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Author Topic:   Syamsu's objections to NS v.2
Wounded King
Member (Idle past 2926 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 1 of 2 (51331)
08-20-2003 6:37 AM


Having expressed disbelief at Peter for restarting this thread previously I now find myself doing the same thing. I think that Syamsus idea of looking at simulations of Natural Selection is an interesting way to go about things, although its actual relevance to the operation of NS in the real world can be argued.

As things stand Syamsu was handling a couple of lines of argument, one with Quetzal on the old topic of carrying capacity. My discussion was also touching peripherally on carrying capacity but was mostly focussed on showing syamsu published examples of computer simulations where differential reproductive success were a key component in the simulation. I gave a couple of examples and the one we ended up discussing was an Avida simulation of the development of complex characteristics. After complaining that the paper was interpretational and he really needed to see the code I gave Syamsu details of where he could find the code, he then came back and basically said that he didn't understand the code and couldn't tell whether the simulation had a comparative basis or not.

[This message has been edited by Wounded King, 08-21-2003]


Replies to this message:
 Message 2 by Wounded King, posted 08-21-2003 9:22 AM Wounded King has not yet responded

  
Wounded King
Member (Idle past 2926 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 2 of 2 (51484)
08-21-2003 9:22 AM
Reply to: Message 1 by Wounded King
08-20-2003 6:37 AM


Syamsu,

I don't know if you have seen this paper, I'd be interested to know what you think of it.

J Math Biol. 1996;34(5-6):511-32.

Darwinian adaptation, population genetics and the streetcar theory of evolution.

Hammerstein P.

This paper investigates the problem of how to conceive a robust theory of phenotypic adaptation in non-trivial models of evolutionary biology. A particular effort is made to develop a foundation of this theory in the context of n-locus population genetics. Therefore, the evolution of phenotypic traits is considered that are coded for by more than one gene. The potential for epistatic gene interactions is not a priori excluded. Furthermore, emphasis is laid on the intricacies of frequency-dependent selection. It is first discussed how strongly the scope for phenotypic adaptation is restricted by the complex nature of 'reproduction mechanics' in sexually reproducing diploid populations. This discussion shows that one can easily lose the traces of Darwinism in n-locus models of population genetics. In order to retrieve these traces, the outline of a new theory is given that I call 'streetcar theory of evolution'. This theory is based on the same models that geneticists have used in order to demonstrate substantial problems with the 'adaptationist programme'. However, these models are now analyzed differently by including thoughts about the evolutionary removal of genetic constraints. This requires consideration of a sufficiently wide range of potential mutant alleles and careful examination of what to consider as a stable state of the evolutionary process. A particular notion of stability is introduced in order to describe population states that are phenotypically stable against the effects of all mutant alleles that are to be expected in the long-run. Surprisingly, a long-term stable state can be characterized at the phenotypic level as a fitness maximum, a Nash equilibrium or an ESS. The paper presents these mathematical results and discusses - at unusual length for a mathematical journal - their fundamental role in our current understanding of evolution.

Another interesting paper is this one

Zoolog Sci. 2003;20(3):279-89.

Ecological aspects of the evolutionary processes.

Bock WJ.

Darwin in his On the Origin of species made it clear that evolutionary change depends on the combined action of two different causes, the first being the origin of genetically based phenotypic variation in the individual organisms comprising the population and the second being the action of selective agents of the external environment placing demands on the individual organisms. For over a century following Darwin, most evolutionists focused on the origin of inherited variation and its transmission; many workers continue to regard genetics to be the core of evolutionary theory. Far less attention has been given to the exact nature of the selective agents with most evolutionists still treating this cause imprecisely to the detriment of our understanding of both nomological and historical evolutionary theory. Darwin was vague in the meaning of his new concept of "Natural Selection," using it interchangeably as one of the causes for evolutionary change and as the final outcome (= evolutionary change). In 1930, natural selection was defined clearly as "non-random, differential reproduction of genes" by R. Fisher and J.B.S. Haldane which is a statement of the outcome of evolutionary process and which omits mention of the causes bringing about this change. Evolutionists quickly accepted this outcome definition of natural selection, and have used interchangeably selection both as a cause and as the result of evolutionary change, causing great confusion. Herein, the details will be discussed of how the external environment (i.e., the environment-phenotype interaction) serves as selective agents and exerts demands on the phenotypic organisms. Included are the concepts of fitness and of the components of fitness (= adaptations) which are respectively (a) survival, (b) direct reproductive and (c) indirect reproductive features. Finally, it will be argued that historical-narrative analyses of organisms, including classification and phylogenetic history, are possible only with a full understanding of nomological evolutionary theory and with functional/adaptive studies of the employed taxonomic features in addition to the standard comparative investigations.

Which deals in some depth with the various roles the environment plays in evolution and what we mean by 'natural selection'.

[This message has been edited by Wounded King, 08-21-2003]


This message is a reply to:
 Message 1 by Wounded King, posted 08-20-2003 6:37 AM Wounded King has not yet responded

  
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