Aardvark
| Aardvark | ||||||||||||||
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| Orycteropus afer |
The Aardvark (Orycteropus afer) is a medium-sized mammal native to Africa. The name comes from the Dutch for "earth pig", because early settlers from Europe thought it resembled a pig (although aardvarks are not closely related to pigs).
The Aardvark is the only surviving member of the family Orycteropodidae and of the order Tubulidentata. The Aardvark was originally placed in the same genus as the South American anteaters because of superficial similarities which, it is now known, are the result of convergent evolution, not common ancestry. (For the same reason, Aardvarks bear a striking first-glance resemblance to the marsupial bilbies and bandicoots of Australasia, which are not placental mammals at all.)
The oldest known Tubulidentata fossils have been found in Kenya and date to the early Miocene. It appears that the order evolved in Africa during the late Cretaceous as part of the superorder Afrotheria, and spread to Europe and southern Asia during the later Miocene and early Pliocene. Three genera of the family Orycteropodidae are known: Leptorycteropus, Myorycteropus, and Orycteropus, the surviving Aardvark.
The most distinctive characteristic of the Tubulidentata is (as the name implies) their teeth which, instead of having a pulp cavity, have lots of thin tubes of dentine, each containing pulp and held together by cementum. The teeth have no enamel coating and are worn away and regrow continuosly. Aardvarks are born with conventional incisors and canines at the front of the jaw, but these fall out and are not replaced. In adult Aardvarks, the only teeth are the molars at the back of the jaw.
The pollex or "thumb" is absent on the front feet - resulting in four toes - while the hind feet have five toes each. Each toe bears a large, robust nail which is somewhat flattened and shovel-like, and appears to be intermediate between a claw and a hoof.
Aardvarks are only vaguely pig-like; the body is stout with an arched back; the limbs are of moderate length and armed with strong, blunt, shovel-like nails, somewhere between a claw and a hoof in shape. The front feet have lost the pollex (or 'thumb') but the rear feet have all 5 toes. The ears are disproportionately long and the tail very thick at the base with a gradual taper. The greatly elongated head is set on a short thick neck, and at the end of the snout is a disk in which the nostrils open. The mouth is typical of species that feed on termites: small and tubular. Aardvarks have long, thin, protrusible tongues and elaborate structures supporting a keen sense of smell.
| Cape Aardvark |
Weight is typically between 40 and 65 kilos; length is usually between 1 and 1.3 metres. Aardvarks are a pale yellowish grey in colour, often stained reddish-brown by soil. The coat is thin and the animal's primary protection is its tough skin; Aardvarks have been known to sleep in a recently excavated ant nest, so well does it protect them.
In the past, several individual species of Aardvark were named, however current knowledge indicates that there is only one species, Orycteropus afer, with several subspecies; 18 have been listed but most are regarded by authorities as invalid.
Aardvarks are nocturnal and solitary creatures that feed almost exclusively on ants and termites. An Aardvark emerges from its burrow in the late afternoon or shortly after sunset, and forages over a considerable home range, swinging its long nose from side to side to pick up the scent of food. When a concentration of ants or termites is found, the Aardvark digs into it with its powerful front legs, keeping its long ears upright to listen for predators, and takes up an astonishing number of insects with its long, sticky tongue—as many as 50,000 in one night has been recorded. They are exceptionally fast diggers, but otherwise move rather slowly.
Aside from digging out ants and termites, Aardvarks also excavate burrows to live in: temporary sites scattered around the home range as refuges, and the main burrow which is used for breeding. Main burrows can be deep and extensive, have several entrances, and be 13 metres long. Aaardvarks change the layout of their home burrow regularly, and from time to time move on and make a new one.
A single young weighing around 2 kg is born, and is able to leave the burrow to accompany its mother after only two weeks. At six months of age it is digging its own burrows, but it will often remain with the mother until the next mating season.
Aardvarks are distributed across most of sub-Saharan Africa, and although killed by humans both for their flesh and for their teeth (which are used as decorations), do not appear to be threatened.
Similar animals
- The anteaters of South America.
- Pangolins are also called scaly anteaters.
- The Numbat (Myrmecobius fasciatus), a marsupial, formerly called the Banded Anteater.
- Echidnas, a family of monotremes, are still sometimes called spiny anteaters.
- Armadillos are omnivorous but ants form a large part of their diet.
The word aardvark in comedy
The word aardvark is frequently used in comedy, being considered an inherently funny word.
British comedians John Cleese and Graham Chapman wrote a Bookshop Skit (for At Last the 1948 Show), in which a customer, initially played by Marty Feldman, seeks out a book called Ethel the Aardvark goes Quantity Surveying. This classic skit was subsequently performed on stage by Monty Python cast members.
In one episode of the British TV series Blackadder the Third, featuring the first appearance of Doctor Johnson's Dictionary, Edmund Blackadder notices that the word aardvark is missing from the manuscript. (Edmund had earlier come up with his own definition: "Medium-sized insectivore with protruding nasal implement.") Surprisingly, Blackadder is historically correct in this regard. Doctor Johnson's Dictionary does not in fact contain the word aardvark. Or sausage.
Cerebus the Aardvark is the eponymous anti-hero of a long-running satirical comic by Dave Sim.