Hyrax
From Wikipedia, the free encyclopedia
| Hyraxes Fossil range: Early Eocene–Recent |
||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 |
||||||||||||||
| Scientific classification | ||||||||||||||
|
||||||||||||||
| Genera | ||||||||||||||
A hyrax (from Greek ὑραξ 'shrewmouse') is any of four species of fairly small, thickset, herbivorous mammals in the order Hyracoidea. They live in Africa and the Middle East.
Hyraxes are well-furred rotund creatures with a mere stump for a tail. They are about one-third the size of a Corgi; most measure between 30-70 cm long and weigh between 2-5kg. From a distance, a hyrax could be mistaken for a very well-fed rabbit or guinea pig.
Contents |
[edit] Characteristics
Hyraxes retain a number of early mammalian characteristics; in particular they have poorly developed internal temperature regulation (which they deal with by huddling together for warmth, and by basking in the sun like reptiles). Unlike other browsing and grazing animals, they do not use the incisors at the front of the jaw for slicing off leaves and grass, and use the molar teeth at the side of the jaw instead. The incisors are nonetheless large, and grow continuously through life, in a similar manner to those of rodents. There is a short diastema between the incisors and the cheek teeth. The dental formula for hyraxes is:
| Dentition |
|---|
| 1.0.4.3 |
| 2.0.4.3 |
Unlike the even-toed ungulates and some of the macropods, hyraxes do not chew cud to help extract nutrients from coarse, low-grade leaves and grasses. They do, however, have complex, multi-chambered stomachs which allow symbiotic bacteria to break down tough plant materials, and their overall ability to digest fibre is similar to that of the ungulates.
Hyraxes inhabit rocky terrain across sub-Saharan Africa. Their feet have rubbery pads with numerous sweat glands, which help the animal maintain its grip when moving fast up steep rocky surfaces. They also have efficient kidneys, retaining water so that they can survive in arid environments.
Female hyraxes give birth to up to four young after a gestation period of between seven and eight months, depending on the species. The young are weaned at one to five months of age, and reach sexual maturity at sixteen to seventeen months. Male hyraxes have testicles that do not reside in the scrotum, much like elephants, manatees and dugongs.
Hyraxes live in small family groups, dominated by a single male who aggressively defends the territory from rivals. Where there is abundant living space, the male may dominate multiple groups of females, each with their own range. The remaining males live solitary lives, often on the periphery of areas controlled by larger males, and mate only with younger females[1] .
[edit] Historical accounts
Early Phoenician navigators mistook the rabbits of the Iberian Peninsula for hyraxes (phoenician Shapan); hence they named it I-Shapan-im, meaning "land of the hyraxes", which possibly became the Latin word "Hispania", the root of Spain's modern Spanish name España and the English name Spain.[citation needed]
The word "rabbit, or "hare" was used instead of "hyrax" many times in some earlier English Bible translations. European translators of those times had no knowledge of the hyrax (Hebrew שָּׁפָן Shaphan[2]), and therefore no name for them. There are references to hyraxes in the Old Testament[3] particularly in Leviticus 11, where they are named as unclean animals and are thus not kosher, although even some of the the modern translations refer to them as rock badgers.
[edit] Evolution
Hyraxes are sometimes described as being the closest living relative to the elephant.[4] This is because they may share an ancestor in the distant past when hyraxes were larger and more diverse. However, the details of their taxonomic relationship remain to be fully verified.
All modern hyraxes are members of the family Procaviidae (the only living family within the Hyracoidea) and are found only in Africa and the Middle East. In the past, however, hyraxes were more diverse and widespread. The order first appears in the fossil record over 40 million years ago, and for many millions of years hyraxes were the primary terrestrial herbivore in Africa, just as odd-toed ungulates were in the Americas. There were many different species, the largest of them about the weight of a small horse, the smallest the size of a mouse. During the Miocene, however, competition from the newly-developed bovids—very efficient grazers and browsers—pushed the hyraxes out of the prime territory and into marginal niches. Nevertheless, the order remained widespread, diverse and successful as late as the end of the Pliocene (about two million years ago) with representatives throughout most of Africa, Europe and Asia.
The descendants of the giant hyracoids evolved in different ways. Some became smaller, and gave rise to the modern hyrax family. Others appear to have taken to the water (perhaps like the modern capybara), and ultimately gave rise to the elephant family, and perhaps also the Sirenians (dugongs and manatees). DNA evidence supports this hypothesis, and the small modern hyraxes share numerous features with elephants, such as toenails, excellent hearing, sensitive pads on their feet, small tusks, good memory, high brain functions compared to other similar mammals, and the shape of some of their bones.[5]
Not all scientists support the proposal that hyraxes are the closest living relative of the elephant. Recent morphological and molecular based classifications reveal the Sirenians to be the closest living relatives of elephants, while hyraxes are closely related but form an outgroup to the assemblage of elephants, sirenians, and extinct orders like Embrithopoda and Desmostylia.[6].
[edit] List of extinct species
[edit] Living species
Scientists have recently reduced the number of distinct species of hyrax recognized. As recently as 1995 there were eleven or more recognized species; only four are recognized today. The remaining species are regarded as subspecies of the remaining four. There are over 50 recognized subspecies and species, many of which are considered highly endangered.[7]
- ORDER HYRACOIDEA
- Family Procaviidae
- Genus Dendrohyrax
- Southern Tree Hyrax, Dendrohyrax arboreus
- Western Tree Hyrax, Dendrohyrax dorsalis
- Genus Heterohyrax
- Yellow-spotted Rock Hyrax, Heterohyrax brucei
- Genus Procavia
- Rock Hyrax, Procavia capensis
- Genus Dendrohyrax
- Family Procaviidae
[edit] References
 |
This article needs additional citations for verification. Please help improve this article by adding reliable references (ideally, using inline citations). Unsourced material may be challenged and removed. (July 2007) |
- ^ Hoeck, Hendrik (1984). Macdonald, D.. ed. The Encyclopedia of Mammals. New York: Facts on File. pp. 462–465. ISBN 0-87196-871-1.
- ^ "Shaphan" in Strong's Concordance
- ^ Lev 11:4-8; Deut 14:7; Ps 104:18; Prov 30:26
- ^ "Hirax Song is a Menu for Mating". 15 January 2009. http://www.economist.com/science/displaystory.cfm?story_id=12926018. Retrieved on 15 January 2009.
- ^ "Hyrax: The Little Brother of the Elephant", Wildlife on One, BBC TV.
- ^ Asher, R.J., Novacek, M.J., Geisher, J.H. (2003). "Relationships of endemic African mammals and their fossil relatives based on morphological and molecular evidence". J. Mamm. Evol. 10: 131–194. doi:.
- ^ Shoshani, Jeheskel (November 16, 2005). Wilson, D. E., and Reeder, D. M. (eds). ed. Mammal Species of the World (3rd edition ed.). Johns Hopkins University Press. pp. 87-89. ISBN 0-801-88221-4. http://www.bucknell.edu/msw3.
[edit] External links
 |
Look up hyrax in Wiktionary, the free dictionary. |
 |
Wikimedia Commons has media related to: Hyrax |
|
||||||||||||||
|
|||||||||||||||||||
