Mammals
Aardvark
Orycteropus afer · also called antbear, earth pig, Cape anteater
The aardvark is one of the strangest mammals in Africa — a nocturnal, pig-snouted, rabbit-eared digging machine that lives on ants and termites, builds burrows the whole savanna depends on, and belongs to a branch of the mammal family tree with no other living members.
Overview
Aardvarks are found across almost all of sub-Saharan Africa, in savanna, grassland, open woodland, and bush — anywhere with a good supply of ants and termites and soil soft enough to dig. They avoid only true desert and closed rainforest. They are strictly nocturnal and solitary, spending the day in a burrow and emerging after dark to forage over several kilometres. Despite being common and widespread, they are rarely seen even by people who live alongside them.
Built to dig and to feed
- Claws. The front feet carry four flattened, spade-like nails driven by heavy shoulder muscles; an aardvark can excavate a metre into packed earth in seconds, faster than a team of people with shovels.
- The snout and tongue. A long, mobile pig-like snout with an extraordinary sense of smell locates nests; a thin, sticky 30 cm tongue then extracts the insects.
- Sealable nostrils and dense bristles keep dirt and biting insects out while it digs and feeds.
- Tube teeth. Its only teeth are peg-like cheek teeth made of many tiny tubes fused together — the feature that names its order, Tubulidentata. It has no incisors or canines and does not chew its prey.
An order of one
The aardvark is the sole survivor of an entire mammalian order. Its closest kin, genetically, are elephants and manatees within the ancient African group Afrotheria, but its own line has been distinct for a very long time and every other tube-toothed animal is extinct. Everything about it — the anteater-like tongue, the pig-like snout, the armadillo-like claws — evolved independently of the animals it superficially resembles.
The savanna’s landlord
Because an aardvark digs constantly and moves on, it litters the landscape with abandoned burrows, and an enormous range of other animals move into them: warthogs, hyenas, porcupines, foxes, mongooses, hares, snakes, monitor lizards, owls, and — importantly for conservation — African wild dogs, which frequently raise their pups in old aardvark holes. This makes the aardvark a keystone species across much of Africa.
Reproduction
A female gives birth to a single, hairless cub in a burrow after a seven-month pregnancy. The cub stays underground for about two weeks, then begins accompanying its mother on foraging trips, and digs its own burrow at around six months.
Status
The aardvark is Least Concern, but its dependence on ants and termites makes it vulnerable to drought: in dry years those insects collapse, and aardvarks have been recorded starving and declining in arid regions such as the Kalahari. As severe droughts become more frequent, the health of aardvark populations — and of all the species that rely on their burrows — is an increasing concern.
Aardvark: common questions
What is an aardvark related to?
Almost nothing. The aardvark is the only living member of its entire order, Tubulidentata, and has no close relatives. Genetic work places it in a very ancient African group, the Afrotheria, alongside elephants, hyraxes, manatees, and elephant shrews — but its own lineage split off tens of millions of years ago, and every other tube-toothed species is long extinct. Its resemblance to pigs, anteaters, and armadillos is entirely convergent — different animals evolving similar bodies to do the same job, in this case digging up and eating social insects.
How does an aardvark eat ants and termites?
It finds nests and foraging columns by smell, using a long snout packed with more scent-detecting tissue than almost any other mammal. Then it tears the nest open with powerful, hoof-like claws and pushes in its long, thin, saliva-coated tongue, hoovering up the insects. It swallows them whole; a muscular stomach grinds them up, so the aardvark does not need chewing teeth at the front of its mouth. A single animal can consume tens of thousands of insects in one night's foraging.
Why are aardvark burrows so important?
An aardvark is a prolific digger and abandons burrows constantly, leaving a landscape dotted with ready-made shelters. Dozens of other species use them — warthogs, porcupines, bat-eared foxes, mongooses, hares, ground squirrels, snakes including pythons, monitor lizards, owls, and, significantly, endangered African wild dogs, which often den in old aardvark holes. In many African ecosystems the aardvark is a keystone species because of the homes it provides for everything else.
Are aardvarks endangered?
The species is listed as Least Concern and is still widespread across sub-Saharan Africa, though it is so nocturnal and secretive that population trends are hard to track. The clearest emerging threat is climate — aardvarks are sensitive to drought, because dry years crash the ant and termite populations they depend on, and studies in the Kalahari have recorded aardvarks starving and whole local populations declining during severe droughts, which are projected to become more frequent.