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Striped hyena
Temporal range: Middle Pleistocene – Recent
Striped Hyena Adult.jpg
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Hyaenidae
Genus: Hyaena
Species: H. hyaena
Binomial name
Hyaena hyaena
(Linnaeus, 1758) [2]
Striped Hyaena area.png
Striped hyena range
Synonyms[3]
Canis hyaena Linnaeus, 1758
(numerous others)

The striped hyena (Hyaena hyaena) is a species of true hyena native to North and East Africa, the Middle East, the Caucasus, Central Asia and the Indian Subcontinent. It is listed by the IUCN as near threatened, as the global population is estimated to be under 10,000 mature individuals which continues to experience deliberate and incidental persecution along with a decrease in its prey base such that it may come close to meeting a continuing decline of 10% over the next three generations.[1]

It is the smallest of the genus Hyaena, and retains many basal viverrid characteristics lost in larger species,[4] having a smaller and less specialised skull.[5][6] Though primarily a scavenger, large specimens have been known to kill their own prey,[7] and attacks on humans have occurred on rare instances. The striped hyena is a monogamous animal, with both males and females assisting one another in raising their cubs. A nocturnal animal, the striped hyena typically only emerges in complete darkness, and is quick to return to its lair before sunrise.[6] Though it has a habit of feigning death when attacked, it has also been known to stand its ground against larger predators such as leopards in disputes over food.[8]


[9]

[10]

[11]

Physical description[edit]

Build[edit]

Dentition, as illustrated in Knight's Sketches in Natural History
Skeleton.

The striped hyena has a fairly massive, but short torso set on long legs. The hind legs are significantly shorter than the forelimbs, thus causing the back to slope downwards. The legs are relatively thin and weak, with the forelegs being bent at the carpal region. The neck is thick, long and largely immobile, while the head is heavy and massive with a shortened facial region. The eyes are small, while the sharply pointed ears are very large, broad and set high on the head. Like all hyenas, the striped hyena has bulky pads on its paws, as well as blunt but powerful claws. The tail is short and the terminal hairs do not descend below the calcaneal tendon. The striped hyena lacks the enlarged clitoris and false scrotal sack noted in the female genitalia of the spotted hyena.[6] The female has 3 pairs of teats.[8] Adult weight can range from 22 to 55 kg (49 to 121 lb), averaging at about 35 kg (77 lb). Body length can range from 85 to 130 cm (33 to 51 in), not counting a tail of 25 to 40 cm (9.8 to 15.7 in), and shoulder height is between 60–80 cm (24–31 in).[7] The male has a large pouch of naked skin located at the anal opening. Large anal glands open into it from above the anus. Several sebaceous glands are present between the openings of the anal glands and above them.[8] The anus can be everted up to a length of 5 cm, and is everted during social interaction and mating. When attacked, the striped hyena everts its rectum and sprays a pungent smelling liquid from its anal glands.[6] Its eyesight is acute, though its senses of smell and hearing are weak.[8]

The skull is entirely typical of the genus, having a very high sagittal crest, a shortened facial region and an inflated frontal bone. The skull of the striped hyena differs from that of the brown[6] and spotted hyena by its smaller size and slightly less massive build. It is nonetheless still powerfully structured and well adapted to anchoring exceptionally strong jaw muscles[5] which give it enough bite-force to splinter a camel's thigh bone.[8] Although the dentition is overall smaller than that of the spotted hyena, the upper molar of the striped hyena is far larger.[5]

Fur[edit]

The winter coat is unusually long and uniform for an animal its size, with a luxuriant mane of tough, long hairs along the back from the occiput to the base of the tail. The coat is generally coarse and bristly, though this varies according to season. In winter, the coat is fairly dense, soft, and has well-developed underfur. The guard hairs are 50–75 mm long on the flanks, 150–225 mm long on the mane and 150 mm on the tail. In summer, the coat is much shorter and coarser, and lacks underfur, though the mane remains large.[12]

In winter, the coat is usually of a dirty-brownish grey or dirty gray colour. The hairs of the mane are light grey or white at the base, and black or dark brown at the tips. The muzzle is dark, greyish brown, brownish-grey or black, while the top of the head and cheeks are more lightly coloured. The ears are almost black. A large black spot is present on the front of the neck, and is separated from the chin by a light zone. A dark field ascends from the flanks ascending to the rear of the cheeks. The inner and outer surface of the forelegs are covered with small dark spots and transverse stripes. The flanks have four indistinct dark vertical stripes and rows of diffused spots. The outer surface of the thighs has 3–4 distinct vertical or oblique dark bands which merge into transverse stripes in the lower portion of the legs. The tip of the tail is black with white underfur.[12]

Geographic variation[edit]

As of 2005,[3] no subspecies are recognised. The striped hyena is nonetheless a geographically varied animal. Hyenas in the Arabian peninsula have an accentuated blackish dorsal mane, with mid-dorsal hairs reaching 20 cm in length. The base colour of Arabian hyenas is grey to whitish grey, with dusky grey muzzles and buff yellow below the eyes. Hyenas in Israel have a dorsal crest which is mixed grey and black in colour, rather than being predominantly black.[13] The largest striped hyenas come from the Middle East, Asia minor, central Asia and the Indian subcontinent, while those of east Africa and the Arabian peninsula are smaller.[14][15]


References[edit]

  1. ^ a b Arumugam, R., Wagner, A. & Mills, G. (2008). Hyaena hyaena. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 22 March 2009. Database entry includes a brief justification of why this species is of near threatened
  2. ^ Linnæus, Carl (1758). Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I (in Latin) (10 ed.). Holmiæ (Stockholm): Laurentius Salvius. p. 40. Retrieved 23 November 2012. 
  3. ^ a b Wilson, D. E.; Reeder, D. M., eds. (2005). "Hyaena hyaena". Mammal Species of the World (3rd ed.). Johns Hopkins University Press. ISBN 978-0-8018-8221-0. OCLC 62265494. 
  4. ^ Cite error: The named reference k66 was invoked but never defined (see the help page).
  5. ^ a b c Rosevear, D. R. (1974). The carnivores of West Africa. London : Trustees of the British Museum (Natural History). pp. 344-53. ISBN 0-565-00723-8
  6. ^ a b c d e Heptner, V. G. & Sludskii, A. A. (1992). Mammals of the Soviet Union: Carnivora (hyaenas and cats), Volume 2. Smithsonian Institution Libraries and National Science Foundation. pp. 8-47
  7. ^ a b Mills, G. & Hofer, H. (1998). Hyaenas: status survey and conservation action plan. IUCN/SSC Hyena Specialist Group. ISBN 2-8317-0442-1.
  8. ^ a b c d e Pocock, R. I. (1941). Fauna of British India: Mammals Volume 2. Taylor and Francis. pp. 65-73
  9. ^ Osborn, D. J. & Helmy, I. (1980). The contemporary land mammals of Egypt (including Sinai). Field Museum of Natural History. pp. 423-32
  10. ^ Rohland, N, Pollack, J. L., Nagel, D., Beauval, C., Airvaux, J., Paabo, S. & Hofreiter, M. (2005). The population history of extant and extinct hyenas. Mol. Biol. Evol,. 22: 2435–2443.
  11. ^ Rieger, I. (1981). Hyaena hyaena. Mammalian Species. No. 150, pp.1–5, 3 figs. American Society of Mammalogists
  12. ^ Cite error: The named reference h11 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference m21 was invoked but never defined (see the help page).
  14. ^ Mills & Hofer 1998, p. 22
  15. ^ Osborn & Helmy 1980, p. 427