Friday, April 14, 2006

Story time Pt. 1

I am a deciple of Darwinism. 'Natural selection' just might have been the two most insightful words ever uttered in history. I found my appreciation for the survival of the fittest model by pushing it as far as I could and seeing that even in extreme cases it seemed to have something useful to contribute, either in explaination or prediction.

Not always though. There has been the standing issue of the blood clot. A blood clot is a synthesis of about 50 protiens, all of which are necessary to make anything useful. I.E if you take any one of them away you get a protien soup rather than a blood clot. This is a problem for Darwinism which tends to build everything in small, independant steps. I now suspect that the clot was built in small steps up to 100 or so protiens then withered down to the 50 specialized protiens we have now. But to my knowledge a robust model is still pending.

There is also the problem of the inert gene sequences. Richard Dawkins helped with that problem by supposing gene-centric, rather than organism-centric, evolution in his book The Selfish Gene. In this same book was the seeds of the new science of memetics. Memetics helped me get over most of the other problems I had with Darwinism, but one major issue remains.

There is an understandable story that tells of how molecules on a lifeless earth came to be reorganized to build such wonderful things as the societies and institutions we have today. I have reason to believe such a story exists but that certain chapters of it have not been written yet. The major unwritten chapter in my story is the development of sexual reproduction.

With the help of memetics and Steve Grand's book Creation, I can follow how in the primordial soup there would have been created a few molecules that, by some aspect of their nature, directly or indirectly encouraged other similar molecules to be formed. These molecules would have undergone exponential growth until they reached some natural carrying capacity.

This point could likely have been the first time in history survival of the fittest was put into full effect. This is when the small variations in copying during the exponential growth would have given some molecules advantages over others to have access to the resources necessary to make further copies. The advantages would have been slight, perhaps not much more powerful than chance, but unlike chance these advantages would have been consistent and would therefore shape populations.

As the competition built innovation upon innovation, the molecules would have grown more complex. The larger molecules would now need many substances and catalysts to synthesize themselves and could now be seen to amass them in a sort of bag, perhaps with a lipid lining that we might want to call a cell, though they would have been much smaller and many orders of magnatude less sophisticated. But it might have been a distant relative of the cell nucleus.

Many intermediate forms later, the duplication process got very sophisticated. Another layer of encapsulation has been added to readily store even more substances and catalysts. Many variations of cells have likely experimented with growing even larger but the thickness of the membrane necessary to contain that much mass wasn't effective. A few might have tried moving toward adding a third membrane but it added complexities that just didn't work.

A few of the cells got lucky and stumbled onto something that did work. They started collecting or synthesizing molecules that were sensitive to things like heat and light, and others found more ways to get information about their environment. Some would take in a sample from the outside world and bring it in for analysis.

Information about your environment is not much help if you can't do anything about it so response mechanisms were developed. These may have included propulsion and a way of releasing specific chemicals when they found themselves in a certain kind of enviroment.

When in the presence of other cells there would have been interesting releases of chemicals that triggered a counter-release, and so on. This could easily be considered the first communication. As time went on and complexity grew, these communications could come to include vibrations and discharges of light and heat. The sophistication of communication got to a level where other cells could be coordinated so that they actually worked with each other instead of against each other. Being in a crowded area still meant you had less of a stake in the food in area, but woking as a network took less effort to capture it. These were perhaps the first societies and made possible new biological forms like sponges.


And I think that is all for now. I may continue this later.. probably in another post.

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