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Member (Idle past 2963 days) Posts: 706 From: Joliet, il, USA Joined: |
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Author | Topic: Does the Darwinian theory require modification or replacement? | |||||||||||||||||||||||||||||||||||||||
Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
Wow, so Shapiro agrees with Shapiro as well, all we need now is Shapiro to agree and we'll have a universal scientific consensus.
TTFN, WK
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shadow71 Member (Idle past 2963 days) Posts: 706 From: Joliet, il, USA Joined: |
molbiogirl writes:
First, Cairns et al refuted directed mutation. I never claimed Cairns claimed directed mutation, I merely pointed out his paper casts doubts on the Luria & Delbeck expertiment allegedly showing random mutations. The only reason I mentioned Zheng, is that he said random mutations is a null hypotheisis, ie it may be the default hypothesis, but it is not proven.
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shadow71 Member (Idle past 2963 days) Posts: 706 From: Joliet, il, USA Joined: |
Shadow 71 writes:
I know Cairns and others have challenged the Luria & Delbuck experiment, but it this scientist is correct, we may have no proof of random mutations.
NoNukes writes:
Nice slight of hand. But your "this scientist" reference was to Zheng and his paper and not to Cairns and "Origin of Mutants" Dr. Adequate asked me to show where Carins disputed the Luria & Delbeck experiment, and I told him to read Carins paper "The Origins of mutants" for that information. I wasn't talking about Zheng in that reply.
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shadow71 Member (Idle past 2963 days) Posts: 706 From: Joliet, il, USA Joined: |
Wounded King writes:
Wow, so Shapiro agrees with Shapiro as well, all we need now is Shapiro to agree and we'll have a universal scientific consensus. I was pointing out there is authority for my assertions. Do you reject Shapiro out of hand?
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NoNukes Inactive Member |
shadow71 writes: molbiogirl writes:
First, Cairns et al refuted directed mutation. I never claimed Cairns claimed directed mutation, I merely pointed out his paper casts doubts on the Luria & Delbeck expertiment allegedly showing random mutations. Yes, Cairns 1988 paper did cast some doubt. And, as you also know, other experimenters pointed out potential errors in Cairns work shortly after the 1988 paper was published. But more importantly, in Cairns 1998 paper, the one quoted by molbiogirl, Cairn describes further research which removed the doubt cast by the 1988 paper. It is pointless to continue to cite Cairns "Origins of Mutations", at least for the purpose of casting doubt on Luria & Delbeck's experiment. Your nonsense regarding Zheng has been addressed elsewhere.
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NoNukes Inactive Member |
shadow71 writes: NoNukes writes:
Nice slight of hand. But your "this scientist" reference was to Zheng and his paper and not to Cairns and "Origin of Mutants" Dr. Adequate asked me to show where Carins disputed the Luria & Delbeck experiment, and I told him to read Carins paper "The Origins of mutants" for that information. I wasn't talking about Zheng in that reply. I accept that you did not mean to refer to Zheng in your reply, but Dr. Adequate certainly actually asked you to quote Zheng since you said that Zheng was the basis for your excitement. Here's what you said in Message 265 shadow71 writes: I have just been reading some papers on "directed mutations" and one very qualified researcher QI Zheng states as follows:
quote: That is an exciting event. So who is "this scientist" in your post. It's clearly Zheng and not Cairns. Whose work is featured in Message 265? So given your claim in Message 265, who do you expect Dr. Adequate was asking you to quote for the principle that there is no proof of random mutations in Message 270? Instead of speculating on what a null hypothesis might be and on what evidence for that null hypothesis there might have been in Zheng's paper based on reading a two line summary, Dr. Adequate asked you to cite Zheng actually saying that there was no proof of random mutation. The idea that you were being asked to cite Cairns for something you claimed to have gotten from Zheng is silly.
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Taq Member Posts: 10085 Joined: Member Rating: 5.1
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He claims he did.
No he didn't. Read it again: "where certain changes are non-random with respect to their potential biological utility." Potential biological utility is not fitness.
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Taq Member Posts: 10085 Joined: Member Rating: 5.1 |
I was pointing out there is authority for my assertions. In science, it is the data that matters, not authority.
Do you reject Shapiro out of hand? Do you accept Shapiro without understanding the data?
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NoNukes Inactive Member |
shadow71 writes: Here is a quote from Shapiro's review paper in 2010. Is he wrong in stating Darwin hypotheiszed random changes?
Shapiro writes:
In the 19th century, Darwin based his thinking on the observations of animal breeders and naturalists. Lacking detailed studies of inheritance, he postulated that change arose randomly as 'numerous, successive, slight variations' Shapiro overstates things a bit, and I believe you do as well.Hypothesized overstates Darwin's position and "postulated" is definitely incorrect for characterizing Darwin's position regarding random changes. Darwin's work does not depend on mutations being completely random. Speculated would be a more accurate characterization. Shapiro is closest to being correct when he talks about Darwin postulating 'numerous, successive, slight variations'. In chapter II of Origin of Species, we can understand that Darwin speculated on many sources of variation including Lamarkian variations. From Chapter II of Origin of Species
quote: In my view, it seems that Darwin speculated that some types of environment driven variations might be inherited. In other words, the ultimate source of variations might have been directed by the environment, random, or some combination, but in each case, variation would have still have plugged right into Darwin's theory of speciation. Darwin's focus was of course natural selection working on variations of whatever source to produce species. So yeah, Shapiro is wrong about Darwin. Edited by NoNukes, : fix some typos
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molbiogirl Member (Idle past 2671 days) Posts: 1909 From: MO Joined:
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I never claimed Cairns claimed directed mutation... Cairns' "challenge" to Luria & Delbeck WAS directed mutation.
These are the unexpected findings that led John Cairns and colleagues (10) to suggest that "bacteria, in stationary phase, have some way of producing (or selectively retaining) only the most appropriate mutations." 10. Cairns, J., J. Overbaugh, and S. Miller. 1988. The origin ofmutants. Nature (London) 335:142-145. Source. The title of his paper that followed his 1988 Origins of Mutants in 1992 is THE MECHANISMS OF DIRECTED MUTATION. Unfortunately for Cairns, a bunch of labs jumped on his directed mutation idea and tried to replicate it. And guess what?
The hypothesis did not fare well, however, for a number of reasons. First, several groups quickly proposed alternative explanations that could account for Cairns' data without requiring directed mutation [5]. Second, follow-up experiments that included additional controls, as well as more careful accounting of population dynamics, demonstrated that some studies supporting directed mutation were fatally flawed [6 and 7]. Third, no one could demonstrate a molecular mechanism for any case of directed mutation, despite numerous proposals, and some proposed mechanisms were tested and found wanting [7 and 8]. Source. And then guess what happened?Cairns had to walk back his directed mutation bullshit. Hence the quote I provided earlier. The only reason I mentioned Zheng, is that he said random mutations is a null hypotheisis, ie it may be the default hypothesis, but it is not proven. You continue to misunderstand null hypothesis. Would legalese help?
wiki writes: In most legal systems, the presumption that a defendant is innocent ("until proven guilty") can be interpreted as saying that his or her innocence is the null hypothesis. Would you say that when the null hypothesis is confirmed by a jury it has been proven? Look at it this way.The goal is to DISPROVE the null hypothesis (that the accused is innocent). If you do not DISPROVE the null hypothesis (convince the jury that the accused is guilty) then the null hypothesis (that the accused is innocent) is PROVEN. Zheng did not DISPROVE the null hypothesis; therefore, random mutation is PROVEN. Edited by molbiogirl, : No reason given. Edited by molbiogirl, : No reason given.
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AZPaul3 Member Posts: 8564 From: Phoenix Joined: Member Rating: 4.7 |
Reference my Message 296
shadow - Message 299 A null hypothesis is not a proven hypothesis.
shadow - Message 302 he said random mutations is a null hypotheisis, ie it may be the default hypothesis, but it is not proven.
I note you acknowledged my message 296. Then you continue with this same "Null hypothesis = not proven" BS. I must assume one of the following: 1. You acknowledged my message without reading it. 2. You read my message but did not comprehend its content. 3. You read and comprehended but choose to ignore its content. Which is it? I think this community deserves an answer so we know what kind of person we're dealing with here. Edited by AZPaul3, : mechanics. Mom whould really be PO'd if she saw that.
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molbiogirl Member (Idle past 2671 days) Posts: 1909 From: MO Joined: |
One more thought on your difficulty understanding the null hypothesis.
Would it help if Zheng used the word "proven"? Cause he did.
Thus, a mutation mediated by a newfound mechanism does not automatically qualify as a directed mutation, for the existence of an undocumented mutational mechanism itself is not a deviation from the random mutation hypothesis. However, if this mutation can be PROVEN to occur only under some specific environmental conditions that favor the survival of the resulting mutants, then that mutation can be a possible example of directed mutation. Emphasis added.
For instance, LENSKI et al. 1989 cited differential growth rates as a cause, which has been mathematically PROVEN (PAKES 1993 Down; ZHENG 2002). Source. FYI, Lenski was challenging Cairns' directed mutation bullshit.And it was mathematically proven.
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shadow71 Member (Idle past 2963 days) Posts: 706 From: Joliet, il, USA Joined: |
I read your message #296. When you use language such as "rectally ejected" I just refuse to reply to that type of nonsense.
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shadow71 Member (Idle past 2963 days) Posts: 706 From: Joliet, il, USA Joined: |
Taq writes:
No he didn't. Read it again: "where certain changes are non-random with respect to their potential biological utility." Potential biological utility is not fitness. MerriamWebster online dicitionary writes:
1utility noun \y-ˈti-lə-t\plural utilities Definition of UTILITY 1: fitness for some purpose or worth to some end 2: something useful or designed for use I interpret Shapiro as meaning fitness. If he did not mean random mutations for fitness, he would have just answered my question no.
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shadow71 Member (Idle past 2963 days) Posts: 706 From: Joliet, il, USA Joined: |
Taq writes:
In science, it is the data that matters, not authority. Do you accept Shapiro without understanding the data? I have told you many times that I do not know the data, or understand all of the data. I assume you and Shapiro understand the data and I rely on Shapiro's statements in papers as to what the data means.That is what I mean by authority. I am sure that if you publish papers you interpret what the data means and give your interpretation to your readers. Then your readers will be able to tell others what your position is based upon your interpretation of the data. Using your protocol, no lay person may read a scientific paper and comment on it.
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