Such a simple question. Many of you might think "Has that question really disappeared?" Some questions disappear for ever because they have been answered. Some questions go extinct because they were bad questions to begin with. But there are others that appear to vanish but then we find that they are back with us again in a slightly different guise. They are questions that are just too close to our hearts for us to let them die completely.
For millennia, human superiority was taken for granted. From the lowest forms of life up to humans and then on to the angels and God, all living thing were seen as arranged in the Great Chain of Being. Ascend the chain and perfection grows. It is a hierarchical philosophy that conveniently allows for the exploitation of dumber beasts — of other species or races — as a right by their superiors. We dispose of them as God disposes of us.
The idea of human superiority should have died when Darwin came on the scene.
Unfortunately, the full implications of what he said have been difficult to take in: there is no Great Chain of Being, no higher and no lower. All creatures have adapted effectively to their own environments in their own way. Human "smartness" is just a particular survival strategy among many others, not the top of a long ladder.
It took a surprisingly long time for scientists to grasp this. For decades, comparative psychologists tried to work out the learning abilities of different species so that they could be arranged on a single scale. Animal equivalents of intelligence tests were used and people seriously asked whether fish were smarter than birds. It took the new science of ethology, created by Nobel-prize winners Konrad Lorenz, Niko Tinbergen and Karl von Frisch, to show that each species had the abilities it needed for its own lifestyle and they could not be not arranged on a universal scale. Human smartness is no smarter than anyone else's smartness. The question should have died for good.
Artificial intelligence researchers came along later but they too could not easily part from medieval thinking. The most important problems to tackle were agreed to be those that represented our "highest" abilities. Solve them and everything else would be easy. As a result, we have ended up with computer programs that can play chess as well as a grandmaster. But unfortunately we have none that can make a robot walk as well as a 2-year old, yet alone run like a cat. The really hard problems turn out to be those that we share with "lower" animals.
Strangley enough, even evolutionary biologists still get caught up with the notion that humans stand at the apex of existence. There are endless books from evolutionary biologists speculating on the reasons why humans evolved such wonderful big brains, but a complete absence of those which ask if a big brains is a really useful organ to have. The evidence is far from persuasive. If you look at a wide range of organisms, those with bigger brains are generally no more successful than those with smaller brains — hey go extinct just as fast.
Of course, it would be really nice to sample a large range of different planets where life is to be found and see if big-brained creatures do better over really long time scales (the Earth is quite a young place). Unfortunately, we cannot yet do that, although the fact that we have never been contacted by any intelligent life from older parts of the Universe suggests that it usually comes to a bad end.
Still, as we are humans it's just so hard not to be seduced by the question "What makes us so special" which is just the same as the question above but in a different form. When you switch on a kitchen light and see a cockroach scuttle for safety you can't help seeing it as a lower form of life. Unfortunately, there are a lot more of them than there are of us and they have been around far, far longer. Cockroach philosophers doubtless entertain their six-legged friends by asking "What makes us so special".
ALUN ANDERSON is Editor-in-Chief of New Scientist.