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(no subject)
2012
unknownj
I've been reading The Extended Phenotype by Richard Dawkins lately.. I'm only up to the third chapter or so, but that's just a natural consequence of it being a book where you have to read every paragraph twice just to make sure you get it..

I have a couple of criticisms of some of the things he says, but I'm slightly scared to voice them since he spends the first couple of chapters of the book saying "here's some people who disagreed with me, and this is why they're wrong".. Competing theories are fun :o)

One thing I disagree with though, and this is purely for my own reference, is one of the remarks he makes about genetic determinism. While he's largely against the idea, he still touches upon it..
If we steep ourselves in the implications of Weismannian orthodoxy, there really does seem to be something juggernaut-like and inexorable about genes. They march through generations, influencing the form and behaviour of a succession of mortal bodies, but, except for rare and non-specific mutagenic effects, they are never influenced by the experience or environment of those bodies. The genes in me came from my four grandparents; they flowed straight through my parents to me, and nothing that my parents achieved, acquired, learned or experienced had any effect on those genes as they flowed through.
I can't help but feel that he's mistaken cause for effect, and misapplied the anthropic principle. The fact that he exists now does indeed show that there are four grandparents whose genes he has inherited. But the fact that genes are largely immutable does not mean that their environment doesn't affect them. While he is correct in his assertion that he has inherited genes from four people, which are largely unchanged, the environmental factors determine which four people contributed to the end product. While individual genes remain the same, their phenotypic properties interact with the environment, and it would be foolish to assume that there was no feedback from that.

Sometimes the anthropic principle gives a false sense of cause and effect - the "I exist" cause gives rise to an "I have four grandparents" effect, certainly, but it is not specific. One can only take it so far as "I have four genetically viable grandparents whose phenotypes were compatible to the point where a second generation could arise", but that still leaves incalculable potential for variation. Therefore, the existence of an individual ought not to give rise to a fatalistic view that their genetic makeup was somehow predestined.

Specifically, where he says
nothing that my parents achieved, acquired, learned or experienced had any effect on those genes as they flowed through
I rather feel that the achievements and experiences of all his potential parents and grandparents determined which genes flowed through, which then allows for a far less deterministic model. All this is assuming that his perception of "self" is not inexorably linked to his genetic makeup, but that goes even further towards genetic determinism, which I know he does not subscribe to.

As you might imagine, halfway through the third chapter my imagination is already fired up, and my brain is slowly assimilating the information and adjusting my perception of evolutionary biology accordingly. The notion that individual selection borders on irrelevant, and that it is phenotypic selection of individual genes that powers the evolutionary process is one that I'd touched on during my degree, but hadn't really considered as a wider explanation for specific traits..

It's good to be reading again :o)

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If I understood any of that I'd make a comment. But as I didn't - I won't ... except:

I bet you are glad that you get your genes from your grandparents (at least from one set)



A comment - the statement nothing that my parents achieved, acquired, learned or experienced had any effect on those genes as they flowed through causes me some concern. If I have had no effect on the genes inherited from my parents and have just passed their genes straight through to you, wasn't the same true for me in that I got nothing from my parents but got mine from my grandparents; and so on. Is he saying that genes skip a generation? Sounds like a load of old bollocks!

Not entirely, given the tendency towards baldness ;o)

He's not saying the genes skip a generation - while you did not affect the genes, the genes affected you. What he's saying is that, given the identities of your parents, and the fact that I am your son, it is a certainty that half of my genes come from your parents. Regardless of anything you have done in your life, none of that impacts the genes you pass on, since they're hard coded.

A good analogy would be that of software. If we assume that individuals have just one parent, then copying software works in the same way. It doesn't matter what the actual piece of software is used for in its lifetime, a copy of that software will still be programmed in exactly the same way. In the same way, the things that a person does do not affect the way they were initially programmed to be, and the genetic code that they will eventually pass on.

Don't think I explained myself properly. Let me try again.

The genes you inherited were those of your grandparents that passed to us, your parents, but we didn't alter them. But surely the genes of my parents were in fact really those of my grandparents which passed unaffected through my parents. However, the genes of my grand parents were ... well I guess you've got the idea.

Does that make sense or am I being way too simplistic. The logical conclusion of parents being affected by but not having an impact on their inherited genes is that we are all basically just cavemen (or whatever we were when genes were invented).

Ummmmm, as I said before - load of old bollocks.


Not really... over thousands / millions of generations, variation, natural selection and occasional mutation help to shape a population and change it. But since there's bugger-all natural selection working over the course of two generations, it's fair to say that the few thousand deleterious mutations I've picked up in the two generations since my grandparents don't amount to a significant genetic change...

But what is it all supposed to mean?

That you are a bit like me and a bit like mum? Worse still, does that mean that I am a bit like my mother and a bit like my father - and the same as my brother???


BTW Any word on the job front?


BTW2 Don't like your LJ theme - I can never find the cusrsor position. Probably eyesight failing in old age.

Well yes, I'm half like you, half like Mum... Except I won't go bald.

Honest.

As for the job, nothing yet.. not expecting to hear about the latest thing until next week.

And I can't see the cursor either, but I'm too lazy to change.

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