The Aardwolf
It looks like a miniature striped hyena, but it's not. The aardwolf (the name means "earth-wolf" in Afrikaans) is so highly adapted to eating termites that all its teeth, except for its canines, have dwindled to mere pegs. Its canines are still well-developed, and aardwolves use them to defend their territory from other aardwolves.
Aardwolves live mostly on termites. Their favorite kind is termites of the genus Trinervitermes, and they don't live where there are no Trinervitermes termites. They are the only African mammals that can tolerate the poisonous secretions of these termites, so other species don't compete with them for food.
In some places, Trinervitermes stay in their nests and don't go out during the colder seasons, so the aardwolves living there will switch to Hodotermes termites at these times.
An aardwolf doesn't have powerful claws or forelegs like an anteater or aardvark, so it can't dig out the termites. Fortunately, it doesn't have to. The Trinervitermes termites come out of their nests in groups of thousands of workers and soldiers at night, to crawl on the ground eating and collecting grass. The aardwolf can simply walk up to such a party and begin licking them off the ground; it can lick up 30,000 termites in one night. Trinervitermes termites, especially T. bettionianus, "stands out as the only species which regularly forages completely exposed on the surface in large, concentrated parties" (Kruuk and Sands 1972, see the paper's full title below). The aardwolf seems to use its keen hearing to detect the termite parties, more than smell or vision.
It's often stated that aardwolves never eat meat or threaten livestock. This is nearly always true, but an incident in South Africa shows that it isn't always. In 2012, an aardwolf slipped into a pen with two captive geese, and killed and partly ate one. It ate the softer abdomen and inner legs of the first goose. It was in the process of killing the other goose by enveloping the bird's head in its mouth when a warden interrupted and photographed it. This was in winter, when aardwolves in this area often go hungry and can lose up to one-fifth of their body weight.
Aardwolves live in burrows in the earth, and come out only at night.
An aardwolf can raise the mane of black hair on its back when frightened or angry to look much larger, and can even roar to frighten off an attacker.
Because they eat insects, aardwolves have evolved a social structure that's very different from other hyenas. Their food doesn't have to be brought down by a pack, and it cannot be shared, so aardwolves have never evolved the clan system of spotted hyenas. Yet, they don't have the clan structure of brown and striped hyenas, either. Instead, aardwolves are more or less monogamous, with one male and one female having a permanent relationship. The female may sneak off to mate with a more attractive male, then return to her mate. If she's too blatant about her unfaithfulness, however, she risks the male's abandoning her and her cubs.
Scientists once thought that the ancestors of aardwolves must have separated from other hyenas a very long time ago, because of their unique anatomy. However, a recent study of hyaenid genetics suggests that the aardwolf lineage is more recent -- only 10.6 million years old.
- Kruuk H, Sands WA. The aardwolf (Proteles cristatm Sparrman) 1783 as predator of termites*. African Journal of Ecology. 1972 Nov 1;10(3):211-27. (What are these strange numbers and letters?)
(Excellent paper with a lot of detail on Trinervitermes and aardwolf behavior -- plus, you learn why wildlife biologists spend so much time picking through animal dung.)
- Matsebula SN, Monadjem A, Roques KG, Garcelon DK. The diet of the aardwolf, Proteles cristatus at Malolotja Nature Reserve, western Swaziland. African Journal of Ecology. 2009 Sep 1;47(3):448-51.
- Richardson PR. Aardwolf: the most specialized myrmecophagous mammal. South African Journal of Science. 1987 Oct 1;83(10):643-6.
- Yarnell, RW, MacTavish, L. A novel record of aardwolf Proteles cristata feeding behaviour. Transactions of the Royal Society of South Africa. 2013 Jan 11;68(1): 81-82. (Link is to a pre-publication version of the paper, without the authors' names.)
(Last link check May 5, 2022.)

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