Aardvark

Quick Take

• The aardvark's closest living relative isn't the anteater or armadillo. It's an animal you'd never guess. Discover the surprising relative →
• Its teeth are built unlike any other mammal's on Earth, and the reason why reveals something strange about its ancient past. Explore their unique teeth →
• An aardvark can move two feet of soil in 15 seconds, and that remarkable feat is just the beginning of what makes it one of nature's most unlikely survivors. See the digging feats →
• Despite looking primitive, the aardvark has an evolutionary score that puts it above almost every other animal on the planet. Uncover their evolutionary status →

Because they spend the daytime hours hidden in their underground burrows, only emerging at night to hunt for food, aardvarks are rarely seen by people. In some regions, though, they are hunted by people for food and are becoming increasingly affected by expanding human populations as more of their natural habitats disappear to make way for growing settlements.

Origins and Evolution

The Aardvark (Orycteropus afer), also known as an antbear, is unique in terms of its evolutionary makeup. It has been assessed as having the highest score for evolutionary distinctiveness, according to the EDGE scientific method. This is because it does not have many close relatives and has been evolving independently for millions of years. The Aardvark is the sole surviving species of its order, Tubulidentata, and its closest relatives have been extinct since the late Pleistocene era (2 million to 10,000 years ago).

Through millions of years, species have split off and changed in various ways, providing proof of their common ancestor and showing that evolution is still at work. However, some species have remained virtually unchanged since their ancient origins and are referred to as living fossils. The aardvark is an intriguing example of this evolutionary phenomenon.

The aardvark’s unique physical attributes stem from its evolutionary background as an ancient species. The name of its order, Tubulidentata, alludes to one of its most peculiar features: its teeth. Unlike the teeth of most mammals, which consist of one main pulp cavity covered with a layer of dentin and enamel, an aardvark’s tooth is composed of hundreds of individual straw-like tubes held together by the same material that holds our teeth in place. Remarkably, these tubes are constantly being replaced and regrown; a single aardvark tooth can have up to 1,500 of these small channels.

Humans have developed more advanced teeth than the primitive 12 to 14 that aardvarks possess, yet aardvarks are still able to consume 50,000 ants and termites in one night with their sticky tongues. Similar to early mammals, they possess a proto-gizzard that helps to grind up their food as if they had teeth. Scientists have found that the aardvark’s genes are highly conserved, meaning they are much more similar to the DNA of early mammals than other species. This suggests that the aardvark has not evolved much since ancient times. Nature may sometimes revise its creations, but the aardvark is an example of something that cannot be improved.

Classification

Aardvarks are small pig-like mammals that are found inhabiting a wide range of different habitats throughout Africa, south of the Sahara. They are mostly solitary and spend their days sleeping in underground burrows to protect themselves from the heat of the African sun, emerging in the cooler evening to search for food. Their name originates from the Afrikaans language of South Africa and means “Earth Pig,” a reference to their long snout and pig-like body. Aardvarks are unique among animals in that they are the only surviving species in their order. Until recently, it was widely believed that they were most closely related to other insectivores, such as armadillos and pangolins. However, this is not the case, as their closest living relatives are thought to be elephants.

Anatomy and Appearance

Aardvarks have a unique appearance among mammals (and indeed all animals) as they display the physical characteristics of a number of different animal species. They have medium-sized, almost hairless bodies and long snouts that make them look distinctly pig-like at first, with thick skin that both protects them from the hot sun and also from being harmed by insect bites. They are able to close their nostrils to stop dust and insects from entering their nose. They have tubular, rabbit-like ears that can stand on end but can also be folded flat to prevent dirt from entering them when they are underground. Aardvarks have strong claws on each of their spade-like feet; combined with hind legs that are longer than their front legs, these features make them powerful diggers capable of excavating vast amounts of earth at an alarming rate. Because they spend most of their lives underground or hunting in the dark, they have poor eyesight but are able to easily navigate their surroundings using their excellent sense of smell to both find prey and sense potential danger.

Distribution and Habitat

Aardvarks are found in a wide variety of different habitats throughout sub-Saharan Africa, from dry deserts to moist rainforest regions. The only stipulation (other than having good access to plenty of food and water) is to have good soil in which they can dig their extensive burrows. Despite being highly skilled at digging in sandy or clay soil types, rockier regions prove more of a challenge to create their underground homes, so the aardvark will move to another area where soil conditions are better suited to digging. Their burrows can be up to 40 feet long in a home range that can be anywhere from one to two square miles. Their burrows often have multiple entrances, and aardvarks always exit head-first so they can identify potential predators using their keen sense of smell.

Behavior and Lifestyle

Aardvarks are mainly solitary animals that come together only to mate and are never found in large groups. They live in underground burrows to protect them both from the hot daytime sun and from predators. Aardvarks are nocturnal mammals, only leaving the safety of the burrow under the cover of night when they go in search of food and water, often traveling several miles in order to find the biggest termite mounds guided by their excellent hearing and sense of smell. Despite often having a large burrow comprised of an extensive network of tunnels, aardvarks are also known to be able to quickly excavate small temporary burrows where they can protect themselves quickly rather than having to return to their original dwelling.

Reproduction and Life Cycles

Aardvarks have specific mating seasons that occur every year. Depending on the region, young can be born either in October to November or in May to June. Female aardvarks, known to give birth most years, deliver a single offspring after a gestation period that usually lasts for around seven months. Newborn aardvarks often weigh as little as four pounds and are born with hairless, pink skin in the safety of their mother’s burrow. Baby aardvarks spend the first two weeks of their lives in the safety of the underground burrow before beginning to venture out with their mother under the cover of night. However, despite accompanying their mother in search of food, they aren’t weaned until they are around three months old. Young aardvarks live with their mother in her burrow until they are around six months old, when they move out to dig a burrow of their own. Although their lifespan in the wild is not entirely clear, aardvarks tend to live for more than 20 years in captivity.

Diet and Prey

The diet of aardvarks mainly consists of ants and termites, with termites being their preferred food source. Despite this, they are known to also eat other insects, such as beetles and insect larvae. Aardvarks are built to be insectivores with strong limbs and claws that are capable of breaking into the harder outer shell of termite mounds very efficiently. Once they have broken into the mound, they then use their long, sticky tongue to harvest the insects inside and eat them whole without chewing, as they are then ground down in their muscular stomachs. One of the aardvark’s most distinctive features is its columnar cheek teeth, which serve no functional purpose. For larger ant species that require chewing, they use the incisors located toward the back of their mouths. Aardvarks are also able to use the same techniques to break into underground ant nests.

Predators and Threats

Despite the fact that aardvarks are nocturnal animals that live in the safety of underground burrows, they are threatened by a number of different predators throughout their natural environment. Lions, leopards, hyenas, and large snakes (most notably pythons) are the main predators of aardvarks, but this does vary depending on where the aardvark lives. Their main form of defense is to escape very quickly underground. However, they are also known to be quite aggressive when threatened by these larger animals. Aardvarks use their strong, sharp claws to try to injure their attacker, along with kicking the threatening animal with their powerful back legs. Aardvarks are also threatened by humans who hunt them and destroy their natural habitats.

Interesting Facts and Features

Aardvarks use their long, sticky tongue to lap up to 50,000 insects a night from inside termite mounds or underground ant nests. Their worm-like tongues can actually grow up to 30 cm in length, meaning they can reach more termites further into the mound. Their love of insects has actually led to aardvarks being called Antbears. Aardvarks are also thought to get almost all the moisture they need from their prey, meaning they rarely need to drink water. Aardvarks are thought to be among the world’s most prolific diggers, with their strong limbs, claws, and shovel-like feet enabling them to shift two feet of soil in just 15 seconds.

Conservation Status and Life Today

Today, aardvarks are listed by the IUCN as a species that is of Least Concern. Despite the fact that population numbers of aardvarks have most certainly declined in some countries, in others, their numbers remain stable, and they are commonly found in both protected areas and regions with suitable habitats. They are increasingly threatened by habitat loss in the form of deforestation and expanding towns and villages. Due to their elusive nature, exact population sizes are not fully known.