SUBORDER TYLOPODA: CAMELS
This suborder is intermediate between the Suina and
the Ruminantia.
All living tylopods are members of the family
Camelidae, but there were several interesting extinct
families:
- Cainotheriidae: a
family of rabbit and hare-like tylopods from Europe.
- Protoceratidae: a
family of horned tylopods, very like the horned pecorans in the
Suborder Ruminantia.
- Merycoidodontodae: a
family of sheep-sized tylopods, similar to large hyraxes. They
lived in large herds in the open habitats
of North America.
FAMILY CAMELIDAE
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XH19-8.2 Camel
(Camelus sp.)
skull.
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Originally, camels were found only in North America,
but they migrated elsewhere in the Pleistocene. Both modern members
of the genus Camelus occur in the Old World.
The dromedary (Camelus
dromedarius) is very widespread, due to its
domestication, although no wild population remains. The bactrian
( C. bactrianus) camel
is less widely used by man, and only a few wild herds remain in
central Asia. As long as the nomads of Asia and north Africa remain,
camels probably have a secure future.
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Dromedary
(Camelus
dromedarius) camels with their owners
in Ethiopia.
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The camel is renowned for its adaptations to desert
life:
- it rarely sweats and produces little urine and
dry fæces.
- 30 gallons can be drunk all in one go.
- the hump consists of fat deposits for energy
storage.
- the thick coat insulates against both temperature
extremes.
- it can tolerate a body temperature 8šC higher
than normal.
- nostril cavities in the skull moisten inhaled
air.
Members of the Camelidae have:
- less fusion of lower leg bones than
ruminants;
- canines still present (lower canines not
incisor-like);
- lost the upper incisors;
- a chambered stomach, but less complex than in
ruminants.
Furthermore, the camels showed a reduction in the
lateral toes far earlier than the ruminants, with the 2nd and 5th
toes now completely absent they display a very advanced foot
structure.
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XH19-6.1.
Llama glama
skull.
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 Llamas at Edinburgh Zoo
The llama, and the related alpaca, were both
domesticated around 4,500 years ago in South America. The llama is a
beast of burden; the alpaca provides wool. It is not known whether
they were ever wild. They may have been bred from wild species of
Llama: either the
mountain dwelling vicuna or the lowland guanaco. 50 million guanaco
were once found in Patagonia alone: today there are only 500,000.
None of these species have humps like the camels.
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Camels are used as beasts of burden
throughout North Africa, the Middle East and Central
Asia.
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