[FRIAM] FW: Heritability and generative entrenchment

[Phil]

I'd agree entirely that a 'fitness landscape' could be complex, that
small changes in starting position could have large effects on what
pathways open up, that taking one path could alter it, etc..   I offer
what I think are good potential examples in my new paper offering a
curiously obvious radical new mechanism for evolution that you
complexity guys might (or might not) like.
http://www.synapse9.com/GTRevis-2006fin.pdf   The question is how to get
an *efficient* mechanism for a genome to explore the fitness pathways.
I think there needs to be some way for one change to result in a
multiplication of changes from it, i.e. some kind of feedback mechanism.
If there were branching structures in the genetic code or related
organizational systems of growth, which there are, that might do it I
think.  If a step in one direction is followed by any other kind of step
in any other kind of direction it seems inefficient at best.   


Phil Henshaw                       ¸¸¸¸.·´ ¯ `·.¸¸¸¸
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
680 Ft. Washington Ave 
NY NY 10040                       
tel: 212-795-4844                 
e-mail: pfh at synapse9.com          
explorations: www.synapse9.com    


> -----Original Message-----
> From: Friam-bounces at redfish.com 
> [mailto:Friam-bounces at redfish.com] On Behalf Of James Steiner
> Sent: Monday, May 22, 2006 8:46 AM
> To: nickthompson at earthlink.net; The Friday Morning Applied 
> Complexity Coffee Group
> Subject: Re: [FRIAM] FW: Heritability and generative entrenchment
> 
> 
> Another thought:
> 
> I think its important not to get locked into the view of 
> basins of attraction as a two dimensional construct. When 
> there are mutiple dimentions of change, a change in one 
> dimension may alter the landscape of other dimensions. In 
> other words, any local minimum in one direction may be 
> coincident with a flat zone of equally viable possibilities 
> in another dimension of change, but drifing through that 
> other dimension of change alters the shape of the original 
> landscape, possibly changing what was a basin to a slope or 
> peak. So "escaping" from any one basin of attraction is 
> really not so much of a problem, if there are other 
> dimensions of change still moving.
> 
> For a simple example, suppose an organism has optimized the 
> "number of limbs"--any mutation that changed that number 
> would be a less viable creature. But the "length of limbs" is 
> still changing--minor changes in length having little effect 
> for this number of legs, there is no basin, but a plateau of 
> equally viable possibilites, with some peaks around the 
> edges, where limbs that are too long or too short lead to 
> unviable options. But, suppose that as the legs get shorter, 
> the usefullness of having more of them increases, so as the 
> legs get shorter, what was a basin in the "number of legs" 
> landcape becomes a point on a slope toward "more legs". Now 
> mutations leading to more legs are more likely to be viable. 
> So, the organism escapes the basin, not by a radical jump 
> from one state to another, but by gradually changing the 
> shape of the landscape surrounding the basin until it isn't a 
> basin any more.
> 
> As the number of interrelated dimensions of change increases, 
> so does the variability of the landscape of any particular dimension.
> 
> So, in a system, like the DNA code that produces an organism, 
> that has millions of dimensions, I should think the viability 
> landscape is a very, very, fluid thing, indeed, and all 
> without any "annealing" at all.
> 
> If you add in the idea from my prior post that at this point 
> in time DNA may have evolved some ways of protecting its own 
> integrity, so reducing the scope and impact of "everyday" 
> mutations, we create a model where the overall 
> multi-dimensional lanscape of change is for the most part 
> like a flat meadow, where the effects of most everyday 
> mutations are viable, punctuated with narrow spikes of 
> unviability, with wild, treacherous formations along the 
> edges, where radical random mutaion (like that caused by 
> radiation, for example) for the most part ruins everything, 
> but can sometimes create something that works.
> 
> I should also read more--I expect I'm not saying anything 
> new, as it seems so simple and obvious to me, and perhaps I 
> am missing something.
> 
> Thanks,
> 
> ~~James
> ________________
> www.turtlezero.com
> 
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