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Author
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Topic: Speciation
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nosivad
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Member # 767
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posted 10. May 2004 05:38
Sure. Darwin's finches demonstrate far less variation than Canis familiaris. Furthermore, the 94 paper by the Grants shows hybridization without loss of fitness between forms previously (and probably still) regarded as species. The acid test of hybrid fertility is of course difficult, but not impossible, to apply with birds. If the neoDarwinians are so confdent of evolution in the finches they would perform the necessary experiments to verify it. Dobzhansky's criteria are unambiguous. I am also anxious to find someone who would be willing to perform a reciprocal cross between a Great Dane and a Chihuahua. I bet it would succeed in both directions and produce fertile offspring, just as did the documented case I mentioned in the Manifesto involving a female Dachshund and a male St Bernard. The fact that the neoDarwinians stopped testing their hypothesis is the most telling demonstration of their insecurity. The Grant's come along with real observations and their conclusions seem to be swept under the rug. I have not kept up with the literature on Darwin's finches as I have more important things to consider. However, I did reference the 94 paper by the Grant's in the Manifesto.
[ 10. May 2004, 06:26: Message edited by: nosivad ]
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peter borger
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posted 10. May 2004 07:24
Annual beaksize variations in Darwins finches might as well be RNAi mediated. Why not study the mechanisms instead of phenomenology?
peebee
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nosivad
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posted 10. May 2004 10:24
The Darwinians don't need to do experiments as they are convinced they already have the answers. I can't recall a single published experimental test of artificial selection since Dobzhansky's failed attempt years ago with Drosophila. Of course Luther Burbank knew from a lifetime of personal experience that selection would never produce a new species. He even ventured to set the limits on what was possible. I remain convinced that sexually reproducing creatures are essentially immutable which is a primary reason for their rampant extinction as their recent history so dramatically indicates. The sexual (Darwinian and Mendelian) model is a failure. It is time to try something new. Fortunately it is already happening.
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warren_bergerson
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Member # 262
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posted 10. May 2004 11:06
Rex has presented what he describes as predictions based on evolutionary theory. It should be noted that if these are real predictions, and not just after the fact interpretations of the data or judgmental speculation, demonstrating that the predictions are not valid would not falsify evolutionary theory. Darwinian theory could easily be reconciled to a very diverse set of possible findings relating to the speciation process.
At least on the surface, Darwinian theory and speciation has stopped would appear to be very different and completely incompatible hypotheses. Yet despite the very large body of evidence that exists on the subject of speciation, there does not appear to be any evidence that clearly demonstrates that one hypothesis or type of hypothesis is correct and the other is clearly wrong. [Individuals may interpret or judge the evidence to be more supportive of one type of hypotheses than the other, but those are subjective opinions not objective scientific conclusions.]
There are, I believe, predictions such as correctly predicting processes that will produce artificial speciation, that could produce objective scientific evidence supporting one type of hypotheses and rejecting the other. However, neither type of hypotheses appears to have produced a specific speciation prediction that produces a practical test.
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nosivad
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posted 10. May 2004 13:14
Warren
The test is right there before us and always has been. Can experimental selection result in speciation? I say it can't and until it can be demonstrated, there is only one proper conclusion. Contemporary species are immutable beyond the level of variety. There is nothing at all vague or mysterious about it whatsoever. I say - get cracking Darwinians. Produce or abandon your hypothesis. This, like all other challenges to the Darwinian position will be ignored. I have offered other challenges to the neoDarwinians not one of which has even been acknowledged. I'm getting used to it.
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warren_bergerson
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posted 10. May 2004 14:34
John,
IMO, the inability to produce testable speciation predictions is as much a problem for your type of hypotheses as it is for the neo-Darwinian type hypotheses. Asserting that a competing hypotheses needs to make successful predictions is not the same as making your hypotheses predictive.
Both your hypotheses and the neo-Darwinian hypotheses might have difficulty with ‘speciation due in part to non-genetic factors’ test. If speciation is due entirely to genetic changes, then transplanting embryos between species should always result in the production of healthy offspring.
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Janitor@MIT
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Member # 125
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posted 10. May 2004 14:54
Is sex “Mendelian”? Was Mendel wrong?!
On first impression Mendelism is based axiomatically upon discrete “factors,” that are positively (non-randomly) assortively recombined (differentiated then integrated). If that is the basis of Mendelian genetics, then it has become increasingly apparent that “molecular genetics” is non-Mendelian, or at best “quasi-Mendelian.”
We note the historical resistance of the Neo-Darwinians (in particular Mayr and Simpson) to the theoretical developments of molecular biology and in particular molecular genetics, and often casually assume (the historians do, "we") it was because of general philosophical and methodological conflicts, differences in “perspective”—certainly not because molecular genetics challenged the great achievement of the Neo-Darwinists’, the synthesis of Darwin and Mendel (a significant issue in their day). I.e., we think that molecular biology was objectionable by directly questioning Darwin (i.e., the Neo-Darwinists) certainly not Mendel!
Is molecular genetics “Mendelian”? Maybe, almost, not quite, inexactly?... And if even so, what difference does it make? I mean, Mendel based his theory of “genetics” upon direct observation. (As opposed to Darwin who just adopted what the sophists dreamt.) So molecular genetics must result in Mendelian genetics (?).
Just how far does Mendel go? Will he go as far (with us) as evolutionary theory requires? Or will Mendel, like Darwin, be left behind?
(Am I outrageous, or what?! Is it unthinakble? Nonsensical?)
[Edited to correct the "ebonics." No slur intended. I just wasn't sure that everyone understood "ebonics."]
Just found this:
http://146.186.95.23/weiss_lab/C&Q/C&Q3_mendelsgarden.pdf
LOL Just to be fair to Fisher, here is his (extraodinary) paper:
http://www.library.adelaide.edu.au/digitised/fisher/144.pdf
[ 10. May 2004, 17:54: Message edited by: Janitor@MIT ]
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nosivad
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posted 10. May 2004 17:41
Mendelian genetics is the genetics associated with sexual reproduction. I am convinced there is another kind of genetics which is a latent genetic expression which can be released (derepressed) by the restructuring of the chromosome. This genetic expression is not revealed by the segregation and recombination characteristic of Mendelian inheritance. This is what I mean by the Prescribed Evolutionary hypothesis which is intimately related to the Semi-meiotic hypothesis. These two hypotheses assume that there was no need to introduce new information during evolution; instead evolution has been an emergent phenomenon involving the ordered release of preformed developmental information. I have arrived at this position by the elimination of Lamarckian and Darwinian explanations as each being without experimental verification. I see no other alternative. I hope this clarifies my characterization of Mendelian genetics as being the genetics associated with sexual reproduction.
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Rex Kerr
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Member # 632
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posted 11. May 2004 04:21
I'd propose ways to induce speciation, but I'm wary of people saying that "that's cheating" because I'd propose doing things that weren't really natural in order to speed up the process.
Instead, I think it's better to look for the signature of speciation methods predicted by Darwinian methods. E.g., in very recent species that have formed allopatrically, there should be evidence of a recent population bottleneck (which can be found, for instance, by looking at SNP diversity); in very recent species that have formed sympatrically, there should be very strong assortive mating (a behavioral phenotype) even in the absence of (or perhaps especially in the absence of) factors causing hybrid sterility. There are a variety of places to look for these signatures, assuming that habitat destruction doesn't wipe them out first. (The cichlids in Lake Victoria were nearly ideal, but they're in grave danger now due to overfishing, competition from introduced species, poor water quality, etc..)
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nosivad
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posted 11. May 2004 08:09
How can the alteration of the habitat destroy organisms that are capable of evolutionary change? Shouldn't they be responding to such alterations? Where are those responses? These are the questions I have asked and to which no answers have been provided. I was compelled to draw the only reasonable conclusion - obligatory sexual reproduction is not a competent evolutionary device. I wrote a paper about it.
The "blind alley". Its significance for evolutionary theory. Rivista di Biologia 86: 101-111, 1993.
In it I specifically identified sexual reproduction as the "blind alley". An online version of that paper is available at my home page. www.uvm.edu/~jdavison
Nothing has transpired in the last eleven years to change my opinion. Quite the contrary, time has strengthened it.
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warren_bergerson
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posted 11. May 2004 08:21
Janitor brings up what I think is a good point. If you compare our current knowledge of genetics to Mendelian concepts, there is only a quasi-fit. The same is true for Darwin and neo-Darwin concepts. In a broad informal sense, Mendel, Darwin, and neo-Darwin are compatible with current knowledge. In a narrower more formal sense, there are many aspects of current knowledge that go beyond the Mendel, Darwin, and neo-Darwin.
If you hope to resolve questions such as “Are Medelian, Darwinian, and neo-Darwinian theories still valid or do they need to be replaced?” you must first define the criteria to be used for rejecting and replacing scientific theories. If you use the ‘can be reconciled to observed facts’ criteria or the ‘acceptable to recognized authorities’ criteria, then, IMO, you are likely to conclude that Medelian, Darwinian, and neo-Darwinian theories are still ‘valid’.
If you use the ‘produces testable predictions which can successfully pass independent testing’ criteria, then, again IMO, Mendel, Darwin, and neo-Darwin, if they ever satisfied the requirements for scientific theories, certainly do not meet the criteria today.
Speciation provides, IMO, a clear example of a situation where it should be possible to formulate hypotheses that produce testable predictions. Species exist and can be observed. We should be able to explain based on observations why two groups of organisms can not successfully interbreed, and we should be able to predict what conditions are required to produce the required ‘species boundary’.
Have either traditional biology or John Davison produced speciation hypotheses that produce predictions that can be independently tested? The problem, I suggest, is with the type of hypotheses being considered. Traditional (and non-traditional) biology are looking for mechanistic type models of speciation. As Rex’s comments suggest, it may very well be possible to predict one or more methods that will artificially produce new species. However, it is also likely that the artificially produced/predicted species will involve processes and mechanisms that do not occur in nature. [This is not unlike the situation where flying behavior is produced using propellers and locomotion is produced using wheels.]
Species boundaries speciation, are abstract concepts and causal paradigms, not specific mechanisms produced by specific mechanistic processes. In order to generate predictive speciation hypotheses, you need to first recognize a new type of predictive hypotheses. Predictive hypotheses based on the concept of ‘behaviors controlled by goal directed intelligence’ will, I suggest, work.
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nosivad
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posted 11. May 2004 10:56
My Semi-meiotic hypothesis is obviously testable. The issue is why isn't it being tested. All that is required, and this is admittedly quite a bit, is to have female organisms that are known to carry one or more chromosomal rearrangements in heterozygous form, and who also produce oocytes that can experimentally be subject to inhibition of the second meiotic division following activation of the egg either by irradiated sperm or by some other agency that will activate the egg without contributing genetic information. The vertebrate ovum is ideally suited for this acid test as, at the moment it is ovulated, it has completed the first meiotic division and is arrested, typically in metaphase of the second meiotic division. This is apparently a universal feature of vertebrate oogenesis. Not only is the egg waiting for the sperm, it is also waiting for an experimental verification of the semi-meiotic hypothesis. It does not surprise me that the evolutionary establishment, dominated as it is by Darwinians, is not interested in pursung this line of research. It is capable, in a single stroke, of destroying the entire fabric of the neoDarwinian hypothesis. It is also potentially capable of supporting the Prescribed Evolutionary Hypothesis. Darwinians don't even test their own hypothesis any more for reasons that require no further explanation from me. In short, Darwinism is not an experimental science and, with its insistence on gradualism, never was.
"If you tell the truth, you can be certain, sooner or later to be found out."
Oscar Wilde
[ 11. May 2004, 16:11: Message edited by: nosivad ]
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Rex Kerr
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posted 11. May 2004 19:09
quote:
How can the alteration of the habitat destroy organisms that are capable of evolutionary change? Shouldn't they be responding to such alterations?
Not if the change is too rapid. It takes time to generate appropriate diversity, and if the species does not already have sufficient variation to be essentially pre-adapted to the environmental conditions, then it will simply go extinct.
In fact, this is a good argument against rapid, single-step, intelligent changes. There is no such speed limitation in a planned semi-meiotic hypothesis, and yet extinction is common when conditions change rapidly.
quote:
Have either traditional biology or John Davison produced speciation hypotheses that produce predictions that can be independently tested?
What do you think my previous posts were about? It's really not worth posting when everything I type goes in one eye and out the other.
[ 11. May 2004, 19:13: Message edited by: Rex Kerr ]
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Janitor@MIT
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posted 11. May 2004 19:42
It does not take "time." It is a (complicated)function of effective population size, which is determinative of the "pre-adapted" state of the population. Evolutionary biology is a very highly statistical science, but we are often very selective of the statistics we use and how we interpret them. Every population will explore all possible adaptive avenues (open or acessible to it), even if the outcome of any path explored is inviable. Why? Because God was stupid when he designed life! LOL
Is there the thought here that the population should be considered stationary and that selection moves it around like the master moves his chess pieces? Gee, that sounds so familiar. Where have i heard that idea before?...
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Rex Kerr
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posted 11. May 2004 23:26
It does take time, but it does not take only time.
However, Davison apparently is working under the assumption that it doesn't take time. My comment was meant only to correct that mistake, not imply that population size, mutation rate, diversity of ecosystem, etc., aren't also important factors.
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