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
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.
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.
|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.
|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
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.
|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.
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?
|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.