Nature

You clever little beasts From tool-making to language, new research shows that animals share many of the attributes once believed to be uniquely human By Windsor Chorlton Not just a dumb bird... Hob the falcon "called his owner to help catch a pheasant Hob, a male falcon, is an excellent aerial hunter trained by Paul Gillott, a police inspector based in Dorset. Hob is also smart. For starters, he can recognise Paul's Lada car: one day, after becoming lost in flight, he managed to spot Paul's vehicle on the A303. He followed it, regardless of the heavy traffic, until Paul turned off onto a quiet road. Another time, after chasing a pheasant into a hedgerow, Hob emerged on foot and ran up to his trainer, vocalising in frustration. Ignoring the food he was offered, he ran back into the hedge, still calling. He did this twice, "Lassie-style", before Paul realised that Hob was actually demanding help, and decided to follow him - across a ditch,over a fallen tree, and through thick undergrowth, where he found the bird staring fiercely down a rabbit hole at the tip of the pheasant's tail-feathers. MEMORY Rhesus monkeys These animals can work out how to use sticks to retrieve "unreachable" yoghurt from the bottom of the tubes. In intelligence tests,rhesus monkeys tend to be more successful than squirrel monkeys,marmosets,cats,rats and squirrels Comparative psychologists never attribute "intelligence" to an animal if its actions can be explained by some simpler mental process. Applying this rule, they would say Hob's keen eyesight was what enabled him to pick out Paul's car. But acute sensory perception does not explain the incident with the pheasant. Hob hasn't been trained to solicit help to catch prey, nor is such behaviour innate in wild falcons. The only reasonable interpretation is that Hob was demonstrating what we would call intelligence - that is, using innovative behaviour to solve a problem. Many scientists shudder at the suggestion of animal intelligence. Despite our evolutionary link with other species, they still believe that we stand on one side of an intellectual divide, while on the other, animals blunder about like some kind of automata, driven only by blind instinct or environmental conditioning. Bit by bit, though, this gulf is being bridged as researchers discover that animals display many "human" attributes. One measure of intelligence is speed of learning, and despite the difficulties of devising a test applicable to animals with different sensory equipment, psychologists have made valid distinctions between the learning speed of different species. In one test involving six different species, rhesus monkeys came out top followed by squirrel monkeys, marmosets, cats, rats and then squirrels. This order tends to confirm the theory that brain power increases the higher the animal's ranking on the phylogenetic scale - which places primates and monkeys above the other mammals, which in turn are higher on the scale than birds, reptiles and fish.In fact millions of years of parallel evolution have given certain carnivores larger brains than some monkeys, whereas there is considerable overlap in the brain - size of birds and small mammals.

Who are you calling a bird brain?
Among birds, crows have especially large forebrains and display impressive resourcefulness Faced with the problem of how to transport scattered biscuits, ravens, unlike other birds, don't carry them off one-by- one. They stack them into one neat pile, and then carry them all off .
The woodpecker finch of the Galapagos Islands uses a cactus spine to prise insects out of crevices, while the Egyptian vulture smashes open ostrich eggs with stone.

TOOL USE

Sea otters use stones to open tasty shell fish. A hungry otter is capable of cracking 50 mussels in 90 minutes - delivering more than 2,000 blows in the process

Surprisingly, the only non-primate mammal known to use stone tools is the sea otter. It used to be thought that animals used tools for immediate tasks only, and then discarded them; but sea otters retain favourite stones, tucking them into their armpits when they dive for food.
In what is now Ghana, colonial forestry official W B Collins witnessed the extraordinary way in which driver ants harnessed a simple tool to break through the defences of a horde of snails. Driver ants can reduce a python to bones in an hour, but these snails initially repelled the ant army by secreting a foam-like mucus into the entrances of their shells for protection.
The ants deposited crumbs of dry soil in the mucus. As the liquid was absorbed, the snails responded by secreting yet more mucus, and in turn, the ants deposited more soil around the snails. This relentless attack technique was repeated until the snails had exhausted their mucus reserves and lay defenceless.

Tools of the trade
Tool-making by animals was first recorded in the 1960s by primatologist Jane Goodall, who observed chimpanzees stripping leaves off branches to fashion probes for fishing termites out of their nests In captivity,chimps display even greater ingenuity, wielding sticks to rake in food from outside their enclosure and stacking boxes in order to reach bananas hung high in their cage.
Impressed by feats like these, American psychologist Sue Savage-Rumbaugh and archaeologist Nick Toth mounted a project to see whether a chimpanzee could use one tool to make another - the breakthrough that launched early man's technological leap forward. As their apprentice, they chose a chimp called Kanzi.
First, they showed Kanzi how to produce stone chips by striking one cobble against another, then they demonstrated how the flake could be used as a tool to cut the string securing the lid of a food box. After that, Kanzi was left to his own devices. His efforts weren't particularly impressive, and, after a four-month period, he decided to try a new technique - hurling the stone at the concrete floor and smashing it to fragments.

LEARNING CURVES
After three weeks of trial and error,this squirrel figured out how to open a "squirrel proof" bird feeder. Intelligence coupled with daring acrobatics got the results

Reluctantly deciding that this wasn't the method used by early man, the researchers covered the floor with carpet, but within minutes Kanzi pulled back the carpet and again threw the stone against the concrete. Finally, he was turned out into an earth enclosure and this time he placed a rock on the ground, took aim with the hammer-stone and let fly. His handiwork may not have been up to the standards achieved by early man but he certainly learnt how to break rocks.

Those Machiavellian manoeuvres
Since chimpanzees are our closest animal relatives, sharing 99 per cent of our genes, it's not surprising that much of their behaviour resembles our own. The Greek philosopher Aristotle claimed that man was the only political animal, but at Arnhem Zoo in Holland, Frans de Waal found that his male chimpanzees were positively Machiavellian, forming shifting alliances in a struggle to gain access to females.
These group power struggles sometimes ended in death, and it was not always the strongest that triumphed. As de Waal explains: "The weakest of the three competing parties gain more by joining forces and sharing the spoils than by joining the strongest party, who then end up monopolising the pay-offs"

Animal philosophy through the ages

Soulful creatures 13th century Italian philosopher St Thomas Aquinas believed that all creatures and plants possess souls. Deus ex machina 17th century French philosopher mathematician and devout Catholic René Descartes believed humans to be set apart from the rest of creation.He viewed animals as unthinking machines, lacking conscious perception, but with God-given instinct. Abstract Limits 17th century English philosopher and scientist John Locke held the opinion that animals have perception, memory and reason but not the ability for abstract thought. A sliding scale of reason In the Descent of Man, he argued that "animals possess some power of reasoning" and that "the difference in mind between man and higher animals, great as it is, certainly is one of degree and not kind" Darwin's concept of instinct was similar to Descartes', with evolution replacing the work of God. Definite George George Romanes, a disciple of Darwin, wrote Animal Intelligence in 1882, the first attempt at scientific analysis of animal intelligence. He defined intelligence as "the capacity to adjust behaviour in accordance with changing conditions". Reflex action 20th century Russian biologist Pavlov was the first scientist to make a scientific study of learning. He performed experiments in which dogs learnt to associate the sound of a bell with food. Pavlov termed this response as "conditioned reflex". BF Skinner devised aptitude experiments for pigeons in order to show their learning capacity Skinner's rewards BF Skinner, one of most influential figures in learning theory and author of The Behaviour of Organisms, conducted experiments in trial-and- error learning used "Skinner boxes" which yield a food reward if the animal pushes the correct sequence of buttons. Songs to learn Biologist WHO Thorpe reared chaffinches in isolation to prove that their song development is not instinctual. They learn song from older birds. The mental map Twentieth century American psychologist Edward Tolman noted that the behaviour of most animals suggests sophisticated navigation. He argued that all animals have a "cognitive map" and some sense of direction. The beginnings of Ethology Niko Tinbergen and Konrad Lorenz are regarded as the founders of modern ethology (the science of animal behaviour). Their scientific system is still used by ethologists today. Researched instinct, learning and imprinting and won a Nobel prize in 1973. Tool use Primatologist Jane Goodall made ground-breaking discoveries in the 1960s with her studies of wild chimpanzees. She was the first to observe the chimpanzee's ingenious use of tools. Dancing Bees Zoologist Karl von Frish's discovered the bee language system, whereby the scout bees perform a sophisticated "dance" routine to communicate information to the rest of the hive about the exact location of new food sources. He shared the Nobel prize with Tinbergen and Lorenz in 1973. A chimp and human communicate by touching symbols on a keyboard Termite Society Biologist Edward Wilson studied social organisation in animal groups - particularly highly complex termite societies. He wrote the influential book, Sociobiology. Animal suffering Oxford zoologist Marian Dawkins wrote Animal Suffering. Her controversial work with hens showed that they prefer outdoor conditions to living in battery cages - and on release ,hens exhibit some of the same emotional responses as humans released from prison. Definite William William Hodos studied animal intelligence in relation to neuroanatomy. He said: "We must accept a more general definition of intelligence than one closely tied to human needs and values." Do animals have consciousness? Harvard biologist Donald Griffin is one of the leading scientists to advocate animal consciousness. In his book, Animal Thinking, he argues that "it is difficult to accept that mind and consciousness in humans have just arisen without any precursors in animals that were ancestral to us and probably very similar to the non-human primates that we observe now."

Deception seems to be a conscious strategy of apes, as Keith Lloyd, a primate expert at London Zoo, discovered when he was duped by a gorilla - a dominant silverback in a group where one of the females had given birth to a baby fathered by another male. Because infanticide by jealous male primates is not unusual, Lloyd carefully monitored the body language of the silverback to see whether he was hostile to the new arrival. All his gestures indicated he wasn't, so Lloyd left the group alone for a time and returned to find that the old silverback had killed the baby. "I'm sure he intended to lull me into sense of false security," says Lloyd, "fully intending to kill the baby as soon as I left."
To Harvard biologist Donald Griffin, the capacity of animals to deceive suggests that they have consciousness;they think out the best strategy and communication to produce the intended response.

MIMICRY
When Robert Gross was photographing a kingfisher, he noticed a robin always turned up, seemingly to observe the kingfisher's technique. The robin soon attempted fishing for itself - gradually refining its fishing technique over several months

Animals say hello
Evidence of intentional communication comes from research on wild vervet monkeys in Kenya. These monkeys utter three distinct alarm calls in response to different predators, and the other troop members respond appropriately: climbing into treetops at the leopard alarm; diving into undergrowth at the eagle call; and standing upright in a search posture for the snake warning. Slight variations in the signals among different vervet troops suggest that the calls are culturally transmitted.

In a comprehension test of 660 sentences, chimp Kanzi scored better than a two and a half year-old child

This looks uncannily like a proper language, mankind's crowning glory - the gift many scientists are most reluctant to admit that we share with other species. Linguists such as the influential Noam Chomsky assert that human language has no discernible evolutionary connection with any other form of animal communication. For one thing, animals can't communicate abstract concepts. Or can they?

DEXTERITY

They may not have a backbone, but they do have brains The octopus is the most intelligent invertebrate. In this sequence, an octopus quickly figures out how the cork in the bottle has to be removed in order to retrieve the shrimp inside

Try telling that to Alex,an African grey parrot trained by Irene Pepperberg of the North-western University in Illinois. Alex can discriminate between 80 different objects arid classify them according to shape, colour or material.
Mere mimicry and robotic conditioning, scoff the sceptics, who insist that the essential ingredient of rational language is syntax - the structural system to order words in meaningful ways. Yet the songs of whales contain syntax-like elements, and dolphins studied by Louis Herman in Hawaii understand commands made up of the same words ordered differently. For example, they know the difference between "Bring frisbee to surfboard" and "Bring surfboard to frisbee".
Most animal language studies have concentrated on chimpanzees which, as our nearest relatives, might be expected to possess some of the elements of true language. Cognitive scientist Steven Pinker disagrees, arguing that primate language is controlled by a part of the brain that in humans produces emotional utterances such as laughter, and the kind of involuntary oaths we utter when we suffer pain.
It's true that primates can't speak, but that's because they lack the vocal and neurological apparatus, says Sue Savage-Rumbaugh, who has taught chimpanzees to communicate through lexigrams - geometrical symbols arranged on a keyboard. Kanzi, the apprentice tool-maker chimp, spontaneously learned the meanings of some lexigrams and by the age of seven he could comprehend about 200.
His understanding of spoken language is so good that, in a comprehension test of 660 sentences, he scored better than a two and a half year-old human child. Findings like these may force us to reconsider the way we treat "dumb" animals. It seems that the more we delve into their minds, the more we find that we are different only in degree, not kind.

INDEX