Keith, thank you. Interesting stuff, though well beyond my field of competence. I read something the other day that suggested that now that we have the human genome we have a tremendous amount of data but still have to go about the far larger task of figuring out how it all fits and functions together.
I'm afraid I'm a little lost when it comes to who argues what in fields such the role our genes versus the environment play in our behaviour. I've read quite a lot of Pinker and know that he is roundly critical of Lewontin, Rose and the late S.J. Gould, though I'm not sure of what his criticism is based on. I find Pinker's approach rather mechanistic - we are wired to learn the things we learn and therefore to behave the way we do. He dismisses the possibility of a soul or spirit, which he labels "the ghost in the machine". He denies the possibility of innate human goodness, dismissing the "noble savage" with some sarcasm. He dismisses the notion, apparently held by a previous generation of anthropologists, etc., such as Mead and Benedict, that we are solely the products of our social environment, arguing that a "blank slate" is not prepared to do anything, whereas the human brain has built-in capacities that emerge as the individual develops. I've read somewhere that Lewontin and Gould have been labeled as "Marxists", but I'm not sure of how to interpret this except perhaps in the sense that man is something like a Hegelian synthesis of how his biophysical and social environment influences him and how he in turn influences his environment. This sounds a little like, within certain constraints, man can be what he wants to be and much depends on the choices he makes, but I'm sure it can't be as simple as that. Of course, being biologists, Lewontin and Gould would not restrict themselves to "man", but would be referring to all organisms. Perhaps they are suggesting that evolution is something about the ability to make choices and the constraints that are imposed on this. Our capacity to choose is far greater than that of a chimpanzee, which is why the chimp is stuck in the equatorial forest (or the zoo) but we find ourselves all over the earth. Compared to ourselves and chimpanzees, the ability of crabs to choose is enormously constrained, which is why they find themselves scuttling under rocks at the bottom of the sea. As for Dawkins, I've not read him, though he is associated with the rather fascinating concept of "memes" - mental constructs that are battling each other for survival and dominance by attempting to spread themselves throughout human populations. Perhaps in his view, genes behave the same way and are therefore behaving in their selfish interests, not in ours. However, I won't comment beyond that. The water's too deep for me. Ed ----- Original Message ----- From: "Keith Hudson" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: Saturday, February 22, 2003 3:00 AM Subject: Regulatory genes > Ed, > > I copied my recent FW messages to a molecular biologist friend to comment > on and he reminded me of what are called "regulatory genes", and perhaps I > ought to explain what these are in order to round out the picture I've > given so far. > > He was joking somewhat, because regulatory genes are presently the subject > of much research and they are very complex indeed. However, it's known that > some genes are not the "ordinary" genes that I've described so far -- that > is, one gene instructs a ribosome which makes one protein which does a > particular job in the body. > > It would seem that "ordinary" genes probably belong to sets or modules > which are influenced by "higher-level" genes. Thus, when the foetus is > developing, one regulatory gene may cause a module of other genes to kick > into action at a particular stage so they all act in a harmonious way. In > the adult, some regulatory genes may act for temporary periods only. If, > say, we fell into an ice-cold river, or we underwent a long period of > drought, then it's probable that in each case several genes will be turned > on by a regulator but then disassembled when a particular environmental > condition changes. It's as though our body is like a huge orchestra which > is playing a complex piece of music with its finer moments of > interpretation controlled by one section leader (leader of the second > violins, say) or another from time to time -- though not by a master > conductor. > > Although we have scarcely any more genes than a chimpanzee (about 1% more) > and our brains are structurally almost identical (though ours is larger > with a proportionately much larger frontal brain), we are certainly able to > think in different ways. It's likely that this is the result of the > evolution of regulatory genes in our spur of the primate tree from which we > separated about 6 million years ago. In some way, regulatory genes might be > able to organise modules of neuron-forming genes which the chimpanzee > cannot, and adding extra degrees of functionality to, otherwise, largely > similar types of brain cells. (Some think that the failure of a regulatory > gene is the cause of schizophrenia.) > > For example, a chimpanzee has a slight swelling of the left-hand brain just > as we do and which we call the speech centre. But a chimpanzee can't speak, > possibly only because its larynx is not in the right place. In our case, > the gene which moves the larynx further down the throat doesn't click in > until a child is about six months' old. But it *does* become turned on, and > it's likely that a regulatory gene has also evolved sometime which corals > this gene within a larger suite of "speech genes". The young child is > therefore enabled not only to make a quite new repertoire of noises but > these become associated directly with what are called "grannie" cells in > the speech centre in which the meanings of words are concentrated. > > I think Richard Dawkins did a great disservice to the wider understanding > of genetics and evolution by calling genes "selfish". This is nonsense. > They are no more selfish than they are unselfish. They just do what they > have to do, no more and no less. They are purely automatic mini-factories > churning our precise products which the structure of our bodies need. They > are either turned on or turned off, or they are regulated to work in > association with others, or not, but they can no more "decide" what to do > than fly in the sky. I think Dawkins' early books (e.g. "The Extended > Phenotype", "Selfish Gene") are quite brilliant, but his use of the word > "selfish", which has unfortunately stuck, has exposed molecular biology and > evolution to a lot of unnecessary criticism. > > Indeed, I find that in his later books which are intended to promote > science (his professorial chair is supported by Bill Gates) he becomes as > evangelical in his own way as the fundamentalists he constantly attacks. I > find his recent books quite as tedious as any fundamentalist tract. He > protests too much. He condemns the fundamentalists for having a faith and > yet wants to retain the right to his own! (The faith that science is > capable of explaining all.) He ought to shut up and quietly get on with > developing his science. The development of molecular biology for the > benefit of mankind (and of the ecosystem generally) is a much more eloquent > way of undermining arguments of simple-minded creationists. This would also > obviate the disgraceful criticisms of Lewontin, Rose and others, which take > up so much time of many other scientists to rebut. > > Keith H > -------------------------------------------------------------------------- -- > ------------ > > Keith Hudson, General Editor, Handlo Music, http://www.handlo.com > 6 Upper Camden Place, Bath BA1 5HX, England > Tel: +44 1225 312622; Fax: +44 1225 447727; mailto:[EMAIL PROTECTED] > ________________________________________________________________________ _______________________________________________ Futurework mailing list [EMAIL PROTECTED] http://scribe.uwaterloo.ca/mailman/listinfo/futurework
