Crepuscular animals are those that are active during twilight. This is distinguished from diurnal and nocturnal behavior, where an animal is active during the hours of daylight or the hours of darkness, respectively; the term is not precise, however, as some crepuscular animals may be active on a moonlit night or during an overcast day. The term matutinal is used for animals that are active only before sunrise, vespertine for those active only after sunset; the time of day an animal is active depends on a number of factors. Predators need to link their activities to times of day at which their prey is available, prey try to avoid the times when their principal predators are at large; the temperature at midday may be too high or at night too low. Some creatures may adjust their activities depending on local competition. Therefore, for many varied reasons, crepuscular activity may best meet an animal's requirements by compromise; the word crepuscular derives from the Latin crepusculum. Its sense accordingly differs from diurnal and nocturnal behavior, which peak during hours of daylight and darkness.
The distinction is not absolute however, because crepuscular animals may be active on a bright moonlit night or on a dull day. Some animals casually described. Special classes of crepuscular behaviour include matutinal and vespertine, denoting species active only in the dawn or only in the dusk, respectively; those that are active during both morning and evening twilight are said to have a bimodal activity pattern. The various patterns of activity are thought to be antipredator adaptations, though some could well be predatory adaptations. Many predators forage most intensively at night, whereas others are active at midday and see best in full sun. Thus, the crepuscular habit may both reduce predation pressure, thereby increasing the crepuscular populations, in consequence offer better foraging opportunities to predators that focus their attention on crepuscular prey until a new balance is struck; such shifting states of balance are found in ecology. Some predatory species adjust their habits in response to competition from other predators.
For example, the subspecies of short-eared owl that lives on the Galápagos Islands is active during the day, but on islands like Santa Cruz that are home to the Galapagos hawk, the owl is crepuscular. Apart from the relevance to predation, crepuscular activity in hot regions may be the most effective way of avoiding heat stress while capitalizing on available light. Many familiar mammal species are crepuscular, including some bats, housecats, stray dogs, ferrets, guinea pigs and rats. Other crepuscular mammals include jaguars, bobcats, red pandas, deer, sitatunga, chinchillas, the common mouse, squirrels, Australian wombats, quolls and marsupial gliders, spotted hyenas, African wild dogs. Snakes and lizards those in desert environments, may be crepuscular. Crepuscular birds include the common nighthawk, barn owl, owlet-nightjar, chimney swift, American woodcock, spotted crake, white-breasted waterhen. Many moths, beetles and other insects are crepuscular and vespertine. Cathemeral Crypsis Diurnality Nocturnality
Feces are the solid or semisolid remains of the food that could not be digested in the small intestine. Bacteria in the large intestine further break down the material. Feces contain a small amount of metabolic waste products such as bacterially altered bilirubin, the dead epithelial cells from the lining of the gut. Feces are discharged through cloaca during a process called defecation. Feces can be used as soil conditioner in agriculture, it can be burned and used as a fuel source or dried and used as a construction material. Some medicinal uses have been found. In the case of human feces, fecal transplants or fecal bacteriotherapy are in use. Urine and feces together are called excreta; the distinctive odor of feces is due to bacterial action. Gut flora produces compounds such as indole and thiols, as well as the inorganic gas hydrogen sulfide; these are the same compounds. Consumption of foods prepared with spices may result in the spices being undigested and adding to the odor of feces; the perceived bad odor of feces has been hypothesized to be a deterrent for humans, as consuming or touching it may result in sickness or infection.
Human perception of the odor may be contrasted by a non-human animal's perception of it. Feces are discharged through cloaca during a process called defecation; this process requires pressures that may reach 100 mm Hg in 450 mm Hg in penguins. The forces required to expel the feces are generated through muscular contractions and a build-up of gases inside the gut, prompting the sphincter to relieve the pressure on it and to release the feces. After an animal has digested eaten material, the remains of that material are discharged from its body as waste. Although it is lower in energy than the food from which it is derived, feces may retain a large amount of energy 50% of that of the original food; this means that of all food eaten, a significant amount of energy remains for the decomposers of ecosystems. Many organisms feed on feces, from bacteria to fungi to insects such as dung beetles, who can sense odors from long distances; some may specialize in feces. Feces serve not only as a basic food, but as a supplement to the usual diet of some animals.
This process is known as coprophagia, occurs in various animal species such as young elephants eating the feces of their mothers to gain essential gut flora, or by other animals such as dogs and monkeys. Feces and urine, which reflect ultraviolet light, are important to raptors such as kestrels, who can see the near ultraviolet and thus find their prey by their middens and territorial markers. Seeds may be found in feces. Animals who eat fruit are known as frugivores. An advantage for a plant in having fruit is that animals will eat the fruit and unknowingly disperse the seed in doing so; this mode of seed dispersal is successful, as seeds dispersed around the base of a plant are unlikely to succeed and are subject to heavy predation. Provided the seed can withstand the pathway through the digestive system, it is not only to be far away from the parent plant, but is provided with its own fertilizer. Organisms that subsist on dead organic matter or detritus are known as detritivores, play an important role in ecosystems by recycling organic matter back into a simpler form that plants and other autotrophs may absorb once again.
This cycling of matter is known as the biogeochemical cycle. To maintain nutrients in soil it is therefore important that feces return to the area from which they came, not always the case in human society where food may be transported from rural areas to urban populations and feces disposed of into a river or sea. Depending on the individual and the circumstances, human beings may defecate several times a day, every day, or once every two or three days; the extensive hardening that interrupts this routine for several days or more is called constipation. The appearance of human fecal matter varies according to health, it is semisolid, with a mucus coating. A combination of bile and bilirubin, which comes from dead red blood cells, gives feces the typical brown color. After the meconium, the first stool expelled, a newborn's feces contain only bile, which gives it a yellow-green color. Breast feeding babies expel soft, pale yellowish, not quite malodorous matter. At different times in their life, human beings will expel feces of different textures.
A stool that passes through the intestines will look greenish. The feces of animals are used as fertilizer. Dry animal dung is used as a fuel source in many countries around the world; some animal feces that of camel and cattle, are fuel sources when dried. Animals such as the giant panda and zebra possess gut bacteria capable of producing biofuel; that bacteria, called Brocadia anammoxidans, can create the rocket fuel hydrazine. A coprolite is classified as a trace fossil. In paleontology they give evidence about the diet of an animal, they were first described by William Buckland in 1829. Prior to this they were known as "fossil fir cones" and "bezoar stones", they serve a valuable purpose in paleontology because they provide direct evidence of the predation and diet of extinct organisms. Coprolites may range in size from a few millimetres to more than 60 centimetres. Palaeofeces are ancie
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
A chordate is an animal constituting the phylum Chordata. During some period of their life cycle, chordates possess a notochord, a dorsal nerve cord, pharyngeal slits, an endostyle, a post-anal tail: these five anatomical features define this phylum. Chordates are bilaterally symmetric; the Chordata and Ambulacraria together form the superphylum Deuterostomia. Chordates are divided into three subphyla: Vertebrata. There are extinct taxa such as the Vetulicolia. Hemichordata has been presented as a fourth chordate subphylum, but now is treated as a separate phylum: hemichordates and Echinodermata form the Ambulacraria, the sister phylum of the Chordates. Of the more than 65,000 living species of chordates, about half are bony fish that are members of the superclass Osteichthyes. Chordate fossils have been found from as early as the Cambrian explosion, 541 million years ago. Cladistically, vertebrates - chordates with the notochord replaced by a vertebral column during development - are considered to be a subgroup of the clade Craniata, which consists of chordates with a skull.
The Craniata and Tunicata compose the clade Olfactores. Chordates form a phylum of animals that are defined by having at some stage in their lives all of the following anatomical features: A notochord, a stiff rod of cartilage that extends along the inside of the body. Among the vertebrate sub-group of chordates the notochord develops into the spine, in wholly aquatic species this helps the animal to swim by flexing its tail. A dorsal neural tube. In fish and other vertebrates, this develops into the spinal cord, the main communications trunk of the nervous system. Pharyngeal slits; the pharynx is the part of the throat behind the mouth. In fish, the slits are modified to form gills, but in some other chordates they are part of a filter-feeding system that extracts particles of food from the water in which the animals live. Post-anal tail. A muscular tail that extends backwards behind the anus. An endostyle; this is a groove in the ventral wall of the pharynx. In filter-feeding species it produces mucus to gather food particles, which helps in transporting food to the esophagus.
It stores iodine, may be a precursor of the vertebrate thyroid gland. There are soft constraints that separate chordates from certain other biological lineages, but are not part of the formal definition: All chordates are deuterostomes; this means. All chordates are based on a bilateral body plan. All chordates are coelomates, have a fluid filled body cavity called a coelom with a complete lining called peritoneum derived from mesoderm; the following schema is from the third edition of Vertebrate Palaeontology. The invertebrate chordate classes are from Fishes of the World. While it is structured so as to reflect evolutionary relationships, it retains the traditional ranks used in Linnaean taxonomy. Phylum Chordata †Vetulicolia? Subphylum Cephalochordata – Class Leptocardii Clade Olfactores Subphylum Tunicata – Class Ascidiacea Class Thaliacea Class Appendicularia Class Sorberacea Subphylum Vertebrata Infraphylum incertae sedis Cyclostomata Superclass'Agnatha' paraphyletic Class Myxini Class Petromyzontida or Hyperoartia Class †Conodonta Class †Myllokunmingiida Class †Pteraspidomorphi Class †Thelodonti Class †Anaspida Class †Cephalaspidomorphi Infraphylum Gnathostomata Class †Placodermi Class Chondrichthyes Class †Acanthodii Superclass Osteichthyes Class Actinopterygii Class Sarcopterygii Superclass Tetrapoda Class Amphibia Class Sauropsida Class Synapsida Craniates, one of the three subdivisions of chordates, all have distinct skulls.
They include the hagfish. Michael J. Benton commented that "craniates are characterized by their heads, just as chordates, or all deuterostomes, are by their tails". Most craniates are vertebrates; these consist of a series of bony or cartilaginous cylindrical vertebrae with neural arches that protect the spinal cord, with projections that link the vertebrae. However hagfish have incomplete braincases and no vertebrae, are therefore not regarded as vertebrates, but as members of the craniates, the group from which vertebrates are thought to have evolved; however the cladistic exclusion of hagfish from the vertebrates is controversial, as they ma
The black-backed jackal is a canid native to two areas of Africa, separated by 900 km. One region includes the southernmost tip of the continent, including South Africa, Namibia and Zimbabwe; the other area is along the eastern coastline, including Kenya, Djibouti and Ethiopia. It is listed by the IUCN as least concern, due to its widespread range and adaptability, although it is still persecuted as a livestock predator and rabies vector. Compared to other members of the genus Canis, the black-backed jackal is a ancient species, has changed little since the Pleistocene, being the most basal wolf-like canine, alongside the related side-striped jackal, it is a fox-like animal with a reddish coat and a black saddle that extends from the shoulders to the base of the tail. It is a monogamous animal, whose young may remain with the family to help raise new generations of pups; the black-backed jackal is not a fussy eater, feeds on small to medium-sized animals, as well as plant matter and human refuse.
The species is known by several different names, including saddle-backed, silver-backed and golden jackal. The Latin mesomelas is a compound consisting of meso and melas; the black-backed jackal has occupied eastern and southern Africa for at least 2-3 million years, as shown by fossil deposits in Kenya and South Africa. Specimens from fossil sites in Transvaal are identical to their modern counterparts, but have different nasal bones; as no fossils have been found north of Ethiopia, the species has always been sub-Saharan in distribution. The black-backed jackal is unspecialised, can thrive in a wide variety of habitats, including deserts, as its kidneys are well adapted for water deprivation, it is, more adapted to a carnivorous diet than the other jackals, as shown by its well-developed carnassial shear and the longer cutting blade of the premolars. Juliet Clutton-Brock classed the black-backed jackal as being related to the side-striped jackal, based on cranial and dental characters. Studies on allozyme divergence within the Canidae indicate that the black-backed jackal and other members of the genus Canis are separated by a considerable degree of genetic distance.
Further studies show a large difference in mitochondrial DNA sequences between black-backed jackals and other sympatric "jackal" species, consistent with divergence 2.3–4.5 million years ago. A mitochondrial DNA sequence alignment for the wolf-like canids gave a phylogenetic tree with the side-striped jackal and the black-backed jackal being the most basal members of this clade, which means that this tree is indicating an African origin for the clade; because of this deep divergence between the black-backed jackal and the rest of the "wolf-like" canids, one author has proposed to change the species' generic name from Canis to Lupulella. In 2017, jackal relationships were further explored, with an mDNA study finding that the two black-backed jackal subspecies had diverged from each other 1.4 million years ago to form the central African and east African populations. The study proposes that due to this long separation, longer than the separation of the African golden wolf from the wolf lineage, that the two subspecies might warrant separate species status.
See further:Canis evolution Two subspecies are recognised by MSW3. These subspecies are geographically separated by a gap which extends northwards from Zambia to Tanzania: The black-backed jackal is a fox-like canid with a slender body, long legs, large ears, it is similar to the related side-striped jackal and more distantly related to the golden jackal, though its skull and dentition are more robust and the incisors much sharper. It weighs 6–13 kg, stands 38–48 cm at the shoulder, measures 67.3–81.2 cm in body length. The base colour is reddish brown to tan, pronounced on the flanks and legs. A black saddle intermixed. A long, black stripe extending along the flanks separates the saddle from the rest of the body, can be used to differentiate individuals; the tail is tipped with black. The lips, throat and inner surface of the limbs are white; the winter coat is a much deeper reddish brown. Albino specimens occur; the hair of the face measures 10–15 mm in length, lengthens to 30–40 mm on the rump.
The guard hairs of the back are 60 mm on the shoulder, decreasing to 40 mm at the base of the tail. The hairs of the tail are the longest; the black-backed jackal is a monogamous and territorial animal, whose social organisation resembles that of the golden jackal. However, the assistance of elder offspring in helping raise the pups of their parents has a greater bearing on pup survival rates than in the latter species; the basic social unit is a monogamous mated pair which defends its territory through laying faeces and urine on range boundaries. Scent marking is done in tandem, the pair aggressively expels intruders; such encounters are prevented, as the pair vocalises to advertise its presence in a given area. It is a vocal species in Southern Africa. Sounds made by the species include yelling, woofing, whining and cackling, it communicates with group members and advertises its presence by a high-pitched, whining howl, expresses alarm through an explosive cry followed by shorter, high-pitched yelps.
This sound is frantic when mobbing a leopard. In areas where the black-backed jackal is sympatric with the African golden wolf, the species does not howl, instead relying
The wolf known as the grey/gray wolf or timber wolf, is a canine native to the wilderness and remote areas of Eurasia and North America. It is the largest extant member of its family, with males averaging 43 -- females 36 -- 38.5 kg. It is distinguished from other Canis species by its larger size and less pointed features on the ears and muzzle, its winter fur is long and bushy and predominantly a mottled gray in color, although nearly pure white and brown to black occur. Mammal Species of the World, a standard reference work in zoology, recognises 38 subspecies of C. lupus. The gray wolf is the second most specialized member of the genus Canis, after the Ethiopian wolf, as demonstrated by its morphological adaptations to hunting large prey, its more gregarious nature, its advanced expressive behavior, it is nonetheless related enough to smaller Canis species, such as the coyote, golden jackal, to produce fertile hybrids. It is the only species of Canis to have a range encompassing both Eurasia and North America, originated in Eurasia during the Pleistocene, colonizing North America on at least three separate occasions during the Rancholabrean.
It is a social animal, travelling in nuclear families consisting of a mated pair, accompanied by the pair's adult offspring. The gray wolf is an apex predator throughout its range, with only humans and tigers posing a serious threat to it, it feeds on large ungulates, though it eats smaller animals, livestock and garbage. A seven-year-old wolf is considered to be old, the maximum lifespan is about 16 years; the global gray wolf population is estimated to be 300,000. The gray wolf is one of the world's best-known and most-researched animals, with more books written about it than any other wildlife species, it has a long history of association with humans, having been despised and hunted in most pastoral communities because of its attacks on livestock, while conversely being respected in some agrarian and hunter-gatherer societies. Although the fear of wolves is pervasive in many human societies, the majority of recorded attacks on people have been attributed to animals suffering from rabies. Non-rabid wolves have attacked and killed people children, but this is rare, as wolves are few, live away from people, have developed a fear of humans from hunters and shepherds.
The English'wolf' stems from the Old English wulf, itself thought to be derived from the Proto-Germanic *wulfaz. The Latin lupus is a Sabine loanword. Both derive from the Proto-Indo-European root * lukwos; the species Canis lupus was first recorded by Carl Linnaeus in his publication Systema Naturae in 1758, with the Latin classification translating into the English words "dog wolf". The 37 subspecies of Canis lupus are listed under the designated common name of "wolf" in Mammal Species of the World, published in 2005; the nominate subspecies is the Eurasian wolf known as the common wolf. The subspecies includes the domestic dog, eastern wolf and red wolf, but lists C. l. italicus as a synonym of C. l. lupus. However, the classification of several as either species or subspecies has been challenged; the evolution of the wolf occurred over a geologic time scale of at least 300,000 years. The gray wolf Canis lupus is a adaptable species, able to exist in a range of environments and which possesses a wide distribution across the Holarctic.
Studies of modern gray wolves have identified distinct sub-populations that live in close proximity to each other. This variation in sub-populations is linked to differences in habitat – precipitation, temperature and prey specialization – which affect cranio-dental plasticity; the archaeological and paleontological records show gray wolf continuous presence for at least the last 300,000 years. This continuous presence contrasts with genomic analyses, which suggest that all modern wolves and dogs descend from a common ancestral wolf population that existed as as 20,000 years ago; these analyses indicate a population bottleneck, followed by a rapid radiation from an ancestral population at a time during, or just after, the Last Glacial Maximum. However, the geographic origin of this radiation is not known. In 2018, whole genome sequencing was used to compare members of the genus Canis, along with the dhole and the African hunting dog. There is evidence of gene flow between African golden wolves, golden jackals, gray wolves.
One African golden wolf from the Egyptian Sinai Peninsula showed high admixture with the Middle Eastern gray wolves and dogs, highlighting the role of the land bridge between the African and Eurasian continents in canid evolution. There was evidence of gene flow between golden jackals and Middle Eastern wolves, less so with European and Asian wolves, least with North American wolves; the study proposes that the golden jackal ancestry found in North American wolves may have occurred before the divergence of the Eurasian and North American gray wolves. The study indicates that the common ancestor of the coyote and gray wolf has genetically admixed with a ghost population of an extinct unidentified canid; the canid is genetically close to the dhole and has evolved after the divergence of the African hunting dog from the other canid species. The basal position of the coyote compared to the wolf is proposed to be due to the coyote retaining more of the mitochondrial genome of this unknown canid.
In 2013, a genetic study found that the wolf population in Europe was divided along a north-south axis and formed five major clusters. Three clusters were identified occupying southern and
The Ethiopian wolf is a canid native to the Ethiopian Highlands. It is similar to the coyote in size and build, is distinguished by its long and narrow skull, its red and white fur. Unlike most large canids, which are widespread, generalist feeders, the Ethiopian wolf is a specialised feeder of Afroalpine rodents with specific habitat requirements, it is one of the world's rarest canids, Africa's most endangered carnivore. The species' current range is limited to seven isolated mountain ranges at altitudes of 3,000–4,500 m, with the overall adult population estimated at 360–440 individuals in 2011, more than half of them in the Bale Mountains; the Ethiopian wolf is listed as endangered by the IUCN, on account of its small numbers and fragmented range. Threats include increasing pressure from expanding human populations, resulting in habitat degradation through overgrazing, disease transference and interbreeding from free-ranging dogs, its conservation is headed by Oxford University's Ethiopian Wolf Conservation Programme, which seeks to protect wolves through vaccination and community outreach programs.
Alternative English names for the Ethiopian wolf include Abyssinian wolf, Simien fox, Simien jackal, Ethiopian jackal, red fox, red jackal, Abyssinian dog and cuberow. The earliest written reference to the species comes from Solinus's Collectanea rerum memorabilium from the third century AD: The species was first scientifically described in 1835 by Eduard Rüppell, who provided a skull for the British Museum. European writers traveling in Ethiopia during the mid-19th century wrote that the animal's skin was never worn by natives, as it was popularly believed that the wearer would die should any wolf hairs enter an open wound, while Charles Darwin hypothesised that the species gave rise to greyhounds. Since it was scarcely heard of in Europe up until the early 20th century, when several skins were shipped to England by Major Percy Horace Gordon Powell-Cotton during his travels in Abyssinia; the Ethiopian wolf was recognised as requiring protection in 1938, received it in 1974. The first in-depth studies on the species occurred in the 1980s with the onset of the American-sponsored Bale Mountains Research Project.
Ethiopian wolf populations in the Bale Mountains National Park were negatively affected by the political unrest of the Ethiopian Civil War, though the critical state of the species was revealed during the early 1990s after a combination of shooting and a severe rabies epidemic decimated most packs studied in the Web Valley and Sanetti Plateau. In response, the IUCN reclassified the species from endangered to critically endangered in 1994; the IUCN/SSC Canid Specialist Group advocated a three-front strategy of education, wolf population monitoring, rabies control in domestic dogs. The establishment of the Ethiopian Wolf Conservation Programme in Bale soon followed in 1995 by Oxford University, in conjunction with the Ethiopian Wildlife Conservation Authority. Soon after, a further wolf population was discovered in the Central Highlands. Elsewhere, information on Ethiopian wolves remained scarce. Wolves were recorded in the Arsi Mountains since the early 20th century, in the Bale Mountains in the late 1950s.
The status of the Ethiopian wolf was reassessed in the late 1990s, following improvements in travel conditions into northern Ethiopia. The surveys taken revealed local extinctions in Mount Choqa, in every northern Afroalpine region where agriculture is well developed and human pressure acute; this revelation stressed the importance of the Bale Mountains wolf populations for the species' long-term survival, as well as the need to protect other surviving populations. A decade after the rabies outbreak, the Bale populations had recovered to pre-epizootic levels, prompting the species' downlisting to endangered in 2004, though it still remains the world's rarest canid, Africa's most endangered carnivore. Although fossil records exist of wolf-like canids from Late Pleistocene Eurasia, no fossil records are known for the Ethiopian wolf. In 1994, a mitochondrial DNA analysis showed a closer relationship to the gray wolf and the coyote than to other African canids, C. simensis may be an evolutionary relic of a gray wolf-like ancestor's past invasion of northern Africa from Eurasia.
See further: Canis evolutionDue to the high density of rodents in their new Afroalpine habitat, the ancestors of the Ethiopian wolf developed into specialised rodent hunters. This specialisation is reflected in the animal's skull morphology, with its elongated head, long jaw, spaced teeth. During this period, the species attained its highest abundance, had a continuous distribution; this changed about 15,000 years ago with the onset of the current interglacial, which caused the species' Afroalpine habitat to fragment, thus isolating Ethiopian wolf populations from each other. The Ethiopian wolf is one of five Canis species present in Africa, is distinguishable from jackals by its larger size longer legs, distinct reddish coat, white markings. John Edward Gray and Glover Morrill Allen classified the species under a separate genus and Oscar Neumann considered it to be "only an exaggerated fox". Juliet Clutton-Brock refuted the separate genus in favour of placing the species in the genus Canis, upon noting cranial similarities with the side-striped jackal.
In 2015, a study of mitochondrial genome sequences and whole genome nuclear sequences of African and Eurasian canids