Tuesday, 28 August 2007

What's good enough for you?

Having recently finished reading the last Harry Potter, I've gone back to the book I was reading when Dylan took us by surprise and decided to pop out (I'm sure he regrets it): Richard Dawkins' Ancestor's Tale. The book basically takes us back from humans to the first origins of life, on the way intersecting with other animals we've diverged from and telling their tale. Currently, I'm with rats, which happen to be the 10th intersection out of 40 or so, and is estimated to have taken place some 75 million years ago. Or, to put it another way, if we were to meet our 15 millionth grandparent, we would meet the ancestor that is common to us and the rats (note the rat side of the family would have a significantly higher number of generations to climb up before meeting this common ancestor due to its shorter life span). A very interesting book, although its most noticeable attribute is its sheer thickness: at my current rate of reading I may be able to finish it in a couple of months.
While you may argue that no one is interested in the tale of some monkey or some rat, I find it quite amazing to see how much we can learn about ourselves from the stories of our relatives. The tale I want to discuss here is the tale of the new world monkeys, who - like most mammals - are partially color blind compared to us apes. We apes have re-developed the ability to see red, green and blue; the rest of the mammals are mostly stuck with two of those three. "Mostly" is the key word here, because these new world monkeys do not all share the same color vision attributes: some are blind to red, others to green, etc (and I'm talking here about one family of one species). In his book, Dawkins explains why this is the case: it is to do with the way color vision has mutated itself into the genes and the way the chromosomes pass on from one generation to the other (and the way they pass differently to the different sexes).
The point of all this story is that color vision between different people (I'm back to us humans now) is not the same. Different people have a different number of color sensitive cells in their eyes, each of those responding to a slightly different frequency. Thus, for example, some of us may see a more ultra violet version of blue than the rest of us; not to mention those that are color blind due to genetic reasons (about 2% of the population). Given those differences, it is clear that there is no hard wiring in the brain that allows the brain to know that a signal from a certain cell in the eye means "red" while a signal from an adjacent cell means "blue". There are just too many variations for that to be feasible.
So how do we perceive colors? The answer is simple: the brain learns to perceive colors. It notices that certain conditions trigger certain signals, and constructs a model that allows it to benefit from those changes - a model we commonly refer to as color vision.
It is clear to me now that the vision problems I have endured after my laser eye treatment were to do with my brain requiring some readjustments; things it has learnt to interpret in one way suddenly needed some different interpretation. This explains why the doctors told me my vision is perfect but I felt as though it wasn't, and this explains why now I no longer have such problems and I do [think I] see the world well.
Still, the question I ask myself next is when do we develop our color vision. The answer seems simple enough: as we first start using our eyes and as we go on using them. Now, I know someone who has just started using his eyes, and you can clearly see how he notices more and more with time. Whereas at first he would stare into space and only get attracted to light sources, now he can track objects, and he is obviously interested in things with sophisticated patterns and maybe even sophisticated colors (like some of the toys he has).
And now I'm asking myself: Am I supplying Dylan with the right stimulations for him to develop his vision properly? Most of the baby's development, in the sense of what he will grow up to be, is at the hand of his genes. We parents might like to think we have a saying in this, but the reality is that we have a very limited effect there: for example, the question of whether our son is going to be gay or not has probably already been answered by a certain mix of genes plus the quantity of testosterone in the womb (however, the environment still has a saying here).
One thing that parents can do which does seem to have an effect is to provide quality stimulants to the child that will arouse their intellect. For example, a child growing up in a house where people read books and books are available is more likely to end up reading books (just ask Uri). Which, in turn, makes me ask myself whether I am providing my son with enough stimulants; whether I'm providing him with quality stimulants. Am I failing my son by not painting the walls of his room with something exciting? Am I a criminal for not putting those posters of galaxies and other objects of the sky that I keep saying I will get up in his room?
Or, in short: Am I a good enough parent?

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