What would your life have been like if you were born a few tens of thousands of years ago? Not easy. You would have lived around 35 years. As your body grew old, you could not depend on a regular and balanced food supply; you could not retreat behind cosy walls when the nights grew cold; you could not take medicine to combat illness, or go to the hospital to have broken bones mended. If famine struck, what little food there was would have to go to the strong and the children - at such times, to nurture ailing relatives could be suicide. If your lifestyle was nomadic, you would slow the group down; hungry predators would eye your weakening frame.

For many of us humans, that world is, happily, of the past. For almost all animals, however, it is the present. I saw a nature program once where a zebra was rolling around on the ground, scratching its back luxuriously. Some lions spotted its lack of alertness, and pounced; far too late, the zebra tried to struggle to its feet - the lions wrestled it down, throttled it, and began to tear into its corpse.

Nature is not kind; the life of animals consists mainly of trying to keep hunger and/or sexual failure at bay. Performing at peak level is difficult, often impossible; evolution is under constant pressure to develop easier ways for creatures to survive and reproduce. Evolution sometimes makes brilliant, qualitative changes - tactical leaps which cut corners around which previous generations have toiled. Creatures harness some unexpected property of their body or environment*, and life becomes easier.

* The body/environment dichotomy is less meaningful than one might think - see Dawkins, ' The Extended Phenotype '.

In many creatures, some of their characteristics evolve as a result of information contained in the minds of others. Here's the shortcut: even though you are not big or intimidating, you can appear so; even though you are dangerous, you can appear tempting. Into the former category fall the bluffers; into the latter, the tricksters.

Bluffers:
Most animals are afraid of some other creature. Many prey animals take advantage of this; if they can mimic the frightening animal, potential predators will think twice.

Animals which live in burrows quite often evolve the ability to hiss: hole-nesting birds are one of these. A bee hissing on its own is not an entirely convincing snake-mimic; so some bees, when alarmed, hiss in unison with their fellows - a bear may then think twice about taking the meal of honey. Bees themselves are frightening to some animals; it has been suggested that burying beetles imitate bumble-bee sounds in order to scare off predators.

Some animals are less specific in their scare-tactics. There is a species of frog which, when in the clutches of a predator, will make a sudden, intense cry that more often than not makes the predator drop it out of shock. When threatened, Texas horned lizards inflate; they also burst the walls between sinuses and eye sockets, squirting out jets of blood from their eyes. These alarming fountains can spurt out to more than a metre [John Downer, 'SuperNatural']. In the deeps of the sea, about 80 per cent of organisms emit light. But this environment is still almost entirely black. A sudden flash of light can frighten a predator; failing that, it may attract its enemies.

There are more subtle ploys around. Many moths, when hunted by bats, will make a sharp, ultrasonic sound; the bat, navigating by sound echoes, is disoriented by this sudden loud 'echo'; it thinks it's about to crash into something. At this moment of confusion, the insect makes good its escape.

Back in the deep ocean, down where the last vestiges of light penetrate, it is possible to see the shadows of animals above, blocking the faint rays of sun. Once again, bioluminescence comes into play: some fish and squid which live in this twilight region give out light which exactly cancels out the effect of the sun, rendering them invisible from below³.

Many creatures use visual bluffs, some of which are quite elaborate. Hawkmoths are a family of caterpillars; when threatened, one species can inflate one end of its body into a 'snake head', which it sways to and fro, making pretend strikes. Peacock butterflies combine strategies; when a bird threatens, the butterfly opens its wings, and exposes conspicuous eye spots; at the same time, it hisses like a snake.

Snakes are not the only animal which is mimicked; for example, spider mimicry is also common. There is a fly that lifts its abdomen when threatened, to make itself look like a hunting spider; the hairstreak butterfly has 'eye and antenna' markings on its wings.

Some feign death. When butterflies hear sound between 40 and 80khz, it is most likely to come from a hunting bat; they then choose whether to lie low or take flight. As the sound becomes more intense, a fleeing butterfly can do one of two things: increase its speed and zigzag, or pretend to be dead, falling to the ground like a leaf. Hog-nose snakes are 'two-sense bluffers'. When threatened, they writhe in their 'death throes'. Presumably in the hope that the predator's understanding of decomposition is limited, they also release scummy fluids that give off the smell of a rotting carcass. The West Indian wood snake "coats its scales with a fluid that stinks of decomposing flesh . . . special blood vessels in the eye burst to redden the eyes and cause blood to run from the gaping mouth". The opossum "falls on its side and lies perfectly still, eyes half open with its mouth in a rictus grimace . . . it also defecates and emits a foul-smelling green gunge from its anal glands" [John Downer, 'Supernatural'].

Of course, life's not all about eating. We must all attract mates. The purpose of birdsong (as anyone who has heard braying peacocks will know) is not to delight human ears; it is purely functional. One of the functions is to proclaim and defend a territory. Some male birds try to deceive their territorial rivals by moving around their territories and singing a variety of songs; this is designed to trick nearby males into thinking that there is more than one territory-holder singing.

"Migrating birds can become confused by the apparent inversion of the night sky caused by city lights and, as a result, may crash-land into high-rise buildings . . . In Toronto, . . . city gulls harry . . . birds towards the glowing buildings. These town pirates have learned the routes through the maze of lights and reflective glass and manoeuvre expertly through the dangers. The birds began their marauding lives by feeding on the casualties, but in time they learned their own ways of increasing the death toll" ['SuperNatural'].

Let's give Jeffrey Dahmer a cloak of invisibility:
Have you seen 'The Silence of the Lambs'? Remember the end sequence where the deranged baddie* kills the lights, whips on his infrared glasses, and proceeds to track down a hapless Jodie Foster? Red dragonfish do pretty much the same thing. They live deeper than light can penetrate. Other fish which live at the same depths can see a lot of their predators in time, because many animals down there give out blue light while hunting. But none of them can see red, except for the dragonfish, which searches the blackness with its red beam. It's as if while you were taking a nighttime stroll, a huge murderous bat was hunting you by echolocation.

* I love the enthusiasm which drives people to carry out these obscure but fascinating tasks. This sound comes courtesy of the New Mexico Museum of Natural History and Science.

Some marine creatures are exposed to a sound so loud that it knocks them out or even kills them. These 'sound lasers' are emitted by dolphins, and perhaps by sperm whales. They use the 'melon' structure on their head to focus and shoot out a narrow beam of sound which stuns or kills their prey (for dolphins, the prey is fish; for the deep-diving sperm whale, it is squid). It has been suggested that the high-intensity sounds cause their prey's swim bladder (an organ which helps fish to control their depth, and from which lungs may have evolved) to resonate, disorienting the animal by causing its body tissues to vibrate¹. Fascinatingly, dolphins have developed - of necessity - an echolocation and sound laser etiquette; without this, they would be constantly stunning or confusing each other.

 ¹ John Downer, "SuperNatural"

The archer fish is a deadly little animal. It has a funnel in its mouth that acts as a barrel for shooting out water at high velocities. It positions itself near the surface of the water, underneath any insect which is on a twig above; it fires at the insect with great accuracy, compensating for the change in direction of light (and therefore in the apparent position of the unsuspecting insect) as it passes from air to water. If there are other archer fish around, they all leap out of the water, trying to be the first to catch the insect as it falls.

One of the most dedicated of noisemakers is New Zealand's Kakapo. This ancient, flightless, nocturnal bird is the heaviest parrot species in the world (weighing up to 3.5 kilos/8lbs). Like frogs, it has an inflatable air sac in its throat, which it uses as a sound amplifier; it also excavates a hole of just the right proportions to reverberate the sound around. As with many island species, it is unfortunately under threat from more resourceful animals introduced from overseas.

A curious suggestion has been made regarding Fowler's toad of South Carolina. It has been argued (controversially) that some of the smaller males will sit in cooler parts of the pond while singing. It is contended that this is so their croak will be deepened by the cold air, rendering them more attractive (to the female of the species, that is). Actually, properties of the atmosphere or sea are often used by creatures to enhance their signalling capacity. They take advantage of various 'sound windows'. This is why the dawn chorus takes place when it does, and why many animals signal around the hours of dusk and dawn: sound travels better in the colder, less windy conditions. Because of the greater wavelength of low-pitched sounds, they generally travel better (longer wavelengths don't jiggle up and down as much, so are less likely to bash into obstacles and peter out). Elephants and lions, by virtue of their size, are well-equipped to take advantage of this; so are whales. A sound window that evolution 'took into account' when 'designing' whales is the one located around 20hz - between the higher-pitched noise from storms and surface turbulence, and the deeper sounds from small earthquakes. Interestingly, a long-range sound transmitter developed for military use happened to sound very much like a muzzy whale call.

If there's a corner to be cut, evolution will often do it. As there are animal megaphones, so there are animal ear trumpets. Consider that peculiar structure, the external human ear.* Although well-designed for its task, it is not the most effective of sound-focusing mechanisms. One candidate for the title is possessed by the owl. The large depressions around their eyes are in fact sound funnels, just above which are located their exquisitely sensitive ears.

* The ear illustrates how human attractiveness is subjective rather than absolute; in absolute terms (if such exist from an aesthetic point of view), we and our simian relatives may be gangly horrors.

Although all these abilities are admirable, it is generally more energy-efficient not to waste body parts as specially-constructed tools. The reason for this is that animal bodies are generally made of flesh, bone or similar substances; as well as being expensive to synthesize, the range of available forms, sizes and consistencies is limited. As a rule, therefore, an animal is better off constructing tools outside its body - using sticks or stones to break bones, to hide, or to keep warm.

A species of mole cricket digs a burrow shaped like a two-horned megaphone; a metre away, the sound is a booming 90 decibels - the volume of a loud party* or of a power lawn mower at a distance of 50 feet*. When building this structure, it keeps testing its size until it resonates at the same frequency as its wings. On a quiet night, this 5-centimetre-long creature can be heard 600 metres away.

If nature can kill two birds with one stone, it often will: some crabs use their burrows as resonators.

Mammals are lucky that the ant lion larva is as small as it is. If you've seen 'The Return of the Jedi' - third in the Star Wars film trilogy - you have an idea of its modus operandi . It excavates a sand trap by spitting sand from its mouth, and waits at the bottom. For two or three years, it lurks at the bottom of the pit; whenever an ant ventures over the rim, it slips down the tractionless slope, into the larva's jaws. The ant lion punctures the ant's abdomen, and sucks its insides dry. This done, it spits the ant's husk out over the rim, to join the debris of ant skeletons.

Some predators are more proactive in their use of tools. Sea otters will use stones to crack open shellfish. Some birds will grip a stick in their beak, and use it to probe under bark; any insects climbing up the stick are quickly pecked into oblivion. The bolas spider catches moths by emitting a tempting scent, and then dangling a thread with a sticky blob of goo at the end.

One of the cleverest uses of tools (other than by humans) is by the chimpanzee . It makes a slender branch into a stick by stripping off the excess parts; it then uses it to probe insect mounds. The enraged ants or termites, thinking their nest under threat, run up the stick; the chimpanzee licks them off with relish (there is an eccentric Englishman who has adopted this custom - his main diet, I have heard, is ants).

Japanese macacques are one of the most interesting of primates. Their culture incorporates several uses of tools to make their lives easier. The ones who live high in the mountains are exposed to extremes of cold; it is thought that a female, by watching humans immersing themselves in the hot springs of the area, learned to keep warm by hopping in herself. The habit soon caught on with her fellows. These days, she is old and rickety; she stays in the springs, keeping her old bones warm, long after the other macaques have left.

The macaques which live on small islands off Japan have several tricks up their sleeve. They are fed sweet potatoes by the scientists who study them; 40 years ago, a young female learned to remove the grit and give the potatoes a pleasant salty flavour by washing them in the sea - now, all of them do it. Another food-cleaning strategy is to drop sand-coated wheat onto the water's surface; the sand sinks, leaving clean and agreeably salty wheat for the macaques.

We all know of the octopus and its jets of ink. Less well-known is the instinct of the water vole, which, when threatened, dashes to the river bed and kicks up a muddy smokescreen before (it hopes) making good its escape. This may seem less impressive than what the octopus does; but if you think about it, it's probably a better system for the vole. The rivers it lives in are shallow, and their beds muddy; it would simply be a waste of energy for the water vole to synthesize its own smokescreen.

There is a Javanese gobi that has engineered an original way of not attracting its main predators, birds. Rather than camouflaging itself as a leaf or twig (which would probably restrict its range of movement), it manoevres a leaf above itself, and swims upside-down, holding the leaf in place with its belly fins.

It is unfortunate that people often judge animal behaviour by the same standards they use to judge their own species. For example, the hyaena is largely reviled by humans, who see the animal as shirking 'honest work', and as undermining the hard-won success of the predators from whom it steals catches. This way of looking at animals (i.e. the 'nice, friendly' dolphin, or the 'sneaky' hyaena) is simply not appropriate. I will use hyaenas and dolphins as examples in an attempt to illustrate why the affection or dislike we feel for particular animal species is often misguided.

• First of all, the dolphin is as much a 'vicious' killer as the great white shark or the lion; the difference is that the prey is usually small fish, who we do not often see being killed, and with whom we have little empathy. Also, we cannot picture ourselves being killed by dolphins.
• Secondly, the hyaena is an excellent hunter, with a huge heart which allows it to chase and wear down its intended prey over long distances.
• Thirdly, dolphin males are not averse to gang-raping females.
• Fourthly, dolphins have been known to toy with and kill the loveable and intelligent porpoise.
• Fifthly, the hyaena - like most canines - has a very tight-knit social structure which involves much loyalty and affection.
• Sixthly, dolphins are not permanently smiling; the mouth structure of some species has accidentally converged with that of a human smile.
• Seventhly, and most importantly, it is simply not appropriate to think of these animals in human terms; they, like us, are acting within firm design constraints. If the hyaena's ancestors have been scavengers for thousands of generations past, how justified are we in labelling them cowardly shirkers? Should we demand that they go hungry rather than steal another animal's food? Nature (using her tool, evolution) doesn't work like that. Likewise, why should we give dolphins credit for being sociable, or lions credit for being courageous, if that is simply part of their design? Of course, I have nothing against dolphins; they are remarkable animals. But so, in their way, are hyaenas, and all the other creatures which are maligned by humans. Dolphins, hyaenas, spiders, protozoans - all have evolved into their present form because that was an excellent way to make a living out of their environment. All creatures are wonders of design, and it does them a disservice to portray them as acting out scenarios from the human social repertoire.

Now that that is off my chest, I will talk about those animals which have come to use one of the best tools - other animals. Wild dogs and cheetahs are among the best hunters in Africa; yet they are both rare. This is (in part) because catching your prey is only part of the problem; keeping hold of it is equally important. A key to the hyaena's success is its threefold strategy. The ideal is to let other animals do its hunting for it; then it can use its size and fearsome jaws (which can crush bone and bite through crocodile hide) to muscle in on almost any kill. If it can do neither of these things, it is an excellent hunter in its own right; unlike cheetahs and to a lesser extent wild dogs, it has its bases covered.

The honey guide is a 'kinder, gentler' animal. As the name suggests, this bird makes its living by leading animals (honey badgers or people) to beehives, so that the bigger animal will break in and free up some of the beeswax for the bird. The honey guide makes a special display which is recognized by the badger; the badger follows it to the fearsome meal. The honey badger also has less welcome companions. The chanting goshawk will follow the badger around as it forages; the bird carefully avoids coming within reach of the bad-tempered creature, and seizes any morsels of food - such as escaping lizards - which the badger is not quick enough to snap up.

[explanations later - maybe! It's a tough one. Suggestions welcome]

There are innumerable examples of insect cuckoldry; I will describe three of them here. Queens of many bee species always lay their eggs in the hives of others. As with many slave-taking ants, their bodies have been modified in accordance with their parasitic habits; they don't have the pollen-collecting apparatus which most young queens need for finding and storing food for their first brood.

There is much 'cheating' and manipulation involving the chemical signals of ants. One of the insects to exploit the ant communication system is the large blue butterfly, which mimics the chemical signals of ant larvae. The ants drag the butterfly into the their nest and care for it as their own.

Some beetles have developed the ability to impregnate at a distance. When mating, the penis of male flour beetles employs its spiny appendages to scrape out the seed of previous lovers. But these flour beetles are promiscuous animals; the female's present partner could well go on to mate with other lovelies. Because of this, evolution is presented with an opportunity: if lover No.1's sperm is sufficiently gooey, it may well adhere to the member of lover 2. If it can stick around until lover 2's next sexual encounter, there is a good chance that the new partner will be impregnated by lover 1's semen - according to researcher Matt Gage of Liverpool University, about one time in eight. So it has been suggested - and I think it likely - that flour beetles with the stickiest sperm have been the most successful in the mating game, and therefore that genes for viscid lovejam have spread through the population¹.

Corn has one of the most brilliant and convoluted of 'lazy' strategies. This plant is often lunched on by caterpillars. When the caterpillar's saliva comes into contact with chewed-up corn leaf, chemicals known as terpenoid volatiles are released. These attract the caterpillar's predator, a wasp,

which proceeds to lay eggs in the caterpillar. When the eggs hatch, the wasp larvae will devour the caterpillar from the inside out. In effect, what happens here is that corn recruits murderous 'bodyguards' to its cause. As a plant, it cannot move or resist the caterpillar; but it overcomes these limitations by engaging in a symbiotic relationship with the wasp. Such arrangements are not unique; a similar triangle exists between garden beans, aphids and parasitic wasps [John Downer, "Supernatural", pg. 22]. Other insect bodyguards are described above.

As you might expect, not all species of wasp sit around waiting for corn to be gnawed. Wasps kill and eat many creatures, some of which are themselves tough customers; scorpions and spiders are among their many victims. Another is the cockroach, which meets a very peculiar death at the hands [sic] of Ampulex compressa. After being stung by this wasp, the cockroach doesn't writhe in agony or slowly stiffen; it starts to groom itself furiously and incessantly, whereupon Ampulex takes it away and lays eggs in it. The resulting larvae will feast on the cockroach's insides.¹

Some trees are killers on a large scale. Not all of them are limited to mere jostling for access to sunlight. A few species are able to survive fires; of these species, some actually encourage blazes to start. They produce "abundant, and highly flammable, litter. In dry conditions this is liable to ignite spontaneously and the resultant fire eliminates competitors" [Allaby & Lovelock, 'The Great Extinction']. If species in fire-prone areas are incapable of surviving fires, they can still profit by producing seeds which only germinate after a blaze has passed through; with the area largely cleared of trees, the sun's rays become accessible once more, and rapid growth can take place.

Animals: the even more unbearable lightness of being?

On this planet, humans are number one; we generally act accordingly. It's easy to argue that we're pulling the environmental rug out from under our own feet; other people can put that case better than I. Personally, I think it's probably right to treat humans as Earth's most valuable species; we're the most intelligent, most creative, and (I think) probably the most conscious. But I also think we've gone too far; at least some other species should be given rights too.

Why?

I think that whenever a creature is conscious and has feelings, you shouldn't mistreat it - unless there's a very good reason. But how are we to know whether animals are conscious and emotional? The answer to that question has important implications for how we should treat animals.

Horrific tomes have been written on the subject; I'll try not to get bogged down in nightmarish philosophising. So here's my take on it.

I think it highly likely that some other animals have a degree of conscious experience; but it's currently impossible to prove. Although it's difficult for you to prove to me that you are conscious, commonsense - drawing an analogy with my own consciousness - dictates that you are. But other animals are relatively different from us in how they act, how they look, and how they communicate; so it's very difficult to make guesses about whether they're conscious. Usually, people draw analogies with between animals and humans, or just use their intuition. But these are flawed (though not entirely useless) methods. As you can easily appreciate, the fact that a creature is like us in some ways doesn't imply that it's like us in others. And if - like a computer - it looks and behaves very differently from us, that doesn't preclude it from harbouring intelligence or consciousness. Human intelligence is only one form, and it is easy to conceive of very different and much more advanced intelligences - machine or alien.

Nonetheless, I consider the following - quite straightforward - reasoning to be highly suggestive of conscious experience among animals.

When an intelligent animal is awake and active in the world, the processing of incoming information which takes place is immensely complicated - there is a vast range of levels of analysis, including memory, analogy, sequencing, and so on. But are there enough to bring about the emergence of animal consciousness?

It has repeatedly been shown that the differences between humans and the other intelligent animals are almost all of degree rather than of kind; although many of the components of human brains are more highly developed than in any other animals, all or nearly all of those components exist in some or many other animals. It surely cannot be reasonably argued that consciousness emerges from those minute parts of our brains which only exist in humans; such a dumbfounding phenomenon as consciousness must be the result of exquisitely-engineered interactions in large amounts of neural tissue. Now, since some other animal brains have the same areas (some in different proportions) as human brains, and since the interactions between these areas are of the same kind as in humans (although sometimes less complex), is it not logical to conclude that the differences between human minds and those of higher animals are also of degree rather than of kind?

If we are willing to kill and eat other animals which are less sentient than ourselves - but apparently sentient nonetheless - why shouldn't we allow ourselves to be eaten by artificially 'improved' - and therefore more sentient - beings? Either the cut-off point for who (or what) to eat does not exist, or it exists just below the least (neurologically) complex animal which may - as far as we can guess - have some glimmerings of consciousness. Do you agree?

Human cannibalism is dying out because people have come to recognise, abjure and forbid the suffering which it causes. Because it is less easy to appreciate the subjective experience of other animals, the repudiation of their breeding for slaughter is taking longer to gather force. Also, the pleasures of meat-eating are more immediate than the hidden cruelties of factory farming and the slaughterhouse. It's like lots of other things - if I wasn't so governed by my own ambitions and pleasures, I'd probably be off like a shot to the Third World to help out the people there. But I stay here. I don't exactly choose a complacent, selfish life, but I end up living it.

I would argue that rights should be given to every conscious animal. Obviously, it is silly to argue that all of them should have the same rights as humans - probably none of them are as conscious as us, and most of them are far less so. But this doesn't justify saying they should have no rights whatsoever. Each should be given rights that befit their level of awareness.

One of the greatest problems is to find out which animals are conscious, and which aren't. For the moment at least, this simply can't be done; we can only use guesswork. But does this justify dismissing the enterprise as unworkable? I don't think so.

Let me explain. Imagine you know that sometime today, an excellent sniper will maybe take a pot shot at you. You have a bulletproof jacket. Does your lack of certainty stop you from wearing it? (I'd probably say 'yes' just to be awkward. But just play along, alright?).

Even when you're uncertain about things, inactivity can itself be the wrong course of action. If you wait and wait for information that never comes, great injustices can be done. Ask victims of Gulf War Syndrome - they suffered while governments waited for scientific proof of its existence. We can't test animals for consciousness, let alone for degrees of consciousness; at most, we can make informed guesses. But that doesn't give us the right to treat them 'like animals'.

All of which may be very intellectually satisfying (or not) - but what we really need are changes to our laws. So what changes should we make? [more later - suggestions more than welcome.]

THE

MINDLESS

BRAIN:

Social Insects

Introduction

The ants in the picture are leafcutter ants. The workers of this species move along trees and shrubbery, cutting circular pieces out of leaves; it has been estimated that leafcutters divest tropical rainforests of as much as 20 per cent of their foliage². They carry the leaves to their nest; there, they clean them and chew them down to a pulp out of which they make their spongy homes. On this pithy surface grows a type of fungus which is unique to these ant colonies; other, less nutritious fungus species are removed by the workers. When a young queen leaves the colony, she carries a small piece of this fungus with which to nourish the new nest.

Why have the social insects evolved behaviour of such startling complexity? The main consideration here is the fact that all the members of a social insect colony share a 'germ line'; in other words, because they are sterile, their genetic future lies with only one member of the colony - the queen. Sharing a germ line is one of the most fundamental characteristics making an organism more than just a collection of cells working for their own interest. In genetic and in practical terms, although those who work for the queen are her (female) offspring, she is as valuable to them as a child is to a parent; she is the means by which the colony's genome - the genetic instructions for how colony members are made - will, if all goes well, survive, and spread via winged queens, eventually to inhabit millions of industrious bodies in other colonies. She is in fact more precious to them than a child is to its parents; because they are sterile, she is the only chance they will ever have of promoting their genes' survival. In addition, the unusual genes of ants make sisters more closely related than parent and offspring; this gives added impetus to the communal effort.

In effect, therefore, it is as if the queen had battalions of conscientious parents. This is why the social insects share the unity of purpose which is usually found in single organisms. They may be thought of as one organism with many parts; workers, soldiers, and the reproductive organs - the queen. Because this 'organism' has so many parts, each of which can roam independently of the others, social insects have properties which are never found in other (non-human) animals.

In computers, what is known as 'parallel processing' is considered to be essential to intelligence. In the computer that is our brain, for example, a vast range of tasks are being performed at all times - for instance, controlling heart rate and blood flow, calculating one's own trajectory and those of the other people walking along the pavement, processing the chaos of sound entering one's ears, combining the appropriate words, images etc. grammatically so that they form a coherent thought, planning what to say during a job interview, and so on. Whilst our consciousness itself seems largely 'serial' (focusing on one thing at a time), this serial process would not be possible without all the supporting activities which go on in parallel . When one scrutinises the minutiae of the brain, one does not find the mind; one finds countless brain cells performing a variety of calculations. Strangely, the mind emerges from this activity; its location continually shifts between huge coalitions of cells.

In a similar vein, social insect colonies display complex and seemingly intelligent behaviour; this emerges from the interaction of many simple parts, i.e. the individual colony members. This kind of organism can have a million pairs of eyes processing information from as many different locations; the other senses multiply the information processed by examining different facets of the environment - chemical, auditory, temperature, hardness, consistency, and so on. Many different strategies in the behavioural repertoire of this 'organism' can be activated simultaneously; one part deals with intruders, another catches slaves, another feeds the queen or larvae, others absorb heat from the sun above ground and carry it down to heat the nest; the range of strategies multiplies. It is almost as if a single brain was acting as coordinator; this 'brain', however, is made up of many separate pieces contained in the individuals of the colony.

However, the disparate structure of this 'brain' limits its intelligence: it cannot be coordinated with the speed of more complex brains; the various parts are not heterogeneous enough to possess a very great behavioural range; and, in spite of the complexity of the chemical signals emitted by the queen, there are comparatively few 'higher' 'neural' levels to coordinate activity. Nonetheless, as I hope to demonstrate, social insects have developed a formidable range of strategies by which to thrive.

Founding a Colony

The process of forming an ant colony can be said to begin when the young queens take off. This is the most dangerous stage of a queen's life, and most often the only stage; if she succeeds, she may live up to 20 years. They all take off synchronously; indeed, most ant colonies in an area will usually swarm with queen ants for a few days. The reason for this is to saturate predators such as birds, bats,

and other insectivores; as when swarms of mayflies turn the African air black, or when vast quantities of sperm are ejected in coral reefs, the environment seethes with more reproductive organisms than predators can gorge themselves on.

The more conventional strategy of queens is to begin a colony unaided. She will mate, and drop or bite off her wings. At this moment her chemical signature is formed; it will characterise the colony for as long as she lives.

She digs a founding chamber in a protected place; say between paving stones, under tree bark, or beneath a sheet of corrugated iron. She lays the eggs, and tends them until the first workers have reached maturity; the first workers are usually smaller than their successors because of the queen's limited food supply. If she is of a small species without sufficient fat reserves to sustain her, she must expose herself periodically by going out to search for food. Neither is she secure when in the nest; ants known as 'slave hunters' may wait for her to establish a colony, and then kill her, hijacking her offspring to work for themselves.

Some queens, however, also have devious tactics up their sleeve. They have evolved - by what mechanism I do not know - the following ability: the queen enters a foreign nest, and emits chemicals which distort the workings of the local soldiers' brains. They become frenzied, leaping in the air and snapping their mandibles together; they rush into the nest and, unbelievably, proceed to kill their own queen and install the usurper. Often, they work assiduously for the rest of their lives to protect the new queen.

Reed Mansions, Summer Homes, Mod. Cons.

Once the first workers are mature, they begin improving and enlarging the nest. The nests of ants come in many forms, some of them quite ingenious.

Oecophylla smaragdina has one of the most complex nest-building strategies among ants. The workers of this species wield their larvae in their mandibles; by applying light pressure, they induce specialised glands in the larvae to emit strings of silk. The workers pull leaf edges together; if leaves are too far apart for one worker to reach, groups of workers use the following method to build a bridge between the leaves:

Each ant walks to the end of the 'causeway of ant bodies' and lengthens it by placing her rear in the mandibles of the foremost worker. When the leaf on the other side is reached, the foremost ant grabs it and passes it to the ant behind her; she then scuttles back along the ant bridge and goes about other tasks.

Many ants build dome-shaped earth nests; this shape gives the nest greater surface area, thus allowing the ants to profit more from the warmth of the sun. The shape also, of course, gives off more heat when it is cold; but the domed part of the nest is only a 'summer home' for the ants - when temperatures drop, they retreat deeper into the ground, carrying larvae and pupae down through the tunnels with them.

Another strategy for saving energy by keeping warm is to build the nest under a relatively thin flat stone; this will absorb the sun's heat, continuing to radiate it during the night. The ants are opportunistic; pieces of plastic or other materials will serve just as well.

Evolution, the Mathematician

Beehives provide evidence of the potency of the original (and still the best) genetic algorithms - those which exist in DNA. Darwin wrote in 'On the Origin of Species' that

"[we] hear from mathematicians that bees have solved a recondite problem, and have made their cells of the proper shape [hexagonal] to hold the greatest possible amount of honey, with the least possible consumption of previous wax in their construction. It has been remarked that a skillful workman, with fitting tools and measures, would find it very difficult to make cells of wax of the true form, though this is perfectly effected by a crowd of bees working in a dark hive"

The bees must stand at the correct distance from their colleagues in order for the hexagonal cells to overlap considerably. This allows wax to be saved at the intersection points, whose thickness is of one cell wall rather than two. As Darwin notes, a certain flexibility has been built into their behaviour: "in cases of difficulty, as when two pieces of comb met at an angle, . . . often the bees would entirely pull down and rebuild in different ways the same cell, sometimes recurring to a shape which they had at first rejected."

The construction process itself is not all that complex; rather, the difficulty lies in actually finding algorithms of the requisite simplicity and appropriateness.

Farmers, Guest Workers, Shepherds

Symbiosis between ants and other species - plant or animal - is common. Because of their martial prowess, ants often act as guards for other species, who in turn secrete nourishment or provide shelter.

There exist plants which contain chambers designed to house a certain species of ant. For example, Central America’s Bullhorn Acacia tree has massively bloated, hollow thorns that house colonies of stinging ants. This is no act of generosity; the ants are extremely useful to it, serving its purposes in at least one of two ways. Firstly, the soldiers devour all insects which approach the plant; secondly, they can raze to the ground all neighbouring plants within a radius of up to a metre and a half. This enables the host plant to receive the sunlight it needs.

Some insect species, too, use ants as bodyguards. The payment which they give in return is usually to excrete a honey-like substance. The most well-known insect to live symbiotically with ants is the aphid; their ant bodyguards coax honey out of them by stroking them with their feelers. Some ants build special sections in their nest to provide shelter for 'paying guests' of this kind; other ant species take them to shelter when bad weather hits. Malaysian herdsman ants, Dolichoderus cuspidatus, are among the most diligent shepherds; they place honey-secreting mealybugs on plants to feed, and guard them. Like the army ants, they make temporary nests out of their own interlinked bodies; thousands of mealybugs are kept safe within the vast living mass. 4

Frank Lloyd Wright, the Marauding Butcher

One of the most superbly evolved social insects is the Army Ant. Because of the vast size of the Army Ant colony - it may number a million - it quickly divests an area of all insect life and of those larger animals which cannot escape. When an ant or group of ants comes across a prey species which it cannot tackle alone, it emits a scent which attracts more soldiers. The enlarged fighting organism can now swarm over the prey, dismember it and bring the pieces back to be eaten. Soldier ants of all species are extremely tenacious. I once observed two soldiers latch on to a wounded fly; when the fly managed to take off, they did not relinquish their grip. After a few airborne moments, the fly tired and crashed to the ground, whereupon the soldiers dragged the still-twitching insect back to the nest.

Because of the size of Army Ant colonies, they have to lead a nomadic lifestyle, eating everything in a locality and then moving on. Red Ants, which use similarly thorough search-and-devour tactics, are much valued as 'health police' by forest managers; they decimate local insect populations.

One of the most fascinating achievements of the Army Ants - or to be more accurate, of the DNA which evolution has crafted for them - is their ability to build complex nests out of their own bodies. When the queen is raising a brood, the ants stop in the evening, on low branches or between adjacent trees; they grip one another with their claws in such a way as to form a nest containing chambers within which the queen and larvae are protected, as well as corridors through which the larvae can be transported. This living nest can be fine-tuned to meet the climatic needs of the queen and her brood; the ants realize when the temperature needs to be altered, and open or close the corridors accordingly.

Conclusion

There is no mind in an insect colony; but it is brilliant nonetheless. Its cleverness resides in the two microscopic, intertwined spirals of which DNA consists. The behavioural complexity of social insects is more usually confined to those animals - such as ourselves - whose behaviour is not directly programmed by DNA. The most complex programming operation performed by DNA is to construct bodies and brain; your behaviour did not emerge fully-fledged at birth. DNA does not determine all of our behaviour; rather, it constructs the brain, and part of our behavioural repertoire, out of which a mature intellect can emerge as the brain learns about and interacts with its environment. However, the vast, closely-related societies of ants, bees and termites have given DNA the incentive it needs to 'program in' behaviour whose results are as complex and efficient as many of humanity's creations. This 'intelligence' is manifested not in any individual ant, but in the complexity of the behaviour which emerges from their interactions. It is, perhaps, only in the social insects that we can witness mindless behaviour achieve such brilliance.

Some intelligent species - for example orangutans - are relatively asocial. Sociability is only one factor - albeit an important one - contributing to the evolution of intelligence. However, if there is to be a 'cultural take-off', sociability is - at least among beings such as have hitherto existed on Earth - probably necessary; complex, highly advanced cultures require the interchange of an amount of knowledge and expertise which can, I think, only be contained in many minds (at least when we're talking about the kinds of minds that exist on Earth).

In the scientific community, it is quite frequently thought or assumed that on our planet, only humans have consciousness worth speaking of . In his book 'Animal Thinking', Donald Griffin draws attention to the fact that problemsolving, culture, creativity and curiosity exist in some of the other animals as well - and not only in those which are closely related to us.

Although many animals use medicines for specific ailments, I don't know how many of these behaviours are genetically-programmed, and how many culturally. John Downer writes that:

"If a chimpanzee is in pain or feels unwell it searches the rainforest for a cure, seeking the same leaves and herbs that are used as remedies by the local people. Like them it treats bacterial and fungal infections with leaves from the Aspilia plant and uses other plants to treat stomach upsets or rid the body of parasitic worms. Chimpanzees and the local people even use the same primitive herbal form of birth control, inducing abortions with Combretum and Ziziphus leaves . . . Other primates, including baboons, lemurs and vervet monkeys, also share many of the same medicines as East African tribes, using plants such as acacias, smilax and hibiscus to cure a range of ills. When baboons are suffering from diarrhoea they treat themselves with the leaves of the Sodom apple (Solanum incanum). When they are infected with Shistosoma worms, a harmful gut parasite, they destroy the infections with the fruit of the Balanites tree. Menstruating baboons even have a treatment for period pains, taking the leaves of the candelabra tree to ease their discomfort."

Zanzibar red colobus monkeys have learned to steal charcoal from charcoal burners; they use it to neutralize poisons*. The sheer range of medicines used by primates - especially chimpanzees - strongly suggests that learning is involved. Of course, learning isn't limited to primates. Birds, for example, culturally transmit information - they learn from each other (in Ireland anyway) that milk bottle tops yield tasty white stuff. They have also learned to distinguish between the colours denoting full-fat and low-fat milk (cunning little bastards. Our milkman recently switched from bottles to cartons; but this hasn't stopped them. In fact, I no longer have to open the cartons, as they obligingly peck holes in them for me. But it doesn't really pour straight). The intelligence of birds seems to be often underestimated (i.e. 'birdbrain'). In fact, the oft-cited genetic similarity between humans and the great apes should not be our guide to how intelligent an animal is; Steven Pinker writes that

'Three hundred thousand generations [the number that separates us from the common ancestor with chimps] and up to ten megabytes of potential genetic information are enough to revamp a mind considerably. Indeed, minds are probably easier to revamp than bodies because software is easier to modify than hardware.'

- How the Mind Works

We need to examine animals on their own merits, not on their apparent similarity to us - useful though that approach may be as a rule of thumb.

* Don't pregnant women sometimes get a taste for charcoal? I wonder if there's any connection.

There's another flaw which sometimes crops up in people's thinking about animal intelligence: structures that we describe as the product of intelligence when produced by animals with large brains are not described as such when built by animals with smaller brains. If chimps made webs like spiders we might think them incredibly clever. I do not wish to imply, of course, that the correlation between brain size and intelligence is not a strong one; it is. But it should not be assumed that because a complex artefact is produced by a relatively small-brained creature, that there is no cultural input, or that because something similar is produced by a chimp, that the input isn't largely biological. It is a useful rule of thumb; but we need to be a little more careful than that. Even many of the smaller brains in nature are very complex indeed.

Some species of antelope provide an example of curiosity in animals by approaching nearby lions to have a closer look, keeping at a safe distance of course. Seals will surface to have a look at passing boats.

A group of fishermen recounted the following story. A huge, dispersed group of orcas (killer whales) was interfering with the men's fishing by 'herding' the fish. The fishermen called in some whaling boats, whose crew proceeded to harpoon a female orca. Within half an hour, all of the orcas in the (large) area were avoiding the whaling boats, but not the fishing boats . The only consistent difference between the two types of boat was the protruding harpoon. It is impossible for all the orcas to have seen the female being hit by the harpoon.

If this story is true, it leads one to the conclusion that they must have a sufficiently complex 'language' to be able to communicate to each other the following information: 'avoid boats with stick-type thing jutting out of them'. The ability to organise and transmit such complex information is one which demands very advanced mental abilities; if this story (and the many other stories like it) be true, it is highly suggestive of consciousness in orcas. Unfortunately, though, good science cannot rely on anecdotes; research is needed if we are to draw firm conclusions about orca intelligence. Incidentally, orcas are the true masters of the ocean; they have been known to attack and kill great whites.

Especially in the past, humans have rarely given animals other than their pets the consideration which is merited by whatever their degree of sentience is.