25 July 2013

What makes us so different?

What is it that has enabled humans to so vastly surpass all other animal species in our degree of control over nature?  The difference is indeed huge.  The cutting edge of the technology of our nearest relative (and strong candidate for the Earth's second-most-intelligent species), the chimpanzee, is the ability to strip leaves off a twig to make it useful for sticking into termite mounds to gather termites to eat; the cutting edge of human technology is represented by the internet, interplanetary space probes, and stem-cell therapy.  Moreover, human technology advances at an ever-faster pace, while chimpanzee technology, if it changes at all, moves (as best we can tell) as slowly as that of our ancestors of millions of years ago.  To put it in the crude but important terms of sheer power, over the next century the survival or extinction of most other animals on Earth will depend largely on decisions made by humans, but the survival of humans will not depend at all on decisions made by any other species.

Is it intelligence?  Chimpanzee brains are about one-third the size of ours, and they can solve surprisingly complex problems in laboratory settings quite unlike anything they are adapted to in nature.  Insofar as intelligence is measurable, they are surely at least one-third as intelligent as we are.  That's not a big enough gap to explain the gulf between the termite twig and the Mars rover, surely.  The other great apes, and some other animals such as elephants, dolphins, and whales, also show signs of impressive intelligence, but none has technology even as advanced as the chimpanzee.

Tool-making used to be considered the defining human attribute (it was known that other animals used tools, but believed that only humans made them).  That ended in 1960 when Jane Goodall observed the above-described chimpanzee twig-stripping behavior.  Modifying a natural object to render it useful qualifies as making a tool.

Is it language?  There's growing evidence that language is not unique to humans.  Dolphins appear to use names, and we are still struggling to understand just what the other noises they make really are.  Apes can learn sign language to a surprising level, which suggests that they might have language-like communication systems in the wild -- language ability would not evolve in a species that never used it.  There's evidence of sounds with specific meanings -- "words" -- among vervet monkeys and even prairie dogs.  None of these have the complex grammar of human languages, but again, the gap is not as wide as we like to think.

(There are those who say humans have souls and other animals don't, but I'll assume no one who reads this blog believes in souls.)

I think the answer is writing.  It's hard for people who are used to using writing all the time to grasp the tremendous limitations imposed by doing without it, or to realize the impact of being able to store information permanently outside our own bodies.  People without writing cannot learn anything unless they directly experience it or it is spoken aloud by someone else within their hearing.  New insights die with the person who thinks of them, unless they are verbally passed on, and any information not of immediate practical use is likely to degrade into gibberish in a couple of generations if it survives purely through verbal transmission.  That which is written down, even in crude impressions on a clay tablet, can be read exactly as written by anyone else who knows the writing system -- even a hundred years later or a hundred miles away.

Writing made the accumulation of knowledge possible -- no longer limited by the capacity of the human memory or by the accuracy with which it could be verbally repeated.  This accumulation of knowledge caused a dramatic speed-up of cumulative technological progress.  As writing and civilization spread to more and more societies over thousands of years, and the number of literate humans with access to accumulated knowledge increased, progress speeded up at an ever-higher rate -- until today, just six thousand years after those first clay tablets, here you are, reading this on the internet.

Some might object that the invention of writing is very recent -- that six thousand years is only a small fraction of the time that anatomically-modern humans have existed.  And I would say yes, but before the invention of writing, humans were not substantially more sophisticated or powerful than other species.  We lived in small hunter-gatherer bands, as chimpanzees still do, with somewhat more advanced weapons, but almost as much at the mercy of the environment, predators, disease, and starvation as other animals are, and hardly more knowledgeable about the world than they are.  An alien visitor to Earth 10,000 years ago might not have found it at all obvious that humans were a unique species destined to dominate the planet -- he might have been more impressed by, say, the huge "urban" colonies and sophisticated agriculture of leaf-cutter ants.  An alien visitor today could identify the Earth's dominant species instantly.

Don't forget, too, that inventing writing seems to be only barely within the capabilities of human intelligence.  Almost all humans can learn to read and write, if taught, but the independent invention of writing happened only twice, or perhaps three times, in human history (by the Sumerians, the Maya, and perhaps the Chinese).  Clearly it was far from being an easy or obvious invention.  But it is this apparently prosaic ability -- to convert our spoken languages into marks on a surface and back -- that has given us the world, and will soon give us the universe.

[This post was prompted by reading this a few days ago.]


Blogger uzza said...

Interesting thought. Nice how you framed humans as 'different' rather than 'unique' btw. Nitpick: writiing isn't just for spoken languages anymore.

Apes can't read and write but they can come eerily close to it with their use of lexagrams. You might like this link.

Whatever the difference is, it's more nuanced that merely putting words on paper, and there's some exciting research going on .

25 July, 2013 20:21  
Anonymous Lady Freethinker said...

Love this -- and here's an interesting article about how cats' perception of human psychology is superior to our observations of our own species http://www.psychologytoday.com/blog/bear-in-mind/201110/why-cats-should-teach

27 July, 2013 02:54  
Blogger Infidel753 said...

Uzza: I've read about Kanzi and the lexigram project. It would be interesting to try to teach the system to apes in the wild and see if it "stuck", though it's hard to see how they would write the symbols.

Lady Freethinker: Thanks for writing the original post that inspired this.

27 July, 2013 04:28  
Blogger Michael Cargal said...

The folks at Language Log have looked into the claim that dolphins use names and found it untrue. The noises do not function as names.


27 July, 2013 06:34  
Anonymous skeptonomist said...

Wrong. As Darwin pointed out, primitive man had already occupied most of the earth before most of the things we associate with civilization were developed, and this includes writing. Human population has increased enormously thanks to agriculture, but we have not extended our range much at all. Was writing required for agriculture? This is a question that might be answered by historical anthropology, but there is no obvious reason that growing crops needs writing. At some stage more advanced technology kicked in, especially exploitation of fossil fuels, and a lot of that is hard to imagine without writing, but man was already one of the most adaptable single species ever in a fairly primitive hunter-gatherer state, without writing. It is much more likely that language itself was critical, but not writing.

27 July, 2013 07:55  
Blogger Ten Bears said...

You don't find that with a history spanning upwards of three million years our sudden - just ten thousand or so years ago - development of language and arts rather odd? Both the Summerian and Mayan texts you mention, as well as Indian (India Indian) of equal antiquity provide ample... interperation, if you wish, that aliens did indeed visit earth and finding the daughters of men beautiful paid considerably more attention to humans than leaf cutter ants.

I would argue the demarcation is in the recognition there are no gods, only fairy tales.

27 July, 2013 08:02  
Anonymous Deborah Mitchell said...

Interesting post. I never really thought about how important writing was to our development. I guess it helps with the accuracy of our information. Amazing how much we learn in 2nd and 3rd hand.

27 July, 2013 15:00  
Blogger Infidel753 said...

Michael: I'd seen that, but didn't find it particularly convincing. I think they misunderstood what was being claimed.

Skep: True, the human race increased its geographical range greatly before the advent of writing, but it didn't make much technological progress during that time -- technology 10,000 years ago was barely above the chimp level compared with what we have now or even compared with what the Romans had. The technological innovation which allowed our numbers to increase so dramatically followed the invention of writing.

Ten: Nobody knows how old language is. The Neanderthals might well have had it. Since apes have some language ability, human language might go very far back indeed. As for aliens, there's no evidence whatsoever suggesting aliens have ever visited Earth. If aliens existed, they would not find humans "beautiful" nor vice-versa.

The "recognition that there are no gods" didn't become widespread until a couple of centuries ago, far too recent to have been an influence in the early rise of civilization, though there have always been a few especially-thoughtful people who could see that religion was bunk.

27 July, 2013 17:20  
Blogger Infidel753 said...

Deborah: If you think how little it would be possible to know without writing, it's startling how dependent we still are on this 6,000-year-old invention.

27 July, 2013 17:22  

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