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Author Topic:   Asexual to sexual reproduction? How?
timothy44
Inactive Member


Message 48 of 78 (368653)
12-09-2006 1:59 PM


Evolutionists can't explain Origin of Gender and Sexual Reproduction
In their article entitled The Origin of Gender and Sexual Production the authors Bert Thompson, Ph.D. and Brad Harrub, Ph.D. wrote the following:
quote:
"In his book, The Masterpiece of Nature: The Evolution of Genetics and Sexuality, Graham Bell described the dilemma in the following manner:
”Sex is the queen of problems in evolutionary biology. Perhaps no other natural phenomenon has aroused so much interest; certainly none has sowed as much confusion. The insights of Darwin and Mendel, which have illuminated so many mysteries, have so far failed to shed more than a dim and wavering light on the central mystery of sexuality, emphasizing its obscurity by its very isolation.’[1]
The same year that Bell released his book, well-known evolutionist Philip Kitcher noted: “Despite some ingenious suggestions by orthodox Darwinians, there is no convincing Darwinian history for the emergence of sexual reproduction.”[2] Evolutionists since have freely admitted that the origin of gender and sexual reproduction still remains one of the most difficult problems in biology (see, for example, Maynard-Smith, 1986, p. 35)....
When pressed to answer questions such as, “Where did males and females actually come from?,” “What is the evolutionary origin of sex?,” evolutionists become silent. How could nature evolve a female member of a species that produces eggs and is internally equipped to nourish a growing embryo, while at the same time evolving a male member that produces motile sperm cells? And, further, how is it that these gametes (eggs and sperm) conveniently “evolved” so that they each contain half the normal chromosome number of somatic (body) cells? [Somatic cells reproduce via the process of mitosis, which maintains the species’ standard chromosome number; gametes are produced via the process of meiosis, which halves that number. We will have more to say about both processes later.]....
It is the complexity of this process, and the manner in which it is copied from generation to generation, which practically drove Mark Ridley to distraction in The Cooperative Gene.
”No one in human culture would try the trick of first making two copies of a message, then breaking each into short bits at random, combining equal amounts from the two to form the version to be transmitted, and throwing the unused half away. You only have to think of sex to see how absurd it is. The “sexual” method of reading a book would be to buy two copies, rip the pages out, and make a new copy by combining half the pages from one and half from the other, tossing a coin at each page to decide which original to take the page from and which to throw away’[32]
Again, from an evolutionary viewpoint, sex would be considered “absurd.” But from a design viewpoint, it is nothing short of incredible!"
Secondly, creationists Jonathon Safarti and Michael Matthews wrote:
quote:
"Creationists can explain the origin of fully functioning sexual reproduction, from the start, in an optimal and genetically diverse population. Once the mechanisms are already in place, they have these advantages. But simply having advantages doesn’t remotely explain how they could be built from scratch. The hypothetical transitional forms would be highly disadvantageous, so natural selection would work against them. In many cases, the male and female genitalia are precisely tuned so one could fit the other, meaning that they could not have evolved independently."
The evolutionist apologetic website TalkOrigins.org poorly attempts to defend the evolutionary position regarding the origin of gender and sexual reproduction by stating the following:
quote:
"The variety of life cycles is very great. It is not simply a matter of being sexual or asexual. There are many intermediate stages. A gradual origin, with each step favored by natural selection, is possible.(Kondrashov 1997). The earliest steps involve single-celled organisms exchanging genetic information; they need not be distinct sexes."
The creationist apologetic website CreationWiki responds to TalkOrigins.org by responding:
quote:
"As is so often the case, Talk Origins misses the point. The problem with an evolutionary origin of sexual reproduction is not so much the lack of a path, but that mutation and natural selection are incapable of doing the job. An evolutionary origin of sexual reproduction requires the development of two totally different but mutually compatible systems of organs; this multiplies the potential problems and increases the likelihood of failure.
Also, the Talk Origins article overstates what the Kondrashov article actually stated. Here is what the Kondrashov article abstract states:
"The life cycles of cellular species are reviewed from the genetic perspective. Almost all life cycles include stages during which only one genome is transmitted from a parent to its offspring. This, together with interorganismal gene exchange, which occurs regularly in at least some prokaryotes and in the majority of eukaryotes, allows selection to evaluate different alleles more or less independently. Regular genetic changes due to intraorganismal ploidy cycles or recombination may also be important in life cycles of many unicellular forms. Eukaryotic amphimixis is generally similar in all taxa, but the current data on the phylogeny and reproduction of unicellular eukaryotes are insufficient to determine whether it evolved several times or just once. Theoretically , gradual origin of amphimixis from apomixis, with each step favored by natural selection, is feasible. However, we still do not know how this process occurred nor what selection caused it. For reasons not entirely clear, some properties of amphimictic life cycles are much less variable and more conservative than the others. Evolution of many aspects of reproduction requires more theoretical studies, while the existing data are insufficient to choose among the currently competing hypotheses. (emphasis added)[1]"
(regarding the abstract quote above: "Amphimixis is another term for sexual reproduction, generally by the fusion of a male and female gamete and subsequent recombination. The opposite of amphimixis is apomixis: asexual (clonal) reproduction." [2] )
There is a difference between possible and theoretically feasible. Furthermore, the abstract adds some scholarly caution in that it states "we still do not know how this process occurred nor what selection caused it" and also adds that the evolutionists are currently choosing between competing hypothesis."
The evolutionist apologetic website TalkOrigins also defends the evolutionary position quite poorly by stating:
quote:
"Males and females most emphatically would not evolve independently. Sex, by definition, depends on both male and female acting together. As sex evolved, there would have been some incompatibilities causing sterility (just as there are today), but these would affect individuals, not whole populations, and the genes that cause such incompatibility would rapidly be selected against."
CreationWiki.org effectively responds by stating:
quote:
1. Brown did not say that “Males and females would have to evolve independently,” what he did say was that the “complementary reproductive systems of the male and female must have completely and independently evolved at each stage at about the same time and place.” The point is that both systems would have had to evolve without mutual influence.
2.Talk Origins claim, that Males and females must have evolved together because sexual reproduction requires both, is circular reasoning. It is true that for them to evolve they would have to evolve together, but this is Brown’s point, since getting 2 complex but mutually compatible systems to evolve step by step and side by side is incredibly small.
3. The fact that any incompatibility would be selected against, would also tend to prevent any significant change that could lead to sexual reproduction, unless it occurred nearly perfectly in both systems.
Lastly, I would ask the evolutionists this question which a friend of mine posed to an evolutionist: The human female reproductive mechanism uses scent. The mechanism gives a scent that only attracts the sperm cells that it was designed to attract. How could this mechanism evolve step-by-step?
References
CreationWiki ,(Talk.Origins) Sex can't have evolved at: Sex can't have evolved (Talk.Origins) - CreationWiki, the encyclopedia of creation science
Jonathon Safarti and Michael Matthews, Argument: Evolution of sex at: Design in Nature | Answers in Genesis
Bert Thompson, Ph.D. and Brad Harrub, Ph.D. , The Origin of Gender and Sexual Reproduction at http://www.apologeticspress.org/articles/136

Replies to this message:
 Message 49 by AdminNosy, posted 12-09-2006 2:12 PM timothy44 has replied

  
timothy44
Inactive Member


Message 50 of 78 (368662)
12-09-2006 2:37 PM
Reply to: Message 49 by AdminNosy
12-09-2006 2:12 PM


Re: Be sure to read and debate in good faith
I thought BertThompson, PHD made some points that the evolutionists at this forum did not address. For example, the Thompson quote states and pay close attention to the bolded portions:
quote:
The same year that Bell released his book, well-known evolutionist Philip Kitcher noted: “Despite some ingenious suggestions by orthodox Darwinians, there is no convincing Darwinian history for the emergence of sexual reproduction.”[2] Evolutionists since have freely admitted that the origin of gender and sexual reproduction still remains one of the most difficult problems in biology (see, for example, Maynard-Smith, 1986, p. 35)....
When pressed to answer questions such as, “Where did males and females actually come from?,” “What is the evolutionary origin of sex?,” evolutionists become silent. How could nature evolve a female member of a species that produces eggs and is internally equipped to nourish a growing embryo, while at the same time evolving a male member that produces motile sperm cells? And, further, how is it that these gametes (eggs and sperm) conveniently “evolved” so that they each contain half the normal chromosome number of somatic (body) cells? [Somatic cells reproduce via the process of mitosis, which maintains the species’ standard chromosome number; gametes are produced via the process of meiosis, which halves that number. We will have more to say about both processes later.]....
It is the complexity of this process, and the manner in which it is copied from generation to generation, which practically drove Mark Ridley to distraction in The Cooperative Gene.
”No one in human culture would try the trick of first making two copies of a message, then breaking each into short bits at random, combining equal amounts from the two to form the version to be transmitted, and throwing the unused half away. You only have to think of sex to see how absurd it is. The “sexual” method of reading a book would be to buy two copies, rip the pages out, and make a new copy by combining half the pages from one and half from the other, tossing a coin at each page to decide which original to take the page from and which to throw away’[32]

Also, even a proevolutionary position science journal article was forced to admit:
quote:
Theoretically , gradual origin of amphimixis from apomixis, with each step favored by natural selection, is feasible. However, we still do not know how this process occurred nor what selection caused it. For reasons not entirely clear, some properties of amphimictic life cycles are much less variable and more conservative than the others. Evolution of many aspects of reproduction requires more theoretical studies, while the existing data are insufficient to choose among the currently competing hypotheses. (emphasis added)[1]"
Lastly, I thought this question posed to evolutionists was very relevant:
Lastly, I would ask the evolutionists this question which a friend of mine posed to an evolutionist: The human female reproductive mechanism uses scent. The mechanism gives a scent that only attracts the sperm cells that it was designed to attract. How could this mechanism evolve step-by-step?
Edited by timothy44, : No reason given.
Edited by timothy44, : No reason given.

This message is a reply to:
 Message 49 by AdminNosy, posted 12-09-2006 2:12 PM AdminNosy has not replied

Replies to this message:
 Message 51 by Chiroptera, posted 12-09-2006 3:00 PM timothy44 has replied
 Message 55 by platypus, posted 12-09-2006 3:34 PM timothy44 has not replied

  
timothy44
Inactive Member


Message 52 of 78 (368675)
12-09-2006 3:12 PM
Reply to: Message 51 by Chiroptera
12-09-2006 3:00 PM


Re: Be sure to read and debate in good faith
Chiroptera,
You wrote:
quote:
What was unconvincing about L-man's explanation?
For one, I don't believe he adequetly addressed the following by Dr. Thompson:
quote:
How could nature evolve a female member of a species that produces eggs and is internally equipped to nourish a growing embryo, while at the same time evolving a male member that produces motile sperm cells? And, further, how is it that these gametes (eggs and sperm) conveniently “evolved” so that they each contain half the normal chromosome number of somatic (body) cells? [Somatic cells reproduce via the process of mitosis, which maintains the species’ standard chromosome number; gametes are produced via the process of meiosis, which halves that number. We will have more to say about both processes later.]....
It is the complexity of this process, and the manner in which it is copied from generation to generation, which practically drove Mark Ridley to distraction in The Cooperative Gene.
”No one in human culture would try the trick of first making two copies of a message, then breaking each into short bits at random, combining equal amounts from the two to form the version to be transmitted, and throwing the unused half away. You only have to think of sex to see how absurd it is. The “sexual” method of reading a book would be to buy two copies, rip the pages out, and make a new copy by combining half the pages from one and half from the other, tossing a coin at each page to decide which original to take the page from and which to throw away’[32]
Secondly, I don't think he adequately adressed CreationWiki's objections.

This message is a reply to:
 Message 51 by Chiroptera, posted 12-09-2006 3:00 PM Chiroptera has replied

Replies to this message:
 Message 53 by Chiroptera, posted 12-09-2006 3:20 PM timothy44 has replied

  
timothy44
Inactive Member


Message 54 of 78 (368679)
12-09-2006 3:28 PM
Reply to: Message 53 by Chiroptera
12-09-2006 3:20 PM


Re: Be sure to read and debate in good faith
Chiroptera,
You wrote:
quote:
I don't understand the CreationWiki quote.
What is it that you don't understand about the CreationWiki quotes I cited in my post?

This message is a reply to:
 Message 53 by Chiroptera, posted 12-09-2006 3:20 PM Chiroptera has replied

Replies to this message:
 Message 56 by Chiroptera, posted 12-09-2006 3:40 PM timothy44 has replied

  
timothy44
Inactive Member


Message 57 of 78 (368686)
12-09-2006 3:59 PM
Reply to: Message 56 by Chiroptera
12-09-2006 3:40 PM


Re: Be sure to read and debate in good faith
CreationWiki doesn't admit the validity of that quote. It merely states that TalkOrigins did not adequetly represent what the article actually stated as can be seen by the abstract.
Now please address the other CreationWiki material I cited.

This message is a reply to:
 Message 56 by Chiroptera, posted 12-09-2006 3:40 PM Chiroptera has replied

Replies to this message:
 Message 58 by Chiroptera, posted 12-09-2006 4:07 PM timothy44 has replied

  
timothy44
Inactive Member


Message 59 of 78 (368692)
12-09-2006 4:25 PM
Reply to: Message 58 by Chiroptera
12-09-2006 4:07 PM


Re: Be sure to read and debate in good faith
Chiroptera,
I can see you really don't want to address the CreationWiki material. No need to carry on our "dialogue".
Edited by timothy44, : No reason given.

This message is a reply to:
 Message 58 by Chiroptera, posted 12-09-2006 4:07 PM Chiroptera has replied

Replies to this message:
 Message 61 by Chiroptera, posted 12-09-2006 4:37 PM timothy44 has not replied
 Message 66 by AdminNosy, posted 12-09-2006 8:41 PM timothy44 has not replied

  
timothy44
Inactive Member


Message 60 of 78 (368693)
12-09-2006 4:26 PM
Reply to: Message 58 by Chiroptera
12-09-2006 4:07 PM


Re: Be sure to read and debate in good faith
double post
Edited by timothy44, : No reason given.

This message is a reply to:
 Message 58 by Chiroptera, posted 12-09-2006 4:07 PM Chiroptera has not replied

  
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