Friday, 2 March 2012

Who are we?

There was a discussion recently on a LinkedIn group on "What makes us human?". This focused on human behaviour traits, good and bad.

I'm not usually very literal-minded, but I had trouble with this one. I observe and display all sorts of human behaviour traits and I'm quite comfortable discussing human nature, but "What makes us human?" is either a question about mechanics to which the answer is "the instructions in our DNA, or rather a very tiny fraction of those instructions, as most of them could also make us chicken" - or it's inviting a comparison with something.

So what are we comparing ourselves with? Sometimes, as in "we're only human", we seem to be comparing ourselves with God, but as knowledge of God is highly disputable, that doesn't take us far except to emphasise our fallibility.

We know that we evolved bit by bit from a common ancestor with Chimpanzees, so our humanness, however defined, developed gradually and some of our quite marked traits are still basically common ape traits. In particular, studies of Chimpanzees show that some behaviours and perceptions we think of as very human are shared with them - for example, taking care of the dead and appearing to grieve over them, or something remarkably like ambitious people's office politics.

It appears that whales and porpoises are highly intelligent and dolphins probably even more so, but we are so different that we've understood little of the nature of their intelligence (we've also found it convenient not to probe into this while we kill them). The bodies of marine mammals are so different from ours that communication becomes fundamentally different and the marine environment, as opposed to land, almost certainly will lead to thinking differently. Besides, our concept of intelligence is so culturally determined that measures like I.Q. and learned discussions fail to recognise certain types of intelligence even among humans, so maybe if we knew far more about dolphins we wouldn't recognise - or wouldn't value - some of their intelligence.

If we had met even one extraterrestrial intelligent life-form (and survived) we could begin to answer the question "What makes us human?" because then we'd have a real comparator, a very different way of thinking, socialising and so on. We would find some things were common, so not distinctive of us, and others distinguished us from the other life-form (I'll leave machine civilisations out of it for the moment). Of course, just one comparator would not be ideal (imagine deciding what made us human by comparison with just one other earthly species, hippopotamus, say, or sea kale) and numerous comparators would be preferable provided none of them wiped us out.

Lastly, the mention of machine civilisations (much discussed in science fiction and somewhat in speculative non-fiction science) reminds me that when we ask what makes us human, we may be comparing ourselves with computers or robots. Now since some scientists see us as machines anyway, that's a difficult one, the more so because we sometimes build machines deliberately to mimic human thought processes and behaviour. Maybe I'll return to that - comments welcome.

Some answers would involve the soul, but while I'm comfortable with this idea insofar as I understand it, I'm not wedded to the Christian orthodoxy that humans only have something special.

I can't resist widening the extraterrestrial theme to say that our entire understanding of life and of how it arose on earth is constrained by a complete lack of comparators. If only we find something on Mars or on those moons of my lifetime, please...


  1. I ask only one question of you in this discussion, which is, if humans are 'relatives of apes', why are there still apes and monkeys? Surely common evolution would have moved all of the 'ape family' along on the advancements in evolutionary scale at more or less the same speed. I simply do not accept that contradiction as logical. Humans are 'different'. ":)

  2. Raymond - Thanks.

    By the same logic you advance for human evolution, as soon as one fish got out of the sea and became an amphibian, all the other fish would have got out of the sea and done the same. Once one New Zealand parrot lost its ability to fly and began excavating burrows, all the other parrots would have followed suit. Evolution just does not work by moving all species in the same direction - that's why new species evolve while old ones persist - and within one species undergoing "speciation" (the emergence of a new species) you will often find that the old species persists. This can happen very easily, for example, if one population get temporarily isolated by a land bridge being inundated or an inland sea receding till it divides in two. It can also happen if environmental pressures such as desertification or an ice age hit one part of the range much harder than the rest.

    In the case of apes, genetic studies show that there once existed an ape which was the common ancestor of hominids and chimpanzees. That population went in two different directions leading to chimpanzees in one case and humans in the other. During the evolution of homo sapiens, there have been several hominid species which have existed for a while and become extinct. Even the same environmental pressures can push evolution in different directions for different populations: for example, when the African forests dried out and receded, our ancestors left the trees for the savannah while other populations probably adjusted by staying among the trees but becoming smaller so they didn't need so much food. As for all apes following the human path, there was no reason why Orang-utans, for example, in their continuing Asiatic forest, specialised to take fruit from trees, should react the same way human ancestors did.

    Another factor is sudden changes through mutation. We now realise, as Darwin didn't, that life forms can suddenly emerge, mainly through natural radiation damage, with different characteristics which in over 99% of cases are a death sentence but which occasionally confer an advantage. The old species in its old lifestyle can still be perfectly viable as the new one with extra legs or different teeth exploits a new niche.

    I don't think any scientist is arguing for "common evolution". Evolution creates diversity. If humans are different, which clearly in some ways they are, I don't see that in any way contradicts their ape ancestry which is so clear in the genes and the fossil record.

    None of that is to deny the possibility that evolution might be nudged in certain directions. I've got into arguments on that one against purists.

    1. Sibathe, point taken. In Africa there are naturally radioactive hot spots. I wonder how many individuals parked their bodies on that land because it was warm--and mutated.
      I also wonder if devolution is even more likely. Try big-time removal of all of the modern tools, technology, food, clothing, equipment, communication, libraries and knowledge from all city-dwellers --and see how long it is before they are climbing around in trees for safety, foraging for food. A few generations and even minor mutation would do it, getting hairy and all. Interesting idea, isn't it?

  3. The theologian Karl Barth said that what makes us human is that we can laugh and smoke. Or something like that. The anthropologist Edmund Leach said that we are human because we can be irrational. I think that the differences between humans and other animals are a matter of degree rather than of kind. (For that statement to make sense, one has to understand the differences among all animals as being gradual.)I'd suggest that what makes us human is that we are no longer biologically adapted to any one particular earth habitat. Rather, our adaptations are cultural. And as far as I know we are the only species that proves mathematical theorems. And, in a nod to Leach, sometimes mistakenly thinks that we have a proof when in fact we haven't (eg Andrew Wiles and his attempts to solve Fermat's last theorem).

  4. Duncan - thanks for that erudite comment. Certainly we observe no equivalent to laughter among animals, though for all we know dolphins are doing something similar. I suppose to be able to be irrational, we must be able to be rational.


    I have often speculated (as science fiction does)about how humanity would react to a sudden loss of everything we've come to rely on. I suspect we wouldn't go back to hairy tree-hanging as there would be better adapted hairy tree-hangers to compete with, but we would certainly experience rapid evolution under pressure. Whether we would find our huge brains enough of an advantage to outweigh the disadvantages is an interesting question, but they did evolve in tough conditions. Science fiction also plays with rapid change in human populations isolated on other planets, and certainly something like a different level of gravity - even just slightly different - would have profound effects.