Hyrax

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Hyraxes
Fossil range: Early Eocene - Recent

Heterohyrax brucei

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Infraclass:	Eutheria
Superorder:	Paenungulata
Order:	Hyracoidea Huxley, 1869
Family:	Procaviidae Thomas, 1892

Genera

Procavia
Heterohyrax
Dendrohyrax

A hyrax (from Greek ὑραξ 'shrewmouse'; South African English: klipdassie) is any of four species of fairly small, thickset, herbivorous mammals in the order Hyracoidea. They live in Africa and the Middle East.

1 Characteristics
2 Historical accounts
3 Prehistoric hyraxes
4 Hyraxes today
5 Relation to elephants
6 Living species
7 References
8 External links

[edit] Characteristics

Hyraxes are well-furred rotund creatures with a mere stump for a tail. They are about the size of a domestic cat; most measure between 30 and about 70 cm long and weigh between 2 and 5 kg. From a distance and with a little imagination, a hyrax could be mistaken for a very well-fed rabbit or guinea pig.

[edit] Historical accounts

Early Phoenician navigators mistook the rabbits of the Iberian Peninsula for hyraxes (Hebrew Shaphan); hence they named it I-Shapan-im, meaning "land of the hyraxes", which became the Latin word "Hispania", the root of Spain's modern Spanish name España and the English name Spain.

The word "rabbit" 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^[1]), and therefore no name for them. There are references to hyraxes in the Old Testament^[2] which seem to mistakenly identify hyraxes and rabbits as ruminating animals. This is possibly because they "appear to be so from working the jaws on the grasses they live on."^[3]).

[edit] Prehistoric hyraxes

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 theory, 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. Early Hyraxes may also have given rise to the Glires clade (rodents and lagomorphs).^{[citation needed]}

[edit] Hyraxes today

Tree Hyrax in the Serengeti, Tanzania

Present-day hyraxes retain a number of early mammal 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 have well developed incisors at the front of the jaw for slicing off leaves and grass, and need to use the teeth at the side of the jaw instead. 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.

Scientists have recently reduced the number of distinct species of hyrax recognized. While as recently as 1995 there were eleven or more recognized species, there are only four recognized today. The remaining species are regarded as subspecies of the remaining four. In fact, there are over 50 recognized species and subspecies, though many are considered highly endangered.^[4]

[edit] Relation to elephants

Hyraxes are widely stated to be the closest living relatives of elephants. This is not so. Though both are within the cohort of mammals known as Afrotheria, the Hyrax is not the closest living relative of the elephant. Elephants (Proboscidea) and hyraxes (Hyracoidae) are both more closely related to manatees and dugongs (Sirenia) than they are to one another. (See: Kemp, T.S., 2005 The Origin and Evolution of Mammals, Oxford University Press, at 252-253; citing Asher et al., 2003, 'Relationships of endemic African mammals and their fossil relatives based on morphological and molecular evidence', Journal of Mammalian Evolution 10: 131 - 194").

[edit] Living species

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
    - Cape Hyrax, Procavia capensis

[edit] References

^ "Shaphan" in Strong's Concordance
^ Lev 11:4-8; Deut 14:7; Ps 104:18; Prov 30:26
^ Commentary on Lev. 11:5,6 by Robert Jamieson
^ Shoshani, Jeheskel (November 16, 2005). in Wilson, D. E., and Reeder, D. M. (eds): Mammal Species of the World, 3rd edition, Johns Hopkins University Press, 87-89. ISBN 0-801-88221-4.