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http://animaldiversity.ummz.umich.edu/chordata/mammalia/


Order Hyracoidea

Family Procaviidae

(hyraxes)

Hyraxes, also known as dassies or conies, are jack-rabbit sized animals with short tails and peculiar, 3-toed hind feet with almost hoof-like nails on two of the toes (the inner toe has a claw). The forefeet have 5
toes. The soles of their fore- and hindfeet, which are moistened by special sweat glands, are remarkably soft and elastic, which works to increase their friction against the substrate. They have specialized muscles
in the soles of the feet that help them to work almost like a suction cup. The feet of hyraxes are mesaxonic, meaning that the plane of symmetry of the foot goes through the third digit. In this they resemble
perissodactyls.

The skulls of hyraxes have a short rostrum, prominent postorbital processes that form a postorbital bar, small bullae, a large jugal that contributes to the glenoid fossa, and a broad plate-like angular region of the
mandible. Hyraxes have a single incisor on each side of the upper jaw (two on the lower), followed by a diastema -- an arrangement that looks very rodent-like. Like those of rodents, the incisors of hyraxes
grow continuously and have enamel only on the anterior surface, creating a self-sharpening, chisel-like cutting edge. The molars have strongly developed lophs, as is common in species with herbivorous diets.
The dental formula is 1/2, 0/0, 4/4, 3/3 = 34.

Hyracoids are usually grouped with elephants and sirenians as "subungulates," and they all may have all descended from a common stock

The diet of hyraxes consists mostly of leaves, bark and grasses, but they also eat some insects. Some species are arboreal, while others live on rock outcrops. All are quick and agile climbers. They are active
during daylight hours. Rock-dwelling species live in colonies; arboreal species tend to be solitary. All make a variety of whistles, chatters, and other sounds.

There is a single family of hyraxes, Procaviidae, and seven living species. Hyraxes are found in sub-Saharan Africa and Middle East.

Technical characters



Species included in the Animal Diversity Web: 

        Dendrohyrax dorsalis (Tree Hyrax) -t- 
        Heterohyrax brucei (Yellow Spotted Hyrax) -pt- 
        Procavia capensis (Cape Hyrax) -pta- 

Accounts marked with a p contain pictures, t contain narrative text (student authored), a contain anatomical still/QTVR images, and s contain digitized sound clips. 


Literature and references cited

Feldhamer, G. A., L. C. Drickamer, S. H. Vessey, and J. F. Merritt. 1999. Mammalogy. Adaptation, Diversity, and Ecology. WCB McGraw-Hill, Boston. xii+563pp.

Jones, C. 1984. Tubulidentates, proboscideans, and hyracoideans. Pp. 523-535 in Anderson, S. and J. K. Jones, Jr. (eds). Orders and Families of Recent Mammals of the World. John Wiley and Sons, N.Y.
xii+686 pp.

Vaughan, T. A. 1986. Mammalogy. Third Edition. Saunders College Publishing, Fort Worth. vii+576 pp.

Vaughan, T. A., J. M. Ryan, N. J. Czaplewski. 2000. Mammalogy. Fourth Edition. Saunders College Publishing, Philadelphia. vii+565pp.


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^ Geographic Range

                                       Ethiopian: The tree hyrax inhabits mainly forest areas forming a band across mid-Africa extending from the eastern to the western coast. 

                                       ^ Physical Characteristics

                                       Mass: 1 to 5 kg.

                                       This rodent-looking mammal has short ears and legs, thick, soft fur with gray-brown to black colorings. The hyrax has a distinct patch of lighter colored hair
                                       on its back which covers a scent gland and bristles when the animal is excited or mating. Typically the tree hyrax is about 1-2.5 feet in length, has a height at
                                       the shoulders of 10-12 inches. 

                                       ^ Natural History 


                                       ^ Food Habits

                                              Unlike the other species of hyrax, the tree hyrax is a nocturnal forager. It is mainly herbivorous, feeding on leaves, fruits, bark, twigs, and
                                              grasses as well as an occasional insect. 

                                       ^ Reproduction

                                              The tree hyrax has an unusually long gestation period for its size; ranging from 6.5 to 7.5 months. Sexual maturity is reached around 16
                                              months of age. Litter sizes of 1-2 are common, unlike the larger litters of other hyraxes. The young are born fully furred and rather large.
                                              By the age of one day they are competent climbers. There is little data on the mating systems of these animals due to their nocturnal
                                              lifestyle, however it is believed that within the small groups there is one dominant male and the rest of the males form bachelor herds. 

^ Behavior

       These mammals are nocturnal and usually live a solitary life. There are some exceptions where they live in small family groups. Vocalization is a very important method for transferring
       information in these animals. They are known for their very loud and piercing contact calls that are generally made after dark when the hyrax is leaving to forage. 

^ Habitat

       Tree hyraxes inhabit various regions ranging from wooded areas and savannas to coastal dunes and tropical rainforests. 

       Biomes: tropical rainforest, tropical deciduous forest, tropical scrub forest, tropical savanna & grasslands

^ Economic Importance for Humans 


^ Positive

       The soft furs of the eastern tree hyrax are sold for a high price value in many regions. 

^ Conservation

Status:

       IUCN: No special status 
       U.S. ESA: No special status 
       CITES: No special status 

The status of the tree hyrax is said to be rare. Although not endangered, they are thought to be threatened due to habitat destruction. 

^ Other Comments

Despite their rodent-like appearance the hyrax have been placed in their own group due to their unique characteristics. However, their closest relatives are believed to be Proboscidea (elephants). Both have
developed a pair of upper incisors that are used as defensive tusks. Secondly the hyrax had flat nails on their feet that resemble the hoofs of elephants. According to amino acid sampling, these two groups
are closely related as well. 

^ References

Gaylard, A and G Kerley. 1997. Diet of Tree Hyraxes Dendrohyrax arboreus (Hyracoidea:Procaviidae) In the Eastern cape, South Africa. Journal of Mammalogy :213-219. 

Mailoiy, G and R Eley. 1992. The Hyrax. Regal Press, Nairobi. 

Sentman, Everett. 1992. . Grolier Electronic Publishing, Inc., . 

Wildlife Fact File. 1997. Tree Hyrax card 139. , . 

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                                     ^ Geographic Range

                                     Ethiopian: The yellow-spotted hyrax occurs from South eastern Egypt to Central Angola and Northern South Africa. 

                                     ^ Physical Characteristics

                                     Yellow-spotten Hyrax have a coat of thick, short, coarse fur. They range from 305- 380 mm in length, and they have no external tail. They resemble a guinea
                                     pig in appearance, but they are very different from caviomorph rodents. The feet of the hyrax are specialized in ways that allow these animals to locomote easily
                                     on slick rocks. The soles of their feet are naked, and are kept moist by the secretions of specialized glands. In addition, the musculature of the foot contracts the
                                     foot into a cup like shape. The net result is a suctioncup-like effect. The hyrax can cling with remarkable power to the rocky substrates they inhabit. 

                                     ^ Natural History 


                                     ^ Food Habits

                                            The yellow-spotted hyrax is a generalist browser. It eats many different types of vegetation. In Zambia, a colony was reported in which
                                            individuals ate primarily the leaves of the bitter yam. This plant is typicaly used by the native in the area to make poison arrows. In Kenya,
                                            these animals have been reported to rely heavily on grasses during the wet season. 

                                     ^ Reproduction

                                            The yellow-spotted hyrax breeds at the end of the wet season (April - June). The gestation of seven and a half months produces 1-4 young.
                                            The precocious young are born in a fur lined nest, and are capable of following adults around within several hours of birth. 

^ Behavior

       Hyrax are colonial animals. They often engage is social play and may live in groups containing hundreds of animals. Hyrax have keen hearing and sharp eyesight. They are constantly alert
       and have a scream-like alarm vocalization. Hyrax are fierce fighters and will bite savagely at anything that attacks them. The attentiveness and aggressive nature of hyrax are warranted, as
       rock python, birds of prey, leopards, and small carnivores such as mongoose may attempt to prey upon them at any time. 

^ Habitat

       The yellow-spotted hyrax is found exclusively in rocky areas. Colonies occur on rocky kopjes, rocky hillsides, krantzes, and in piles of loose boulders. They are typically found in
       mountainous regions at elevations of about 3800 meters. 

       Biomes: tropical scrub forest, tropical savanna & grasslands, mountains

^ Economic Importance for Humans 


^ Positive

       Humans eat hyrax when other food animals are scarce. The meat is reported to be tough and chewy, however, so Hyrax are eaten only when necessary. 

^ References

Nowak, R.M. and J.L. Paradiso. 1983. Walker's Mammals of the World, Fourth Edition. John Hopkins University Press, Baltimore, London. 

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^ Geographic Range

                                     Ethiopian: Syria south through NE Africa through most of sub-Saharan Africa. Isolated mountains in Libya and Algeria. 

                                     ^ Physical Characteristics

                                     In external appearance, hyraxes superficially resemble rabbits with short ears and tail. In all other respects, hyraxes are completely different from rabbits and
                                     are more closely related to elephants and other perissodactyls. The skull has a single pair of long, strong, tusk-like incisors and molars that resemble
                                     rhinoceros' molars. The feet are plantigrade (fore) to semi-digitigrade (hind). The soles of the feet have soft, large pads that are kept moist with sweat-like
                                     secretions. Male hyraxes are slightly larger than females (4kg vs 3.6kg). Measurements: Total length: 475-585mm; Tail length: 11-24mm; Hindfoot:
                                     65-76mm; Ear 27-38mm. 

                                     ^ Natural History 


                                     ^ Food Habits

                                            Procavia capensis eats a wide variety of herbaceous plants, favoring giant lobelia and members of the genus Senecio. New shoots and fruits
                                            are the preferred diet, but grasses up to 75% of the diet during the dry season. 

                                     ^ Reproduction

                                            The breeding season in Kenya is probably August-November, but may extend into January. In Syria, breeding occurs from
                                            August-September and young are born mid-March through early May. Two to three young are born after a 6-7 month gestation period. The
                                            young are well-developed at birth with fully-opened eyes and complete pelage. Young can ingest solid food after 2 weeks and are weaned at
                                            10 weeks. Young are sexually mature after 16 months, reach adult size at 3 years, and typically live about 10 years. 

^ Behavior

       Hyraxes live in herds of up to 80 individuals. These herds are subdivided into smaller flocks consisting of a few families and headed by an adult male. Hyraxes spend most of their time
       resting in large huddles or basking alone. These behaviors probably serve to help regulate body temperature as hyraxes' body temperature fluctuates with ambient temperature (i.e. they are
       not strictly homeothermic). 

^ Habitat

       Cape hyraxes live in crevices and cavities in rock outcroppings. They do not burrow, but they will inhabit burrows of other animals including those of aardvarks and meerkats. 

       Biomes: temperate grassland, tropical scrub forest, tropical savanna & grasslands

^ Economic Importance for Humans 


^ Positive

       Cape hyraxes produce large, communal piles of dung and urine that eventually congeal into a sticky mass. This substance (hyraceum) has been used by humans as a medicine for treating
       epilepsy, convulsions, and "women's disorders." 

^ Negative

       In times of large populations, hyraxes can move out of their rocky habitat and into areas of human habitiation where they may become pests by living in culverts and stone walls. 

^ References

Olds, N. and J. Shoshani (1982) Procavia capensis. Mammalian Species 171: 1-7. American Society of Mammalogists.