The Bovidae are the biological family of cloven-hoofed, ruminant mammals that includes bison, African buffalo, water buffalo, wildebeest, gazelles, goats and domestic cattle. A member of this family is called a bovid. With 143 extant species and 300 known extinct species, the family Bovidae consists of eight major subfamilies apart from the disputed Peleinae and Pantholopinae; the family evolved 20 million years ago, in the early Miocene. The bovids show great variation in pelage colouration. Excepting some domesticated forms, all male bovids have two or more horns, in many species females possess horns, too; the size and shape of the horns vary but the basic structure is always one or more pairs of simple bony protrusions without branches having a spiral, twisted or fluted form, each covered in a permanent sheath of keratin. Most bovids bear 30 to 32 teeth. Most bovids are diurnal. Social activity and feeding peak during dawn and dusk. Bovids rest before dawn, during midday, after dark, they have various methods of social organisation and social behaviour, which are classified into solitary and gregarious behaviour.
Bovids use different forms of vocal and tangible communication. Most species alternately ruminate throughout the day. While small bovids forage in dense and closed habitat, larger species feed on high-fiber vegetation in open grasslands. Most bovids are polygynous. Mature bovids mate at least once a year and smaller species may mate twice. In some species, neonate bovids remain hidden for a week to two months nursed by their mothers; the greatest diversities of bovids occur in Africa. The maximum concentration of species is in the savannas of eastern Africa. Other bovid species occur in Europe and North America. Bovidae includes three of the five domesticated mammals whose use has spread outside their original ranges, namely cattle and goats. Dairy products such as milk and cheese are manufactured from domestic cattle. Bovids provide leather and wool; the name "Bovidae" was given by the British zoologist John Edward Gray in 1821. The word "Bovidae" is the combination of the prefix bov- and the suffix -idae.
The family Bovidae is placed in the order Artiodactyla. It includes 143 extant species, accounting for nearly 55% of the ungulates, 300 known extinct species. Molecular studies have supported monophyly in the family Bovidae; the number of subfamilies in Bovidae is disputed, with suggestions of as many as ten and as few as two subfamilies. However, molecular and fossil evidence indicates the existence of eight distinct subfamilies: Aepycerotinae, Antilopinae, Caprinae, Cephalophinae and Reduncinae. In addition, three extinct subfamilies are known: Hypsodontinae and the subfamily Tethytraginae, which contains Tethytragus. In 1992, Alan W. Gentry of the Natural History Museum, London divided the eight major subfamilies of Bovidae into two major clades on the basis of their evolutionary history: the Boodontia, which comprised only the Bovinae, the Aegodontia, which consisted of the rest of the subfamilies. Boodonts have somewhat primitive teeth, resembling those of oxen, whereas aegodonts have more advanced teeth like those of goats.
A controversy exists about the recognition of Peleinae and Patholopinae, comprising the genera Pelea and Pantholops as subfamilies. In 2000, American biologist George Schaller and palaeontologist Elisabeth Vrba suggested the inclusion of Pelea in Reduncinae, though the grey rhebok, the sole species of Pelea, is different from kobs and reduncines in morphology. Pantholops, earlier classified in the Antilopinae, was placed in its own subfamily, Pantholopinae; however and morphological analysis supports the inclusion of Pantholops in Caprinae. Below is a cladogram based on Gatesy et Gentry et al.. In the early Miocene, bovids giraffids; the earliest bovids, whose presence in Africa and Eurasia in the latter part of early Miocene has been ascertained, were small animals, somewhat similar to modern gazelles, lived in woodland environments. Eotragus, the earliest known bovid, weighed 18 kg and was nearly the same in size as the Thompson's gazelle. Early in their evolutionary history, the bovids split into two main clades: Boodontia and Aegodontia.
This early split between Boodontia and Aegodontia has been attributed to the continental divide between these land masses. When these continents were rejoined, this barrier was removed, either group expanded into the territory of the other; the tribes Bovini and Tragelaphini diverged in the early Miocene. Bovids are known to have reached the Americas in the Pleistocene by crossing the Bering land bridge; the present genera of Alcelaphinae appeared in the Pliocene. The extinct Alcelaphine genus Paramularius, the same in size as the hartebeest, is believed to have come into being in the Pliocene, but became extinct in the middle Pleistocene. Several genera of Hippotraginae are known
The eastern wolf is a subspecies of gray wolf native to the Great Lakes region and southeastern Canada. The subspecies is the product of ancient genetic admixture between the gray wolf and the coyote, however it is regarded as unique and therefore worthy of conservation. There are two forms, the larger being referred to as the Great Lakes wolf and the smaller being the Algonquin wolf; the eastern wolf's morphology is midway between that of the coyote. The fur is of a grizzled grayish-brown color mixed with cinnamon; the nape and tail region are a mix of black and gray, with the flanks and chest being rufous or creamy. It preys on white-tailed deer, but may attack moose and beavers. In the third edition of Mammal Species of the World published in 2005, the mammalogist W. Christopher Wozencraft listed the eastern wolf as a gray wolf subspecies, which supports its earlier classification based on morphology in three studies; this taxonomic classification has since been debated, with proposals based on DNA analyses that includes a gray wolf ecotype, a gray wolf with genetic introgression from the coyote, a gray wolf/coyote hybrid, a gray wolf/red wolf hybrid, the same species as the red wolf, or a separate species Canis lycaon.
Commencing in 2016, two studies using whole genome sequencing indicate that North American gray wolves and wolf-like canids were the result of ancient and complex gray wolf and coyote mixing, with the Great Lakes wolf possessing 25% coyote ancestry and the Algonquin wolf possessing 40% coyote ancestry. In the US, a bill is before Congress to remove protections under the Endangered Species Act of 1973 for the gray wolf populations located in the western Great Lakes region. In Canada, the eastern wolf is listed as Canis lupus lycaon under the Species At Risk Act 2002, Schedule 1 - List of Wildlife at Risk. In 2015, the Committee on the Status of Endangered Wildlife in Canada recognized the eastern wolf as Canis cf. lycaon and a threatened species worthy of conservation. The main threat to this wolf is human hunting and trapping outside of the protected areas, which leads to genetic introgression with the Eastern coyote due to a lack of mates. Further human development outside of the protected areas and the negative public perception of wolves are expected to inhibit any further expansion of their range.
In 2016, the Committee on the Status of Species at Risk in Ontario recognized the Algonquin wolf as a Canis sp. differentiated from the hybrid Great Lakes wolves and was the result of "hybridization and backcrossing among Eastern Wolf, Gray Wolf, Coyote". The first published name of a taxon belonging to the genus Canis from North America is Canis lycaon, it was published in 1775 by the German naturalist Johann Schreber who had based it on the earlier description and illustration of one specimen, thought to have been captured near Quebec. It was reclassified as a subspecies of gray wolf by Edward Goldman. In the third edition of Mammal Species of the World published in 2005, the mammalogist W. Christopher Wozencraft listed the eastern wolf as a gray wolf subspecies, which supports its earlier classification based on morphology in three studies; this taxonomic classification has since been debated. When European settlers first arrived to North America, the coyote's range was limited to the western half of the continent.
They existed in the arid areas and across the open plains, including the prairie regions of the midwestern states. Early explorers found some in Wisconsin. From the mid-1800s coyotes began expanding beyond their original range; the taxonomic debate regarding North American wolves can be summarised as follows: There are two prevailing evolutionary models for North American Canis: a two-species model that identifies grey wolves and coyotes as distinct species that gave rise to various hybrids, including the Great Lakes-boreal wolf, the eastern coyote, the red wolf and the eastern wolf. The evolutionary biologist Robert K. Wayne, whose team is involved in an ongoing scientific debate with the team led by Linda K. Rutledge, describes the difference between these two evolutionary models: "In a way, it is all semantics, they call it a species, we call it an ecotype." Some of the earliest Canis lupus specimen were discovered at Cripple Creek Sump, Alaska, in strata dated 810,000 years old. The dental measurements of the specimens match historical Canis lupus lycaon specimens from Minnesota.
Mitochondrial DNA can date back thousands of years. In 1991, a study of the mitochondrial DNA sequences of gray wolves and coyotes from across North America found that the gray wolves of the Minnesota and Quebec regions possessed coyote genotypes; the study proposes that dispersing male gray wolves were mating with coyote females in deforested areas bordering wolf territory. The distribution of coyote genotypes within wolves matched the phenotypic differences between these wolves found in an earlier study, with the larger Great Lakes wolf found in Minnesota, the
The domestic yak is a long-haired domesticated bovid found throughout the Himalayan region of the Indian subcontinent, the Tibetan Plateau and as far north as Mongolia and Russia. It is descended from the wild yak; the English word "yak" is a loan originating from Tibetan: Wylie: g.yag. In Tibetan and Balti it refers only to the male of the species, the female being called Tibetan: འབྲི་, Wylie:'bri, or g.nag Tibetan: གནག in Tibetan and Tibetan: ཧཡག་མོ་, Wylie: hYag-mo in Balti. In English, as in most other languages that have borrowed the word, "yak" is used for both sexes, with "bull" or "cow" referring to each sex separately. Yaks are therefore related to cattle. Mitochondrial DNA analyses to determine the evolutionary history of yaks have been inconclusive; the yak may have diverged from cattle at any point between one and five million years ago, there is some suggestion that it may be more related to bison than to the other members of its designated genus. Apparent close fossil relatives of the yak, such as Bos baikalensis, have been found in eastern Russia, suggesting a possible route by which yak-like ancestors of the modern American bison could have entered the Americas.
The species was designated as Bos grunniens by Linnaeus in 1766, but this name is now only considered to refer to the domesticated form of the animal, with Bos mutus being the preferred name for the wild species. Although some authors still consider the wild yak to be a subspecies, Bos grunniens mutus, the ICZN made an official ruling in 2003 permitting the use of the name Bos mutus for wild yaks, this is now the more common usage. Except where the wild yak is considered as a subspecies of Bos grunniens, there are no recognised subspecies of yak. Yaks are built animals with a bulky frame, sturdy legs, rounded cloven hooves, dense, long fur that hangs down lower than the belly. While wild yaks are dark, blackish to brown in colouration, domestic yaks can be quite variable in colour having patches of rusty brown and cream, they have small ears and a wide forehead, with smooth horns that are dark in colour. In males, the horns sweep out from the sides of the head, curve forward, they range from 48 to 99 cm in length.
The horns of females are smaller, only 27 to 64 cm in length, have a more upright shape. Both sexes have a short neck with a pronounced hump over the shoulders, although this is larger and more visible in males. Males weigh 350 to 585 kg, females weigh 225 to 255 kg. Wild yaks can be heavier, bulls reaching weights of up to 1,000 kilograms. Depending on the breed, domestic yak males are 111–138 centimetres high at the withers, while females are 105–117 centimetres high at the withers. Both sexes have long shaggy hair with a dense woolly undercoat over the chest and thighs to insulate them from the cold. In bulls, this may form a long "skirt" that can reach the ground; the tail is horselike rather than tufted like the tails of cattle or bison. Domesticated yaks have a wide range of coat colours, with some individuals being white, brown, roan or piebald; the udder in females and the scrotum in males are hairy, as protection against the cold. Females have four teats. Yaks grunt and, unlike cattle, are not known to produce the characteristic bovine lowing sound, which inspired the scientific name of the domestic yak variant, Bos grunniens.
Nikolay Przhevalsky named the wild variant Bos mutus. Yak physiology is well adapted to high altitudes, having larger lungs and heart than cattle found at lower altitudes, as well as greater capacity for transporting oxygen through their blood due to the persistence of foetal haemoglobin throughout life. Conversely, yaks have trouble thriving at lower altitudes, are prone to suffering from heat exhaustion above about 15 °C. Further adaptations to the cold include a thick layer of subcutaneous fat, an complete lack of functional sweat glands. Compared with domestic cattle, the rumen of yaks is unusually large, relative to the omasum; this allows them to consume greater quantities of low-quality food at a time, to ferment it longer so as to extract more nutrients. Yak consume the equivalent of 1% of their body weight daily while cattle require 3% to maintain condition. Contrary to popular belief and their manure have little to no detectable odour when maintained appropriately in pastures or paddocks with adequate access to forage and water.
Yak's wool is odour resistant. Yaks mate in the summer between July and September, depending on the local environment. For the remainder of the year, many bulls wander in small bachelor groups away from the large herds, but, as the rut approaches, they become aggressive and fight among each other to establish dominance. In addition to non-violent threat displays and scraping the ground with their horns, bull yaks compete more directly charging at each other with heads lowered or sparring with their horns. Like bison, but unlike cattle, males wallow in dry soil during the rut while scent-marking with urine or dung. Females enter oestrus up to four times a year, females are receptive only for a few hours in each cycle. Gestation lasts between 257 and 270 days, so that the young are born between May and June, results in the birth of a single calf; the cow finds a secluded spot to give birth, but the calf is able to walk within about ten minutes of birth
The eastern coyote is a wild North American canine of mixed coyote-wolf and dog parentage. The hybridization first occurred in the Great Lakes region, as western coyotes moved east, it was first noticed during the early 1930s to the late 1940s, originated in the aftermath of the extirpation of the gray wolf in southeastern Ontario and Quebec, thus allowing coyotes to colonize the former wolf ranges and mix with the remnant wolf populations. This hybrid is smaller than the eastern wolf and holds smaller territories, but is larger and holds more extensive home ranges than the typical western coyote; the canid has been referred to in scientific publications as Canis latrans, Canis latrans var, Canis latrans × Canis lycaon, has been referred to as the eastern coyote, northeastern coyote, coywolf. It is called the southern tweed wolf. Coyotes and wolves first hybridized in the Great Lakes region, followed by a hybrid coyote expansion that created the largest mammalian hybrid zone known. In 2014, a DNA study of northeastern coyotes showed them on average to be a hybrid of western coyote, western wolf, eastern wolf, domestic dog in their nuclear genome.
The hybrid swarm extended into the midwestern United States, with Ohio coyotes shown on average to be a hybrid of western coyote, western wolf, eastern wolf, domestic dog in their nuclear genome. For northeastern coyotes, hybridization with the dog was estimated to have occurred between 11 and 24 generations ago, there is no evidence of recent dog-coyote crossing. There was some evidence of first and second generation wolf-coyote hybrids back-crossing with coyotes. For Ohio coyotes, the wolf DNA was present in the nuclear genome but not the mitochondrial genome, indicating hybridization between male wolves and female coyotes. For northeastern coyotes, the dog DNA was present in the nuclear genome but not the mitochondrial genome, indicating hybridization between male dogs and female coyotes. Although hundreds of northeastern coyotes showed maternal wolf DNA, nearly all were the same haplotype that indicated a past single hybridization between a female wolf and a male coyote; these findings support the hypothesis of sexual interaction based on body size, with the larger species male always crossing with the smaller species female.
Northeast coyotes benefit from a more diverse genome that includes genes from both wolves and dogs, which has allowed their adaption to both forested and human-dominated habitats. Coyotes moved into the northeast after they began to hybridize with wolves between 154 and 190 years ago. Coyotes are more genetically wolf-like in areas where a high deer density exists, supporting the theory that introgression from wolves allowed genetic adaption to this food source. There are an estimated 16–20 million white-tailed deer in the United States, their overpopulation is estimated to cause $2 billion in damage each year, with $1 billion in automobile damage alone. Management practices should consider the ecological value of large predators in maintaining their balance. In 2016, a proposal was made to recognize the eastern coyote as a separate species due to its morphologic and genetic distinctiveness. Additionally, it has bred with other northeast coyotes across the majority of its range, without further hybridization with parent species, except for on the edges of this range.
Its range includes areas. The designation Canis oriens has been proposed in place of the unwieldy Canis latrans × Canis lycaon × Canis lupus. Adult eastern coyotes are larger than western coyotes, weighing an average of 14–18 kilograms, with female eastern coyotes weighing 21% more than male western coyotes. Eastern coyotes weigh more at birth, 349–360 grams to 250–300 grams. By 35 days of age eastern coyote pups average 1,590 grams, 200 grams more than western pups. After this, physical differences become more apparent, with eastern coyote pups displaying longer legs. Differences in dental development have been observed, with tooth eruption beginning and in a different order. There are no significant differences between eastern and western coyote pups in expressions of aggression and fighting, though eastern coyotes tend to fight less and are more playful. Unlike western pups, in which fighting precedes play behavior, fighting among east pups occurs after the onset of play. Eastern coyotes tend to reach sexual maturity when they reach two years of age, much than western coyotes.
Aside from size, both eastern and western coyotes are physically similar. The eastern has four color phases, ranging from dark brown to blond or reddish blond, with gray-brown the most common, reddish legs and flanks; the eastern coyote is present in New England, New York, New Jersey, Pennsylvania, West Virginia, Maryland and Virginia. They range in the eastern Canadian provinces of Ontario, New Brunswick, Nova Scotia, Prince Edward Island, Newfoundland and Labrador. Eastern coyotes are opportunistic omnivores and will prey on whatever is available and easy to scavenge or kill. Though they are known to take anything from mice to moose, the Ontario Ministry of Natural Resources lists their main prey items as rabbits and deer in the winter and small mammals, wild berries, birds and grasshoppers in the summer, their diet shifts with the changing seasons. It can include, but is not limited to, insects and berries during summer and small mammals in the fall and winter; as winter becomes harder in the season, larger
Żubroń is a hybrid of domestic cattle and wisent. The wisent is the European bison; the name żubroń was chosen from hundreds of proposals sent to the Polish weekly magazine Przekrój during a contest organised in 1969. The żubroń was first created by Leopold Walicki in 1847, although the hybrid may have appeared at an earlier time. After World War I, various scientists considered żubroń a possible replacement for domestic cattle. Żubroń turned out to be less susceptible to disease. In addition, the animal could be bred on marginal grazing land with no farm infrastructure and with minimal husbandry in huge state agricultural farms. From 1958, the work on żubroń herds was continued by the Polish Academy of Sciences in various laboratories, most notably in Białowieża and Młodzikowo. During the first 16 years of experiments, a total of 71 animals were born, including Filon, the first żubroń born to a żubroń mother; the animal was intended to become a cheap alternative to cattle. The experiment was continued until the late 1980s, when the results of the breeding programmes were deemed unsatisfactory.
Various factors contributed to this decision, including the severe economic difficulties of the Polish socialist economy in the 1980s, a lack of interest from the notoriously ineffective SAFs, fears that żubroń would crossbreed with the endangered wild wisent, contaminating their gene pool. The two notable centres for experiments on the species were Łękno and Popielno, while limited experiments were held in the reserve of Askania Nova in the USSR; this was discontinued, the sole surviving herd consists of several animals only, kept at Bialowieski National Park. As of 2007, there are press releases suggesting the breeding and experiments are continuing in Karolew in Greater Poland. Żubroń are heavy animals, with males weighing up to females up to 810 kg. They are strong, resistant to disease, tolerant of harsh weather conditions; the first-cross calves have to be born by Caesarean section, because although they may be carried to full term, parturition never occurs. Males are infertile in the first generation.
Females are fertile and can be crossbred with either parent species, i.e. with cattle or wisent, males from these backcrosses are fertile. Beefalo Dzo Haldane's rule
Felidae is a family of mammals in the order Carnivora, colloquially referred to as cats. A member of this family is called a felid; the term "cat" refers both to felids in general and to the domestic cat. The Felidae species exhibit the most diverse fur pattern of all terrestrial carnivores. Cats have slender muscular bodies and strong flexible forelimbs, their teeth and facial muscles allow for a powerful bite. They are all obligate carnivores, most are solitary predators ambushing or stalking their prey. Wild cats occur in Africa, Europe and the Americas; some wild cat species are adapted to forest habitats, some to arid environments, a few to wetlands and mountainous terrain. Their activity patterns range from nocturnal and crepuscular to diurnal, depending on their preferred prey species. Reginald Innes Pocock divided the extant Felidae into three subfamilies: the Pantherinae, the Felinae and the Acinonychinae, differing from each other by the ossification of the hyoid apparatus and by the cutaneous sheaths which protect their claws.
This concept has been revised following developments in molecular biology and techniques for analysis of morphological data. Today, the living Felidae are divided in two subfamilies, with the Pantherinae including seven Panthera and two Neofelis species; the Felinae include all the non-pantherine cats with 34 species. The first cats emerged during the Oligocene about 25 million years ago, with the appearance of Proailurus and Pseudaelurus; the latter species complex was ancestral to two main lines of felids: the cats in the extant subfamilies and a group of extinct cats of the subfamily Machairodontinae, which include the saber-toothed cats such as the Smilodon. The "false sabre toothed cats", the Barbourofelidae and Nimravidae, are not true cats, but are related. Together with the Felidae, Viverridae and mongooses, they constitute the Feliformia. All members of the cat family have the following characteristics in common: They are digitigrade, have five toes on their forefeet and four on their hind feet.
Their curved claws are protractile and attached to the terminal bones of the toe with ligaments and tendons. The claws are guarded except in the Acinonyx, they protract the claws by contracting muscles in the toe, they passively retract them. The dewclaws do not protract, they have 30 teeth with a dental formula of 22.214.171.124.1.2.1. The upper third premolar and lower molar are adapted as carnassial teeth, suited to tearing and cutting flesh; the canine teeth are large. The lower carnassial is smaller than the upper carnassial and has a crown with two compressed blade-like pointed cusps, their nose projects beyond the lower jaw. They have well developed and sensitive whiskers above the eyes, on the cheeks, on the muzzle, but not below the chin. Whiskers help to capture and hold prey, their skull is foreshortened with large orbits. Their tongue is covered with horny papillae, which rasp meat from aid in grooming, their eyes are large, situated to provide binocular vision. Their night vision is good due to the presence of a tapetum lucidum, which reflects light back inside the eyeball, gives felid eyes their distinctive shine.
As a result, the eyes of felids are about six times more light sensitive than those of humans, many species are at least nocturnal. The retina of felids contains a high proportion of rod cells, adapted for distinguishing moving objects in conditions of dim light, which are complemented by the presence of cone cells for sensing colour during the day, their external ears are large, sensitive to high-frequency sounds in the smaller cat species. This sensitivity allows them to locate small rodent prey, they have flexible bodies with muscular limbs. The plantar pads of both fore and hind feet form compact three-lobed cushions; the penis is boneless. Relative to body size, they have shorter bacula than canids, they can not detect the sweetness of sugar. Felids have a vomeronasal organ in the roof of the mouth; the use of this organ is associated with the Flehmen response. The standard sounds made by all felids include meowing, hissing and growling. Meowing is the main contact sound, they can purr during both phases of respiration, though pantherine cats seem to purr only during oestrus and copulation, as cubs when suckling.
Purring is a low pitch sound of less than 2 kHz and mixed with other vocalization types during the expiratory phase. Most felids are able to land on their feet after a fall due to the cat righting reflex; the colour and density of their fur is diverse. Fur colour varies from light brown to golden and reddish brown, fur pattern from distinctive small spots, stripes to small blotches and rosettes. Most cat species are born except the jaguarundi, Asian golden cat and caracal; the spotted fur of lion and cougar cubs change to a uniform fur during their ontogeny. Those living in cold environments have thick fur with long hair, like the snow leopard and the Pallas's cat; those living in tropical and hot climate zones have short fur. Several species exhibit melanism with all-black individuals. In the great majority of cat species, the tail is between a third and a half of the body length, although with some exceptions, like the Ly
Coywolf is an informal term for a canid hybrid descended from coyotes, eastern wolves and gray wolves. All members of the genus Canis are genetically related because their chromosomes number 78, therefore they can interbreed. One genetic study indicates that these two species genetically diverged recently. Genomic studies indicate that nearly all North American gray wolf populations possess some degree of admixture with coyotes following a geographic cline, with the lowest levels occurring in Alaska, the highest in Ontario and Quebec, as well as Atlantic Canada. Hybrids of any combination tend to be smaller than wolves. In one captive hybrid experiment, six F1 hybrid pups from a male northwestern gray wolf and a female coyote were measured shortly after birth with an average on their weights, total lengths, head lengths, body lengths, hind foot lengths, shoulder circumferences, head circumferences compared with those on pure coyote pups at birth. Despite being delivered by a female coyote, the hybrid pups at birth were much larger and heavier than regular coyote pups born and measured around the same time.
At six months of age, these hybrids were monitored at the Wildlife Science Center. Executive Director Peggy Callahan at the facility states that the howls of these hybrids are said to start off much like regular gray wolves with a deep strong vocalization, but changes partway into a coyote-like high pitched yipping. Compared with pure coyotes, eastern wolf-coyote hybrids form more cooperative social groups and are less aggressive with each other while playing. Hybrids reach sexual maturity when they are two years old, much than occurs in pure coyotes. Eastern coyotes range from New England, New York, New Jersey, Pennsylvania, West Virginia, Maryland and Virginia, their range occurs in the Canadian provinces of Ontario, New Brunswick, Nova Scotia, Prince Edward Island and Newfoundland and Labrador. Coyotes and wolves hybridized in the Great Lakes region, followed by an eastern coyote expansion, creating the largest mammalian hybrid zone known. Extensive hunting of gray wolves over a period of 400 years caused a population decline that reduced the number of suitable mates, thus facilitating coyote genes swamping into the eastern wolf population.
This has caused concern over the purity of remaining wolves in the area, the resulting eastern coyotes are too small to substitute for pure wolves as apex predators of moose and deer. The main nucleus of pure eastern wolves is concentrated within Algonquin Provincial Park; this susceptibility to hybridization led to the eastern wolf being listed as Special Concern under the Canadian Committee on the Status of Endangered Wildlife and with the Committee on the Status of Species at Risk in Ontario. By 2001, protection was extended to eastern wolves occurring on the outskirts of the park, thus no longer depriving Park eastern wolves of future pure-blooded mates. By 2012, the genetic composition of the park's eastern wolves was restored to what it was in the mid-1960s, rather than in the 1980s–1990s, when the majority of wolves had large amounts of coyote DNA. Aside from the combinations of coyotes and eastern wolves making up most of the modern day eastern coyote's gene pools, some of the coyotes in the northeastern United States have mild domestic dog and western Great Plains gray wolf influences in their gene pool, thus suggesting that the eastern coyote is a four-in-one hybrid of coyotes, eastern wolves, western gray wolves, dogs, that the hybrids living in areas with higher white-tailed deer density have higher degrees of wolf genes than those living in urban environments.
The addition of domestic dog genes may have played a minor role in facilitating the eastern hybrids' adaptability to survive in human-developed areas. The four-in-one hybrid theory was further explored in 2014, when Monzón and his team subsequently reanalyzed the tissue and SNP samples taken from 425 eastern coyotes to determine the degree of wolf and dog introgressions involved in each geographic range; the domestic dog allele averages 10% of the eastern coyote's genepool, while 26% is contributed by a cluster of both eastern wolves and western gray wolves. The remaining 64% matched with coyotes; this analysis suggested that prior to the uniformity of its modern-day genetic makeup, multiple swarms of genetic exchanges between the coyotes, feral dogs, the two distinct wolf populations present in the Great Lakes region may have occurred, urban environments favor coyote genes, while the ones in the rural and deep forest areas maintain higher levels of wolf content. A 2016 meta-analysis of 25 genetics studies from 1995–2013 found that the northeastern coywolf is 60% western coyote, 30% eastern wolf, 10% domestic dog.
However, this hybrid canid is only now coming into contact with the southern wave of coyote migration into the southern United States. The taxonomy of the red and eastern wolf of the Southeastern United States and the Great Lakes region has been long debated, with various schools of thought advocating that they represent either unique species or results of varying degrees of gray wolf-coyote admixture. In May 2011, an examination of 48,000 single nucleotide polymorphisms in red wolves, eastern wolves, gray wolves, dogs indicated that the red and eastern wolves were hybrid species, with the red wolf being 76% coyote and only 20% gray wolf, the eastern wolf being 58% gray wolf and 42% coyote, finding no evidence of being distinct species in either; the study was crit