The Book of Animal Ignorance (2 page)

Aardvark

Ancient, odd and out on its own

A
ardvarks are the last survivors of a primitive group of mammals that have lived in Africa since the dinosaurs. They were originally classified alongside anteaters and armadillos in the order
Edentata
(‘no teeth'), but they are not remotely related, having evolved on different land masses.

In fact, aardvarks don't have any close relatives: they are the only mammal species that boasts an entire order to itself.
Tubulidentata
means ‘tube-toothed' and aardvark teeth are completely different from those of any other animal. They are twenty flat-topped pegs, made up of hexagonal tubes, right at the back of their mouths. Instead of enamel, they are are covered with
cementum
, the stuff that is normally inside teeth. Like rodents' teeth, they never stop growing.

The aardvark has a primitive ‘designed by committee' look to it: the nose of an anteater, the ears of a donkey, the feet of a rabbit and the tail of a giant rat. But don't be fooled: it has outlasted many other species because it does one thing supremely well. It is a termite-eating machine.

As soon as darkness falls it leaves its burrow and applies its snout to the ground, snuffling in huge zigzags across the savannah in search of mounds to crack open and lick clean. It can cover 30 miles and hoover up over 10 pints of termites in a single evening. The aardvark nose contains more bones and scent receptors than that of any other mammal. Its ears can pick up the tiniest of underground movements and its powerful claws tear open mounds that would blunt a pickaxe. Aardvarks are strong: they can grow to the size of a rugby forward and dig a burrow faster than six men using shovels.
Their thick skin protects them from termite bites and as the long, sticky tongue reels in supper, they can close their nostrils at will, to stop the insects running up inside.

They have also built up a remarkably beneficial relationship with a plant known as the ‘aardvark cucumber' that grows its fruits underground. Aardvarks dig them up and eat them when water is scarce, then bury their seed-laden droppings, ensuring the plants' survival. The
San
(bushmen) of the Kalahari call the fruit ‘aardvark dung'.

Humans and hyenas are the only predators that will attack a fighting-fit aardvark. Despite its solitary, reclusive nature, a cornered aardvark is a formidable foe, slashing with its claws, kicking its legs, and executing high-speed forward somersaults.

TERMITE TAKEAWAY

Aardvarks are hunted for meat and leather:
aardvark
is Afrikaans for ‘earth pig' and they are said to taste like gamey pork. They are also called ‘ant bears' but their Latin name,
Orycteropus afer
, means ‘African digger-foot'. The bushmen believe that aardvarks have supernatural powers because they are literally ‘in touch' with the underworld.

This elusive nocturnal animal probably only became known in the English-speaking world because it is so close to the start of the dictionary. It very nearly didn't make it.
Aardvark
, the fourth noun listed in the 1928
Oxford English
Dictionary
, owes its inclusion to the editor James Murray, who overrode his assistant's opinion that the word was ‘too technical'.

Albatross

Flying non-stop for a decade

T
here are twenty species of albatross from the gull-sized Sooty to the vast Wandering albatross (
Diomedes exulans
, or ‘albatross in exile'), with its record 11-foot wingspan. They fly further and for longer than any other family of birds. Satellite tracking reveals that some albatrosses fly around the entire planet in less than two months and can soar for six days without flapping their wings. Rather than soaring high up in the thermals like birds of prey, they keep close to the surface of the sea, using the lift generated by wind from waves. The most energetic part of any albatross flight is take-off: it is the only time the bird needs to flap its wings vigorously.

As soon as a young Wandering albatross gets airborne it won't land again until it is ready to breed, which can be ten years later. They feed on fish, squid and krill, either diving into the sea or picking it off the surface, and sleep on the wing, with each half of the brain taking it in turns to turn off.

Albatrosses belong to the order
Procellariiformes
, originally
Tubinares
, which means ‘tube-nosed'. These tubes run the length of their large, hooked beaks and lead to very well-developed scent organs, allowing them to detect their food and nesting sites from many miles away. In some species the tubes have a dual function, allowing them to breathe from one part, while sneezing excess sea salt from another.

Young albatrosses spend several years watching their elders to learn the elaborate beak-clacking courtship dances. When they find a partner, they mate for life, developing a unique body language which they use to greet each other after long separations. They raise only one egg every two years, with the parents taking turns to sit on the
nest or go off in search of food. An albatross will regularly fly 1,000 miles for a single mouthful for its chick. Solid food is regurgitated, but for longer journeys it can also be broken down into a concentrated protein-rich oil, kept in their stomachs. This can be used in place of water to quench their thirst, or regurgitated as a nutritious fish smoothie for the chick.

Albatrosses can live for sixty years but breed so slowly that they are at risk of extinction within the next century. The main threat is long-line fishing. Over 100,000 die each year caught in the millions of baited hooks that are used to catch tuna.

Samuel Taylor Coleridge's poem ‘The Rime of the Ancient Mariner' (1798) practically invented the myth that killing an albatross brought bad luck. In fact, British sailors regularly killed and ate them, making pipes from their bones and purses from their feet. A more widespread belief was that the albatross was the reincarnated spirit of a drowned sailor. Some Scottish fishermen still don't like using Swan Vesta matches because the bird on the box looks like an albatross.

When Portuguese explorers first saw them they called them
alcatraz
, their name for any large seabird. The word originally came from the Arabic
al-
gatt
ā
s
, the leather bucket on a waterwheel which resembled a pelican's bill. So, in Portuguese, the Birdman of Alcatraz literally means the ‘Birdman of the Large Seabird'.

Anglerfish

Worse things happen at sea

S
urely a life doesn't get any bleaker than that of the deep-sea anglerfish? Two miles down in the endless darkness, a gloomy motionless lump of brittle bone, atrophied muscle and paper-thin black skin with only luminous bacteria for company. A life spent doing nothing except waiting, often for months at a time, turning your light on and off in the hope that it will attract some other creature out of the inky gloom long enough for them to stray too close to your cavernous mouth …

The name ‘anglerfish' is used for about 300 species – including sea toads, frogfish, batfish and monkfish – which attract their prey with a long, flexible appendage like a fishing rod, typically growing out of the middle of their heads. At the end of it, in place of a dangling maggot, there is the
esca
(Latin for food), which can be wiggled to mimic live bait. In the deep-sea anglers, the esca lights up, thanks to a chemical process controlled by the bacteria that live on it. In return for light, the anglerfish supplies them with food. Different anglerfish have differently shaped escas. It was once thought this was to attract different prey, but it's now believed that they all have a similar diet. Perhaps having a big, bendy, glowing rod sticking out of your head is a form of sexual display.

The deep-sea anglers are some of the most ugly and outlandish creatures on the planet. They have an elastic stomach that can swallow prey twice as large as themselves (it even has a light-proof lining in case they swallow luminous fish). To prevent their prey escaping they have backwards-facing teeth in their mouths and another set of teeth in their throats. The female Illuminated netdevil (
Linophryne arborifer
) looks like a
fluorescent root vegetable, with a black bulbous body and two shimmering lures streaming off like psychedelic foliage. Her Latin name means ‘tree-shaped toad that fishes with a net.' The Hairy seadevil's (
Caulophryne polynema
) huge spiny fins have a decayed look, its body is covered in unpleasant pale hairs and its lure looks like a frayed stick of liquorice. It has one of the most sensitive lateral lines of any fish – the tiniest movement triggers the opening and closing of its jaws. Elsman's whipnose (
Gigantactis elsmani
) swims along upside down, trailing its lure along the seabed. The Wolftrap seadevil (
Lasiognathus saccostoma
, or ‘hairy-jawed sack-mouth') has a lure with three shining hooks on the end that it casts forwards like a fly-fisherman. Prince Axel's wonderfish (
Thaumatichthys axeli
) has its lures hanging down from the roof of its mouth like a pair of fluorescent tonsils.

The male deep-sea anglerfish is much smaller than the female and doesn't have a lure. He's interested in mating, not fishing. He uses his giant eyes to look for a suitable female, and his enormous nostrils to sniff out her pheromones. Having found her, he latches on to her with his teeth and then starts to disappear. Scales, bones, blood vessels all merge into those of the female. After a few weeks all that's left of the male are the testes hanging off the female's side, supplying her with sperm. Females have been found with eight testes attached to their sides.

LOVE IN THE DARK

In some species, if the male fails to find a female, then he will eventually turn into one himself and grow massively in size. As the anglerfish themselves are wont to remark: there's only one thing worse than being an anglerfish and that's being a
male
anglerfish.