''Canis'' is a
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 ...
of the
Caninae
The Caninae, known as canines, are one of three subfamily, subfamilies found within the Canidae, canid family. The other two canid subfamilies are the extinct Borophaginae and Hesperocyoninae. The Caninae includes all living canids and their most ...
which includes multiple
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, ...
species, such as
wolves
The wolf (''Canis lupus''; plural, : wolves), also known as the gray wolf or grey wolf, is a large Canis, canine native to Eurasia and North America. More than thirty subspecies of Canis lupus, subspecies of ''Canis lupus'' have been reco ...
,
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 ...
s,
coyotes
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
golden jackals
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 ...
. Species of this genus are distinguished by their moderate to large size, their massive, well-developed skulls and dentition, long legs, and comparatively short ears and tails.
[Heptner, V. G.; Naumov, N. P. (1998). ''Mammals of the Soviet Union'' Vol.II Part 1a, SIRENIA AND CARNIVORA (Sea Cows, Wolves and Bears). Science Publishers, Inc. USA. pp. 124–129. .]
Taxonomy
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'' (
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 ...
, 1758) was published in the
10th edition of Systema Naturae
The 10th edition of ''Systema Naturae'' is a book written by Swedish naturalist Carl Linnaeus and published in two volumes in 1758 and 1759, which marks the starting point of zoological nomenclature. In it, Linnaeus introduced binomial nomencla ...
[ and included the dog-like carnivores: the domestic dog, wolves, coyotes and jackals. All species within ''Canis'' are ]phylogenetically
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 ...
closely related with 78 chromosome
A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...
s and can potentially interbreed
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in ...
.[ In 1926, the ]International Commission on Zoological Nomenclature
The International Commission on Zoological Nomenclature (ICZN) is an organization dedicated to "achieving stability and sense in the scientific naming of animals". Founded in 1895, it currently comprises 26 commissioners from 20 countries.
Orga ...
(ICZN) in Opinion 91 included Genus ''Canis'' on its ''Official Lists and Indexes of Names in Zoology''.[ In 1955, the ICZN's Direction 22 added '']Canis familiaris
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 ...
'' as 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 ...
for genus ''Canis'' to the official list.[
The cladogram below is based on the DNA phylogeny of Lindblad-Toh ''et al''. (2005),][ modified to incorporate recent findings on ''Canis'' species,][
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 ...
/SSC Canid Specialist Group recommends that because DNA evidence shows the side-striped jackal
The side-striped jackal (''Lupulella adusta)'' is a canine native to central and southern Africa.
Unlike the smaller and related black-backed jackal (''Lupulella mesomelas''), which dwells in open plains, the side-striped jackal primarily dwell ...
(''Canis adustus'') and black-backed jackal
The black-backed jackal (''Lupulella mesomelas),'' also called the silver-backed jackal, is a medium-sized canine native to eastern and southern Africa. These regions are separated by roughly 900 kilometers.
One region includes the southe ...
(''Canis mesomelas'') to form a monophyletic lineage that sits outside of the ''Canis''/''Cuon''/''Lycaon'' clade, that they should be placed in a distinct genus, ''Lupulella'' Hilzheimer, 1906 with the names ''Lupulella adusta'' and ''Lupulella mesomelas''.[
]
Evolution
:''See further: Evolution of the canids
The fossil record shows that feliform
Feliformia is a suborder within the order Carnivora consisting of "cat-like" carnivorans, including cats (large and small), hyenas, mongooses, viverrids, and related taxa. Feliformia stands in contrast to the other suborder of Carnivora, Cani ...
s and caniform
Caniformia is a suborder within the order Carnivora consisting of "dog-like" carnivorans. They include dogs (wolves, foxes, etc.), bears, raccoons, and mustelids. The Pinnipedia (seals, walruses and sea lions) are also assigned to this group. ...
s emerged within the clade Carnivoramorpha 43 million YBP
Before Present (BP) years, or "years before present", is a time scale used mainly in archaeology, geology and other scientific disciplines to specify when events occurred relative to the origin of practical radiocarbon dating in the 1950s. Becau ...
.[ The caniforms included the fox-like genus '']Leptocyon
The genus ''Leptocyon'' (Greek: ''leptos'' slender + ''cyon'' dog) includes 11 species and was the first canine. They were small and weighed around . They first appeared in North America around 34 million years ago in the Oligocene at the same ...
'', whose various species existed from 24 million YBP before branching 11.9 million YBP into ''Vulpes
'' Vulpes '' is a genus of the sub-family Caninae. The members of this genus are colloquially referred to as true foxes, meaning they form a proper clade. The word " fox" occurs in the common names of all species of the genus, but also appea ...
'' (foxes) and Canini (canines). The jackal-sized ''Eucyon
''Eucyon'' (Greek: : good, true; : dog) is an extinct genus of medium omnivorous coyote-like canid that first appeared in the Western United States during the late Middle Miocene 10 million years ago. It was the size of a jackal and weighed ...
'' existed in North America from 10 million YBP and by the Early Pliocene
Early may refer to:
History
* The beginning or oldest part of a defined historical period, as opposed to middle or late periods, e.g.:
** Early Christianity
** Early modern Europe
Places in the United States
* Early, Iowa
* Early, Texas
* Early ...
about 6-5 million YBP the coyote-like ''Eucyon davisi''[ invaded Eurasia. The canids that had emigrated from North America to Eurasia – '']Eucyon
''Eucyon'' (Greek: : good, true; : dog) is an extinct genus of medium omnivorous coyote-like canid that first appeared in the Western United States during the late Middle Miocene 10 million years ago. It was the size of a jackal and weighed ...
'', ''Vulpes
'' Vulpes '' is a genus of the sub-family Caninae. The members of this genus are colloquially referred to as true foxes, meaning they form a proper clade. The word " fox" occurs in the common names of all species of the genus, but also appea ...
'', and ''Nyctereutes
''Nyctereutes'' (Greek: ''nyx, nykt-'' "night" + ''ereutēs'' "wanderer") is a genus of canid which includes only two extant species both known as raccoon dogs; the common raccoon dog (''Nyctereutes procyonoides'') and the Japanese raccoon dog (' ...
'' – were small to medium-sized predators during the Late Miocene and Early Pliocene but they were not the top predators.
Around 5 million years ago, some of the Old World ''Eucyon'' evolved into the first members of ''Canis'', and the position of the canids would change to become a dominant predator across the Palearctic
The Palearctic or Palaearctic is the largest of the eight biogeographic realms of the Earth. It stretches across all of Eurasia north of the foothills of the Himalayas, and North Africa.
The realm consists of several bioregions: the Euro-Sibe ...
. The wolf-sized '' C. chihliensis'' appeared in northern China in the Mid-Pliocene around 4-3 million YBP. This was followed by an explosion of ''Canis'' evolution across Eurasia in the Early Pleistocene around 1.8 million YBP in what is commonly referred to as the ''wolf event''. It is associated with the formation of the mammoth steppe
During the Last Glacial Maximum, the mammoth steppe, also known as steppe-tundra, was the Earth's most extensive biome. It spanned from Spain eastward across Eurasia to Canada and from the List of islands in the Arctic Ocean, arctic islands sout ...
and continental glaciation. ''Canis'' spread to Europe in the forms of '' C. arnensis'', '' C. etruscus'', and '' C. falconeri''.[
For ''Canis'' populations in the New World, ''Eucyon'' in North America gave rise to early North American ''Canis'' which first appeared in the ]Miocene
The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
(6 million YBP) in south-western USA and Mexico. By 5 million YBP the larger ''Canis lepophagus
''Canis lepophagus'' (Latin: : 'dog'; : 'hare' or 'rabbit'; suffix : '-eating'; hence hare-eating dog) is an extinct species of canid which was endemic to much of North America during the Early Pliocene. It is notable because its lineage is prop ...
'', ancestor of wolves and coyotes, appeared in the same region.
However, a 2021 genetic study of the 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 Late ...
(''Aenocyon dirus''), previously considered a member of ''Canis'', found that it represented the last member of an ancient lineage of canines originally indigenous to the New World that had diverged prior to the appearance of ''Canis'', and that its lineage had been distinct since the Miocene with no evidence of introgression with ''Canis''. The study hypothesized that the Neogene
The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...
canids in the New World, '' Canis armbrusteri'' and ''Canis edwardii
''Canis edwardii'', also known as Edward's wolf, is an extinct species of wolf in the genus ''Canis'' which was endemic to North America three million years ago from the Late Blancan stage of the Pliocene epoch and was extinct by the end of the I ...
'', were possibly members of the distinct dire wolf lineage that had convergently evolved
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last com ...
a very similar appearance to members of ''Canis''. True members of ''Canis'', namely the gray wolf
The wolf (''Canis lupus''; : wolves), also known as the gray wolf or grey wolf, is a large canine native to Eurasia and North America. More than thirty subspecies of ''Canis lupus'' have been recognized, and gray wolves, as popularly ...
and 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 ...
, likely only arrived in the New World during 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 ...
, where their dietary flexibility and/or ability to hybridize with other canids allowed them to survive the Quaternary extinction event
The Quaternary period (from 2.588 ± 0.005 million years ago to the present) has seen the extinctions of numerous predominantly megafaunal species, which have resulted in a collapse in faunal density and diversity and the extinction of key ecolog ...
, unlike the dire wolf.
''Xenocyon
''Xenocyon'' ("strange dog") is an extinct subgenus of ''Canis''. The group includes ''Canis'' (''Xenocyon'') ''africanus'', ''Canis'' (''Xenocyon'') ''antonii'' and ''Canis'' (''Xenocyon'') ''falconeri'' that gave rise to ''Canis'' (''Xenocyon'' ...
'' (strange wolf) is an extinct subgenus
In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus.
In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...
of ''Canis''.[ The diversity of the ''Canis'' group decreased by the end of the ]Early Pleistocene
The Early Pleistocene is an unofficial sub-epoch in the international geologic timescale in chronostratigraphy, being the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently estimated to span the time ...
to the Middle Pleistocene
The Chibanian, widely known by its previous designation of Middle Pleistocene, is an age in the international geologic timescale or a stage in chronostratigraphy, being a division of the Pleistocene Epoch within the ongoing Quaternary Period. The ...
and was limited in Eurasia to the small wolves of the ''Canis mosbachensis
''Canis mosbachensis'', sometimes known as the Mosbach wolf, is an extinct small wolf that once inhabited Eurasia from the Middle Pleistocene era to the Late Pleistocene. It is widely accepted as the ancestor of '' Canis lupus'', the grey wolf.
...
–Canis variabilis'' group and the large hypercarnivorous ''Canis (Xenocyon) lycaonoides''.[ The hypercarnivore ''Xenocyon'' gave rise to the modern ]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 the African wild 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 '' Ly ...
.[
]
Dentition and biteforce
Dentition
Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiolo ...
relates to the arrangement of teeth in the mouth, with the dental notation
Dental professionals, in writing or speech, use several different dental notation systems for associating information with a specific tooth. The three most common systems are the FDI World Dental Federation notation (ISO 3950), the Universal Nu ...
for the upper-jaw teeth using the upper-case letters I to denote incisors
Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, wh ...
, C for canines
Canine may refer to:
Zoology and anatomy
* a dog-like Canid animal in the subfamily Caninae
** ''Canis'', a genus including dogs, wolves, coyotes, and jackals
** Dog, the domestic dog
* Canine tooth, in mammalian oral anatomy
People with the surn ...
, P for premolars
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 ...
, and M for 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 ...
, and the lower-case letters i, c, p and m to denote the mandible teeth. Teeth are numbered using one side of the mouth and from the front of the mouth to the back. In carnivores
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 ...
, the upper premolar P4 and the lower molar m1 form the carnassials
Carnassials are paired upper and lower teeth modified in such a way as to allow enlarged and often self-sharpening edges to pass by each other in a shearing manner. This adaptation is found in carnivorans, where the carnassials are the modified f ...
that are used together in a scissor-like action to shear the muscle and tendon of prey.[
]Canids
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 ...
use their premolars for cutting and crushing except for the upper fourth premolar P4 (the upper carnassial) that is only used for cutting. They use their molars for grinding except for the lower first molar m1 (the lower carnassial) that has evolved for both cutting and grinding depending on the candid's dietary adaptation. On the lower carnassial the trigonid
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 ...
is used for slicing and the talonid
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 ...
is used for grinding. The ratio between the trigonid and the talonid indicates a carnivore's dietary habits, with a larger trigonid indicating a hypercarnivore
A hypercarnivore is an animal which has a diet that is more than 70% meat, either via active predation or by scavenging. The remaining non-meat diet may consist of non-animal foods such as fungi, fruits or other plant material. Some extant examp ...
and a larger talonid indicating a more omnivorous
An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nutri ...
diet.[ Because of its low variability, the length of the lower carnassial is used to provide an estimate of a carnivore's body size.][
A study of the estimated bite force at the canine teeth of a large sample of living and fossil mammalian predators, when adjusted for their body mass, found that for ]placental
Placental mammals (infraclass Placentalia ) are one of the three extant subdivisions of the class Mammalia, the other two being Monotremata and Marsupial
Marsupials are any members of the mammalian infraclass Marsupialia. All extant marsup ...
mammals the bite force at the canines (in Newtons/kilogram of body weight) was greatest 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 Late ...
(163), followed among the modern canids
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 ...
by the four hypercarnivores that often prey on animals larger than themselves: the African hunting dog (142), the gray wolf (136), the dhole (112), and the dingo (108). The bite force at the carnassials showed a similar trend to the canines. A predator's largest prey size is strongly influenced by its biomechanical limits.[
]
Behavior
Description and sexual dimorphism
There is little variance among male and female canids. Canids tend to live as monogamous pairs. Wolves, dholes
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. ...
, 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 ...
s, and jackals
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 ...
live in groups that include breeding pairs and their offspring. Wolves may live in extended family groups. To take prey larger than themselves, the African wild dog, the dhole, and the gray wolf depend on their jaws as they cannot use their forelimbs to grapple with prey. They work together as a pack consisting of an alpha pair and their offspring from the current and previous years.[ Social mammal predators prey on herbivores with a body mass similar to that of the combined mass of the predator pack.][ The gray wolf specializes in preying on the vulnerable individuals of large prey,][ and a pack of timber wolves can bring down a moose.][
]
Mating behaviour
The genus ''Canis'' contains many different species and has a wide range of different mating systems that varies depending on the type of canine and the species. In a study done in 2017 it was found that in some species of canids females use their sexual status to gain food resources. The study looked at wolves and dogs. Wolves
The wolf (''Canis lupus''; plural, : wolves), also known as the gray wolf or grey wolf, is a large Canis, canine native to Eurasia and North America. More than thirty subspecies of Canis lupus, subspecies of ''Canis lupus'' have been reco ...
are typically 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, ...
and form pair-bonds; whereas dogs are promiscuous when free-range and mate with multiple individuals. The study found that in both species females tried to gain access to food more and were more successful in monopolizing a food resource when in heat. Outside of the breeding season their efforts were not as persistent or successful. This shows that the food-for-sex hypothesis likely plays a role in the food sharing among canids and acts as a direct benefit for the females.
Another study on free-ranging dogs found that social factors played a significant role in the determination of mating pairs. The study, done in 2014, looked at social regulation of reproduction in the dogs. They found that females in heat
In thermodynamics, heat is defined as the form of energy crossing the boundary of a thermodynamic system by virtue of a temperature difference across the boundary. A thermodynamic system does not ''contain'' heat. Nevertheless, the term is al ...
searched out dominant males and were more likely to mate with a dominant male who appeared to be a quality leader. The females were more likely to reject submissive males. Furthermore, cases of male-male competition
Sexual selection is a mode of natural selection in which members of one biological sex mate choice, choose mates of the other sex to mating, mate with (intersexual selection), and compete with members of the same sex for access to members of t ...
were more aggressive in the presence of high ranking females. This suggests that females prefer dominant males and males prefer high ranking females meaning social cues and status play a large role in the determination of mating pairs in dogs.
Canids also show a wide range of parental care
Parental care is a behavioural and evolutionary strategy adopted by some animals, involving a parental investment being made to the evolutionary fitness of offspring. Patterns of parental care are widespread and highly diverse across the animal k ...
and in 2018 a study showed that sexual conflict
Sexual conflict or sexual antagonism occurs when the two sexes have conflicting optimal fitness strategies concerning reproduction, particularly over the mode and frequency of mating, potentially leading to an evolutionary arms race between male ...
plays a role in the determination of intersexual parental investment. The studied looked at 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 ...
mating pairs and found that paternal investment was increased to match or near match the maternal investment. The amount of parental care provided by the fathers also was shown to fluctuated depending on the level of care provided by the mother.
Another study on parental investment showed that in free-ranging dogs, mothers modify their energy and time investment into their pups as they age. Due to the high mortality of free-range dogs at a young age a mother's fitness can be drastically reduced. This study found that as the pups aged the mother shifted from high-energy care to lower-energy care so that they can care for their offspring for a longer duration for a reduced energy requirement. By doing this the mothers increasing the likelihood of their pups surviving infancy and reaching adulthood and thereby increase their own fitness.
A study done in 2017 found that aggression between male and female gray wolves varied and changed with age. Males were more likely to chase away rival packs and lone individuals than females and became increasingly aggressive with age. Alternatively, females were found to be less aggressive and constant in their level of aggression throughout their life. This requires further research but suggests that intersexual aggression levels in gray wolves
The wolf (''Canis lupus''; : wolves), also known as the gray wolf or grey wolf, is a large canine native to Eurasia and North America. More than thirty subspecies of ''Canis lupus'' have been recognized, and gray wolves, as popularly un ...
relates to their mating system
A mating system is a way in which a group is structured in relation to sexual behaviour. The precise meaning depends upon the context. With respect to animals, the term describes which males and females mating, mate under which circumstances. Reco ...
.
Tooth breakage
Tooth breakage is a frequent result of carnivores' feeding behaviour.[ Carnivores include both ]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 and solitary hunters. The solitary hunter depends on a powerful bite at the canine teeth to subdue their prey, and thus exhibits a strong mandibular symphysis
In human anatomy, the facial skeleton of the skull the external surface of the mandible is marked in the median line by a faint ridge, indicating the mandibular symphysis (Latin: ''symphysis menti'') or line of junction where the two lateral halves ...
. In contrast, a pack hunter, which delivers many shallower bites, has a comparably weaker mandibular symphysis. Thus, researchers can use the strength of the mandibular symphysis in fossil carnivore specimens to determine what kind of hunter it wasa pack hunter or a solitary hunterand even how it consumed its prey. The mandibles of canids are buttressed behind the carnassial teeth to crack bones with their post-carnassial teeth (molars M2 and M3). A study found that the modern gray wolf and the red wolf (''C.rufus'') possess greater buttressing than all other extant canids and the extinct dire wolf. This indicates that these are both better adapted for cracking bone than other canids.[
A study of nine modern carnivores indicate that one in four adults had suffered tooth breakage and that half of these breakages were of the canine teeth. The highest frequency of breakage occurred in the spotted hyena, which is known to consume all of its prey including the bone. The least breakage occurred in the ]African wild 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 '' Ly ...
. The gray wolf ranked between these two.[ The eating of bone increases the risk of accidental fracture due to the relatively high, unpredictable stresses that it creates. The most commonly broken teeth are the canines, followed by the premolars, carnassial molars, and incisors. Canines are the teeth most likely to break because of their shape and function, which subjects them to bending stresses that are unpredictable in direction and magnitude.][ The risk of tooth fracture is also higher when taking and consuming large prey.][
In comparison to extant gray wolves, the extinct Beringian wolves included many more individuals with moderately to heavily worn teeth and with a significantly greater number of broken teeth. The frequencies of fracture ranged from a minimum of 2% found in the Northern Rocky Mountain wolf ''(Canis lupus irremotus)'' up to a maximum of 11% found in Beringian wolves. The distribution of fractures across the tooth row also differs, with Beringian wolves having much higher frequencies of fracture for incisors, carnassials, and molars. A similar pattern was observed in spotted hyenas, suggesting that increased incisor and carnassial fracture reflects habitual bone consumption because bones are gnawed with the incisors and then cracked with the carnassials and molars.][
]
Coyotes, jackals, and wolves
The gray wolf
The wolf (''Canis lupus''; : wolves), also known as the gray wolf or grey wolf, is a large canine native to Eurasia and North America. More than thirty subspecies of ''Canis lupus'' have been recognized, and gray wolves, as popularly ...
(''C. lupus''), the Ethiopian wolf
The Ethiopian wolf (''Canis simensis''), also called the Simien jackal and Simien fox, is a canine native to the Ethiopian Highlands. In southeastern Ethiopia it is also known as the horse jackal. It is similar to the coyote in size and build, ...
(''C. simensis''), and the African golden wolf
The African wolf (''Canis lupaster'') or golden wolf, formerly known as the African golden jackal, is a canine native to North Africa, West Africa, the Sahel, northern East Africa, and the Horn of Africa. It is listed as least concern on the IU ...
(''C. lupaster'') are three of the many ''Canis'' species referred to as "wolves". Species that are too small to attract the word "wolf" are called 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 ...
s in the Americas
The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World.
Along with th ...
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 elsewhere. Although these may not be more closely related to each other than they are to ''C. lupus'', they are, as fellow ''Canis'' species, more closely related to wolves and domestic dogs than they are to fox
Foxes are small to medium-sized, omnivorous mammals belonging to several genera of the family Canidae. They have a flattened skull, upright, triangular ears, a pointed, slightly upturned snout, and a long bushy tail (or ''brush'').
Twelve sp ...
es, maned wolves
The maned wolf (''Chrysocyon brachyurus'') is a large canine of South America. It is found in Argentina, Brazil, Bolivia, Peru, and Paraguay, and is almost extinct in Uruguay. Its markings resemble those of foxes, but it is neither a fox nor a w ...
, or other canids which do not belong to the genus ''Canis''. The word "jackal" is applied to the golden jackal (''C. aureus''), found across southwestern and south-central Asia, and the Balkans
The Balkans ( ), also known as the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throughout the who ...
in Europe.
African migration
The first record of ''Canis'' on the African continent is ''Canis sp. A'' from South Turkwel, Kenya, dated 3.58–3.2 million years ago. In 2015, a study of mitochondrial genome sequences and whole genome nuclear sequences of African and Eurasian canids indicated that extant wolf-like canids have colonised Africa from Eurasia at least 5 times throughout the Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58[Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...](_blank)
, which is consistent with fossil evidence suggesting that much of the African canid fauna diversity resulted from the immigration of Eurasian ancestors, likely coincident with Plio-Pleistocene climatic oscillations
The Plio-Pleistocene is an informally described geological pseudo-period, which begins about 5 million years ago (Mya) and, drawing forward, combines the time ranges of the formally defined Pliocene and Pleistocene epochs—marking from about 5&nbs ...
between arid and humid conditions. In 2017, the fossil remains of a new ''canis'' species, named ''Canis othmanii'', was discovered among remains found at Wadi Sarrat, Tunisia, from deposits that date 700,000 years ago. This canine shows a morphology more closely associated with canids from Eurasia instead of Africa.
Gallery
File:Canis lupus signatus - 01.jpg, Gray wolf
The wolf (''Canis lupus''; : wolves), also known as the gray wolf or grey wolf, is a large canine native to Eurasia and North America. More than thirty subspecies of ''Canis lupus'' have been recognized, and gray wolves, as popularly ...
(''Canis lupus'')
File:Washtenaw County's last wolf (1907).jpg, Eastern wolf
The eastern wolf (''Canis lycaon'' or ''Canis lupus lycaon'' or ''Canis rufus lycaon'') also known as the timber wolf, Algonquin wolf or eastern timber wolf, is a canine of debated taxonomy native to the Great Lakes region and southeastern Canad ...
(''Canis lycaon'') (includes ''latrans'' admixture)
File:Red wolf (4531335218).jpg, Red wolf
The red wolf (''Canis rufus'') is a canine native to the southeastern United States. Its size is intermediate between the coyote (''Canis latrans'') and gray wolf (''Canis lupus'').
The red wolf's taxonomic classification as being a separate s ...
(''Canis rufus'') (includes ''latrans'' admixture)
File:USMC-11557.jpg, 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 ...
(''Canis latrans'')
File:Golden wolf small.jpg, African golden wolf
The African wolf (''Canis lupaster'') or golden wolf, formerly known as the African golden jackal, is a canine native to North Africa, West Africa, the Sahel, northern East Africa, and the Horn of Africa. It is listed as least concern on the IU ...
(''Canis lupaster'')
File:Flickr - Rainbirder - Golden Jackal.jpg, Eurasian golden jackal (''Canis aureus'')
File:Canis simensis.jpg, Ethiopian wolf
The Ethiopian wolf (''Canis simensis''), also called the Simien jackal and Simien fox, is a canine native to the Ethiopian Highlands. In southeastern Ethiopia it is also known as the horse jackal. It is similar to the coyote in size and build, ...
(''Canis simensis'')
File:Tibetan Wolf By Stanzin (Stakpa).jpg, 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 ...
(''Canis lupus chanco'')
File:Indian Wolf Male.jpg, Indian wolf
The Indian wolf (''Canis lupus pallipes'') is a subspecies of gray wolf that ranges from Southwest Asia to the Indian Subcontinent. It is intermediate in size between the Himalayan wolf and the Arabian wolf, and lacks the former's luxuriant wint ...
(''Canis lupus pallipes'')
File:20110425 German Shepherd Dog 8505.jpg, 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 ...
(''Canis familiaris'')
See also
* List of canids
Canidae is a family of mammals in the order Carnivora, which includes domestic dogs, wolves, coyotes, foxes, jackals, dingoes, and many other extant and extinct dog-like mammals. A member of this family is called a canid; all extant spec ...
References
External links
{{Taxonbar, from=Q149892
Canines
Mammal genera
Extant Tortonian first appearances
Taxa named by Carl Linnaeus