General Theory of Evolution

Dear all,It is good to see that all the evo's are so united on this 'excellent post'. However, and I presume you already expected this, I completely disagree with this outdated overview. Dear evo's this is the 21st century.I presume you expect me to reiterate my arguments against natural selection on the genomic level, but I won't. Why, because you are able to find my comments on genetic redundancies on this site, and why they cannot be explained by natural selection. On the other hand, they are explained by the multipurpose genome that holds that the major part of the genes of any organism are redundant. This has been scientifically proven over the last decade. The hypothesis of a multipurpose genome in conjunction with (non)-random mutation not only explains genetic redundancies but is also able to explain ALL evolutionary observations. And that is what it is all about in science. To explain observations.However, regarding natural selction...THE MAIN FUNCTION OF NATURAL SELECTION IS NOT TO CREATE BUT TO REMOVE.In contrast to what Darwin thought (selection of the most adapted, fittest or whatever he called it), "The weaker are selected against". Pretty obvious in nature isn't it? In effecto, the genepool of the multipurpose genome doesn't deteriorate to rapidly.This has been known for a long time, but it is simply ignored to keep the hype alive. (For refernces see: L.Spetner, Not By Chance, chapter 7.)For the rest, Fred made some excellent remarks.best wishes,
Peter

Dear percy,You write:
"Evolutionary solutions to competitive pressures can represent either increasing or decreasing complexity. For example, the cheetah migrates into a new habitat putting the local gazelles under competitive pressure to become more evasive. Most solutions will involve increased complexity. Increased speed would usually mean increased complexity because the gazelle would need improved coordination at the higher speed, improved musculature, better delivery of blood supply to muscles, improved lung capacity, better hoof architecture, and so forth. Evolution of the horns to better fight off the cheetah would not only involve changes to horns, but also to the neck muscles, the skeletal arrangement of the upper spine to better support charging, improved coordination again, and so forth. Many of the solutions will involve increased complexity.But increased complexity is not the only path to improved survival. Getting smaller to better hide in the tall grass is also possible and might involve decreased complexity. Certainly cave fish, which once had sight but lost it, are examples of decreasing complexity.So, both increasing and decreasing complexity are possible with evolution, but increasing complexity seems to more often provide the necessary survival improvement. It is for this reason that the fossil record is one of generally increasing complexity, and not because of any inherently progressive property of evolution.I rewrite:
"BIOLOGICAL solutions to competitive pressures can represent either NO increasing or decreasing complexity DUE TO A MULTI PURPOSE GENOME THAT ALLOWS ORGANISMS TO RESPOND RAPIDLY TO CHANGING ENVIRONMENTS. For example, the cheetah migrates into a new habitat putting the local gazelles under competitive pressure to become more evasive. THE solutions involves NO INCREASE IN complexity, BUT THE SHUFFLING AND ACTIVATION OF PREEXISTING (REDUNDANT) GENES. Increased speed would usually mean increased complexity because the gazelle would need improved coordination at the higher speed, SO THE PREEXISTING PATHWAYS IN THE MOTORCORTEX ARE ADJUSTED JUST AS NEEDED. THE SAME ACCOUNTS FOR improved musculature, better delivery of blood supply to muscles, improved lung capacity, better hoof architecture, and so forth. ADAPTATIONS of the horns to better fight off the cheetah would not only involve MODIFICATIONS OF PREEXISTING REGULATORY PROGRAMS to horns, but also to the neck muscles, the skeletal arrangement of the upper spine to better support charging, improved coordination again, and so forth. The solutions will NOT involve increased complexity.SINCE ALL INFORMATION IS PRESENT IN THE MULTIPURPOSE GENOME, increased complexity is not REQUIRED to improved survival. Getting smaller to better hide in the tall grass is also possible THROUGH DIFFERENTIAL REGULATION OF GROWTH FACTORS and might involve decreased OR NO EFFECT ON complexity AT ALL. Certainly cave fish, which once had sight but lost it, are examples of decreasing complexity DUE TO LOSS OF GENES OR DIFFERENTIAL GENE EXPRESSION.So, NO increase in complexity IS REQUIRED and decreasing complexity IS possible with A MULTI PURPOSE GENOME, but THE EXTANT complexity IN THE MULTIPURPOSE GENOME seems to more often provide the necessary survival improvement. It is for THE reason OF CREATONS IN A MORPHOGENETIC FIELD that the fossil record is one of generally increasing complexity, and not because of any inherently progressive property of THE ONCE VERY POPULAR THEORY OF evolution, THAT IN OUR 21st CENTURY VISION SEEMS A BIT UNREALISTIC.Best wishes,
PETER[This message has been edited by peter borger, 09-27-2002]

Dear Quetzal,You write:
"This is something of a mis-statement. A change in the selection pressures in a given organism's environment don't cause the organism to change. This is the fallacy of "upward" or progressive evolution you keep talking about. Selection pressures on a population tend to favor the survival of individuals with certain characteristics, primarily be weeding out those individuals who don't have those characteristics. Eventually, the "favored" characteristics will come to predominate in the population. To use your own example, the introduction of cheetahs into an environment where gazelles have never faced cheetah predation will not cause anything like an "upward pressure" forcing gazelles to get more evasive. What happens is the "slow" gazelles get eaten, the "fast" (comparatively) survive at least long enough to reproduce. Therefore, "fast" traits get passed down to the next generation.I say:
Exactly my point. The DNA of the fast animals is already in the genepool of the multipurpose genome. A bit of shuffling, a bit of (non-)random mutations and voila a "new" faster population after a couple of generations! New genes? NO. Different organisation? Maybe. Distinct gene regulation? Sure.Remember the old joke about the two guys being chased by the bear: "Why are you putting on tennis shoes? You can't outrun a bear.", one says. The other responds, "I don't have to outrun the bear. I only have to outrun you." Natural selection works to favor the guy with tennis shoes... "Yes, I remember. It was a joke, wasn't it? And that is why everyone is wearing Nikes, nowadays?Best wishes,
Peter[This message has been edited by peter borger, 09-27-2002]

Dear Syamsa,Although your remarks are interesting, I have a few comments.You say:
To simplify matters, I will anchor the understanding of the nature of reproduction in the observation of the most simple organism, the DNA molecule. Not only does the DNA molecule function in the development of traits, but it can also reproduce itself independent of any trait. When DNA is put on a feedingdish, without a cell, without a body to carry it, it is still capable to use the resources on the dish to assemble copies of itself.I say:
This is not entirely true. To make copies of DNA it always needs pylomerases (proteins) and you have to add them to the medium. So, the DNA molecule needs at least one trait. In living cells the DNA molecule specifies these polymereases and are induced only during cellgrowth. Considering the halflife of proteins --and thus polymerases-- one always has to replenish wornout polymerases from external. So, the DNA molecule does not replicate by itself, it requires polymerases.And you say:
And so are the newly assembled copies of DNA able to make copies of themselves from the resources on the dish. The ability of the copies to also make copies results in the number of DNA molecules to increase faster and faster. The resources on the dish will become scarce leading to competition for resources for reproduction. Some DNA might get tangled up leading to changes in the stucture of the DNA molecule. A small example of descent with modification, or evolution.I say:
Experiments like this have been carried out with RNA's of different lengths and RNA polymerases in the lab under limiting conditions and it turned out that there is selection. After several selective cycles the SHORTER RNA molecules increase, since they are able to replicate faster. Ultimately the shortest RNA survived.
Similarly, DNA in an organism that is not under selective constraint will easily be lost.Best wishes,
Peter

dear Syamsu,You say:
"I didn't know this, but still I consider proteins a resource, and not a trait, because that is consistent with how those words are most commonly defined as far as I know.I say:
DNA specifies --among other things-- proteins and thus they are traits as well. How are these things commonly defined then?You say:
Also someone told me that it was proven on the molecular level that the assembly of DNA follows from the action of the DNA molecule, and not from the action of the resources on the DNA.I say:
Probably this someone meant the hybridisation of two complementary DNA strands. They indeed hybridise to from the double DNA helix. The duplication of one strand to yield the complementary strand needs DNA-specified enzymes, and something to prime.You say:
Selection of "naked" RNA, I was looking for something like that, thanks for your comments.I say:
No worries.Best wishes,
Peter