Originally posted by Helen:
Ah, all is sweetness and light on the western front...
Ah, long time no see! Hope you're feeling better . .
Mark, evolutionists are at a total loss when it comes to really explaining the so-called evolution of sex. They can get as far as bacteria swapping some genetic material, but that is a FAR cry from a multicellular organism having only half the necessary chromosomes in its sex cells and the means wherewith to combine with the opposite sex to produce a viable cell with a full complement of genetic material!
It really doesn't matter to us Theistic evolutionists whether or not it is completely a natural phenomenon for the evolutionary path to develop chromosones and sex or whether it took God's intervention.
Here are some quotes from Michal and Levin's The Evolution of Sex (1988) -- a compilation of material on this subject published by Sinaur Associates, Inc.
A survey of evolution biologists would doubtless come up with a consensus that the elucidaton of the selective pressures responsible for the origin and maintenance of sex is a "big" (maybe the "biggest") unsolved problem in evolutionary biology...there is no consensus about where its solution lies...no clear solution emerges. [p. vii]
We have here the classic Helenistic Quote mining. Helen searches far and wide for whatever lines she can find that supports her idea of the moment and quotes it as if nothing else exists in the realm of human thought. Here she finds a biologist who is willing to express his ignorance on the benefits of sex for the organism and assumes all the rest of science is equally ignorant. And note the date. Not the latest word, to be sure!
...the costs of sex to the individual are usually high and these costs are unlikely to be compensated for by benefits to the species...the costs of sex are explicit and borne by individual organisms, while the postulated benefits of sex have been vague and not readily modeled. The crises involving the question of sex can be seen clearly in this contrast between the costs and benefits of sex. [p. 2]
Modelling of the benefits of sex has become easier since 1988, we all know about the explosion of computer availability since that time. My advice to all the readers of this material is to disregard anything about the benefits and cost of sexual selection that does not take the insights of computer modelling into account.
Contrary to an earlier statement in this thread that sex encourages evolution by producing diversity, although diversity is expressed within the limits of the existing genome, evolution is hindered by sex.
Here we have a recurring theme of Helen's to the effect that there are fixed limits to diversity that keep species within their "kinds". There is no biological evidence for any such limit.
We also have the raw statement that evolution is "hindered" by sex, but no mention of how it does this hindering.
The combining and recombining of sexual material generation by generation tends to produce stability in a population, and not change. Mutations are usually quickly weeded out.
That would, of course, be HARMFUL mutations, not the beneficial ones. Sexual recombination favors the weeding out of HARMFUL mutations. It does this by swapping more of them into some unfortunate individuals and less of them into more fortunate individuals, and then the selection process of life does its thing.
Nor is there ANY evidence in any sexually reproducing organism of any mutation building on another mutation to produce any change in form or function. And evolution depends on this!
There's lots of evidence for just that, but Helen ignores it.
Please note the following from Sex and Evolution by G.C. Williams, 1975, Princeton University Press:
Please note again how far back in time she has to go to find this stuff
The primary task for anyone wishing to show favorable selection of sex is to find a previously unsuspected 50% advantage to balance the 50% cost of meiosis. Anyone familiar with accepted evolutionary thought will realize wht an unlikely sort of quest this is.
If you are stuck with a bad mutation, a 50% chance of getting rid of it in your offspring might be a good thing, don't you suppose?
We know that a net selective disadvantage of 1% would cause a gene to be lost rapidly in most populations, and sex has a known disadvantage of 50%. The problem has been examined by some of the most distinguished of evolutionary theorists, but they have either failed to find any reproductive advantage in sexual reproduction, or have merely showed the formal possibility of weak advantages that would probably not be adequate to balance even modest recombinational load. Nothing remotely aproaching an advantage that could balance the cost of meiosis has been suggested. The impossibility of sex being an immediate reproductive adaptation in higher organisms would seem to be as firmly established a conclusion as can be found in current evoutionary thought. Yet this conclusion must surely be wrong. All around us are plant and animal populations with both asexual and sexual reproduction.
Since the computer simulations have shown it works out ok, nobody is complaining like this any more. This material is all way out of date.
And N

NE has even the slightest clue how on earth any organism managed to develop the ability to produce cells with only half the genetic complement along with the necessary equipment for exchange, so that some organism of the same type, but a different sex, who also managed to develop a cell with half the complement, was able to be produced.
Incremental steps, one at a time, of course. Genetic swapping first. Then elimination of risk elements, making it safe. Then isolation of genetic components to make them the only things swapped. Bundling of components as part of that. The tighter the bundling, the closer we get to having chromosones. Swapping itself would be incrementally proceding from a random process to more and better controls. An accidental doubling of the bundle/chromosone sets the stage for sending over one while keeping the other.
There, that wasn't so hard, was it? The point being, incremental stages are certainly possible all up and down the line.
Mark, they are blowing dust all over the place and simply declaring it happened. It couldn't and it didn't.
It DID happen, so it must have had SOME WAY to happen. If it is truly physically impossible, then perhaps God intervened with a miracle to help the process of evolution along. Who are we to tell Him what to do? But I have faith that God is smart enough to design the whole thing into the laws of nature. Surely none of us thinks that would be above and beyond the ability of God, do we? Ah, I thought not.