Generalities
The aardvark - Orycteropus afer - is the only living species of the order Tubulidentata, family Orycteropodidae; it is thus the only mammalian order to contain a single extant species. The name Tubulidentata means "tube of teeth" and refers to the unique microstructure of its teeth. Indeed, each tooth consists of thousands of vertical tubes of dentine agglutinated. The genus name - Orycteropus - means "digging foot" (see Lehmann, 2007).
Aardvarks are sparsely scattered throughout the sub-Saharan parts of Africa. It has been suggested that the Egyptian God Seth was associated with the aardvark (Frechkop, 1946). This would therefore imply that aardvarks occurred in northern Africa in historical time. Rarely seen, these solitary nocturnal creatures roam the savannah plains night after night in search of ants or a tasty termite mound to help satisfy their huge appetites. But aardvarks have also been spotted in the forest of Gabon (e.g. Pagès, 1970). There are 18 doubtful sub-species of extant aardvark but little is known about the actual intra-specific variability (or polymorphism) of Orycteropus afer (see Shoshani et al., 1988, Lehmann, 2006).
Fossil aardvarks are known since 20 million of years from Africa (Kenya). Besides, numerous extinct species, aged between 15 and 3 million of years, have also been discovered in Europe and Asia. The biodiversity of aardvark was more important in the past than presently with up to four genera described (Lehmann, 2006). Recent genetic studies (now more and more supported by morphological and palaeontological studies) have suggested that aardvarks are closely related to the dassies (hyraxes), elephants (proboscideans), golden-moles (chrysoclorids), manatees and dugongs (sirenians), tenrecs, and more closely the elephant shrews (macroscelids) (e.g. Stanhope et al., 1998; Springer & Murphy, 2007; Nishihara et al., 2007).
Aardvark are not listed by CITES and are considered as Least Threatened by the IUCN, although it is agreed that this situation is mostly due to a lack of information. The ecological importance of the aardvark begins to be understood, but as their natural habitat declines in some region, a simple, yet integrated system may be lost.
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