the average.
Oestrus The estrous cycle (, originally ) is the set of recurring physiological changes that are induced by reproductive hormones in most mammalian therian females. Estrous cycles start after sexual maturity in females and are interrupted by anestrous ...
and rut begin in the second half of winter and lasts for two weeks. Dens are usually constructed for pups during the summer period. When building dens, females make use of natural shelters like fissures in rocks, cliffs overhanging riverbanks and holes thickly covered by vegetation. Sometimes, the den is the appropriated burrow of smaller animals such as foxes, badgers or marmots. An appropriated den is often widened and partly remade. On rare occasions, female wolves dig burrows themselves, which are usually small and short with one to three openings. The den is usually constructed not more than away from a water source. It typically faces southwards where it can be better warmed by sunlight exposure, and the snow can thaw more quickly. Resting places, play areas for the pups, and food remains are commonly found around wolf dens. The odor of urine and rotting food emanating from the denning area often attracts scavenging birds like
magpie Magpies are birds of the Corvidae family. Like other members of their family, they are widely considered to be intelligent creatures. The Eurasian magpie, for instance, is thought to rank among the world's most intelligent creatures, and is one ...
s and
raven A raven is any of several larger-bodied bird species of the genus ''Corvus''. These species do not form a single taxonomic group within the genus. There is no consistent distinction between "crows" and "ravens", common names which are assigned t ...
s. Though they mostly avoid areas within human sight, wolves have been known to nest near domiciles, paved
road A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation. There are many types of ...
s and
railway Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a pre ...
s. During pregnancy, female wolves remain in a den located away from the peripheral zone of their territories, where violent encounters with other packs are less likely to occur. The
gestation period In mammals, pregnancy is the period of reproduction during which a female carries one or more live offspring from implantation in the uterus through gestation. It begins when a fertilized zygote implants in the female's uterus, and ends once it ...
lasts 62–75 days with pups usually being born in the spring months or early summer in very cold places such as on the tundra. Young females give birth to four to five young, and older females from six to eight young and up to 14. Their mortality rate is 60–80%. Newborn wolf pups look similar to
German Shepherd Dog The German Shepherd or Alsatian is a German breed of working dog of medium to large size. The breed was developed by Max von Stephanitz using various traditional German herding dogs from 1899. It was originally bred as a herding dog, for he ...
pups. They are born blind and deaf and are covered in short soft grayish-brown fur. They weigh at birth and begin to see after nine to 12 days. The milk canines erupt after one month. Pups first leave the den after three weeks. At one-and-a-half months of age, they are agile enough to flee from danger. Mother wolves do not leave the den for the first few weeks, relying on the fathers to provide food for them and their young. Pups begin to eat solid food at the age of three to four weeks. They have a fast growth rate during their first four months of life: during this period, a pup's weight can increase nearly 30 times. Wolf pups begin play-fighting at the age of three weeks, though unlike young coyotes and foxes, their bites are gentle and controlled. Actual fights to establish hierarchy usually occur at five to eight weeks of age. This is in contrast to young coyotes and foxes, which may begin fighting even before the onset of play behaviour. By autumn, the pups are mature enough to accompany the adults on hunts for large prey.


Hunting and feeding

Single wolves or mated pairs typically have higher success rates in hunting than do large packs; single wolves have occasionally been observed to kill large prey such as moose,
bison Bison are large bovines in the genus ''Bison'' (Greek: "wild ox" (bison)) within the tribe Bovini. Two extant and numerous extinct species are recognised. Of the two surviving species, the American bison, ''B. bison'', found only in North Ame ...
and
muskox The muskox (''Ovibos moschatus'', in Latin "musky sheep-ox"), also spelled musk ox and musk-ox, plural muskoxen or musk oxen (in iu, ᐅᒥᖕᒪᒃ, umingmak; in Woods Cree: ), is a hoofed mammal of the family Bovidae. Native to the Arctic, i ...
en unaided. This contrasts with the commonly held belief that larger packs benefit from
cooperative hunting A pack hunter or social predator is a predatory animal which hunts its prey by working together with other members of its species. Normally animals hunting in this way are closely related, and with the exceptions of chimpanzees where only male ...
to bring down large game. The size of a wolf hunting pack is related to the number of pups that survived the previous winter, adult survival, and the rate of dispersing wolves leaving the pack. The optimal pack size for hunting elk is four wolves, and for bison a large pack size is more successful. Wolves move around their territory when hunting, using the same trails for extended periods. After snowfalls, wolves find their old trails and continue using them. These follow the banks of rivers, the shorelines of lakes, ravines overgrown with shrubs, plantations, or roads and human paths. Wolves are nocturnal predators. During the winter, a pack will commence hunting in the twilight of early evening and will hunt all night, traveling tens of kilometres. Sometimes hunting large prey occurs during the day. During the summer, wolves generally tend to hunt individually, ambushing their prey and rarely giving pursuit. When hunting large gregarious prey, wolves will try to isolate an individual from its group. If successful, a wolf pack can bring down game that will feed it for days, but one error in judgement can lead to serious injury or death. Most large prey have developed defensive adaptations and behaviours. Wolves have been killed while attempting to bring down bison, elk, moose, muskoxen, and even by one of their smallest hoofed prey, the white-tailed deer. With smaller prey like
beaver Beavers are large, semiaquatic rodents in the genus ''Castor'' native to the temperate Northern Hemisphere. There are two extant species: the North American beaver (''Castor canadensis'') and the Eurasian beaver (''C. fiber''). Beavers ar ...
, geese, and hares, there is no risk to the wolf. Although people often believe wolves can easily overcome any of their prey, their success rate in hunting hoofed prey is usually low. The wolf must give chase and gain on its fleeing prey, slow it down by biting through thick hair and hide, and then disable it enough to begin feeding. After chasing and then confronting a large prey animal, the wolf makes use of its fangs and its powerful
masseter muscle In human anatomy, the masseter is one of the muscles of mastication. Found only in mammals, it is particularly powerful in herbivores to facilitate chewing of plant matter. The most obvious muscle of mastication is the masseter muscle, since it ...
s to deliver a
bite force Bite force quotient (BFQ) is a numerical value commonly used to represent the bite force of an animal, while also taking factors like the animal's size into account. The BFQ is calculated as the regression of the quotient of an animal's bite f ...
of , which is capable of breaking open the skulls of many of its prey animals. The wolf leaps at its quarry and tears at it. One wolf was observed being dragged for dozens of metres attached to the hind leg of a moose; another was seen being dragged over a fallen log while attached to a bull elk's nose. Wolves may wound large prey and then lie around resting for hours before killing it when it is weaker due to blood loss, thereby lessening the risk of injury to themselves. With medium-sized prey, such as roe deer or
sheep Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus ''Ovis'', in everyday usage it almost always refers to domesticated s ...
, wolves kill by biting the throat, severing nerve tracks and the
carotid artery Carotid artery may refer to: * Common carotid artery, often "carotids" or "carotid", an artery on each side of the neck which divides into the external carotid artery and internal carotid artery * External carotid artery, an artery on each side of t ...
, thus causing the animal to die within a few seconds to a minute. With small,
mouse A mouse ( : mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus' ...
like prey, wolves leap in a high arc and immobilize it with their forepaws. Once prey is brought down, wolves begin to feed excitedly, ripping and tugging at the carcass in all directions, and bolting down large chunks of it. The breeding pair typically monopolizes food to continue producing pups. When food is scarce, this is done at the expense of other family members, especially non-pups. The breeding pair typically eats first. They usually work the hardest at killing prey, and may rest after a long hunt and allow the rest of the family to eat undisturbed. Once the breeding pair has finished eating, the rest of the family tears off pieces of the carcass and transports them to secluded areas where they can eat in peace. Wolves typically commence feeding by gorging on the larger internal organs, like the
heart The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide t ...
,
liver The liver is a major Organ (anatomy), organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of proteins and biochemicals necessary for ...
,
lung The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of t ...
s, and
stomach The stomach is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital organ in the digestive system. The stomach i ...
lining. The
kidney The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blood ...
s and
spleen The spleen is an organ found in almost all vertebrates. Similar in structure to a large lymph node, it acts primarily as a blood filter. The word spleen comes .
are eaten once they are exposed, followed by the muscles. A wolf can eat 15–19% of its body weight in one sitting.


Infections


Viral and bacterial

Viral disease A viral disease (or viral infection) occurs when an organism's body is invaded by pathogenic viruses, and infectious virus particles (virions) attach to and enter susceptible cells. Structural Characteristics Basic structural characteristics, s ...
s carried by wolves include:
rabies Rabies is a viral disease that causes encephalitis in humans and other mammals. Early symptoms can include fever and tingling at the site of exposure. These symptoms are followed by one or more of the following symptoms: nausea, vomiting, vi ...
,
canine distemper Canine distemper virus (CDV) (sometimes termed footpad disease) is a viral disease that affects a wide variety of mammal families, including domestic and wild species of dogs, coyotes, foxes, pandas, wolves, ferrets, skunks, raccoons, and felin ...
,
canine parvovirus Canine parvovirus (also referred to as CPV, CPV2, or parvo) is a contagious virus mainly affecting dogs. CPV is highly contagious and is spread from dog to dog by direct or indirect contact with their feces. Vaccines can prevent this infection, ...
,
infectious canine hepatitis Infectious canine hepatitis (ICH) is an acute liver infection in dogs caused by ''Canine mastadenovirus A'', formerly called ''Canine adenovirus 1'' (CAV-1). CAV-1 also causes disease in wolves, coyotes, and bears, and encephalitis in foxes. The ...
,
papillomatosis Papillomatosis of skin is skin surface elevation caused by hyperplasia and enlargement of contiguous dermal papillae.Kumar, Vinay; Fausto, Nelso; Abbas, Abul (2004) ''Robbins & Cotran Pathologic Basis of Disease'' (7th ed.). Saunders. Page 1230. . ...
, and
canine coronavirus Canine coronavirus (CCoV) is an enveloped, positive-sense, single-stranded RNA virus which is a member of the species ''Alphacoronavirus 1.'' It causes a highly contagious intestinal disease worldwide in dogs. The infecting virus enters its hos ...
. Wolves are a major host for rabies in Russia, Iran,
Afghanistan Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is bordere ...
,
Iraq Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq ...
and India. In wolves, the
incubation period Incubation period (also known as the latent period or latency period) is the time elapsed between exposure to a pathogenic organism, a chemical, or radiation, and when symptoms and signs are first apparent. In a typical infectious disease, the i ...
is eight to 21 days, and results in the host becoming agitated, deserting its pack, and travelling up to a day, thus increasing the risk of infecting other wolves. Infected wolves do not show any fear of humans, most documented wolf attacks on people being attributed to rabid animals. Although canine distemper is lethal in dogs, it has not been recorded to kill wolves, except in Canada and Alaska. The canine parvovirus, which causes death by
dehydration In physiology, dehydration is a lack of total body water, with an accompanying disruption of metabolic processes. It occurs when free water loss exceeds free water intake, usually due to exercise, disease, or high environmental temperature. Mil ...
,
electrolyte imbalance Electrolyte imbalance, or water-electrolyte imbalance, is an abnormality in the concentration of electrolytes in the body. Electrolytes play a vital role in maintaining homeostasis in the body. They help to regulate heart and neurological function, ...
, and
endotoxic Lipopolysaccharides (LPS) are large molecules consisting of a lipid and a polysaccharide that are bacterial toxins. They are composed of an O-antigen, an outer core, and an inner core all joined by a covalent bond, and are found in the outer me ...
shock or
sepsis Sepsis, formerly known as septicemia (septicaemia in British English) or blood poisoning, is a life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. This initial stage is follo ...
, is largely survivable in wolves, but can be lethal to pups. Wolves may catch infectious canine hepatitis from dogs, though there are no records of wolves dying from it. Papillomatosis has been recorded only once in wolves, and likely does not cause serious illness or death, though it may alter feeding behaviours. The canine coronavirus has been recorded in Alaskan wolves, infections being most prevalent in winter months.
Bacterial diseases Pathogenic bacteria are bacteria that can cause disease. This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and are often Probiotic, beneficial but others can cause infectious diseases. The n ...
carried by wolves include:
brucellosis Brucellosis is a highly contagious zoonosis caused by ingestion of unpasteurized milk or undercooked meat from infected animals, or close contact with their secretions. It is also known as undulant fever, Malta fever, and Mediterranean fever. The ...
,
Lyme disease Lyme disease, also known as Lyme borreliosis, is a vector-borne disease caused by the ''Borrelia'' bacterium, which is spread by ticks in the genus ''Ixodes''. The most common sign of infection is an expanding red rash, known as erythema migran ...
,
leptospirosis Leptospirosis is a blood infection caused by the bacteria ''Leptospira''. Signs and symptoms can range from none to mild (headaches, muscle pains, and fevers) to severe ( bleeding in the lungs or meningitis). Weil's disease, the acute, severe ...
,
tularemia Tularemia, also known as rabbit fever, is an infectious disease caused by the bacterium ''Francisella tularensis''. Symptoms may include fever, skin ulcers, and enlarged lymph nodes. Occasionally, a form that results in pneumonia or a throat infe ...
,
bovine tuberculosis Bovines ( subfamily Bovinae) comprise a diverse group of 10 genera of medium to large-sized ungulates, including cattle, bison, African buffalo, water buffalos, and the four-horned and spiral-horned antelopes. The evolutionary relationship betw ...
,
listeriosis Listeriosis is a bacterial infection most commonly caused by ''Listeria monocytogenes'', although '' L. ivanovii'' and '' L. grayi'' have been reported in certain cases. Listeriosis can cause severe illness, including severe sepsis, men ...
and
anthrax Anthrax is an infection caused by the bacterium ''Bacillus anthracis''. It can occur in four forms: skin, lungs, intestinal, and injection. Symptom onset occurs between one day and more than two months after the infection is contracted. The sk ...
. Wolves can catch ''
Brucella suis ''Brucella suis'' is a bacterium that causes swine brucellosis, a zoonosis that affects pigs. The disease typically causes chronic inflammatory lesions in the reproductive organs of susceptible animals or orchitis, and may even affect joints and ...
'' from wild and domestic reindeer. While adult wolves tend not to show any clinical signs, it can severely weaken the pups of infected females. Although lyme disease can debilitate individual wolves, it does not appear to significantly affect wolf populations. Leptospirosis can be contracted through contact with infected prey or urine, and can cause
fever Fever, also referred to as pyrexia, is defined as having a body temperature, temperature above the human body temperature, normal range due to an increase in the body's temperature Human body temperature#Fever, set point. There is not a single ...
,
anorexia Anorexia nervosa, often referred to simply as anorexia, is an eating disorder characterized by low weight, food restriction, body image disturbance, fear of gaining weight, and an overpowering desire to be thin. ''Anorexia'' is a term of Gre ...
, vomiting,
anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, th ...
,
hematuria Hematuria or haematuria is defined as the presence of blood or red blood cells in the urine. “Gross hematuria” occurs when urine appears red, brown, or tea-colored due to the presence of blood. Hematuria may also be subtle and only detectable w ...
, icterus, and death. Wolves living near farms are more vulnerable to the disease than those living in the wilderness, probably because of prolonged contact with infected domestic animal waste. Wolves may catch tularemia from
lagomorph The lagomorphs are the members of the taxonomic order Lagomorpha, of which there are two living families: the Leporidae (hares and rabbits) and the Ochotonidae (pikas). The name of the order is derived from the Ancient Greek ''lagos'' (λαγ ...
prey, though its effect on wolves is unknown. Although bovine tuberculosis is not considered a major threat to wolves, it has been recorded to have killed two wolf pups in Canada.


Parasitic

Wolves carry
ectoparasite Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...
s and
endoparasite Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...
s; those in the former
Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national ...
have been recorded to carry at least 50 species. Most of these parasites infect wolves without adverse effects, though the effects may become more serious in sick or malnourished specimens.
Parasitic infection A parasitic disease, also known as parasitosis, is an infectious disease caused by parasites. Parasites are organisms which derive sustenance from its host while causing it harm. The study of parasites and parasitic diseases is known as parasitolog ...
in wolves is of particular concern to people. Wolves can spread them to dogs, which in turn can carry the parasites to humans. In areas where wolves inhabit pastoral areas, the parasites can be spread to livestock. Wolves are often infested with a variety of
arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...
exoparasites, including
flea Flea, the common name for the order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. Fleas live by ingesting the blood of their hosts. Adult fleas grow to about long, a ...
s,
tick Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes. Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". Ticks are external parasites, living by ...
s, Louse, lice, and mites. The most harmful to wolves, particularly pups, is the mange mite (''Sarcoptes scabiei''), though they rarely develop full-blown mange, unlike foxes. Lice, such as ''Trichodectes canis'', may cause sickness in wolves, but rarely death. Ticks of the genus ''Ixodes'' can infect wolves with Lyme disease and Rocky Mountain spotted fever. The tick ''Dermacentor pictus'' also infests wolves. Other ectoparasites include Mallophaga, chewing lice, Sucking louse, sucking lice and the fleas ''Pulex irritans'' and ''Ctenocephalides canis''. Endoparasites known to infect wolves include: protozoans and helminths (Trematoda, flukes, tapeworms, roundworms and thorny-headed worms). Of 30,000 protozoan species, only a few have been recorded to infect wolves: ''Isospora'', ''Toxoplasma'', ''Sarcocystis'', ''Babesia'', and ''Giardia''. Some wolves carry ''Neospora caninum'', which can be spread to cattle and is correlated with bovine miscarriages. Among flukes, the most common in North American wolves is ''Alaria (trematode), Alaria'', which infects small rodents and amphibians which are eaten by wolves. Upon reaching maturity, ''Alaria'' migrates to the wolf's intestine, but does little harm. ''Metorchis conjunctus'', which enters wolves through eating fish, infects the wolf's liver or gall bladder, causing liver disease, inflammation of the pancreas, and emaciation. Most other fluke species reside in the wolf's intestine, though ''Paragonimus westermani'' lives in the lungs. Tapeworms are commonly found in wolves, as their primary hosts are ungulates, small mammals, and fish, which wolves feed upon. Tapeworms generally cause little harm in wolves, though this depends on the number and size of the parasites, and the sensitivity of the host. Symptoms often include constipation, toxic and allergic reactions, irritation of the intestinal mucosa, and malnutrition. Infections by the tapeworm ''Echinococcus granulosus'' in ungulate populations tend to increase in areas with high wolf densities, as wolves can shed ''Echinoccocus'' eggs in their feces onto grazing areas. Wolves can carry over 30 roundworm species, though most roundworm infections appear benign, depending on the number of worms and the age of the host. ''Ancylostoma caninum'' attaches itself on the intestinal wall to feed on the host's blood, and can cause hyperchromic anemia, emaciation, diarrhea, and possibly death. ''Toxocara canis'', a hookworm known to infect wolf pups in the uterus, can cause intestinal irritation, bloating, vomiting, and diarrhea. Wolves may catch ''Dioctophyma renale'' from American mink, minks, which infects the kidneys, and can grow to lengths of . ''D. renale'' causes the complete destruction of the kidney's functional tissue and can be fatal if both kidneys are infected. Wolves can tolerate low levels of ''Dirofilaria immitis'' for many years without showing any ill effects, though high levels can kill wolves through cardiac enlargement and congestive hepatopathy. Wolves probably become infected with ''Trichinella spiralis'' by eating infected ungulates. Although ''T. spiralis'' is not known to produce clinical signs in wolves, it can cause emaciation, salivation, and crippling muscle pains in dogs. Thorny-headed worms rarely infect wolves, though three species have been identified in Russian wolves: ''Nicolla skrjabini'', ''Macracanthorhynchus catulinus'', and ''Moniliformis moniliformis''.


Status and conservation

The global wild wolf population in 2003 was estimated at 300,000. Wolf population declines have been arrested since the 1970s. This has fostered recolonization and reintroduction in parts of its former range as a result of legal protection, changes in land use, and rural human population shifts to cities. Competition with humans for livestock and game species, concerns over the danger posed by wolves to people, and habitat fragmentation pose a continued threat to the wolf. Despite these threats, the International Union for Conservation of Nature, IUCN classifies the wolf as Least Concern on its IUCN Red List, Red List due to its relatively widespread range and stable population. The species is listed under CITES#Appendix II, AppendixII of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), meaning international trade in the species (including parts and derivatives) is regulated. However, populations of Bhutan, India, Nepal and Pakistan are listed in CITES#Appendix I, AppendixI which prohibits commercial international trade in wild-sourced specimens.


North America

In Canada, 50,000–60,000 wolves live in 80% of their historical range, making Canada an important stronghold for the species. Under Canadian law, First Nations in Canada, First Nations people can hunt wolves without restrictions, but others must acquire licenses for the hunting and trapping seasons. As many as 4,000 wolves may be harvested in Canada each year. The wolf is a protected species in national parks under the Canada National Parks Act. In Alaska, 7,000–11,000 wolves are found on 85% of the state's area. Wolves may be hunted or trapped with a license; around 1,200 wolves are harvested annually. In the contiguous United States, wolf declines were caused by the expansion of agriculture, the decimation of the wolf's main prey species like the American bison, and extermination campaigns. Wolves were given protection under the Endangered Species Act (ESA) of 1973, and have since returned to parts of their former range thanks to both natural recolonizations and History of wolves in Yellowstone#Re-introduction (1995–present), reintroductions in Yellowstone and Idaho. The repopulation of wolves in Midwestern United States has been concentrated in the Western Great Lakes forests, Great Lakes states of Minnesota, Wisconsin and Michigan where wolves number over 4,000 as of 2018. Wolves also occupy much of the northern Rocky Mountains region, with at least 1,704 wolves in Montana, Idaho and Wyoming as of 2015. They have also established populations in Washington and Oregon. In Mexico and parts of the southwestern United States, the Mexican and U.S. governments collaborated from 1977 to 1980 in capturing all Mexican wolves remaining in the wild to prevent their extinction and established captive breeding programs for reintroduction.


Eurasia

Europe, excluding Russia, Belarus and Ukraine, has 17,000 wolves in more than 28 countries. In many countries of the European Union, the wolf is strictly protected under the 1979 Berne Convention on the Conservation of European Wildlife and Natural Habitats (AppendixII) and the 1992 Habitats Directive, Council Directive 92/43/EEC on the Conservation of Natural Habitats and of Wild Fauna and Flora (AnnexII andIV). There is extensive legal protection in many European countries, although there are national exceptions. Wolves have been persecuted in Europe for centuries, having been exterminated in Wolves in Great Britain, Great Britain by 1684, in Wolves in Ireland, Ireland by 1770, in Central Europe by 1899, in France by the 1930s, and in much of Scandinavia by the early 1970s. They continued to survive in parts of Finland, Eastern Europe and Southern Europe. Since 1980, European wolves have rebounded and expanded into parts of their former range. The decline of the traditional pastoral and rural economies seems to have ended the need to exterminate the wolf in parts of Europe. As of 2016, estimates of wolf numbers include: 4,000 in the Balkans, 3,460–3,849 in the Carpathian Mountains, 1,700–2,240 in the Baltic states, 1,100–2,400 in the Italian peninsula, and around 2,500 in the northwest Iberian peninsula as of 2007. In the former Soviet Union, wolf populations have retained much of their historical range despite Soviet-era large scale extermination campaigns. Their numbers range from 1,500 in Georgia, to 20,000 in Kazakhstan and up to 45,000 in Russia. In Russia, the wolf is regarded as a pest because of its attacks on livestock, and wolf management means controlling their numbers by destroying them throughout the year. Russian history over the past century shows that reduced hunting leads to an abundance of wolves. The Russian government has continued to pay bounties for wolves and annual harvests of 20–30% do not appear to significantly affect their numbers. In the Middle East, only Israel and Oman give wolves explicit legal protection. Israel has protected its wolves since 1954 and has maintained a moderately sized population of 150 through effective enforcement of conservation policies. These wolves have moved into neighboring countries. Approximately 300–600 wolves inhabit the Arabian Peninsula. The wolf also appears to be widespread in Iran. Turkey has an estimated population of about 7,000 wolves. Outside of Turkey, wolf populations in the Middle East may total 1,000–2,000. In southern Asia, the northern regions of Afghanistan and Pakistan are important strongholds for wolves. The wolf has been protected in India since 1972. The Indian wolf is distributed across the states of Gujarat, Rajasthan, Haryana, Uttar Pradesh, Madhya Pradesh, Maharashtra, Karnataka and Andhra Pradesh. As of 2019, it is estimated that there are around 2,000–3,000 Indian wolves in the country. In East Asia, Mongolia's population numbers 10,000–20,000. In China, Heilongjiang has roughly 650 wolves, Xinjiang has 10,000 and Tibet Autonomous Region, Tibet has 2,000. 2017 evidence suggests that wolves range across all of mainland China. Wolves have been historically persecuted in China but have been legally protected since 1998. The last Japanese wolf was captured and killed in 1905.


Relationships with humans


In culture


In folklore, religion and mythology

The wolf is a common motif in the mythologies and cosmologies of peoples throughout its historical range. The Ancient Greeks associated wolves with Apollo, the god of light and order. The Ancient Romans connected the wolf with their god of war and agriculture Mars (mythology), Mars, and believed their city's founders, Romulus and Remus, were suckled by a She-wolf (Roman mythology), she-wolf. Norse mythology includes the feared giant wolf Fenrir, and Geri and Freki, Odin's faithful pets. In Chinese astronomy, the wolf represents Sirius and guards the heavenly gate. In China, the wolf was traditionally associated with greed and cruelty and wolf epithets were used to describe negative behaviours such as cruelty ("wolf's heart"), mistrust ("wolf's look") and lechery ("wolf-sex"). In both Hinduism and Buddhism, the wolf is ridden by gods of protection. In Vedic Hinduism, the wolf is a symbol of the night and the daytime quail must escape from its jaws. In Tantric Buddhism, wolves are depicted as inhabitants of graveyards and destroyers of corpses. In the Pawnee people, Pawnee creation myth, the wolf was the first animal brought to Earth. When humans killed it, they were punished with death, destruction and the loss of immortality. For the Pawnee, Sirius is the "wolf star" and its disappearance and reappearance signified the wolf moving to and from the spirit world. Both Pawnee and Blackfoot call the Milky Way the "wolf trail". The wolf is also an important Crest (heraldry), crest symbol for clans of the Pacific Northwest like the Kwakwakaʼwakw. The concept of people turning into wolves, and the inverse, has been present in many cultures. One Greek myth tells of Lycaon (king of Arcadia), Lycaon being transformed into a wolf by Zeus as punishment for his evil deeds. The legend of the werewolf has been widespread in European folklore and involves people willingly turning into wolves to attack and kill others. The Navajo have traditionally believed that skin-walker, witches would turn into wolves by donning wolf skins and would kill people and raid graveyards. The Dena'ina believed wolves were once men and viewed them as brothers.


In fable and literature

Aesop featured wolves in several of his Aesop's Fables, fables, playing on the concerns of Ancient Greece's settled, sheep-herding world. His most famous is the fable of "The Boy Who Cried Wolf", which is directed at those who knowingly raise false alarms, and from which the idiomatic phrase "to wikt:cry wolf, cry wolf" is derived. Some of his other fables concentrate on maintaining the trust between shepherds and guard dogs in their vigilance against wolves, as well as anxieties over the close relationship between wolves and dogs. Although Aesop used wolves to warn, criticize and moralize about human behaviour, his portrayals added to the wolf's image as a deceitful and dangerous animal. The Bible uses an image of a wolf lying with a lamb in a utopian vision of the future. In the New Testament, Jesus is said to have used wolves as illustrations of the dangers his followers, whom he represents as sheep, would face should they follow him. Isengrim the wolf, a character first appearing in the 12th-century Latin poem ''Ysengrimus'', is a major character in the Reynard Cycle, where he stands for the low nobility, whilst his adversary, Reynard the fox, represents the peasant hero. Isengrim is forever the victim of Reynard's wit and cruelty, often dying at the end of each story. The tale of "Little Red Riding Hood", first written in 1697 by Charles Perrault, is considered to have further contributed to the wolf's negative reputation in the Western world. The Big Bad Wolf is portrayed as a villain capable of imitating human speech and disguising itself with human clothing. The character has been interpreted as an allegorical sexual predator. Villainous wolf characters also appear in ''The Three Little Pigs'' and "The Wolf and the Seven Young Goats". The hunting of wolves, and their attacks on humans and livestock, feature prominently in Russian literature, and are included in the works of Leo Tolstoy, Anton Chekhov, Nikolay Nekrasov, Ivan Bunin, Leonid Pavlovich Sabaneyev, and others. Tolstoy's ''War and Peace'' and Chekhov's ''Peasants'' both feature scenes in which wolves are hunted with hounds and Borzois. The musical ''Peter and the Wolf'' involves a wolf being captured for eating a duck, but is spared and sent to a zoo. Wolves are among the central characters of Rudyard Kipling's ''The Jungle Book''. His portrayal of wolves has been praised posthumously by wolf biologists for his depiction of them: rather than being villainous or gluttonous, as was common in wolf portrayals at the time of the book's publication, they are shown as living in amiable family groups and drawing on the experience of infirm but experienced elder pack members. Farley Mowat's largely fictional 1963 memoir ''Never Cry Wolf'' is widely considered to be the most popular book on wolves, having been adapted into a Never Cry Wolf (film), Hollywood film and taught in several schools decades after its publication. Although credited with having changed popular perceptions on wolves by portraying them as loving, cooperative and noble, it has been criticized for its idealization of wolves and its factual inaccuracies.


Conflicts

Human presence appears to stress wolves, as seen by increased cortisol levels in instances such as snowmobiling near their territory.


Predation on livestock

Livestock depredation has been one of the primary reasons for hunting wolves and can pose a severe problem for wolf conservation. As well as causing economic losses, the threat of wolf predation causes great stress on livestock producers, and no foolproof solution of preventing such attacks short of exterminating wolves has been found. Some nations help offset economic losses to wolves through compensation programs or state insurance. Domesticated animals are easy prey for wolves, as they have been bred under constant human protection, and are thus unable to defend themselves very well. Wolves typically resort to attacking livestock when wild prey is depleted. In Eurasia, a large part of the diet of some wolf populations consists of livestock, while such incidents are rare in North America, where healthy populations of wild prey have been largely restored. The majority of losses occur during the summer grazing period, untended livestock in remote pastures being the most vulnerable to wolf predation. The most frequently targeted livestock species are sheep (Europe), Reindeer herding, domestic reindeer (northern Scandinavia), goats (India), horses (Mongolia), cattle and Domestic turkey, turkeys (North America). The number of animals killed in single attacks varies according to species: most attacks on cattle and horses result in one death, while turkeys, sheep and domestic reindeer may be killed in surplus. Wolves mainly attack livestock when the animals are grazing, though they occasionally break into fenced enclosures.


Competition with dogs

A review of the studies on the competitive effects of dogs on Sympatry, sympatric carnivores did not mention any research on competition between dogs and wolves. Competition would favour the wolf, which is known to kill dogs; however, wolves usually live in pairs or in small packs in areas with high human persecution, giving them a disadvantage when facing large groups of dogs. Wolves kill dogs on occasion, and some wolf populations rely on dogs as an important food source. In Croatia, wolves kill more dogs than sheep, and wolves in Russia appear to limit stray dog populations. Wolves may display unusually bold behaviour when attacking dogs accompanied by people, sometimes ignoring nearby humans. Wolf attacks on dogs may occur both in house yards and in forests. Wolf attacks on hunting dogs are considered a major problem in Scandinavia and Wisconsin. The most frequently killed hunting breeds in Scandinavia are Harrier (dog), Harriers, older animals being most at risk, likely because they are less timid than younger animals, and react to the presence of wolves differently. Large hunting dogs such as Jämthund, Swedish Elkhounds are more likely to survive wolf attacks because of their better ability to defend themselves. Although the number of dogs killed each year by wolves is relatively low, it induces a fear of wolves entering villages and farmyards to prey on them. In many cultures, dogs are seen as family members, or at least working team members, and losing one can lead to strong emotional responses such as demanding more liberal hunting regulations. Dogs that are employed to guard sheep help to mitigate human–wolf conflicts, and are often proposed as one of the non-lethal tools in the conservation of wolves. Shepherd dogs are not particularly aggressive, but they can disrupt potential wolf predation by displaying what is to the wolf ambiguous behaviours, such as barking, social greeting, invitation to play or aggression. The historical use of shepherd dogs across Eurasia has been effective against wolf predation, especially when confining sheep in the presence of several livestock guardian dogs. Shepherd dogs are sometimes killed by wolves.


Attacks on humans

The fear of wolves has been pervasive in many societies, though humans are not part of the wolf's natural prey. How wolves react to humans depends largely on their prior experience with people: wolves lacking any negative experience of humans, or which are food-conditioned, may show little fear of people. Although wolves may react aggressively when provoked, such attacks are mostly limited to quick bites on extremities, and the attacks are not pressed. Predatory attacks may be preceded by a long period of habituation, in which wolves gradually lose their fear of humans. The victims are repeatedly bitten on the head and face, and are then dragged off and consumed unless the wolves are driven off. Such attacks typically occur only locally and do not stop until the wolves involved are eliminated. Predatory attacks can occur at any time of the year, with a peak in the June–August period, when the chances of people entering forested areas (for livestock grazing or berry and mushroom picking) increase. Cases of non-rabid wolf attacks in winter have been recorded in Belarus, Kirov Oblast, Kirov and Irkutsk Oblast, Irkutsk oblasts, Karelia and Ukraine. Also, wolves with pups experience greater food stresses during this period. The majority of victims of predatory wolf attacks are children under the age of 18 and, in the rare cases where adults are killed, the victims are almost always women. Indian wolves have a history of preying on children, a phenomenon called "child-lifting". They may be taken primarily in the spring and summer periods during the evening hours, and often within human settlements. Cases of rabid wolves are low when compared to other species, as wolves do not serve as primary reservoirs of the disease, but can be infected by animals such as dogs, jackals and foxes. Incidents of rabies in wolves are very rare in North America, though numerous in the eastern Mediterranean, the Middle East and Central Asia. Wolves apparently develop the "furious" phase of rabies to a very high degree. This, coupled with their size and strength, makes rabid wolves perhaps the most dangerous of rabid animals. Bites from rabid wolves are 15 times more dangerous than those of rabid dogs. Rabid wolves usually act alone, travelling large distances and often biting large numbers of people and domestic animals. Most rabid wolf attacks occur in the spring and autumn periods. Unlike with predatory attacks, the victims of rabid wolves are not eaten, and the attacks generally occur only on a single day. The victims are chosen at random, though most cases involve adult men. During the fifty years up to 2002, there were eight fatal attacks in Europe and Russia, and more than two hundred in southern Asia.


Human hunting of wolves

Theodore Roosevelt said wolves are difficult to hunt because of their elusiveness, sharp senses, high endurance, and ability to quickly incapacitate and kill a dog. Historic methods included killing of spring-born litters in their dens, coursing with dogs (usually combinations of sighthounds, Bloodhounds and Fox Terriers), poisoning with strychnine, and trapping. A popular method of wolf hunting in Russia involves trapping a pack within a small area by encircling it with fladry poles carrying a human scent. This method relies heavily on the wolf's fear of human scents, though it can lose its effectiveness when wolves become accustomed to the odor. Some hunters can lure wolves by imitating their calls. In Kazakhstan and Mongolia, wolves are traditionally hunted with eagles and falcons, though this practice is declining, as experienced falconers are becoming few in number. Shooting wolves from aircraft is highly effective, due to increased visibility and direct lines of fire. Several types of dog, including the Borzoi and Taigan, Kyrgyz Tajgan, have been specifically bred for wolf hunting.


As pets and working animals

Wolves and wolf-dog hybrids are sometimes kept as exotic pets. Although closely related to domestic dogs, wolves do not show the same tractability as dogs in living alongside humans, being generally less responsive to human commands and more likely to act aggressively. A person is more likely to be fatally mauled by a pet wolf or wolf-dog hybrid than by a dog.


Notes


References


Bibliography

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External links


The International Wolf CenterStaying Safe in Wolf Country
Alaska Department of Fish and Game, ADFG (January 2009) *Watc
''Death of a Legend''
an
''Cry of the Wild''
by Bill Mason {{featured article Apex predators Articles containing video clips Mammals of Asia Mammals of Europe Mammals of North America Extant Middle Pleistocene first appearances Holarctic fauna Mammals described in 1758 Paraphyletic groups Pleistocene carnivorans Scavengers Taxa named by Carl Linnaeus Wolves