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Member (Idle past 6724 days) Posts: 3085 From: Munich, Germany Joined: |
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Author | Topic: For Salty | |||||||||||||||||||||||||||
Mammuthus Member (Idle past 6724 days) Posts: 3085 From: Munich, Germany Joined: |
Salty writes:
I'm still game to take on the opposition. Anytime - anyplace. In the interest of not allowing salty to run around claiming he is unable to voice his opinions, I am starting this thread for salty to attempt (for the first time) to clarify his Semi-Meiotic hypothesis, demonstrate the data that supports it, debate (and I mean debate not just ignore questions and re-iterate refuted points) the mountains of evidence against it, and generally voice whatever opinion he wishes. I post it in the Free for All since none of the salty related subjects in the Evolution forum have stayed on topic for more than a few posts. Thus, in the Free for All we will be doing a "natural selection" experiment. If salty is able to debate his hypothesis in a compelling way, this thread should be lively. If not, it will fade away quickly, being too irrelevant to garner forum members attention....so, take it away salty...good luck. cheers,M
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Dr_Tazimus_maximus Member (Idle past 3466 days) Posts: 402 From: Gaithersburg, MD, USA Joined: |
First off, Mammuthus I think that this is a wonderful idea.
Now, as to the Clarification re: some of Dr. D.'s comments concerning the Semi-miotic hypothesis and the lack of evolution occuring in sexually reproducing species. How can the series of species radiations noted in the fossil record after each major exctinction event be explained if sexually reproducing species do not split and evolve into different species. I asked a varient this question earlier concerning the Cambrian explosion and your response was that you were not convinced species radiation occured within this group salties reply to my question re: speciation and the cambrian, actually my question was that as these species were likely sexually repoducing species then how did we get here from there. If you look ta the Permian or the K-T extinction boundries you see the same style of species radiation after the extinction event. So, how can this be explained if sexually reproducing species can only remove deleterious genes and not accumulate altered useful mutations which can include chromosomal re-arrangement. ------------------"Chance favors the prepared mind." L. Pasteur Taz [This message has been edited by Dr_Tazimus_maximus, 04-29-2003]
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Mammuthus Member (Idle past 6724 days) Posts: 3085 From: Munich, Germany Joined: |
Hi Taz,
I think there are more than a few of us who want clarification of his hypothesis and his evidence. In fairness to salty, he may not be aware of this thread (if he is even lurking on the forum at all). Could one of the Admin's let him know...then he can decide if he wants to participate. cheers,M
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derwood Member (Idle past 2125 days) Posts: 1457 Joined: |
I provided a short description of this 'hypothesis' of Davison's and he said that it was basically correct. It goes something like this:
An error occurs during Meiosis that results in a parthenogenic ovum.[how this would actually occur, salty does not say]. This parthenogenic ovum then if develops into a new species. That is, it is born (hatched, whatever), and it is totally different from its parent. It then reproduces asexually until a large enough popu- , er, um, pardon me - until there a whole bunchy ot htme, then, as if by magic, they start reproducing sexually, and this prevents them from changing any more. For this, the evidence provided in this forum by its primary proponant: Broom, Berg, etc. would havre agreed with him.... Evidence provided Davison's relevant papers: Sometimes turkeys can asexually reproduce... but the offspring are just turkeys... but a 'hopeful monster' could be in there somewhere! Broom, Berg, etc. would agree with him. "Darwinism" is dead. Did I miss anything?
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Mammuthus Member (Idle past 6724 days) Posts: 3085 From: Munich, Germany Joined: |
Hi Scott,
From his Manifesto this seems to be an accurate summary of salty's ideas. The first part of the manifesto largely says nothing as it is just a series of quotes mined from Broom, Berg, et al. with salty's comments about how badly "Darwinism" (which he never defines) explains evolution. When he gets into semi-meiosis it is clear he is trying to establish evolution via hopeful monsters but it is unclear how as you pointed out. One thing that occurred to me while reading it is he makes an artificial distinction between sexually and asexually reproducing organisms in that he seems to indicate that asexually reproducing cannot exchange genetic information. However, bacterial conjugation and other methods of horizontal transfer demonstrate that this is false. Even viruses exchange genetic information. Anyway, if you bump into salty in your forays onto other boards, please indicate to him that his hypothesis is still open for debate here if he wishes. cheers,M
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Dr_Tazimus_maximus Member (Idle past 3466 days) Posts: 402 From: Gaithersburg, MD, USA Joined: |
Not to mention that there is very little experimental support for asexual reproduction in many species (I am unaware of ANY in mammals, and I can not recall any in crustacians or reptiles either). While I agree that chromosomal re-arrangement plays a part in evolution, so does any other biologist/biochemist so this aspect of the semi-meitic proposal is not new. It is just not well defined due to the complexity and current lack of knowledge of the intricacies of the control of gene expression. Salty, or Dr. D., or whatever he prefers, also seems fixated on single point mutations as the primary mode of creative driving force (which he constantly confuses with selection as what the neo-darwinian camp views as the source of variation and new features in new species) while anyone well versed in molecular biology knows that amino acid changes via point mutation is only a small part of the possible genomic changes due to mutations. I have read the original articles concerning hopeful monsters and find useful data there, but I find that if you accept changes within the rate of evolution as possible that the concept fits in quite nicely with a larger darwinian framework, it just means that the changes are smaller than Goldschmidt proposed.
------------------"Chance favors the prepared mind." L. Pasteur Taz
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Quetzal Member (Idle past 6121 days) Posts: 3228 Joined: |
Just 'cause it's such a rare treat to be in a position to provide additional info to Dr. Taz, I'd like to quibble over the following:
Not to mention that there is very little experimental support for asexual reproduction in many species (I am unaware of ANY in mammals, and I can not recall any in crustacians or reptiles either).
I can't think of any asexual mammals, but there are a few exceptions to your statement. For instance, the southwestern whiptail lizard (Cnemidophorus velox) is a parthenogenetic reptile, and a whole slew of small crustaceans are either cyclical or obligate asexual reproducers, including several branchiopods (like Daphnia spp), copepods, and ostracods. Of course, there are also a bunch of fish (Poeciliopsis spp. minnows, Japanese carp Carassius auratus langsdorfii, etc) that are all female. One of the great things about evolution is that no matter what "rule" you apply, there will always be exceptions.
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Mammuthus Member (Idle past 6724 days) Posts: 3085 From: Munich, Germany Joined: |
Hi Taz,
I don't think it is a rate difference salty is arguing. As Scott pointed out, salty thinks the only way for a new species to arise is for a chromosomal rearrangement to occur during meiosis creating a new pre-adaptive phenotype (I assume he implies pre-adaptation given some of his posts regarding fish mutating and then discovering an environment they fit in) which must asexually reproduce until there are enough individuals around to resume sexual reproduction.Thus, at every branch in the primate tree, he would require sexual to asexual to sexual reproduction transitions. Regarding human evolution, he also claims that female humans are very capable of asexual reproduction (I will refrain from jokes about what his may imply for salty's sex life though I am finding it difficult ).
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derwood Member (Idle past 2125 days) Posts: 1457 Joined: |
quote: Indeed - there was a thread at Terry The Worm's place in which salty chimed in about Mary giving birth asexually... As far as bumping into salty, I doubt that will happen. I resigned form the Worm's in disgust at the idiocy and sycophantism displayed there, and that is the only place I have ever seen salty (besides here).
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Mammuthus Member (Idle past 6724 days) Posts: 3085 From: Munich, Germany Joined: |
Indeed - there was a thread at Terry The Worm's place in which salty chimed in about Mary giving birth asexually...
LOL!!!!!!!!!! Well, by his definition then, jesus was a new species...so salty will have some problems with the bible literalists on Terry's board... either that or the H in Jesus H christ stands for hermaphrodite since he would have had to mass produce himself until the new species was established and sexual reproduction could ensue...hard to test since the sole member of the new putative species was killed
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derwood Member (Idle past 2125 days) Posts: 1457 Joined: |
quote: A population of one....
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Mammuthus Member (Idle past 6724 days) Posts: 3085 From: Munich, Germany Joined: |
A population of one....
which is about the size of the population that accepts the semi-meoitic hypothesis.
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derwood Member (Idle past 2125 days) Posts: 1457 Joined: |
JA "If I ignore them, they don't exist" Davison up to his old antics at the Worm's den of idiots.
Incredible....
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crashfrog Member (Idle past 1716 days) Posts: 19762 From: Silver Spring, MD Joined: |
I love his summary dismissal of computer models. Could it be that he's just too old to trust computers?
Somebody who posts over there might mention the case where GP algorhythms created a radio circuit by accident when the designers were trying for an simple occilator... I don't have a reference; somebody else brough it up in an ID discussion here...
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Dr_Tazimus_maximus Member (Idle past 3466 days) Posts: 402 From: Gaithersburg, MD, USA Joined: |
Actually I think that Salty is back at the worms place because he was tired of having his proverbial intellectual head handed to him. I have noted that the worm stifles and bans anyone who places supporting data concerning evolution on his board. Just the place for a person who will not gather and display data supporting his position.
------------------"Chance favors the prepared mind." L. Pasteur Taz
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