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{{Short description|Burrowing mammal native to Africa}}
The '''Aardvark''' is a [[mammal]] of order ''[[Tubulidentata]]'', genus ''Orycteropus''.
{{Other uses}}
{{pp|small=yes}}
{{Use dmy dates|date=July 2020}}
{{Speciesbox
| fossil_range = {{Fossil range|5|0|Early [[Pliocene]] – Recent}}
| image = Orycteropus afer 175359469.jpg
| image_caption = Aardvark in the [[Bushveld]], Limpopo
| image2 = Aardvark (Orycteropus afer).jpg
| image2_caption = At [[Royal Burgers' Zoo]], Arnhem, Netherlands
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name="iucn status 12 November 2021">{{cite iucn |author=Taylor, A. |author2=Lehmann, T. |date=2015 |title=''Orycteropus afer'' |volume=2015 |page=e.T41504A21286437 |doi=10.2305/IUCN.UK.2015-2.RLTS.T41504A21286437.en |access-date=12 November 2021}}</ref>
| genus = Orycteropus
| species = afer
| authority = ([[Peter Simon Pallas|Pallas]], 1766)
| subdivision_ranks = Subspecies
| subdivision = See text
| range_map = Aardvark area.png
| range_map_caption = Aardvark range
| range_map_alt = Map of Africa showing a highlighted range (in green) covering most of the continent south of the Sahara desert
}}
[[File:Aardvark Skeleton.jpg|thumb|Skeleton of an aardvark]]
'''Aardvarks''' ({{IPAc-en|ˈ|ɑːr|d|v|ɑːr|k|}} {{respell|ARD|vark}}; '''''Orycteropus afer''''') are medium-sized, burrowing, [[nocturnal]] mammals native to Africa.<ref name="EB">{{harvnb|Hoiberg|2010|pp=3–4}}</ref><ref>[https://www.dsae.co.za/entry/aardvark/e00015 "Aardvark, n."] ''Dictionary of South African English''. Dictionary Unit for South African English, 2018. 26 February 2019.</ref> They have a long snout, similar to that of a pig, which is used to sniff out food.


Aardvarks are the only living [[species]] of the order [[Tubulidentata]],<ref name="MSW3">{{harvnb|Schlitter|2005|p=86}}</ref><ref name="EoM" /> although other prehistoric species and genera of Tubulidentata are known. They are [[afrothere]]s, a [[clade]] that also includes [[elephants]], [[manatees]], and [[hyraxes]].
The name comes from [[Dutch]] for "earth pig".
Aardvarks are native to [[Africa]].


They are found over much of the southern two-thirds of the African continent, avoiding areas that are mainly rocky. Nocturnal feeders, aardvarks subsist on ants and termites by using their sharp claws and powerful legs to dig the insects out of their hills. Aardvarks also dig to create burrows in which to live and rear their young.
Several species have been named. Among them
is the typical form, ''O. capensis'', or Cape ant-bear from
[[South Africa]], and the northern aardvark (''O. aethiopicus'')
of northeastern Africa, extending into [[Egypt]].


Aardvarks are listed as "least concern" by the [[IUCN]], although their numbers are decreasing.
In form these animals are somewhat pig-like; the body is stout,
with arched back; the limbs are short and stout, armed with
strong, blunt claws; the ears disproportionately long; and
the tail very thick at the base and tapering gradually. The
greatly elongated head is set on a short thick neck, and at
the extremity of the snout is a disk in which the nostrils
open. The mouth is small and tubular, furnished with a long
extensile tongue. The measurements of a female taken in the
flesh, were head and body 4 feet, tail 17 1/2 inches; but a large
individual measured 6 feet 8 inches over all. In colour the
Cape aardvark is pale sandy or yellow, the hair being scanty
and allowing the skin to show; the northern aardvark has
a still thinner coat, and is further distinguished by the
shorter tail and longer head and ears.


==Name and taxonomy==
Aardvarks are nocturnal animals. Although named for eating ants,
they actually eat termites. They burrow into termite mounds using
their strong claws, and the insects are collected on their long
tongue. The aardvark should not be confused with the [[anteater]].


=== Name ===
-----
The aardvark is sometimes colloquially called the "African ant bear",<ref name="Colliers">{{harvnb|Goodwin|1997|pp=2–3}}</ref> "anteater" (not to be confused with the [[anteater|South American anteaters]]), or the "Cape anteater"<ref name=Colliers/> after the [[Cape of Good Hope]].
Text originally from a 1911 Encyclopedia that is now in the public
domain, and whose trademark owners do not want us to name it.


The name "aardvark" is [[Afrikaans]] ({{IPA|af|ˈɑːrtfark|pron}}) and comes from earlier Afrikaans {{Lang|af|erdvark}}.<ref name=Colliers/> It means "earth [[pig]]" or "ground pig" ({{lang|af|aarde}}: {{gloss|earth}}, {{lang|af|vark}}: {{gloss|pig, young pig}}), because of its burrowing habits.<ref>{{harvnb|Merriam-Webster Online Dictionary|2010}}</ref><ref>{{Cite OED|term=aardvark|date=March 2018|id=22|access-date=24 May 2018}}</ref><ref>{{Cite dictionary |url=https://www.dsae.co.za/entry/aardvark/e00015 |title=aardvark |encyclopedia=Dictionary of South African English |publisher=Dictionary Unit for South African English |year=2018 |access-date=25 February 2019}}</ref>
The text here has been updated by Wikipedians, perhaps significantly.

----
The name ''Orycteropus'' means "burrowing foot", and the name ''afer'' refers to Africa.<ref name=sho/> The name of the aardvark's order, ''Tubulidentata,'' comes from the tubule-style teeth.<ref name=sho1>{{harvnb|Shoshani|2002|p=619}}</ref>
British comedians [[John Cleese]] and [[Graham Chapman]] wrote a

Bookshop Skit in which a customer, initially [[Marty Feldman]],
=== Taxonomy ===
seeks out a book called "Ethel the Aardvark goes Quantity Surveying".
[[File:Aardvark skull.JPG|thumb|Skull of an aardvark]]
This classic skit was subsequently performed on stage by
The aardvark is not closely related to the pig; rather, it is the sole extant representative of the obscure mammalian [[order (biology)|order]] [[Tubulidentata]],<ref name=sho>{{harvnb|Shoshani|2002|p=618}}</ref> in which it is usually considered to form one variable species of the genus ''[[Orycteropus]]'', the sole surviving genus in the family [[Orycteropodidae]]. The aardvark is not closely related to the [[South America]]n [[anteater]], despite sharing some characteristics and a superficial resemblance.<ref name=awf/> The similarities are the outcome of [[convergent evolution]].<ref name=UR2/> The closest living relatives of the aardvark are the [[elephant shrew]]s, [[tenrecidae]], and [[golden mole]]s.<ref>{{harvnb|Asher|Bennett|Lehmann|2009|p=854}}</ref> Along with [[sirenian]]s, [[hyrax]]es, [[elephant]]s,<ref>{{harvnb|Rodriguez|2013|p=6}}</ref> and their extinct relatives, these animals form the superorder [[Afrotheria]].<ref name=UR>{{harvnb|Rahm|1990|pp=450–451}}</ref> Studies of the brain have shown the similarities with [[Condylarthra]].<ref name=UR2/>
[[Monty Python]] cast members.

=== Evolutionary history ===
Based on his study of fossils, [[Bryan Patterson]] has concluded that early relatives of the aardvark appeared in [[Africa]] around the end of the [[Paleocene]].<ref name=UR2/><ref name=sho2>{{harvnb|Shoshani|2002|p=620}}</ref> The [[ptolemaiida]]ns, a mysterious clade of mammals with uncertain affinities, may actually be stem-aardvarks, either as a sister clade to [[Tubulidentata]] or as a grade leading to true tubulidentates.<ref name="Cote et al 2007">{{cite journal |vauthors=Cote S, Werdelin L, Seiffert ER, Barry JC |title=Additional material of the enigmatic Early Miocene mammal ''Kelba'' and its relationship to the order Ptolemaiida |journal=Proc Natl Acad Sci USA |volume=104 |issue=13 |pages=5510–5 |date=March 2007 |pmid=17372202 |pmc=1838468 |doi=10.1073/pnas.0700441104 |bibcode = 2007PNAS..104.5510C |doi-access=free }}</ref><ref name=Seifert2007>{{cite journal|last=Seiffert|first=Erik R|title=A new estimate of afrotherian phylogeny based on simultaneous analysis of genomic, morphological, and fossil evidence|journal=BMC Evolutionary Biology|year=2007|volume=7|issue=1|pages=224|doi=10.1186/1471-2148-7-224 |doi-access=free|url= |pmid=17999766|pmc=2248600|bibcode=2007BMCEE...7..224S }}</ref>

The first unambiguous tubulidentate was probably ''[[Myorycteropus africanus]]'' from [[Kenya]]n [[Miocene]] deposits.<ref name=UR2/> The earliest example from the genus ''[[Orycteropus]]'' was ''[[Amphiorycteropus|Orycteropus mauritanicus]]'', found in [[Algeria]] in deposits from the middle Miocene, with an equally old version found in Kenya.<ref name=UR2/> Fossils from the aardvark have been dated to 5 million years, and have been located throughout [[Europe]] and the [[Near East]].<ref name=UR2/>

The mysterious Pleistocene ''[[Plesiorycteropus]]'' from [[Madagascar]] was originally thought to be a tubulidentate that was descended from ancestors that entered the island during the [[Eocene]]. However, a number of subtle anatomical differences coupled with recent molecular evidence now lead researchers to believe that ''Plesiorycteropus'' is a relative of golden moles and [[Tenrec|tenrecs]] that achieved an aardvark-like appearance and ecological niche through convergent evolution.<ref>{{cite journal|doi=10.1371/journal.pone.0059614 |title=A Molecular Phylogeny of Plesiorycteropus Reassigns the Extinct Mammalian Order 'Bibymalagasia'|year=2013|last1=Buckley|first1=Michael|journal=PLOS ONE|volume=8|issue=3|pages=e59614|pmid=23555726|pmc=3608660|bibcode=2013PLoSO...859614B|doi-access=free}}</ref>

===Subspecies===
The aardvark has seventeen poorly defined subspecies listed:<ref name="MSW3"/>

* ''[[Orycteropus afer afer]]'' (Southern aardvark)
* ''O. a. adametzi'' <small> Grote, 1921</small> (Western aardvark)
* ''O. a. aethiopicus'' <small> [[Carl Jakob Sundevall|Sundevall]], 1843</small>
* ''O. a. angolensis'' <small> Zukowsky & [[Theodor Haltenorth|Haltenorth]], 1957</small>
* ''O. a. erikssoni'' <small> [[Einar Lönnberg|Lönnberg]], 1906</small>
* ''O. a. faradjius'' <small> Hatt, 1932</small>
* ''O. a. haussanus'' <small> [[Paul Matschie|Matschie]], 1900</small>
* ''O. a. kordofanicus'' <small> [[Walter Rothschild, 2nd Baron Rothschild|Rothschild]], 1927</small>
* ''O. a. lademanni'' <small> Grote, 1911</small>
* ''O. a. leptodon'' <small> Hirst, 1906</small>
* ''O. a. matschiei'' <small> Grote, 1921</small>
* ''O. a. observandus'' <small>Grote, 1921</small>
* ''O. a. ruvanensis'' <small>Grote, 1921</small>
* ''O. a. senegalensis'' <small>[[René Primevère Lesson|Lesson]], 1840</small>
* ''O. a. somalicus'' <small>[[Richard Lydekker|Lydekker]], 1908</small>
* ''O. a. wardi'' <small>Lydekker, 1908</small>
* ''O. a. wertheri'' <small> Matschie, 1898</small> (Eastern aardvark)

The [[1911 Encyclopædia Britannica]] also mentions ''O.&nbsp;a. capensis'' or Cape ant-bear from South Africa.<ref>{{cite EB1911|wstitle=Aard-vark|volume=1|page=2}}</ref>

== Description ==
{{Multiimage
| image1 = Orycteropus afer 175359476.jpg
| image2 = Southern Aardvark foot print.jpg
| direction = vertical
| align = left
| caption2 = Southern aardvark (''O.{{nbsp}}a. afer'') front and rear foot print
}}
[[File:Ulna radius of aardvark.jpg|thumb|Strong forelimb of aardvark]]

The aardvark is vaguely pig-like in appearance. Its body is stout with a prominently arched back<ref name="UR1">{{harvnb|Rahm|1990|p=452}}</ref> and is sparsely covered with coarse hairs. The limbs are of moderate length, with the rear legs being longer than the forelegs.<ref name="UR" /> The front feet have lost the pollex (or 'thumb'), resulting in four toes, while the rear feet have all five toes. Each toe bears a large, robust [[Nail (anatomy)|nail]] which is somewhat flattened and shovel-like, and appears to be intermediate between a [[claw]] and a hoof. Whereas the aardvark is considered [[digitigrade]], it appears at times to be [[plantigrade]]. This confusion happens because when it squats it stands on its soles.<ref name="UR1" /> A contributing characteristic to the burrow digging capabilities of aardvarks is an endosteal tissue called compacted coarse cancellous bone (CCCB). The stress and strain resistance provided by CCCB allows aardvarks to create their burrows, ultimately leading to a favourable environment for plants and a variety of animals.<ref>{{cite journal |last1=Legendre |first1=Lucas J. |last2=Botha-Brink |first2=Jennifer |title=Digging the compromise: investigating the link between limb bone histology and fossoriality in the aardvark (Orycteropus afer) |journal=PeerJ |date=11 July 2018 |volume=6 |pages=e5216 |doi=10.7717/peerj.5216 |doi-access=free |pmid=30018860 |pmc=6045922 }}</ref><ref>{{cite journal |last1=Haussmann |first1=Natalie S. |last2=Louw |first2=Michelle A. |last3=Lewis |first3=Simone |last4=Nicol |first4=Keegan J. H. |last5=van der Merwe |first5=Stephni |last6=le Roux |first6=Peter C. |title=Ecosystem engineering through aardvark (Orycteropus afer) burrowing: Mechanisms and effects |journal=Ecological Engineering |date=1 August 2018 |volume=118 |pages=66–72 |doi=10.1016/j.ecoleng.2018.04.022 |bibcode=2018EcEng.118...66H |hdl=2263/65084 |s2cid=104179393 |hdl-access=free }}</ref> Digging is also facilitated by its forearm's unusually stout ulna and radius.<ref>{{Cite journal |last1=Legendre |first1=Lucas J. |last2=Botha-Brink |first2=Jennifer |date=2018-07-11 |title=Digging the compromise: investigating the link between limb bone histology and fossoriality in the aardvark ( Orycteropus afer ) |journal=PeerJ |language=en |volume=6 |pages=e5216 |doi=10.7717/peerj.5216 |doi-access=free |issn=2167-8359 |pmc=6045922 |pmid=30018860}}</ref><ref>{{Cite web |title=Aardvark Forelimb and Scapula - Wits University |url=https://www.wits.ac.za/wits-life-sciences-museum/aardvark-forelimb-and-scapula/ |access-date=2024-09-29 |website=www.wits.ac.za}}</ref>[[File:Aardvark skeleton mount.JPG|thumb|right|An aardvark skeleton and mounted individual]]An aardvark's weight is typically between {{convert|60|and(-)|80|kg}}.<ref name="UR" /> An aardvark's length is usually between {{convert|105|and(-)|130|cm|ft}},<ref name="EoM" /> and can reach lengths of {{convert|2.2|m}} when its tail (which can be up to {{convert|70|cm}}) is taken into account. It is {{convert|60|cm|in}} tall at the shoulder, and has a girth of about {{convert|100|cm|ft}}.<ref name="UR1" /> It is the [[Largest organisms|largest]] member of the proposed clade [[Afroinsectiphilia]]. The aardvark is pale yellowish-grey in colour and often stained reddish-brown by [[soil]]. The aardvark's coat is thin, and the animal's primary protection is its tough skin. Its hair is short on its head and tail; however its legs tend to have longer hair.<ref name="EoM" /> The hair on the majority of its body is grouped in clusters of 3–4 hairs.<ref name="UR1" /> The hair surrounding its nostrils is dense to help filter particulate matter out as it digs. Its tail is very thick at the base and gradually tapers.

===Head===
The greatly elongated head is set on a short, thick neck, and the end of the snout bears a disc, which houses the nostrils. It contains a thin but complete [[zygomatic arch]].<ref name=UR1/> The head of the aardvark contains many unique and different features. One of the most distinctive characteristics of the Tubulidentata is their [[Tooth|teeth]]. Instead of having a [[pulp (tooth)|pulp cavity]], each tooth has a cluster of thin, hexagonal, upright, parallel tubes of vasodentin (a modified form of [[dentine]]), with individual pulp canals, held together by [[cementum]].<ref name=UR/> The number of columns is dependent on the size of the tooth, with the largest having about 1,500.<ref name=UR2/> The teeth have no [[Tooth enamel|enamel]] coating and are worn away and regrow continuously.<ref name=sho1/> The aardvark is born with conventional incisors and [[canine tooth|canines]] at the front of the jaw, which fall out and are not replaced. Adult aardvarks have only cheek teeth at the back of the [[jaw]], and have a [[dentition|dental formula]] of: {{DentalFormula|upper=0.0.2-3.3|lower=0.0.2.3}} These remaining teeth are peg-like and rootless and are of unique composition.<ref>{{harvnb|Martin|1983|p=377}}</ref> The teeth consist of 14 upper and 12 lower jaw molars.<ref name=Colliers/> The nasal area of the aardvark is another unique area, as it contains ten [[nasal concha]]e, more than any other placental mammal.<ref name=UR/>

The sides of the nostrils are thick with hair.<ref name=UR1/> The tip of the snout is highly mobile and is moved by modified [[mimetic muscles]].<ref name=UR/> The fleshy dividing tissue between its nostrils probably has sensory functions,<ref name=EoM/> but it is uncertain whether they are olfactory or vibratory in nature.<ref name=UR6>{{harvnb|Rahm|1990|p=458}}</ref> Its nose is made up of more [[turbinate]] bones than any other mammal, with between 9 and 11, compared to dogs with 4 to 5.<ref name=sho1/> With a large quantity of turbinate bones, the aardvark has more space for the moist [[epithelium]], which is the location of the olfactory bulb.<ref name=sho1/> The nose contains nine [[olfactory bulb]]s, more than any other mammal.<ref name=UR1/> Its keen sense of smell is not just from the quantity of bulbs in the nose but also in the development of the brain, as its [[Olfactory bulb|olfactory lobe]] is very developed.<ref name=UR2>{{harvnb|Rahm|1990|pp=453–454}}</ref> The snout resembles an elongated pig snout. The mouth is small and tubular, typical of species that feed on [[ant]]s and [[termite]]s. The aardvark has a long, thin, snakelike, protruding tongue (as much as {{convert|30|cm|in}} long)<ref name=Colliers/> and elaborate structures supporting a keen [[olfaction|sense of smell]].<ref name="TaylorSkinner">{{harvnb|Taylor|Skinner|2004|p=106}}</ref> The ears, which are very effective,<ref name=Colliers/> are disproportionately long, about {{convert|20|-|25|cm|in}} long.<ref name=UR1/> The eyes are small for its head, and consist only of [[rod cell|rods]].<ref name=UR1/>

===Digestive system===
The aardvark's stomach has a muscular [[pyloric]] area that acts as a [[gizzard]] to grind swallowed food up, thereby rendering chewing unnecessary.<ref name=EoM/> Its [[cecum]] is large.<ref name=UR/> Both sexes emit a strong smelling secretion from an anal gland.<ref name=EoM/> Its [[salivary gland]]s are highly developed and almost completely ring the neck;<ref name=UR/> their output is what causes the tongue to maintain its tackiness.<ref name=UR1/> The female has two pairs of [[teat]]s in the inguinal region.<ref name=UR/>

[[Gene]]tically speaking, the aardvark is a [[living fossil]], as its [[chromosome]]s are highly conserved, reflecting much of the early [[eutherian]] arrangement before the divergence of the major modern [[taxon|taxa]].<ref>{{harvnb|Anon|2003}}</ref>

==Habitat and range==
Aardvarks are found in [[sub-Saharan Africa]], where suitable [[habitat]] ([[savanna]]s, [[grassland]]s, [[woodland]]s and [[bushland]]) and food (i.e., [[ants]] and [[termites]]) is available.<ref name="awf">{{harvnb|African Wildlife Foundation|2013}}</ref> They spend the daylight hours in dark burrows to avoid the heat of the day.<ref name=ez>{{harvnb|Anon|2013}}</ref> The only major habitat that they are not present in is swamp forest, as the high water table precludes digging to a sufficient depth.<ref name="iucn status 12 November 2021" /> They also avoid terrain rocky enough to cause problems with digging.<ref name=UR3>{{harvnb|Rahm|1990|p=455}}</ref> They have been documented as high as {{convert|3200|m|ft}} in Ethiopia. They are present throughout sub-Saharan Africa all the way to South Africa with few exceptions including the coastal areas of [[Namibia]], [[Ivory Coast]], and [[Ghana]]. They are not found in Madagascar.<ref name="iucn status 12 November 2021" />

==Ecology and behaviour==
[[File:Orycteropus afer.jpg|thumb|upright|right|Aardvark resting]]
[[File:Erdvarkgat, Dingaanstat.jpg|thumb|right|Entrance to a burrow]]
[[File:SanWild17.jpg|thumb|right|Emerging from a burrow]]
Aardvarks live for up to 23&nbsp;years in [[captivity (animal)|captivity]].<ref name=UR/> Its keen hearing warns it of predators: [[lion]]s, [[leopard]]s, cheetahs, [[African wild dog]]s, [[hyena]]s, and [[pythonidae|pythons]].<ref name=Colliers/><ref name=UR6/> Some humans also hunt aardvarks for meat.<ref name=Colliers/> Aardvarks can dig fast or run in zigzag fashion to elude enemies, but if all else fails, they will strike with their claws, tail and shoulders, sometimes flipping onto their backs lying motionless except to lash out with all four feet.<ref name=UR6/> They are capable of causing substantial damage to unprotected areas of an attacker.<ref name=sho1/> They will also dig to escape as they can. Sometimes, when pressed, aardvarks can dig extremely quickly.<ref name=UR6/>

=== Feeding ===
[[File:Southern Aardvark 1.jpg|left|thumb|The unusual cross-walk gait of the aardvark]]
The aardvark is [[nocturnal]] and is a solitary creature that feeds almost exclusively on [[ant]]s and [[termite]]s ([[myrmecophagy]]);<ref name="EoM">{{harvnb|van Aarde|1984|pp=466–467}}</ref> the only fruit eaten by aardvarks is the [[aardvark cucumber]].<ref name=UR6/> In fact, the cucumber and the aardvark have a symbiotic relationship as they eat the subterranean fruit, then defecate the seeds near their burrows, which then grow rapidly due to the loose soil and fertile nature of the area. The time spent in the intestine of the aardvark helps the fertility of the seed, and the fruit provides needed moisture for the aardvark.<ref name=sho1/><ref name=UR6/> They avoid eating the African [[driver ant]] and red ants.<ref name=UR4/> Due to their stringent diet requirements, they require a large range to survive.<ref name=UR3/> An aardvark emerges from its burrow in the late afternoon or shortly after sunset, and forages over a considerable home range encompassing {{convert|10|to|30|km|mi}}. While foraging for food, the aardvark will keep its nose to the ground and its ears pointed forward, which indicates that both smell and hearing are involved in the search for food. They zig-zag as they forage and will usually not repeat a route for 5–8 days as they appear to allow time for the termite nests to recover before feeding on it again.<ref name=UR4/>

During a foraging period, they will stop to dig a V-shaped trench with their forefeet and then sniff it profusely as a means to explore their location.<ref name=EoM/> When a concentration of ants or termites is detected, 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 [[insect]]s with its long, sticky tongue—as many as 50,000 in one night have been recorded. Its claws enable it to dig through the extremely hard crust of a termite or ant mound quickly. It avoids inhaling the dust by sealing the nostrils.<ref name=ez/> When successful, the aardvark's long (up to {{convert|30|cm|in}})<ref name=EB/> tongue licks up the insects; the termites' biting, or the ants' stinging attacks are rendered futile by the tough skin. After an aardvark visit at a termite mound, other animals will visit to pick up all the leftovers.<ref name=UR5>{{harvnb|Rahm|1990|p=457}}</ref> Termite mounds alone do not provide enough food for the aardvark, so they look for termites that are on the move. When these insects move, they can form columns {{convert|10|-|40|m|ft}} long and these tend to provide easy pickings with little effort exerted by the aardvark. These columns are more common in areas of livestock or other hoofed animals.<ref name=UR5/> The trampled grass and dung attract termites from the ''[[Odontotermes]]'', ''[[Microtermes]]'', and ''[[Pseudacanthotermes]]'' genera.<ref name=UR5/>

On a nightly basis they tend to be more active during the first portion of night (roughly the four hours between 8:00{{nbsp}}p.m. and 12:00{{nbsp}}a.m.); however, they do not seem to prefer bright or dark nights over the other. During adverse weather or if disturbed they will retreat to their burrow systems. They cover between {{convert|2|and|5|km|mi}} per night; however, some studies have shown that they may traverse as far as {{convert|30|km|mi}} in a night.<ref name=EoM/>

Aardvarks shift their circadian rhythms to more diurnal activity patterns in response to a reduced food supply. This survival tactic may signify an increased risk of imminent mortality.<ref>{{Cite journal |last1=Weyer |first1=Nora Marie |last2=Fuller |first2=Andrea |last3=Haw |first3=Anna Jean |last4=Meyer |first4=Leith Carl Rodney |last5=Mitchell |first5=Duncan |last6=Picker |first6=Mike |last7=Rey |first7=Benjamin |last8=Hetem |first8=Robyn Sheila |date=2020 |title=Increased Diurnal Activity Is Indicative of Energy Deficit in a Nocturnal Mammal, the Aardvark |journal=Frontiers in Physiology |volume=11 |page=637 |doi=10.3389/fphys.2020.00637 |issn=1664-042X |pmc=7358442 |pmid=32733261|doi-access=free |bibcode=2020FrPhs..11..637W }}</ref>

===Vocalisation===
The aardvark is a rather quiet animal. However, it does make soft grunting sounds as it forages and loud grunts as it makes for its tunnel entrance.<ref name=UR3/> It makes a bleating sound if frightened.<ref name=UR4>{{harvnb|Rahm|1990|p=456}}</ref> When it is threatened it will make for one of its burrows. If one is not close it will dig a new one rapidly. This new one will be short and require the aardvark to back out when the coast is clear.<ref name=UR4/>

===Movement===
The aardvark is known to be a good swimmer and has been witnessed successfully swimming in strong currents.<ref name=UR4/> It can dig a yard of tunnel in about five minutes,<ref name=UR3/> but otherwise moves fairly slowly.

When leaving the burrow at night, they pause at the entrance for about ten minutes, sniffing and listening. After this period of watchfulness, it will bound out and within seconds it will be {{convert|10|m|ft}} away. It will then pause, prick its ears, twisting its head to listen, then jump and move off to start foraging.<ref name=UR3/>

Aside from digging out ants and termites, the aardvark also [[fossorial|excavates]] burrows in which to live, which generally fall into one of three categories: burrows made while foraging, refuge and resting location, and permanent homes.<ref name=EoM/> Temporary sites are scattered around the home range and are used as refuges, while the main [[burrow]] is also used for breeding. Main burrows can be deep and extensive, have several entrances and can be as long as {{convert|13|m|ft}}.<ref name=EoM/> These burrows can be large enough for a person to enter.<ref name=Colliers/> The aardvark changes the layout of its home burrow regularly, and periodically moves on and makes a new one. The old burrows are an important part of the African wildlife scene. As they are vacated, then they are inhabited by smaller animals like the [[African Wild Dog|African wild dog]], [[ant-eating chat]], ''[[Nycteris thebaica]]'' and [[warthog]]s.<ref name=UR4/> Other animals that use them are hares, mongooses, hyenas, owls, pythons, and lizards. Without these refuges many animals would die during wildfire season.<ref name=UR4/> Only mothers and young share burrows; however, the aardvark is known to live in small family groups or as a solitary creature.<ref name=Colliers/> If attacked in the tunnel, it will escape by digging out of the tunnel thereby placing the fresh fill between it and its predator, or if it decides to fight it will roll onto its back, and attack with its claws.<ref name=Colliers/> The aardvark has been known to sleep in a recently excavated [[ant]] nest, which also serves as protection from its [[predator]]s.<ref>{{harvnb|Anon|2013a}}</ref>

===Reproduction===
[[File:Aardvarks.jpg|thumb|right|Aardvark mother and young]]
Aardvarks pair only during the breeding season; after a [[gestation]] period of seven months,<ref name=EoM/> one cub weighing around {{convert|1.7|-|1.9|kg|lb}}<ref name=UR/> is born during May–July.<ref name=Colliers/> When born, the young has flaccid ears and many wrinkles. When nursing, it will nurse off each teat in succession.<ref name=UR6/> After two weeks, the folds of skin disappear and after three, the ears can be held upright.<ref name=UR6/> After 5–6 weeks, body hair starts growing.<ref name=UR6/> It is able to leave the burrow to accompany its mother after only two weeks and eats termites at 9&nbsp;weeks,<ref name=UR6/> and is weaned between three months<ref name=UR/> and 16&nbsp;weeks.<ref name=EoM/> At six months of age, it is able to dig its own burrows, but it will often remain with the mother until the next [[mating season]],<ref name=EoM/> and is sexually mature from approximately two years of age.<ref name=UR/>

==Conservation==
Aardvarks were thought to have declining numbers,<ref name=Colliers/> however, this is possibly because they are not readily seen.<ref name="iucn status 12 November 2021" /> There are no definitive counts because of their nocturnal and secretive habits; however, their numbers seem to be stable overall. They are not considered common anywhere in Africa, but due to their large range, they maintain sufficient numbers. There may be a slight decrease in numbers in eastern, northern, and western Africa. Southern African numbers are not decreasing. It has received an official designation from the IUCN as [[least concern]].<ref name="iucn status 12 November 2021" /> However, they are a species in a precarious situation, as they are so dependent on such specific food; therefore if a problem arises with the abundance of termites, the species as a whole would be affected drastically.<ref name=EoM/>

Recent research suggests that aardvarks may be particularly vulnerable to alterations in temperature caused by climate change. [[Drought]]s negatively impact the availability of termites and ants, which comprise the bulk of an aardvark's diet.<ref>{{Cite journal |last=Melton |first=Derek A. |date=June 1976 |title=The biology of aardvark (Tubulidentata-Orycteropodidae) |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2907.1976.tb00204.x |journal=Mammal Review |language=en |volume=6 |issue=2 |pages=75–88 |doi=10.1111/j.1365-2907.1976.tb00204.x |issn=0305-1838}}</ref> Nocturnal species faced with resource scarcity may increase their diurnal activity to spare the energy costs of staying warm at night, but this comes at the cost of withstanding high temperatures during the day. A study on aardvarks in the [[Kalahari Desert]] saw that five out of six aardvarks being studied perished following a drought.<ref>{{Cite journal |last1=Rey |first1=Benjamin |last2=Fuller |first2=Andrea |last3=Mitchell |first3=Duncan |last4=Meyer |first4=Leith C. R. |last5=Hetem |first5=Robyn S. |date=2017-07-31 |title=Drought-induced starvation of aardvarks in the Kalahari: an indirect effect of climate change |journal=Biology Letters |volume=13 |issue=7 |pages=20170301 |doi=10.1098/rsbl.2017.0301 |pmc=5543026 |pmid=28724691}}</ref> Aardvarks that survive droughts can take long periods of time to regain health and optimal thermoregulatory physiology, reducing the reproductive potential of the species.

Aardvarks handle captivity well. The first zoo to have one was [[London Zoo]] in 1869, which had an animal from [[South Africa]].<ref name=UR6/>

==Mythology and popular culture==
{{more citations needed|section|date = September 2020}}

[[File:AFR F-111 air to air refueling.jpg|thumb|200px|[[General Dynamics F-111 Aardvark|F-111 Aardvark]]]]
[[File:F-14A Tomcat of VF-114 in flight 1977.jpg|thumb|200px|[[F-14 Tomcat]] from VF-114 Aardvarks with the squadron mascot painted on the tail]]

In [[African folklore]], the aardvark is much admired because of its diligent quest for food and its fearless response to [[army ant|soldier ants]]. [[Hausa people|Hausa]] magicians make a charm from the heart, skin, forehead, and nails of the aardvark, which they then proceed to pound together with the root of a certain tree. Wrapped in a piece of skin and worn on the chest, the charm is said to give the owner the ability to pass through walls or roofs at night. The charm is said to be used by burglars and those seeking to visit young girls without their parents' permission.<ref>{{harvnb|Rebecca|2007}}</ref> Also, some tribes, such as the [[Mangbetu people|Margbetu]], [[Ayanda]], and [[Logo people|Logo]],<ref name=EoM/> will use aardvark teeth to make bracelets, which are regarded as good luck charms.<ref name=Colliers/> The meat, which has a resemblance to pork, is eaten in certain cultures.<ref name=EoM/> In the mythology of the [[Kingdom of Dagbon|Dagbon]] people of Ghana, the aardvark is believed to possess superpowers.<ref>{{Cite web |last=Blench |first=Roger |title=Aardvarks go shopping: Dagomba concepts of living things |url=https://www.academia.edu/12251649}}</ref> The [[Dagomba people|Dagombas]] believe this animal can transfigure into and interact with humans.

The ancient [[Egyptian mythology|Egyptian god]] [[Set (mythology)|Set]] is usually depicted with the head of an [[Set animal|unidentified animal]], whose similarity to an aardvark has been noted in scholarship.<ref>{{harvnb|te Velde|1997|p=13}}</ref>

The [[Arthur Read|titular character]] and his families from ''[[Arthur (TV series)|Arthur]]'', an animated television series for children based on a book series and produced by [[WGBH-TV|WGBH]], shown in more than 180 countries, is an aardvark.<ref>{{harvnb|WGBH|2013}}</ref> In the first book of the series, ''Arthur's Nose'' (1976), he has a long, aardvark-like nose,<ref>[https://www.thriftbooks.com/enwiki/w/arthurs-nose-an-arthur-adventure_marc-brown/317005/item/2746044/ Arthur's Nose], Thriftbooks; accessed 2020.09.29.</ref> but in later books, his face becomes more rounded.<ref>[https://www.thriftbooks.com/enwiki/w/arthurs-eyes-an-arthur-adventure_marc-brown/464241/item/15015689/ Arthur's Eyes], Thriftbooks; accesses 2020.09.29.</ref>

[[Otis the Aardvark]] was a puppet character used on [[Children's BBC]] programming.

An aardvark features as the antagonist in the cartoon ''[[The Ant and the Aardvark]]'' as well as in the Canadian animated series ''[[The Raccoons]]''.

The supersonic fighter-bomber [[General Dynamics F-111 Aardvark|F-111/FB-111]] was nicknamed the Aardvark because of its long nose resembling the animal. It also had similarities with its nocturnal missions flown at a very low level employing ordnance that could penetrate deep into the ground. In the US Navy, the squadron [[VF-114]] was nicknamed the Aardvarks, flying [[McDonnell Douglas F-4 Phantom II|F-4]]s and then [[Grumman F-14 Tomcat|F-14]]s. The squadron mascot was adapted from the animal in the comic strip ''[[B.C. (comic strip)#Animals and other non-human characters|B.C.]]'', which the F-4 was said to resemble.

''[[Cerebus the Aardvark]]'' is a 300-issue comic book series by Dave Sim.

==Footnotes==
{{Reflist}}

==References==
{{refbegin|2}}
* {{cite web | author = African Wildlife Foundation | title = Aardvark | publisher = African Wildlife Foundation | url = http://www.awf.org/content/wildlife/detail/aardvark | access-date = 18 November 2013 | archive-url = https://web.archive.org/web/20080105044436/http://www.awf.org/content/wildlife/detail/aardvark | archive-date = 5 January 2008 | url-status = live | year = 2013 }}
* {{cite web | author = Anon | title = All About Aardvarks | url = http://www.easyscienceforkids.com/all-about-aardvarks.html | website = Easy Science for Kids | publisher = Online Science Tutor for Kids | access-date = 18 November 2013 | year = 2013 | url-status = dead | archive-url = https://web.archive.org/web/20131111151040/http://www.easyscienceforkids.com/all-about-aardvarks.html | archive-date = 11 November 2013 }}
* {{cite web | author = Anon | website = Animal Corner | year = 2013a | title = Rainforest Aardvark | url = http://www.animalcorner.co.uk/rainforests/aardvark.html | access-date = 10 January 2014 | url-status = dead | archive-url = https://web.archive.org/web/20130726194347/http://www.animalcorner.co.uk/rainforests/aardvark.html | archive-date = 26 July 2013 }}
* {{cite news | author = Anon | title = Great Uncle Aardvark? | website = BBC News | date = 20 January 2003 | url = http://news.bbc.co.uk/2/hi/science/nature/2676377.stm | access-date = 18 November 2013 | archive-url = https://web.archive.org/web/20080207170352/http://news.bbc.co.uk/2/hi/science/nature/2676377.stm | archive-date = 7 February 2008 }}
* {{Cite journal | last1 = Asher | first1 = R. J. | last2 = Bennett | first2 = N. | last3 = Lehmann | first3 = T. | title = The new framework for understanding placental mammal evolution | journal = BioEssays | volume = 31 | issue = 8 | pages = 853–864 | year = 2009 | pmid = 19582725| doi = 10.1002/bies.200900053 | s2cid = 46339675 | doi-access = free }}
* {{cite encyclopedia | last1 = Goodwin | first1 = George G. | editor-last = Johnston | editor-first = Bernard | encyclopedia = Collier's Encyclopedia | title = Aardvark | edition = 1st | year = 1997 | publisher = P.F. Collier | volume = I: A to Ameland | location = New York, NY | isbn = 978-1571610935 }}
* {{cite encyclopedia | editor-last = Hoiberg | editor-first = Dale H. | encyclopedia = Encyclopædia Britannica | title = Aardvark | edition = 15th | year = 2010 | publisher = Encyclopædia Britannica Inc. | volume = I: A-ak Bayes | location = Chicago, IL | isbn = 978-1-59339-837-8 | url = https://archive.org/details/newencyclopaedia2009ency }}
* {{cite iucn |author=Taylor, A. |author2=Lehmann, T. |date=2015 |title=''Orycteropus afer'' |volume=2015 |page=e.T41504A21286437 |doi=10.2305/IUCN.UK.2015-2.RLTS.T41504A21286437.en |access-date=12 November 2021 |ref={{harvid|Lindsey|Cilliers|Griffin|Taylor|2008}}}}
* {{cite encyclopedia | last = Martin | first = Elizabeth A. | encyclopedia = MacMillan Dictionary of Life Sciences | title = Tubulidentata | isbn = 978-0333348673 | year = 1983 | edition = 2nd | publisher = MacMillan }}
* {{cite web | author = Merriam-Webster Online Dictionary | title = aardvark | year = 2010 | website = Merriam-Webster Online Dictionary | access-date = 18 November 2013 | url = http://www.merriam-webster.com/dictionary/aardvark }}
* {{cite encyclopedia | last = Rahm | first = Urs | editor-last = Parker | editor-first = Sybil P. | title = Tubulidentates: Aardvark | encyclopedia = Grzimek's Encyclopedia of Mammals | volume = 4 | publisher = McGraw-Hill Publishing Company | location = New York, NY | isbn = 978-0-07-909508-4 | year = 1990 | pages = [https://archive.org/details/grzimeksencyclop0005unse/page/450 450 458] | url = https://archive.org/details/grzimeksencyclop0005unse/page/450 }}
* {{cite web | author = Rebecca | title = Cute as a Button but a Pain in my Butt: The Aardvark | url = http://www.themagicalbuffet.com/Issues/Vol02_Iss07/Article_049.html | access-date = 18 November 2013 | archive-url = https://web.archive.org/web/20080117180543/http://www.themagicalbuffet.com/Issues/Vol02_Iss07/Article_049.html | archive-date = 17 January 2008 | url-status = live | year = 2007 }}
* {{cite journal | last = Rodriguez | first = Tommy | title = Technological Perspectives in Phylogeny Research: Revisiting Comparative Analysis of Complete Mitochondrial Genomes for Time-Extended Lineages | journal = Figshare | doi = 10.6084/m9.figshare.804317 | year = 2013 | pages = 1–9 }}
* {{MSW3 Tubulidentata | id = 11300004 }}
* {{cite encyclopedia | last = Shoshani | first = Jeheskel | editor-last = Robertson | editor-first = Sarah | title = Tubulidentata | encyclopedia = Encyclopedia of Life Sciences | year = 2002 | volume = 18: Svedberg, Theodor to Two-hybrid and Related Systems | publisher = Nature Publishing Group | location = London, UK | isbn = 978-1-56159-274-6 }}
* {{cite iucn |author1=Taylor, A. |author2=Lehmann, T. |date=2015 |title=''Orycteropus afer'' |volume=2015 |page=e.T41504A21286437 |doi=10.2305/IUCN.UK.2015-2.RLTS.T41504A21286437.en |access-date=6 September 2021}}
* {{cite journal | last1 = Taylor | first1 = W. A. | last2 = Skinner | first2 = J. D. | title = Adaptations of the Aardvark for Survival in the Karoo: A Review | journal = Transactions of the Royal Society of South Africa | volume = 59 | issue = 2 | year = 2004 | doi = 10.1080/00359190409519169 | pages = 105–108 | bibcode = 2004TRSSA..59..105T | s2cid = 83819929 }}
* {{cite book | last = te Velde | first = Henk | title = Seth, God of Confusion: A Study of His Role in Egyptian Mythology and Religion (Ancient Near East) | url = https://books.google.com/books?id=0po3AAAAIAAJ&pg=PA13 | year = 1997 | publisher = Brill Academic Pub | isbn = 978-9004054028 }}
* {{cite encyclopedia | last = van Aarde | first = Rudi J. | editor-last = Macdonald | editor-first = David | title = Aardvark | encyclopedia = The Encyclopedia of Mammals | year = 1984 | publisher = Facts on File Publications | location = New York, NY | isbn = 978-0-87196-871-5 | url = https://archive.org/details/encyclopediaofma00mals_0 }}
* {{cite web | author = WGBH | url = https://www.pbs.org/parents/Arthur/program/prog_summary.html | title = About the Program: "Arthur" | website = PBS.org | publisher = Public Broadcasting System | year = 2013 | access-date = 10 November 2018 | archive-date = 10 April 2019 | archive-url = https://web.archive.org/web/20190410083904/http://www.pbs.org/parents/arthur/program/prog_summary.html | url-status = dead }}
* {{cite web | title = aardvark | year = 2018 | website = Dictionary of South African English | access-date = 25 February 2019 | url = http://www.dsae.co.za/entry/aardvark/e00015 }}
{{refend}}

==External links==
{{Wikispecies|Orycteropus afer}}
{{Commons}}
* [http://www.afrotheria.net/index.php IUCN/SSC Afrotheria Specialist Group]
* [https://www.youtube.com/watch?v=1Z5OoBqqYsk A YouTube video introducing the Bronx Zoo's aardvarks]
* [[wikisource:File:Aardvark.pdf|"The Biology of the Aardvark (''Orycteropus afer'')"]] a diploma thesis (without images)
* [https://web.archive.org/web/20080414134457/http://www.tierseiten.com/roehrenzaehner/aardvark.pdf "The Biology of the Aardvark" (''Orycteropus afer'')"] the thesis with images
* {{Wikisource-inline|list=
** {{cite EB9 |wstitle = Aard-vark |volume= I | page=3 |short=1}}
** "[[s:Popular Science Monthly/Volume 14/March 1879/The Aard-Vark or Earth-Hog|The Aard-Vark or Earth-Hog]]" in ''[[Popular Science Monthly]]'', Vol. 14 (March 1879)
** {{Cite NSRW|wstitle=Aardvark |short=x |noicon=x}}
** {{Cite Collier's|wstitle=Aard-vark |short=x |noicon=x}}
}}

{{mammals}}
{{Taxonbar|from=Q46212}}
{{Authority control}}

[[Category:Orycteropus]]
[[Category:Mammals of Africa]]
[[Category:Xerophiles]]
[[Category:Myrmecophagous mammals]]
[[Category:Mammals described in 1766]]
[[Category:Extant Zanclean first appearances]]
[[Category:Taxa named by Peter Simon Pallas]]
[[Category:Afrikaans words and phrases]]

Latest revision as of 01:11, 30 October 2024

Aardvark
Temporal range: Early Pliocene – Recent
Aardvark in the Bushveld, Limpopo
At Royal Burgers' Zoo, Arnhem, Netherlands
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Tubulidentata
Family: Orycteropodidae
Genus: Orycteropus
Species:
O. afer
Binomial name
Orycteropus afer
(Pallas, 1766)
Subspecies

See text

Map of Africa showing a highlighted range (in green) covering most of the continent south of the Sahara desert
Aardvark range
Skeleton of an aardvark

Aardvarks (/ˈɑːrdvɑːrk/ ARD-vark; Orycteropus afer) are medium-sized, burrowing, nocturnal mammals native to Africa.[2][3] They have a long snout, similar to that of a pig, which is used to sniff out food.

Aardvarks are the only living species of the order Tubulidentata,[4][5] although other prehistoric species and genera of Tubulidentata are known. They are afrotheres, a clade that also includes elephants, manatees, and hyraxes.

They are found over much of the southern two-thirds of the African continent, avoiding areas that are mainly rocky. Nocturnal feeders, aardvarks subsist on ants and termites by using their sharp claws and powerful legs to dig the insects out of their hills. Aardvarks also dig to create burrows in which to live and rear their young.

Aardvarks are listed as "least concern" by the IUCN, although their numbers are decreasing.

Name and taxonomy

Name

The aardvark is sometimes colloquially called the "African ant bear",[6] "anteater" (not to be confused with the South American anteaters), or the "Cape anteater"[6] after the Cape of Good Hope.

The name "aardvark" is Afrikaans (pronounced [ˈɑːrtfark]) and comes from earlier Afrikaans erdvark.[6] It means "earth pig" or "ground pig" (aarde: 'earth', vark: 'pig, young pig'), because of its burrowing habits.[7][8][9]

The name Orycteropus means "burrowing foot", and the name afer refers to Africa.[10] The name of the aardvark's order, Tubulidentata, comes from the tubule-style teeth.[11]

Taxonomy

Skull of an aardvark

The aardvark is not closely related to the pig; rather, it is the sole extant representative of the obscure mammalian order Tubulidentata,[10] in which it is usually considered to form one variable species of the genus Orycteropus, the sole surviving genus in the family Orycteropodidae. The aardvark is not closely related to the South American anteater, despite sharing some characteristics and a superficial resemblance.[12] The similarities are the outcome of convergent evolution.[13] The closest living relatives of the aardvark are the elephant shrews, tenrecidae, and golden moles.[14] Along with sirenians, hyraxes, elephants,[15] and their extinct relatives, these animals form the superorder Afrotheria.[16] Studies of the brain have shown the similarities with Condylarthra.[13]

Evolutionary history

Based on his study of fossils, Bryan Patterson has concluded that early relatives of the aardvark appeared in Africa around the end of the Paleocene.[13][17] The ptolemaiidans, a mysterious clade of mammals with uncertain affinities, may actually be stem-aardvarks, either as a sister clade to Tubulidentata or as a grade leading to true tubulidentates.[18][19]

The first unambiguous tubulidentate was probably Myorycteropus africanus from Kenyan Miocene deposits.[13] The earliest example from the genus Orycteropus was Orycteropus mauritanicus, found in Algeria in deposits from the middle Miocene, with an equally old version found in Kenya.[13] Fossils from the aardvark have been dated to 5 million years, and have been located throughout Europe and the Near East.[13]

The mysterious Pleistocene Plesiorycteropus from Madagascar was originally thought to be a tubulidentate that was descended from ancestors that entered the island during the Eocene. However, a number of subtle anatomical differences coupled with recent molecular evidence now lead researchers to believe that Plesiorycteropus is a relative of golden moles and tenrecs that achieved an aardvark-like appearance and ecological niche through convergent evolution.[20]

Subspecies

The aardvark has seventeen poorly defined subspecies listed:[4]

  • Orycteropus afer afer (Southern aardvark)
  • O. a. adametzi Grote, 1921 (Western aardvark)
  • O. a. aethiopicus Sundevall, 1843
  • O. a. angolensis Zukowsky & Haltenorth, 1957
  • O. a. erikssoni Lönnberg, 1906
  • O. a. faradjius Hatt, 1932
  • O. a. haussanus Matschie, 1900
  • O. a. kordofanicus Rothschild, 1927
  • O. a. lademanni Grote, 1911
  • O. a. leptodon Hirst, 1906
  • O. a. matschiei Grote, 1921
  • O. a. observandus Grote, 1921
  • O. a. ruvanensis Grote, 1921
  • O. a. senegalensis Lesson, 1840
  • O. a. somalicus Lydekker, 1908
  • O. a. wardi Lydekker, 1908
  • O. a. wertheri Matschie, 1898 (Eastern aardvark)

The 1911 Encyclopædia Britannica also mentions O. a. capensis or Cape ant-bear from South Africa.[21]

Description

Southern aardvark (O. a. afer) front and rear foot print
Strong forelimb of aardvark

The aardvark is vaguely pig-like in appearance. Its body is stout with a prominently arched back[22] and is sparsely covered with coarse hairs. The limbs are of moderate length, with the rear legs being longer than the forelegs.[16] The front feet have lost the pollex (or 'thumb'), resulting in four toes, while the rear feet have all five toes. 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. Whereas the aardvark is considered digitigrade, it appears at times to be plantigrade. This confusion happens because when it squats it stands on its soles.[22] A contributing characteristic to the burrow digging capabilities of aardvarks is an endosteal tissue called compacted coarse cancellous bone (CCCB). The stress and strain resistance provided by CCCB allows aardvarks to create their burrows, ultimately leading to a favourable environment for plants and a variety of animals.[23][24] Digging is also facilitated by its forearm's unusually stout ulna and radius.[25][26]

An aardvark skeleton and mounted individual

An aardvark's weight is typically between 60 and 80 kilograms (130–180 lb).[16] An aardvark's length is usually between 105 and 130 centimetres (3.44–4.27 ft),[5] and can reach lengths of 2.2 metres (7 ft 3 in) when its tail (which can be up to 70 centimetres (28 in)) is taken into account. It is 60 centimetres (24 in) tall at the shoulder, and has a girth of about 100 centimetres (3.3 ft).[22] It is the largest member of the proposed clade Afroinsectiphilia. The aardvark is pale yellowish-grey in colour and often stained reddish-brown by soil. The aardvark's coat is thin, and the animal's primary protection is its tough skin. Its hair is short on its head and tail; however its legs tend to have longer hair.[5] The hair on the majority of its body is grouped in clusters of 3–4 hairs.[22] The hair surrounding its nostrils is dense to help filter particulate matter out as it digs. Its tail is very thick at the base and gradually tapers.

The greatly elongated head is set on a short, thick neck, and the end of the snout bears a disc, which houses the nostrils. It contains a thin but complete zygomatic arch.[22] The head of the aardvark contains many unique and different features. One of the most distinctive characteristics of the Tubulidentata is their teeth. Instead of having a pulp cavity, each tooth has a cluster of thin, hexagonal, upright, parallel tubes of vasodentin (a modified form of dentine), with individual pulp canals, held together by cementum.[16] The number of columns is dependent on the size of the tooth, with the largest having about 1,500.[13] The teeth have no enamel coating and are worn away and regrow continuously.[11] The aardvark is born with conventional incisors and canines at the front of the jaw, which fall out and are not replaced. Adult aardvarks have only cheek teeth at the back of the jaw, and have a dental formula of: 0.0.2-3.30.0.2.3 These remaining teeth are peg-like and rootless and are of unique composition.[27] The teeth consist of 14 upper and 12 lower jaw molars.[6] The nasal area of the aardvark is another unique area, as it contains ten nasal conchae, more than any other placental mammal.[16]

The sides of the nostrils are thick with hair.[22] The tip of the snout is highly mobile and is moved by modified mimetic muscles.[16] The fleshy dividing tissue between its nostrils probably has sensory functions,[5] but it is uncertain whether they are olfactory or vibratory in nature.[28] Its nose is made up of more turbinate bones than any other mammal, with between 9 and 11, compared to dogs with 4 to 5.[11] With a large quantity of turbinate bones, the aardvark has more space for the moist epithelium, which is the location of the olfactory bulb.[11] The nose contains nine olfactory bulbs, more than any other mammal.[22] Its keen sense of smell is not just from the quantity of bulbs in the nose but also in the development of the brain, as its olfactory lobe is very developed.[13] The snout resembles an elongated pig snout. The mouth is small and tubular, typical of species that feed on ants and termites. The aardvark has a long, thin, snakelike, protruding tongue (as much as 30 centimetres (12 in) long)[6] and elaborate structures supporting a keen sense of smell.[29] The ears, which are very effective,[6] are disproportionately long, about 20–25 centimetres (7.9–9.8 in) long.[22] The eyes are small for its head, and consist only of rods.[22]

Digestive system

The aardvark's stomach has a muscular pyloric area that acts as a gizzard to grind swallowed food up, thereby rendering chewing unnecessary.[5] Its cecum is large.[16] Both sexes emit a strong smelling secretion from an anal gland.[5] Its salivary glands are highly developed and almost completely ring the neck;[16] their output is what causes the tongue to maintain its tackiness.[22] The female has two pairs of teats in the inguinal region.[16]

Genetically speaking, the aardvark is a living fossil, as its chromosomes are highly conserved, reflecting much of the early eutherian arrangement before the divergence of the major modern taxa.[30]

Habitat and range

Aardvarks are found in sub-Saharan Africa, where suitable habitat (savannas, grasslands, woodlands and bushland) and food (i.e., ants and termites) is available.[12] They spend the daylight hours in dark burrows to avoid the heat of the day.[31] The only major habitat that they are not present in is swamp forest, as the high water table precludes digging to a sufficient depth.[1] They also avoid terrain rocky enough to cause problems with digging.[32] They have been documented as high as 3,200 metres (10,500 ft) in Ethiopia. They are present throughout sub-Saharan Africa all the way to South Africa with few exceptions including the coastal areas of Namibia, Ivory Coast, and Ghana. They are not found in Madagascar.[1]

Ecology and behaviour

Aardvark resting
Entrance to a burrow
Emerging from a burrow

Aardvarks live for up to 23 years in captivity.[16] Its keen hearing warns it of predators: lions, leopards, cheetahs, African wild dogs, hyenas, and pythons.[6][28] Some humans also hunt aardvarks for meat.[6] Aardvarks can dig fast or run in zigzag fashion to elude enemies, but if all else fails, they will strike with their claws, tail and shoulders, sometimes flipping onto their backs lying motionless except to lash out with all four feet.[28] They are capable of causing substantial damage to unprotected areas of an attacker.[11] They will also dig to escape as they can. Sometimes, when pressed, aardvarks can dig extremely quickly.[28]

Feeding

The unusual cross-walk gait of the aardvark

The aardvark is nocturnal and is a solitary creature that feeds almost exclusively on ants and termites (myrmecophagy);[5] the only fruit eaten by aardvarks is the aardvark cucumber.[28] In fact, the cucumber and the aardvark have a symbiotic relationship as they eat the subterranean fruit, then defecate the seeds near their burrows, which then grow rapidly due to the loose soil and fertile nature of the area. The time spent in the intestine of the aardvark helps the fertility of the seed, and the fruit provides needed moisture for the aardvark.[11][28] They avoid eating the African driver ant and red ants.[33] Due to their stringent diet requirements, they require a large range to survive.[32] An aardvark emerges from its burrow in the late afternoon or shortly after sunset, and forages over a considerable home range encompassing 10 to 30 kilometres (6.2 to 18.6 mi). While foraging for food, the aardvark will keep its nose to the ground and its ears pointed forward, which indicates that both smell and hearing are involved in the search for food. They zig-zag as they forage and will usually not repeat a route for 5–8 days as they appear to allow time for the termite nests to recover before feeding on it again.[33]

During a foraging period, they will stop to dig a V-shaped trench with their forefeet and then sniff it profusely as a means to explore their location.[5] When a concentration of ants or termites is detected, 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 have been recorded. Its claws enable it to dig through the extremely hard crust of a termite or ant mound quickly. It avoids inhaling the dust by sealing the nostrils.[31] When successful, the aardvark's long (up to 30 centimetres (12 in))[2] tongue licks up the insects; the termites' biting, or the ants' stinging attacks are rendered futile by the tough skin. After an aardvark visit at a termite mound, other animals will visit to pick up all the leftovers.[34] Termite mounds alone do not provide enough food for the aardvark, so they look for termites that are on the move. When these insects move, they can form columns 10–40 metres (33–131 ft) long and these tend to provide easy pickings with little effort exerted by the aardvark. These columns are more common in areas of livestock or other hoofed animals.[34] The trampled grass and dung attract termites from the Odontotermes, Microtermes, and Pseudacanthotermes genera.[34]

On a nightly basis they tend to be more active during the first portion of night (roughly the four hours between 8:00 p.m. and 12:00 a.m.); however, they do not seem to prefer bright or dark nights over the other. During adverse weather or if disturbed they will retreat to their burrow systems. They cover between 2 and 5 kilometres (1.2 and 3.1 mi) per night; however, some studies have shown that they may traverse as far as 30 kilometres (19 mi) in a night.[5]

Aardvarks shift their circadian rhythms to more diurnal activity patterns in response to a reduced food supply. This survival tactic may signify an increased risk of imminent mortality.[35]

Vocalisation

The aardvark is a rather quiet animal. However, it does make soft grunting sounds as it forages and loud grunts as it makes for its tunnel entrance.[32] It makes a bleating sound if frightened.[33] When it is threatened it will make for one of its burrows. If one is not close it will dig a new one rapidly. This new one will be short and require the aardvark to back out when the coast is clear.[33]

Movement

The aardvark is known to be a good swimmer and has been witnessed successfully swimming in strong currents.[33] It can dig a yard of tunnel in about five minutes,[32] but otherwise moves fairly slowly.

When leaving the burrow at night, they pause at the entrance for about ten minutes, sniffing and listening. After this period of watchfulness, it will bound out and within seconds it will be 10 metres (33 ft) away. It will then pause, prick its ears, twisting its head to listen, then jump and move off to start foraging.[32]

Aside from digging out ants and termites, the aardvark also excavates burrows in which to live, which generally fall into one of three categories: burrows made while foraging, refuge and resting location, and permanent homes.[5] Temporary sites are scattered around the home range and are used as refuges, while the main burrow is also used for breeding. Main burrows can be deep and extensive, have several entrances and can be as long as 13 metres (43 ft).[5] These burrows can be large enough for a person to enter.[6] The aardvark changes the layout of its home burrow regularly, and periodically moves on and makes a new one. The old burrows are an important part of the African wildlife scene. As they are vacated, then they are inhabited by smaller animals like the African wild dog, ant-eating chat, Nycteris thebaica and warthogs.[33] Other animals that use them are hares, mongooses, hyenas, owls, pythons, and lizards. Without these refuges many animals would die during wildfire season.[33] Only mothers and young share burrows; however, the aardvark is known to live in small family groups or as a solitary creature.[6] If attacked in the tunnel, it will escape by digging out of the tunnel thereby placing the fresh fill between it and its predator, or if it decides to fight it will roll onto its back, and attack with its claws.[6] The aardvark has been known to sleep in a recently excavated ant nest, which also serves as protection from its predators.[36]

Reproduction

Aardvark mother and young

Aardvarks pair only during the breeding season; after a gestation period of seven months,[5] one cub weighing around 1.7–1.9 kilograms (3.7–4.2 lb)[16] is born during May–July.[6] When born, the young has flaccid ears and many wrinkles. When nursing, it will nurse off each teat in succession.[28] After two weeks, the folds of skin disappear and after three, the ears can be held upright.[28] After 5–6 weeks, body hair starts growing.[28] It is able to leave the burrow to accompany its mother after only two weeks and eats termites at 9 weeks,[28] and is weaned between three months[16] and 16 weeks.[5] At six months of age, it is able to dig its own burrows, but it will often remain with the mother until the next mating season,[5] and is sexually mature from approximately two years of age.[16]

Conservation

Aardvarks were thought to have declining numbers,[6] however, this is possibly because they are not readily seen.[1] There are no definitive counts because of their nocturnal and secretive habits; however, their numbers seem to be stable overall. They are not considered common anywhere in Africa, but due to their large range, they maintain sufficient numbers. There may be a slight decrease in numbers in eastern, northern, and western Africa. Southern African numbers are not decreasing. It has received an official designation from the IUCN as least concern.[1] However, they are a species in a precarious situation, as they are so dependent on such specific food; therefore if a problem arises with the abundance of termites, the species as a whole would be affected drastically.[5]

Recent research suggests that aardvarks may be particularly vulnerable to alterations in temperature caused by climate change. Droughts negatively impact the availability of termites and ants, which comprise the bulk of an aardvark's diet.[37] Nocturnal species faced with resource scarcity may increase their diurnal activity to spare the energy costs of staying warm at night, but this comes at the cost of withstanding high temperatures during the day. A study on aardvarks in the Kalahari Desert saw that five out of six aardvarks being studied perished following a drought.[38] Aardvarks that survive droughts can take long periods of time to regain health and optimal thermoregulatory physiology, reducing the reproductive potential of the species.

Aardvarks handle captivity well. The first zoo to have one was London Zoo in 1869, which had an animal from South Africa.[28]

F-111 Aardvark
F-14 Tomcat from VF-114 Aardvarks with the squadron mascot painted on the tail

In African folklore, the aardvark is much admired because of its diligent quest for food and its fearless response to soldier ants. Hausa magicians make a charm from the heart, skin, forehead, and nails of the aardvark, which they then proceed to pound together with the root of a certain tree. Wrapped in a piece of skin and worn on the chest, the charm is said to give the owner the ability to pass through walls or roofs at night. The charm is said to be used by burglars and those seeking to visit young girls without their parents' permission.[39] Also, some tribes, such as the Margbetu, Ayanda, and Logo,[5] will use aardvark teeth to make bracelets, which are regarded as good luck charms.[6] The meat, which has a resemblance to pork, is eaten in certain cultures.[5] In the mythology of the Dagbon people of Ghana, the aardvark is believed to possess superpowers.[40] The Dagombas believe this animal can transfigure into and interact with humans.

The ancient Egyptian god Set is usually depicted with the head of an unidentified animal, whose similarity to an aardvark has been noted in scholarship.[41]

The titular character and his families from Arthur, an animated television series for children based on a book series and produced by WGBH, shown in more than 180 countries, is an aardvark.[42] In the first book of the series, Arthur's Nose (1976), he has a long, aardvark-like nose,[43] but in later books, his face becomes more rounded.[44]

Otis the Aardvark was a puppet character used on Children's BBC programming.

An aardvark features as the antagonist in the cartoon The Ant and the Aardvark as well as in the Canadian animated series The Raccoons.

The supersonic fighter-bomber F-111/FB-111 was nicknamed the Aardvark because of its long nose resembling the animal. It also had similarities with its nocturnal missions flown at a very low level employing ordnance that could penetrate deep into the ground. In the US Navy, the squadron VF-114 was nicknamed the Aardvarks, flying F-4s and then F-14s. The squadron mascot was adapted from the animal in the comic strip B.C., which the F-4 was said to resemble.

Cerebus the Aardvark is a 300-issue comic book series by Dave Sim.

Footnotes

  1. ^ a b c d e Taylor, A.; Lehmann, T. (2015). "Orycteropus afer". IUCN Red List of Threatened Species. 2015: e.T41504A21286437. doi:10.2305/IUCN.UK.2015-2.RLTS.T41504A21286437.en. Retrieved 12 November 2021.
  2. ^ a b Hoiberg 2010, pp. 3–4
  3. ^ "Aardvark, n." Dictionary of South African English. Dictionary Unit for South African English, 2018. 26 February 2019.
  4. ^ a b Schlitter 2005, p. 86
  5. ^ a b c d e f g h i j k l m n o p q van Aarde 1984, pp. 466–467
  6. ^ a b c d e f g h i j k l m n Goodwin 1997, pp. 2–3
  7. ^ Merriam-Webster Online Dictionary 2010
  8. ^ "aardvark". Oxford English Dictionary (Online ed.). Oxford University Press. March 2018. Retrieved 24 May 2018. (Subscription or participating institution membership required.)
  9. ^ "aardvark". Dictionary of South African English. Dictionary Unit for South African English. 2018. Retrieved 25 February 2019.
  10. ^ a b Shoshani 2002, p. 618
  11. ^ a b c d e f Shoshani 2002, p. 619
  12. ^ a b African Wildlife Foundation 2013
  13. ^ a b c d e f g h Rahm 1990, pp. 453–454
  14. ^ Asher, Bennett & Lehmann 2009, p. 854
  15. ^ Rodriguez 2013, p. 6
  16. ^ a b c d e f g h i j k l m Rahm 1990, pp. 450–451
  17. ^ Shoshani 2002, p. 620
  18. ^ Cote S, Werdelin L, Seiffert ER, Barry JC (March 2007). "Additional material of the enigmatic Early Miocene mammal Kelba and its relationship to the order Ptolemaiida". Proc Natl Acad Sci USA. 104 (13): 5510–5. Bibcode:2007PNAS..104.5510C. doi:10.1073/pnas.0700441104. PMC 1838468. PMID 17372202.
  19. ^ Seiffert, Erik R (2007). "A new estimate of afrotherian phylogeny based on simultaneous analysis of genomic, morphological, and fossil evidence". BMC Evolutionary Biology. 7 (1): 224. Bibcode:2007BMCEE...7..224S. doi:10.1186/1471-2148-7-224. PMC 2248600. PMID 17999766.
  20. ^ Buckley, Michael (2013). "A Molecular Phylogeny of Plesiorycteropus Reassigns the Extinct Mammalian Order 'Bibymalagasia'". PLOS ONE. 8 (3): e59614. Bibcode:2013PLoSO...859614B. doi:10.1371/journal.pone.0059614. PMC 3608660. PMID 23555726.
  21. ^ Chisholm, Hugh, ed. (1911). "Aard-vark" . Encyclopædia Britannica. Vol. 1 (11th ed.). Cambridge University Press. p. 2.
  22. ^ a b c d e f g h i j Rahm 1990, p. 452
  23. ^ Legendre, Lucas J.; Botha-Brink, Jennifer (11 July 2018). "Digging the compromise: investigating the link between limb bone histology and fossoriality in the aardvark (Orycteropus afer)". PeerJ. 6: e5216. doi:10.7717/peerj.5216. PMC 6045922. PMID 30018860.
  24. ^ Haussmann, Natalie S.; Louw, Michelle A.; Lewis, Simone; Nicol, Keegan J. H.; van der Merwe, Stephni; le Roux, Peter C. (1 August 2018). "Ecosystem engineering through aardvark (Orycteropus afer) burrowing: Mechanisms and effects". Ecological Engineering. 118: 66–72. Bibcode:2018EcEng.118...66H. doi:10.1016/j.ecoleng.2018.04.022. hdl:2263/65084. S2CID 104179393.
  25. ^ Legendre, Lucas J.; Botha-Brink, Jennifer (11 July 2018). "Digging the compromise: investigating the link between limb bone histology and fossoriality in the aardvark ( Orycteropus afer )". PeerJ. 6: e5216. doi:10.7717/peerj.5216. ISSN 2167-8359. PMC 6045922. PMID 30018860.
  26. ^ "Aardvark Forelimb and Scapula - Wits University". www.wits.ac.za. Retrieved 29 September 2024.
  27. ^ Martin 1983, p. 377
  28. ^ a b c d e f g h i j k Rahm 1990, p. 458
  29. ^ Taylor & Skinner 2004, p. 106
  30. ^ Anon 2003
  31. ^ a b Anon 2013
  32. ^ a b c d e Rahm 1990, p. 455
  33. ^ a b c d e f g Rahm 1990, p. 456
  34. ^ a b c Rahm 1990, p. 457
  35. ^ Weyer, Nora Marie; Fuller, Andrea; Haw, Anna Jean; Meyer, Leith Carl Rodney; Mitchell, Duncan; Picker, Mike; Rey, Benjamin; Hetem, Robyn Sheila (2020). "Increased Diurnal Activity Is Indicative of Energy Deficit in a Nocturnal Mammal, the Aardvark". Frontiers in Physiology. 11: 637. Bibcode:2020FrPhs..11..637W. doi:10.3389/fphys.2020.00637. ISSN 1664-042X. PMC 7358442. PMID 32733261.
  36. ^ Anon 2013a
  37. ^ Melton, Derek A. (June 1976). "The biology of aardvark (Tubulidentata-Orycteropodidae)". Mammal Review. 6 (2): 75–88. doi:10.1111/j.1365-2907.1976.tb00204.x. ISSN 0305-1838.
  38. ^ Rey, Benjamin; Fuller, Andrea; Mitchell, Duncan; Meyer, Leith C. R.; Hetem, Robyn S. (31 July 2017). "Drought-induced starvation of aardvarks in the Kalahari: an indirect effect of climate change". Biology Letters. 13 (7): 20170301. doi:10.1098/rsbl.2017.0301. PMC 5543026. PMID 28724691.
  39. ^ Rebecca 2007
  40. ^ Blench, Roger. "Aardvarks go shopping: Dagomba concepts of living things".
  41. ^ te Velde 1997, p. 13
  42. ^ WGBH 2013
  43. ^ Arthur's Nose, Thriftbooks; accessed 2020.09.29.
  44. ^ Arthur's Eyes, Thriftbooks; accesses 2020.09.29.

References