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*''C. a. algirensis''
*''C. a. algirensis''
*''C. a. bea''
*''C. a. bea''
*''[[Egyptian jackal|C. a. lupaster]]''
*''C. a. riparius''
*''C. a. riparius''
*''[[Variegated wolf|C. a. soudanicus]]''
*''[[Variegated wolf|C. a. soudanicus]]''
Line 118: Line 117:
|[[Kenya]], Northern [[Tanzania]]
|[[Kenya]], Northern [[Tanzania]]
|
|
|-
|'''Egyptian wolf'''<br/>''[[Egyptian wolf|Canis a. lupaster]]''
[[File:Lupaster.png|150 px]]
|[[Wilhelm Friedrich Hemprich|Hemprich]] and [[Christian Gottfried Ehrenberg|Ehrenberg]], 1833
| A large subspecies presenting a very grey wolf-like [[phenotype]].<ref name="gaubert"/>
|[[Egypt]], [[Algeria]], [[Mali]], [[Ethiopian Highlands]], and [[Senegal]]
|''C. aureus lupaster''<br>
''C. lupaster''<br>
''C. lupus lupaster''<br>
''C. sacer'' (Hemprich and Ehrenberg, 1833)
|-
|'''Somali wolf'''<br/>''Canis a. riparius''
|'''Somali wolf'''<br/>''Canis a. riparius''
|[[Wilhelm Friedrich Hemprich|Hemprich and Ehrenberg]], 1832
|[[Wilhelm Friedrich Hemprich|Hemprich and Ehrenberg]], 1832

Revision as of 11:45, 11 August 2015

African golden wolf
Temporal range: 1-1.7–0 Ma
↓
Early Pleistocene – Recent
Canis anthus bea in Ngorongoro Crater, Tanzania
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Carnivora
Family:
Canidae
Genus:
Canis
Species:
C. anthus
Binomial name
Canis anthus[1]
F. Cuvier, 1820
Subspecies

The African golden wolf (Canis anthus), also known as the African wolf or thoa, is a canid native to north and northeastern Africa. The species is common in North west and north-east Africa, occurring from Senegal to Egypt in the east, in a range including Morocco, Algeria, and Libya in the north to Nigeria, Chad and Tanzania in the south.[2] It is a desert-adapted canid, and is common in plains and steppe areas, including ones lacking abundant water. It is primarily a predator, targeting invertebrates and mammals as large as gazelle fawns, though larger animals are sometimes taken. Other foodstuffs include animal carcasses, human refuse, and fruit. The African wolf is a monogamous and territorial animal, whose social structure includes yearling offspring remaining with the family to assist in raising their parents' younger pups.[3]

It was previously classified as an African variant of the Eurasian golden jackal, with at least one subspecies (Canis anthus lupaster) having been classified as a grey wolf. In 2015, a series of analyses on the species' mtDNA and nuclear genome demonstrated that it was in fact distinct from the golden jackal, and more closely related to grey wolves and coyotes. It is nonetheless still close enough to the golden jackal to produce hybrid offspring, as indicated through genetic tests on jackals in Israel[4] and a 19th century captive crossbreeding experiment.[5] As the IUCN's golden jackal page has not been updated since 2008, it has yet to recognise the distinctiveness of the African wolf and give it its own conservation status, with population estimates being completely lacking.[6]

Physical description

Various C. anthus phenotypes, ranging from gracile jackal-like morphs to more robust wolf-like ones.

The African wolf is a small canid, with both sexes weighing between 7–15 kg (15.6–33 lbs), and standing 40 cm in height. It has a relatively long snout and ears, while the tail is comparatively short, measuring 20 cm in length. Fur colour varies individually, seasonally and geographically, though the typical colouration is yellowish to silvery grey, with slightly reddish limbs and black speckling on the tail and shoulders. The throat, abdomen and facial markings are usually white, and the eyes are amber coloured. Females bear 4–8 teats.[3] Although superficially similar to the Eurasian golden jackal (particularly in East Africa), the African golden wolf has a more pointed muzzle and sharper, more robust teeth.[4] The ears are longer in the golden wolf, and the skull has a more elevated forehead.[7]

Taxonomic history

Skull of African wolf (left) and golden jackal (right).

Aristotle wrote of wolves living in Egypt, mentioning that they were smaller than the Greek kind. Georg Ebers wrote of the wolf being among the sacred animals of Egypt, describing it as a "smaller variety" of wolf to those of Europe, and noting how the name Lykopolis, the Ancient Egyptian city dedicated to Anubis, means "city of the wolf".[8][9]

The African golden wolf was first recognised as being a separate species from the Eurasian golden jackal by Frédéric Cuvier in 1820, who described it as being a more elegant animal, with a more melodic voice and a less strong odour. The binomial name he chose for it was derived from the Arcadian Anthus family described by Pliny the Elder in his Natural History, whose members would draw lots to become werewolves.[1] Eduard Rüppell proposed that the animal was the ancestor of Egyptian sighthounds, and named it Wolf's-hund (wolf dog),[10] while Charles Hamilton Smith named it "thoa" or "thous dog".[11] An attempt was also made in 1821 to hybridise the two species in captivity, resulting in the birth of five pups, three of which died before weaning. The two survivors were noted to never play with each other and had completely contrasting temperaments; one inherited the golden jackal's shyness, while the other was affectionate toward its human captors.[5] English biologist St. George Jackson Mivart emphasised the differences between the African wolf and the golden jackal in his writings:

Illustration of golden jackal-African wolf hybrids bred in captivity (1821).

... it is a nice question whether the Common Jackal of North Africa should or should not be regarded as of the same species [as the golden jackal]... Certainly the differences of coloration which exist between these forms is not nearly so great as those which are to be found to occur between the different local varieties of C. lupus. We are nevertheless inclined... to keep the North-African and Indian Jackals distinct... The reasons why we prefer to keep them provisionally distinct is that though the difference between the two forms (African and Indian) is slight as regards coloration, yet it appears to be a very constant one. Out of seventeen skins of the Indian form, we have only found one which is wanting in the main characteristic as to difference of hue. The ears also are relatively shorter than in the North-African form. But there is another character to which we attach greater weight. However much the different races of Wolves differ in size, we have not succeeded in finding any constant distinctive characters in the form of the skull or the proportions of the lobes of any of the teeth. So far as we have been able to observe, such differences do exist between the Indian and North-African Jackals.

— Mivart (1890)[12]
Comparative illustration of C. aureus (top) and C. anthus (bottom).

Although subsequently synonymised with the golden jackal, new doubts over its being conspecific with the golden jackal arose in 2011, when several golden "jackal" populations in Egypt and the Horn of Africa classed as Canis aureus lupaster were found to have mtDNA sequences more closely resembling those in grey wolves than those of golden jackals.[8] These wolf-like mtDNA sequences were confirmed to occur over a range 6,000 km wide, encompassing Algeria, Mali and Senegal. In both these studies, it was proposed to reclassify Canis aureus lupaster as a subspecies of grey wolf.[13]

In 2015 however, a more thorough comparative study of mitochondrial and nuclear genomes on both Eurasian golden jackals and their African counterparts revealed that the latter were in fact a separate species more closely related to grey wolves and coyotes, with a genetic divergence of around 6.7%,[4] which is greater than that between grey wolves and coyotes (4%) and that between grey wolves and domestic dogs (0.2%).[14] The phylogenetic tree below is based on nuclear sequences:[4]

African golden wolf (formerly African golden jackal), Canis anthus[4]: Fig. 2 

Ethiopian wolf

Eurasian golden jackal, Canis aureus[4]: Fig. 2 

Dhole

It was estimated that the African golden wolf diverged from the wolf-coyote clade 1-1.7 million years ago during the Pleistocene, and that its superficial similarity to the Eurasian golden jackal (particularly in East Africa, where African wolves are similar in size to golden jackals) is a case of parallel evolution. Considering its phylogenetic position and the canid fossil record, it is likely that the African wolf evolved from larger-sized ancestors which became progressively more jackal-like in size upon populating Africa on account of interspecific competition with both larger and smaller-sized indigenous carnivores. Because of Egypt's contiguity with Israel, traces of golden wolf DNA were identified in Israeli golden jackals, thus indicating the presence of a hybrid zone.[4]

Subspecies

As of 2015, MSW3 still classifies the six African wolf subspecies as part of Canis aureus.[15]

Although in the past several attempts have been made to synonymise many of the proposed names, the taxonomic position of West African wolves, in particular, is too confused to come to any precise conclusion, as the collected study materials are few. Prior to 1840, six of the ten supposed West African subspecies were named or classed almost entirely because of their fur colour.[16]

The species' display of high individual variation, coupled with the scarcity of samples and the lack of physical barriers on the continent preventing gene flow, brings into question the validity of some of the West African forms.[16]

Behaviour

Social and reproductive behaviours

The African wolf's social organisation is extremely flexible, varying according to the availability and distribution of food. The basic social unit is a breeding pair, followed by its current offspring, or offspring from previous litters staying as "helpers".[19] Large groups are rare, and have only been recorded to occur in areas with abundant human waste. Family relationships among golden wolves are comparatively peaceful compared to those of the black-backed jackal; although the sexual and territorial behaviour of grown pups is suppressed by the breeding pair, they are not actively driven off once they attain adulthood. Golden wolves also lie together and groom each other much more frequently than black-backed jackals. In the Serengeti, pairs defend permanent territories encompassing 2–4 km², and will vacate their territories only to drink or when lured by a large carcass.[20] The pair patrols and marks its territory in tandem. Both partners and helpers will react aggressively towards intruders, though the greatest aggression is reserved for intruders of the same sex; pair members do not assist each other in repelling intruders of the opposite sex.[21]

Threat posture of C. a. lupaster (left) and C. a. anthus (right)

The African wolf's courtship rituals are remarkably long, during which the breeding pair remains almost constantly together. Prior to mating, the pair patrols and scent marks its territory. Copulation is preceded by the female holding her tail out and angled in such a way that her genitalia are exposed. The two approach each other, whimpering, lifting their tails and bristling their fur, displaying varying intensities of offensive and defensive behaviour. The female sniffs and licks the male's genitals, whilst the male nuzzles the female's fur. They may circle each other and fight briefly. The copulatory tie lasts roughly four minutes. Towards the end of estrus, the pair drifts apart, with the female often approaching the male in a comparatively more submissive manner. In anticipation of the role he will take in raising pups, the male regurgitates or surrenders any food he has to the female. In the Serengeti, pups are born in December–January, and begin eating solid food after a month. Weaning starts at the age of two months, and ends at four months. At this stage, the pups are semi-independent, venturing up to 50 metres from the den, even sleeping in the open. Their playing behaviour becomes increasingly more aggressive, with the pups competing for rank, which is established after six months. The female feeds the pups more frequently than the male or helpers do, though the presence of the latter allows the breeding pair to leave the den and hunt without leaving the litter unprotected.[22]

The African wolf's life centres around a home burrow, which usually consists of an abandoned and modified aardvark or warthog earth. The interior structure of this burrow is poorly understood, though it is thought to consist of a single central chamber with 2–3 escape routes. The home burrow can be located in both secluded areas or surprisingly near the dens of other predators.[23]

Serengeti wolf (C. a. bea) eating an agama

Communication

African wolves frequently groom one another, particularly during courtship, during which it can last up to ½ hour. Nibbling of the face and neck is observed during greeting ceremonies. When fighting, the African wolf slams its opponents with its hips, and bites and shakes the shoulder. The species' postures are typically canine, and it has more facial mobility than the black-backed and side-striped jackals, being able to expose its canine teeth like a dog.[24]

The vocabulary of the African wolf is similar to that of the domestic dog, with seven sounds having been recorded.[25] The African wolf's vocalisations include howls, barks, growls, whines and cackles.[24] Subspecies can be recognised by differences in their howls.[25] One of the most commonly heard sounds is a high, keening wail, of which there are three varieties; a long single toned continuous howl, a wail that rises and falls, and a series of short, staccato howls. These howls are used to repel intruders and attract family members. Howling in chorus is thought to reinforce family bonds, as well as establish territorial status.[24]

Hunting behaviour

The African wolf rarely catches hares due to them being faster. Gazelle mothers (often working in groups of two or three) are formidable when defending their young against single wolves, which are much more successful in hunting gazelle fawns when working in pairs. A pair of wolves will methodically search for concealed gazelle fawns within herds, tall grass, bushes and other likely hiding places.[26]

Although it is known to kill animals up to three times its own weight, the golden wolf targets mammalian prey much less frequently than the black-backed jackal overall.[26] On capturing large prey, the African wolf makes no attempt to kill it; instead it rips open the belly and eats the entrails. Small prey is typically killed by shaking, though snakes may be eaten alive from the tail end. The African wolf often carries away more food than it can consume, and caches the surplus, which is generally recovered within 24 hours.[23] When foraging for insects, the African wolf turns over dung piles to find dung beetles. During the dry seasons, it excavates dung balls to reach the larvae inside. Grasshoppers and flying termites are caught either by pouncing on them while they are on the ground or are caught in mid-air. It is fiercely intolerant of other scavengers, having been known to dominate vultures on kills – one can hold dozens of vultures at bay by threatening, snapping and lunging at them.[26]

Ecology

Diet

A Serengeti wolf (C. a. bea) carefully navigating a herd of blue wildebeest in the Ngorongoro National Park, Tanzania

In West Africa, the African wolf mostly confines itself to small prey, such as hares, rats, ground squirrels and grass cutters. Other prey items include lizards, snakes, and ground-nesting birds, such as francolins and bustards. It also consumes a large amount of insects, including dung beetles, larvae, termites and grasshoppers. It will also kill young gazelles, duikers and warthogs.[23] In East Africa, it consumes invertebrates and fruit, though 60% of its diet consists of rodents, lizards, snakes, birds, hares and Thomson's gazelles.[19] During the wildebeest calving season, African wolves will feed almost exclusively on their afterbirth.[27] In the Serengeti and Ngorongoro Crater, less than 20% of its diet comes from scavenging.[26]

Enemies and competitors

The African wolf tends to dominate smaller canid species, and has been observed to kill the pups of black-backed jackals.[19] It often eats alongside African wild dogs, and will stand its ground if the dogs try to harass it.[26] There is at least one record of an African wolf pack adopting a male Ethiopian wolf.[28]

Wolves will feed alongside spotted hyenas, though they will be chased if they approach too closely. Spotted hyenas will sometimes follow wolves during the gazelle fawning season, as wolves are effective at tracking and catching young animals. Hyenas do not take to eating wolf flesh readily; four hyenas were reported to take half an hour in eating one. Overall, the two animals typically ignore each other when no food or young is at stake.[29] Wolves will confront a hyena approaching too closely to their dens by taking turns in biting the hyena's hocks until it retreats.[26]

Wolves in the Serengeti are known to carry the canine parvovirus, canine herpesvirus, canine coronavirus and canine adenovirus.[19]

In folklore

In Egyptian folklore, the wolf can cause chickens to faint from fear by simply passing underneath their roosts, and its body parts are associated with various forms of folk magic; placing a wolf's tongue into a house is believed to cause the inhabitants within to argue, and its meat thought to be useful in treating insanity and epilepsy. Its heart is believed to protect the bearer from wild animal attacks, while its eye can protect against the evil eye.[30]

See also

Wikimedia Commons has media related to African golden wolf (Canis anthus).

References

  1. ^ a b Template:Fr icon Cuvier, Frédéric (1824), Histoire naturelle des mammifères, tome 2, A Paris : Chez A. Belin ...
  2. ^ Template:IUCN2008
  3. ^ a b Estes, Richard (1992). "The behavior guide to African mammals: including hoofed mammals, carnivores, primates". University of California Press. pp. 398–399. ISBN 0-520-08085-8.
  4. ^ a b c d e f g Koepfli, K.-P.; Pollinger, J.; Godinho, R.; Robinson, J.; Lea, A.; Hendricks, S.; Schweizer, R. M.; Thalmann, O.; Silva, P.; Fan, Z.; Yurchenko, A. A.; Dobrynin, P.; Makunin, A.; Cahill, J. A.; Shapiro, B.; Álvares, F.; Brito, J. C.; Geffen, E.; Leonard, J. A.; Helgen, K. M.; Johnson, W. E.; O’Brien, S. J.; Van Valkenburgh, B.; Wayne, R. K. (2015-08-17). "Genome-wide Evidence Reveals that African and Eurasian Golden Jackals Are Distinct Species". Current Biology. 25. doi:10.1016/j.cub.2015.06.060.
  5. ^ a b Template:Fr icon Cuvier, Frédéric (1824), [1], tome 3, A Paris : Chez A. Belin ...
  6. ^ Golden jackal: A new wolf species hiding in plain sight, The Guardian, (30 July, 2015)
  7. ^ Mivart, George (1890), Dogs, Jackals, Wolves and Foxes: A Monograph of the Canidæ, R.H. Porter, London, pp. 41–43
  8. ^ a b Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1371/journal.pone.0016385, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with |doi=10.1371/journal.pone.0016385 instead.
  9. ^ Ferguson, W.W. (1981). "The systematic of Canis aureus lupaster (Carnivora : Canidae) and the occurrence of Canis lupus in North Africa, Egypt and Sinai". Mammalia. 4: 459–465.
  10. ^ Template:De icon Rüppell, Eduard (1826), Atlas zu der Reise im nördlichen Afrika, Frankfurt am Main : Gedruckt und in Commission bei Heinr. Ludw. Brönner, pp. 44–46
  11. ^ Smith, Charles Hamilton; Jardine, Sir William (1839). The natural history of dogs : canidae or genus canis of authors ; including also the genera hyaena and proteles, Volume I. Edinburgh : W. H. Lizars. pp. 193–194
  12. ^ Mivart, George (1890), Dogs, Jackals, Wolves and Foxes: A Monograph of the Canidæ, R.H. Porter, London, pp. 36–37
  13. ^ Gaubert P, Bloch C, Benyacoub S, Abdelhamid A, Pagani P; et al. (2012). "Reviving the African Wolf Canis lupus lupaster in North and West Africa: A Mitochondrial Lineage Ranging More than 6,000 km Wide". PLoS ONE. 7 (8): e42740. doi:10.1371/journal.pone.0042740. PMC 3416759. PMID 22900047. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link) CS1 maint: unflagged free DOI (link)
  14. ^ Wayne, Robert K. (1993). "Molecular evolution of the dog family". Trends in Genetics. 9 (6): 218–224. doi:10.1016/0168-9525(93)90122-X. PMID 8337763.
  15. ^ Wozencraft, W. C. (2005). "Order Carnivora". In Wilson, D. E.; Reeder, D. M. (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. pp. 532–628. ISBN 978-0-8018-8221-0. OCLC 62265494.
  16. ^ a b Rosevear, Donovan Reginald (1974). "The carnivores of West Africa". London : Trustees of the British Museum (Natural History). pp. 38–44. ISBN 1-175-10030-7.
  17. ^ Lydekker, Richard (1908). "The Game Animals of Africa". London, R. Ward, limited. p. 218
  18. ^ a b Lydekker, Richard (1908). "The Game Animals of Africa". London, R. Ward, limited. p. 460.
  19. ^ a b c d Jhala, Y. V. & Moehlman, P. D. 2004. Golden jackal Canis aureus
  20. ^ Estes, Richard (1992). "The behavior guide to African mammals: including hoofed mammals, carnivores, primates". University of California Press. pp. 399–400. ISBN 0-520-08085-8.
  21. ^ Estes, Richard (1992). "The behavior guide to African mammals: including hoofed mammals, carnivores, primates". University of California Press. p. 402. ISBN 0-520-08085-8.
  22. ^ Estes, Richard (1992). "The behavior guide to African mammals: including hoofed mammals, carnivores, primates". University of California Press. pp. 402–403. ISBN 0-520-08085-8.
  23. ^ a b c Rosevear, Donovan Reginald (1974). "The carnivores of West Africa". London : Trustees of the British Museum (Natural History). pp. 46–47. ISBN 1-175-10030-7.
  24. ^ a b c Estes, Richard (1992). "The behavior guide to African mammals: including hoofed mammals, carnivores, primates". University of California Press. pp. 401–402. ISBN 0-520-08085-8.
  25. ^ a b Kingdon, Jonathan (1988). "East African mammals: an atlas of evolution in Africa, Volume 3, Part 1". University of Chicago Press. pp. 22. ISBN 0-226-43721-3.
  26. ^ a b c d e f Estes, Richard (1992). "The behavior guide to African mammals: including hoofed mammals, carnivores, primates". University of California Press. pp. 400–401. ISBN 0-520-08085-8.
  27. ^ Kingdon, Jonathan (1988). "East African mammals: an atlas of evolution in Africa, Volume 3, Part 1". University of Chicago Press. pp. 19–21. ISBN 0-226-43721-3.
  28. ^ Sillero-Zubiri, C., and D. Gottelli (1994). Canis simensis. Mammalian Species 385: 1–6.
  29. ^ Kruuk, Hans (1972). The Spotted Hyena: A Study of Predation and Social Behaviour. Chicago: University of Chicago Press. ISBN 0-226-45507-6.
  30. ^ Obsorn, Dale. J.; Helmy, Ibrahim (1980). "The contemporary land mammals of Egypt (including Sinai)". Field Museum of Natural History, p. 371

Further reading

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