"Could you be dumber than a chimp? That's not as daft a question as it once was. After all, science has proved that chimpanzees share 99 per cent of our DNA. They can learn sign language. They can solve puzzles and even make tools. And this week came the most startling discovery of all.
Researchers in Japan have pitted human adults against five-year-old chimpanzees in a test of mental agility and memory - and the chimps won. In a test of short-term memory involving numbers flashed on a computer screen, the apes comfortably beat their human opponents. This astonishing result, published in the journal Current Biology, shows that in at least some respects our position at the top of the intellectual tree may be a bit shakier than we thought.
So what is going on here? Are chimps really brighter than us, even in this sort of memory test? And if so, what does this mean for the way that we treat them? After all, how could it be right to lock up creatures more intelligent than ourselves in zoos or laboratories? Most uncomfortably of all, can it be right to kill and eat creatures which may be less bright than ourselves but may nevertheless be fully sentient beings? In fact, the more science discovers about the animal mind, the less comfortable, philosophically, the findings become. And this has led to a small but growing movement that says we have to rethink our relationship with the animal world.
The traditional view of animal intelligence was a mixed one. On one hand, animals were thought to be inferior in all aspects to people; many religions, including Christianity, Judaism and Islam, teach that animals are essentially chattels, placed on Earth by God for us to use as we will. On the other hand, people have always ascribed emotions, intelligence and even 'rights' to their fellow beasts. People have always valued the companionship of animals, and many species have been venerated and even worshipped as gods. Until relatively recently, the scientific view has been equally confused.
While evolutionary biologists taught that people and apes shared most of their genetic make-up and were very closely related (humans are, in fact, a part of the Great Ape family, more closely related to chimps and bonobos than chimps are to gorillas), those who studied animal behaviour and intelligence continued to believe that humans had unique mental characteristics that put us far ahead of any other species. (Well, maybe not...)
Fifty years ago, for instance, science would have used several 'truths' to distinguish us from the other animals. First, they said, only humans have language. Equally, we are unique in having the ability to make and use tools. Surely only humans know they exist, as distinct entities? Finally, it was thought, only humans know they will die, and only we can recognise ourselves in a mirror or dream up gods and build churches in which to worship them. Now, though, things are rather different. Tool use? Many, many species are now known to use tools. Chimps can use moistened sticks to 'fish' for termites. Marine otters use rocks to smash open shells. And the ability of some birds is quite astonishing. A Caledonian crow called Betty made the headlines a few years ago when she was found to be able to fashion quite complicated hooked tools from bits of wire to fish things out of tubes. Even chimps cannot do this. Even some humans cannot do this.
Then there's the issue of speech: apes have now been taught elementary sign language, and there is some evidence that parrots who have learned to 'speak' English may actually understand the meaning of some words and phrases and not be merely, well, parroting the sounds that they have heard. Nor are humans the only animals that can recognise themselves in a mirror. Apes, possibly some birds and definitely elephants have now been shown to be able to do this. As to contemplating the future, the meaning of life and the certainty of death, we can never know what is going on in an animal's mind. But given how much we have discovered about animal behaviour in the past couple of decades, it would possibly be foolish to assume that we are unique in our abilities here either.
So what does this mean? Should the fact that we now know that some animals have hitherto-unsuspected mental skills change our attitude to them? The answer may well be that we should. The whole notion of human rights depends on our sentience and intelligence. If we accept that other animals are far more sophisticated, intelligent and sentient creatures than we thought, it would seem to be illogical not to grant them some rights too. The old soundbite that there can be 'no rights without responsibilities' is, of course, meaningless; we are happy to grant human rights to babies, the senile and the simple without demanding any responsibilities from them, so why not a chimp who would easily be the superior of any of these in terms of sheer cognitive ability?
These are uncomfortable issues. But scientists are now starting to address them seriously. For example, there is a growing movement, the Great Ape Project, which recognises that some species, starting with the great apes, should have a special legal status. It is already the case that many primates have protection under the law denied other species. It is, then, easy to envision a future where these rights are extended to other animals as well. The Australian philosopher Peter Singer has generated some outrage by proposing that full 'human' rights should be granted to any sentient creature. This would mean, he says, that in certain circumstances it would be morally correct to sacrifice a human to save the life of, say, a chimpanzee. This is an extreme view, but the very fact that 'serious' scientists are now debating such moral dilemmas shows that man's relationship with the animal kingdom is in need of reappraisal. There is, of course, a danger in reading too much into the latest research about chimpanzees' mental skills.
In reality, there is still no way we can consider ourselves to be less intelligent than the chimpanzee; this was simply one test, and it is not clear how much this sort of short-term 'photographic' memory equates with what we call 'intelligence' anyway. Apes are not people: they cannot build cathedrals, travel into space or find cures for diseases - but then again, nor can most humans. What the Japanese research does prove is that once again, a new and hitherto unsuspected ability has been unearthed in animals. And as science uncovers more and more about the animal mind, it seems as though the voices of those clamouring for a change in the way we treat these creatures will become louder and more plausible."