Monday, February 13, 2006
Re: [evomech] Pit-Loops
> In response to comments on another thread, here is another attempt
> to explain pit-loops.
> I kind of thought the pit-loop concept would be easy to visualize at
> least for people like yourself that understands systems design. Most
> likely I am not explaining the concept very well.
> Start with something like a neuron or a gene that needs to be
> activated or inhibited. The process or program that activates the
> neuron or gene can be described in terms of feedback loops or for
> complex processes as a set of feedback loops. Any computer program
> can be expressed as a set of input-output relationships, and any
> input output relationship can be characterized as a feedback loop.
> If the feedback loops are dynamic, programmable or self programming,
> and if the feedback loops serve a purpose or function, then the
> feedback loops fit my definition for pit-loops. Pit-loops are thus
> little more than an effective gimmick for reverse engineering the
> programs that control the development and operations of cells and
> complex organisms. If you analyze cells and organisms in terms of
> pit-loops, you quickly learn that evolution of living systems must
> involve the evolution or modification of pit-loops, not changes in
> I clearly don't have all the answers to what are all the pit-loops
> ultimately responsible for reprogramming other pit-loops, but
> following the results of pit-loop analysis might eventually lead to
> resolving the issue.
> Again, undoubtedly a most of the problem is that I am not expressing
> the concept clearly.
Although this is a discussion forum at the moment I don't have much time to 'discuss'! My enthusiasm at having more internet time has been somewhat dampened by persistent computer problems and this has led to a certain degree of frustration because I really want to get on with researching a rewrite of the area I'm interested in.
I do, however, read every post - and I'm sure that others do too - and sometimes I refrain from replying simply because the schedule at that moment in time is too demanding.
My overall impression of your posts is that you do have something to say. On the other hand I do feel a certain degree of reservation. It's purely a subjective viewpoint of course, but perhaps an analogy will convey the point I want to make:
Leonardo painted the Mona Lisa sometime in the early 1500's (er, I think). Imagine if Lamarck, instead of being interested in the natural world, had come along in at the beginning of the 18th century, dusted the painting off, and then wrote about the techniques Leonardo had used in the creation of his masterpiece.
Imagine if Darwin had an interest in art too. Fifty years later, with advances in science providing relatively more advanced methods of restoration, he might have uncovered information that Lamarck hadn't been able to access.
If this had been the case, then like many others, I can imagine reading about what they had to say and then going to Paris to find out for myself!.
This is not so easy to do in the field of evolution (although I would dearly like to be able to carry experiments!) and as a result of 'cultural conditioning' this appears to have led to some people believing that evolutionary theory defines the subject under scrutiny rather than merely reflects it. Cart before the horse?
Similarly, if any 'engineering/system principles' are found in the natural world it doesn't mean a) there's an engineer or b) that they define how evolution may occur. This may seem at odds with my own interest in the possibility of an internal evolutionary mechanism - I tried to explain this in this:
and the subsequent replies I posted on that thread.
Finally - and I'm trying to be helpful here rather than 'nagging' - you began this post with
>In response to comments on another thread".
People will be visiting evomech all the time. If they were to read this latest post of yours, would they then want to search for the other thread whose location/identity they don't know? I feel it would have been in your own interest if you had found this other thread, clicked on 'reply', and then posted - it would provide continuity and who knows what future response there might be!
Model of an Internal Evolutionary Mechanism:
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