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(Redirected from Hyracoidea)
A 'hyrax' (from Greek 'shrewmouse'; Afrikaans: 'klipdassie') 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 the size of a Corgi; most measure between about 30 and 70 cm long and weigh between 2 and 5 kg. From a distance, a hyrax could be mistaken for a very well-fed rabbit or guinea pig.
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.
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 "grace" 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 ''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]).
Hyraxes are sometimes described as the closest living relative of the elephant. This is because they may share an ancestor in the distant past when hyraxes were larger and more diverse. However, the details of their relationship remain open to debate.
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.[4]
Not all scientists support the contention that hyraxes are the closest living relative of the elephant. T.S. Kemp's ''The Origin and Evolution of Mammals'' states that "Elephants (Proboscidea) and hyraxes (Hyracoidae) are both more closely related to manatees and dugongs (Sirenia) than they are to one another." Others state that both 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.
★ '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''
1. "Shaphan" in ''Strong's Concordance''
2. Lev 11:4-8; Deut 14:7; Ps 104:18; Prov 30:26
3. Commentary on Lev. 11:5,6 by Robert Jamieson
4. "Hyrax: The Little Brother of the Elephant", ''Wildlife on One'', BBC TV.
★ A BBC Science and Nature article on Hyrax
★ A reference to Hyrax on a website about elephants (includes video of Procavia capensis- video link dead-many links broken)
A 'hyrax' (from Greek 'shrewmouse'; Afrikaans: 'klipdassie') 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 the size of a Corgi; most measure between about 30 and 70 cm long and weigh between 2 and 5 kg. From a distance, a hyrax could be mistaken for a very well-fed rabbit or guinea pig.
| Contents |
| Characteristics |
| Historical accounts |
| Prehistory and relationship to elephants |
| Living species |
| References |
| External links |
Characteristics
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.
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 "grace" 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 ''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]).
Prehistory and relationship to elephants
Hyraxes are sometimes described as the closest living relative of the elephant. This is because they may share an ancestor in the distant past when hyraxes were larger and more diverse. However, the details of their relationship remain open to debate.
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.[4]
Not all scientists support the contention that hyraxes are the closest living relative of the elephant. T.S. Kemp's ''The Origin and Evolution of Mammals'' states that "Elephants (Proboscidea) and hyraxes (Hyracoidae) are both more closely related to manatees and dugongs (Sirenia) than they are to one another." Others state that both 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.
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''
References
1. "Shaphan" in ''Strong's Concordance''
2. Lev 11:4-8; Deut 14:7; Ps 104:18; Prov 30:26
3. Commentary on Lev. 11:5,6 by Robert Jamieson
4. "Hyrax: The Little Brother of the Elephant", ''Wildlife on One'', BBC TV.
External links
★ A BBC Science and Nature article on Hyrax
★ A reference to Hyrax on a website about elephants (includes video of Procavia capensis- video link dead-many links broken)
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