by Ted Dewan
In medieval bestiaries, the European bison was known as the ‘bonnacon’ or ‘vilde kow’, which defended itself by spraying a jet of excrement over a distance of 80 yards.
Since the end of the last ice age, the bison’s only predators have been bears, wolves and humans. Many archaeologists now believe that it was hunting by early humans that made them form large herds.
The size of the herds means an amorous male has to stand out. Successful males have evolved bigger heads and more powerful front legs and shoulders, covered in darker woolly hair. Rutting males run full-tilt at one another and clash heads: the sound carries for three-quarters of a mile.
Without bison urine there would have been no prairie: it transformed the fertility of the soil. The more bison, the more grass, the more bison. The fragrant bison grass, used to flavour vodka, thrives on bison urine.
It was the railroad that started the slaughter. The workmen who built railways across the USA in the mid-nineteenth century needed meat for food. At the same time, the British army decided ‘buffalo’ leather made the best boots. Hunters were offered $2 a hide (called ‘robes’) or 25 cents for a tongue. A full-time bison-hunter like Wyatt Earp or ‘Buffalo Bill’ Cody could kill a hundred in an hour. Shooting bison for fun from moving trains became a popular pastime.
It was all over by 1890. Only 1 in 5 of the slaughtered bison were put to commercial use, the rest rotted on the ground. The total contribution of the fifty-year ‘buffalo trade’ to the US economy was $20 million, a paltry 28 cents per animal.
Specicide led to genocide. The indigenous tribes relied on bison for every aspect of their livelihood. The US government encouraged the systematic extermination of the herd as the simplest way of ethnically cleansing the valuable prairie lands.
Today, the North American herd has recovered to 350,000. Most are photographed by tourists or farmed for food. With a third more protein and 90 per cent less fat, bison meat is more nutritious than beef. Cattle and bison hybrids are also bred for eating: they are called ‘cattalo’ and ‘beefalo’.
Box Jellyfish
The stomach with twenty-four eyes
Despite appearing to be just a mouth surrounded by tentacles, box jellyfish or cubozoans (literally ‘cubed animals’) have eyes with lenses, corneas and retinas very similar to our own. Odder still, despite having all this sophisticated equipment, their eyes are permanently out of focus.
This is because a box jelly doesn’t have a brain, just a ring of nerves around its mouth. Without central processing power, the blurry vision tells it all it needs to know. How big? Can I eat it? Will it eat me?
The eyes are on four club-like stems on each side of the cube-shaped body. As well as two ‘smart’ eyes, these stems each have four light-sensitive pits. Again, this is linked to their lack of a brain, which could integrate sensory information. For box jellies, ‘seeing’ a predator and knowing whether it’s day or night are separate tasks which require separate sense organs.
Their eyes differentiate them from the rest of the true jellyfish clan (the scyphozoans, from the Greek skyphos, cup) from which they split at a very early stage, over 550 million years ago.
Box jellies go to bed at 3 p.m. and get up at dawn. Once darkness begins to fall they lie motionless on the ocean floor, apparently ‘sleeping’.
Sight, however blurred, helps them in other ways. Unlike true jellyfish, which limply float waiting for food to swim towards them, box jellies can swim at speed (6 feet per second in some species) and steer around obstacles. This means they are able to ‘hunt’ prey. There is also evidence that they form mating pairs, with the male using his tentacles to impregnate the female, rather than just spraying eggs and sperm into the sea.
This also helps to explain their other major adaptation. Box jellies are fantastically venomous. One species, the sea wasp (Chironex fleckeri), is probably the most poisonous creature on earth. Its sting produces instant excruciating pain accompanied by an intense burning sensation. The venom attacks the nervous system, heart and skin, and death can occur within three minutes. Up to 10,000 people worldwide are stung each year, and there are regular fatalities.
STING CELL TECHNOLOGY
Another species, Carukia barnesi, is almost as toxic. Virtually invisible in water, being transparent and no bigger than a peanut, it is completely covered in stinging cells. Those who survive its sting may suffer ‘Irukandji syndrome’, experiencing intense pain, nausea, vomiting, catastrophically high blood pressure and a feeling of impending doom. It is named after an Aboriginal tribe whose folklore tells of a terrible illness that struck people who went swimming in the sea. The venom causes a massive release of the fight-or-flight hormone noradrenalin, so victims often ‘panic’ to death.
Why are box jellyfish so toxic and how is this linked to sight? It’s a question of scale. Because they can see, they tend to eat things larger than themselves. In order to minimise damage to their own rather delicate tentacles, they need to paralyse their prey immediately. They are only fatal to us because we are so large we blunder into them, exposing ourselves to far more of their sting cells than they usually need to kill their prey.
Butterfly
Souped-up moth
Butterflies and moths are the most numerous insect family after beetles, with 200,000 known species. Although butterflies are the more popular, carrying with them associations of sunshine and summer idleness, it’s the moths who make up 80 per cent of the Lepidoptera (‘scale-wings’). One of the reasons for this is temperature: butterflies are basically high-performance sex machines fuelled by flower nectar, Formula One cars to the moth’s family saloon. If a butterfly’s body temperature falls below 30°C it can’t fly and will either die or fall into a torpor. That’s why northern countries like Britain are relatively poor in butterfly species – there are only fifty-nine natives and some of them, like the Red Admiral and the Painted Lady, migrate annually, all the way from the Mediterranean. In comparison, continental Europe has over 400 species of butterfly, and tropical Costa Rica (which is the size of Wales) has 560.
Moths are much hardier, and are usually nocturnal. Their bodies are designed to conserve heat rather than absorb it, so they tend to have fatter, fur-covered bodies and rest with their wings spread to the side, rather than folded together above their backs like butterflies. Another point of difference is the antennae: butterflies have a smooth antenna rod with knobs at the end; moths’ are feathery. Again, this is partly to do with the day/night split. Moths are much less dependent on sight: they use their antennae as spatial orientation sensors, like our inner ears, to steady themselves as they fly and hover. Cut a moth’s antennae off and it will immediately collide with walls and crash to the ground.
Sight is important to butterflies but not quite in the way we imagine. Despite their beautiful appearance, butterflies are extremely near-sighted and cannot judge distance. This is an evolutionary trade-off: their vision may not be sharp, but they can see almost the full 360 degrees, both vertically and horizontally, which is handy for evading predators. The bold wing patterns have more to do with scaring off hungry birds than attracting mates. What really gets a female butterfly going is the male’s iridescent wing scales. These, arranged into the characteristic ‘eye-spot’ patterns, are ridged to reflect UV light – as he flutters his wings at close range he creates a UV strobe effect. Accompanied by heady gusts of pheromone, this literally mesmerises the female.
Unlike most animals, none of the words for ‘butterfly’ in European languages resemble one another: it is schmetterling in German; papillon in French; mariposa in Spanish; farfalla in Italian; borboleta in Portuguese and vlinder in Dutch.
Moths, for obvious reasons, tend to rely more on smell and hearing: a moth can sniff a potential mate 7 miles way. Moths’ ears are simple but effective; some species of tiger moth can even tune them to pick up the ultrasonic hunting call of bats and use their wing beats to create a jamming frequency. Both groups have scent scales, which release pheromones to at
tract females and help their own species recognise them. The Common blue butterfly smells strongly of chocolate; the Goat moth smells of goats.
SILKEN SECRET
Many species of moth feed on the tears of larger animals. Tears are a surprisingly nutritious broth of water, salt and protein – like our sweat, which butterflies like to lick. Some, like Mabra elantophila, are tiny and hardly trouble the elephants they steal from; others, like Hemiceratoides hieroglyphica from Madagascar, are large and sneaky: they have harpoon-shaped proboscises covered with hooks and barbs which they insert under a bird’s eyelids as it sleeps.
Cane Toad
Alien invasion
On 18 August 1935, 102 cane toads arrived in Australia from Hawaii. The toads were released on to the sugar cane plantations of northern Queensland to control the ravages of the cane beetle.
Seventy years later, there are now a hundred million cane toads in Australia. They have spread into an area bigger than Britain, France and Spain put together and the front line of their territory expands at a rate of 35 miles per year.
Given the catastrophic decline of the world’s amphibious species (see Frog), this may sound like good news. But cane toads aren’t good news. They are a catastrophic example of what can happen when humans try to manipulate nature.
Cane toads may yet prove useful: their tadpoles inhibit the growth of mosquito larvae and the venom contains serotonin, which can be used to treat heart disease, cancer, mental illness and allergies.
Bufo marinus is very poisonous. Swallowing them as eggs, tadpoles or adults leads to near instant heart failure for most animals. Australian museums display snakes that died so quickly the toad is still in their mouths. Native cats, or quolls, used to eating home-grown frogs, are threatened with extinction. Cane toads can even take out large crocodiles. Their venom is so strong that pet dogs become ill just by drinking water from bowls they have walked through.
In their home territories of Central and South America, cane toad populations are held in check by a combination of competition, disease and predators. In Australia there aren’t any other toads, few predators and lots of new things to eat. It’s virgin territory and they have risen to the challenge.
They produce four times as many eggs as native Australian frog species, and their tadpoles not only mature more rapidly, but – being poisonous – don’t get eaten. Juveniles and adults will consume anything, from other frogs to unguarded bowls of dog food. The more they eat the bigger they get: some have been recorded at 6 lb – the size of a small dog.
Even more worryingly, their new home seems to be changing them. Their legs are now 25 per cent longer than they were in the 1930s and they can travel five times faster, waiting until the evening to use man-made roads and highways rather than scrabbling through the bush.
Action to control the spread of the toads is widespread, particularly along the border of Western Australia, where the invasion is expected in early 2008. Anti-toad measures once involved driving around so as to run them over in cars. Although cruel hands-on methods like ‘cane toad golf’ still have their advocates, the most effective control is through nocturnal ‘toadbuster’ squads which raid the waterholes where they gather. A good week’s haul might top 40,000 toads. They are then either gassed or deep-frozen to death, and turned into liquid fertiliser called ToadJus.
A biological solution to the plague – genetically engineering a disease to render them sterile – is opposed by many environmental scientists, not least because it was that kind of thinking which caused the problem in the first place.
Despite its undeniable environmental impact, the cane toad has not yet caused any extinctions. Some birds and rodents have even learnt to flip them over and eat them by avoiding the poison glands. Many other species have grown to tolerate them, not least the sugar cane beetle, whose Australian population is, if anything, higher than it was in 1935.
Capercaillie
The fatuous grouse
Capercaillies, also spelt ‘capercailzies’, are huge woodgrouse as big as turkeys. The name is Gaelic for ‘forest horse’ – although there are no capercaillies (just as there are no snakes or moles) in Ireland. The Royal Society for the Protection of Birds gives the collective noun for capercaillies as a ‘tok’. Interestingly, however, tok is not a word in Gaelic, Danish, Norwegian or Finnish – the local languages of some of the places where these birds are found nor, according to the Oxford English Dictionary, is it a word in English either. (Tok is, however, the spelling of ‘talk’ in pidgin English and a first name in Chinese. It’s also a town in Alaska: pronounced toke, it means ‘peaceful crossing’ in Athabascan Indian. But we digress.)
Despite a valiant rearguard action by the RSPB, the capercaillie heads the list of British birds likely to go extinct by 2015. If it does, it will be the only British bird to have managed the feat twice.
The call of the male capercaillie imitates the sound of dripping water in early spring. It starts off with a similar pelip-pelip sound and then picks up speed with plip-plip-plip-itit-t-t, ending with -klop!, which sounds like a cork being pulled out of a bottle. The much smaller and less flamboyant females content themselves with a pheasant-like clucking noise. Male capercaillies perform a bizarre courtship ritual called a lek (from an Old Norse word meaning ‘to dance’) and they do this at so-called lekking sites. This involves strutting about with tails fanned out and wings held down, making an extraordinary series of noises including strangled gurgling, asthmatic wheezing and, of course, cork-popping. Some experts believe that there are also other sounds, below the range of human hearing, which carry for many miles, broadcasting the male’s splendour to distant females. When the eager females arrive, crouching and making enticing begging noises, spectacular fights break out between the males, resulting in injury or even death. Those males whose grandiose exertions fail to find them a partner can become extremely frustrated and will perform their absurd antics to anything that moves, even cars.
LEK LOUTS ON THE LASH
Capercaillies became extinct in Britain around 1785, owing to over-hunting and forest clearances. In the 1830s, a few birds were imported from Sweden, and by 1960 there were 20,000 of them in Scotland. Today there are only about a thousand: the population has halved in the last five years and the bird is in danger of becoming extinct again. About a third of the deaths are due to the ponderous, low-flying creatures colliding with deer fences and a few of them, no doubt, from giving the come-on to moving hatchbacks.
The longest recorded lifespan of a capercaillie is 9.3 years. A 1992 study of deviant capercaillies in Finland found that about 1 per cent of males behaved abnormally due to testosterone levels up to five times higher than the average. This may be because capercaillies live almost exclusively on a diet of blueberries, a fruit that is supposed to increase the libido and cure erectile dysfunction in humans. Addled by blueberry-fuelled lust, Finnish capercaillies displayed to humans, attacked stuffed male capercaillies and copulated with stuffed females. In 1950, there were three times as many capercaillies in Finland as there are today. This may be because so many of them are stuffed for scientific purposes.
Cat
Cuddly killer
What is a cat? Every child knows. Yet cats, among the most familiar of animals, are ineffably mysterious. What are they for? What do they want? Cats spend 85 per cent of their day doing absolutely nothing. Eating, drinking, killing, crapping and mating take up just 4 per cent of their life. The other 10 per cent is used to get around. Otherwise they are asleep, or just sitting. They say cats were the last animals to be domesticated, by the ancient Egyptians around 3,500 years ago. But it is cats that have domesticated us, in their own time, for their own reasons. Today, only a quarter of American cat ‘owners’ say they deliberately went out to acquire a cat; in 75 per cent of cases, it was the cat that acquired them. And studies have shown that many more people claim to own a cat than there are cats. When your cat disappears for a while it is not, in fact, off on a hunting expedition, it is
next door but one having another free meal or asleep on the window-sill with one or another of its many doting ‘owners’. Cats need to eat the equivalent of five mice a day. A cat given unlimited access to food will only eat a mouse-sized portion at a single meal. Is your cat eating five meals a day? Of course not: it’s dining out elsewhere, later.
Most cats carry a parasite thought to have long-term, irreversible effects on the human brain. Toxoplasma gondii may turn men into grumpy, badly dressed loners and women into promiscuous, fun-loving sex kittens. Half the British population are already infected …
One of the big selling points of cats is that they are clean animals that carefully cover up their own faeces. Except they don’t always – they only do it about half the time. They leave piles of the stuff all round the edges of their territory as a kind of malodorous ‘Keep Out’ sign. The polite word for this is ‘scats’. Milk, cat food and central heating are all bad for cats. Milk gives them diarrhoea, cat food rots their gums and central heating causes them to moult all year round. Then they lick off and swallow their fur, which clogs up their digestive system.
There are about 75 million cats in the USA, which are responsible for the deaths of a billion birds and five billion rodents every year. Right up until the seventeeth century it amused people to stuff wicker effigies of the Pope with live cats and then burn the lot. This produced sound effects that pleased Puritans but not cats: they have exceptionally sensitive hearing and can even hear bats.
