|
Author
|
Topic: Fernando Castro-Chavez: Some Implications for the Study of Intelligent Design ...
|
Fernando Castro-Chavez
Member
Member # 1201
|
posted 04. April 2004 01:50
Pim:
Key fragment of the Letters of Mendel to Nägeli:
Letter VIII
Of the experiments of previous years, those dealing with Matthiola annua and glabra, Zea, and Mirabilis were concluded last year. Their hybrids behave exactly like those of Pisum. Darwin’s statements concerning hybrids of the genera mentioned in “the variation of animals and plants under domestication,” based on reports of others, need to be corrected in many respects.
Your devoted,
GR. MENDEL
Brünn, 3 July 1870
------------------------
In the early 1860s, Mendel sent his paper to Nägeli who was the nearest of the prominent botanists of the time. Nägeli glanced through the paper but apparently was repelled by the mathematics. He himself was a biologist of the old school and indulged in rather windy and obscure theorizations. A paper by an unknown monk with no theories but with only painstaking countings and ratios seemed worthless to him. He returned it with brief and cold comments, and this effectively chilled Mendel. To be sure, Nägeli offered to grow some of Mendel's seeds, but he never did and the offer was probably not meant seriously. He did not answer Mendel's later letters, and when Nägeli wrote his major work on evolution twenty years later, he did not mention Mendel.
Nägeli's cold reception had undoubtedly disheartened Mendel as did the indifference of the naturalists in Brünn. Nägeli died in 1891, never dreaming what a terrible mistake he had made... several nineteenth-century evolutionists such as Huxley and Nägeli had suggested evolution by jumps, but without evidence [somewhat like the proposals of N. Eldedgre and S.J. Gould].
http://www.rit.edu/~flwstv/genetics.html
------------------------
Karl Wilhelm Von Nägeli, a Swiss botanist, suggested in print that evolution occurred as a series of jumps. Nägeli went so far as to say that there was a drive within a species for these jumps to keep it varying in the same direction... His concept was ‘biological inertia’ and Nägeli called it "orthogenesis."
Mendel wrote up his results and sent them to Nägeli. Nägeli was not impressed because he thought that Mendel was just counting plants instead of working on some fundamental new scheme like his own orthogenesis. Bad break, for Mendel’s theory was of fundamental importance, while Nägeli’s was worthless. But Nägeli had the reputation, Mendel did not. Mendel's work remained unknown and he himself un-honored.
http://epswww.unm.edu/facstaff/zsharp/106/lecture%208,%20mendel.htm
------------------------
Mendel asked one of his fellow monks to send forty special reprints to botanists and other distinguished scientific figures known to be interested in the hybridization of plants. Nine of these reprints have so far come to light. One of the recipients was Carl Wilhelm von Nägeli, probably the most highly acclaimed botanist of the mid-nineteenth century, who was then teaching in Munich. He was the only one of the forty who was prompted to embark on an extended correspondence with Mendel. However, it appears likely that Nägeli had only glanced at the reprint because — although it in fact dealt with no fewer than 355 cross-bred strains and 12,980 resultant hybrids — he described Mendel’s work as "incomplete" and urged him to carry on with his experiments. Nägeli also offered Mendel "fatal" advice: to continue his investigations using the hawkweed (Hieracium), a plant belonging to the family of the asters. It was only later that botanists discovered these plants’ asexual reproduction, which meant that experiments in hybridization with hawkweed were bound to be inconclusive, since the genetic information is transferred exclusively via the maternal line.
http://hjem.get2net.dk/Paleontology/text/mreflect.html
------------------------
The arduous experiments required the use of a microscope, mirrors, fine needles, and artificial light and caused such severe eyestrain and backaches that Mendel was obliged to interrupt his research for long periods of time.
http://astro4.ast.vill.edu/mendel/gregor.htm
------------------------
Carl Nägeli, the botanist to whom Mendel wrote to about his pea plant experiments, was no longer lecturing at Münich. Nägeli, however, knew Correns' parents and took an interest in him. Nägeli was the one who encouraged Correns' interest in botany and advised Correns on his thesis subject. Nägeli and Correns' connection was more than just scientific; Correns eventually married Nägeli's grandniece.
http://www.dnaftb.org/dnaftb/concept_6/con6bio.html
------------------------
Karl von Nägeli, of the University of Munich, had previously experimented with hawkweed, a plant that follows a very unusual reproductive pattern. Mendel started experimenting with hawkweed, and lost confidence in everything he had accomplished studying peas. He finally gave up all experimentation when he became abbot of the monastery, though he continued to dabble in ornamental horticulture.
It's naive to say that Mendel was just a humble monk who never hoped for fame. In fact, he did hope for recognition, but the only recognition that came during his lifetime was as a local meteorologist. He died never knowing how much his findings would change history. Mendel's work was cited in a few papers in the late 19th century, but it wasn't until the dawning of the 20th, motivated in part by a priority dispute about publication, that other scientists took note of the 19th-century genius.
http://www.strangescience.net/mendel.htm
------------------------
Nägeli, Karl von (1817-1891)
He did more harm to biology than good, especially in his contemptuous dismissal of Mendel's work on pea plants.
http://scienceworld.wolfram.com/biography/Naegeli.html
------------------------
More fragments of the Letters of Mendel to Nägeli:
I
I am afraid that in the course of my experiments, especially with Hieracium, I shall encounter many difficulties, and therefore I am turning confidently to your honor with the request that you not deny me your esteemed interest when I need your advice.
With the greatest esteem and respect for your honor, I subscribe myself,
GREGOR MENDEL
Monastery Capitular and Teacher in the High School.
Brünn, 31 December 1866
II
With respect to the essay which your honor had the kindness to accept, I think I should add the following information: the experiments which are discussed were conducted from 1856 to 1863. I knew that the results I obtained were not easily compatible with our contemporary scientific knowledge, and that under the circumstances publication of one such isolated experiment was doubly dangerous; dangerous for the experimenter and for the cause he represented. Thus I made every effort to verify, with other plants, the results obtained with Pisum.
Your devoted,
G. MENDEL
(AltBrünn, Monastery of St. Thomas)
Brünn, 18 April, 1867
V
HIGHLY ESTEEMED SIR:
Accept my most cordial gratitude for the Hieracium seeds, which arrived in good condition. How grateful I am for this kind shipment, and how much I do appreciate your kindness in promising also a shipment of living plants. I shall do my utmost to produce all the possible hybrids among the species, and if they should be fertile, their progeny will be observed for several generations. I must ask you to please charge the expenses of purchase and transportation, and any others, to my account.
Your devoted friend,
GREGOR MENDEL
Abbot and Prelate of the
Monastery of St. Thomas
Brünn, 4 May 1868
VI
HIGHLY ESTEEMED FRIEND:
Forgive me for being so tardy in expressing my most sincere gratitude for the species of Hieracium which you sent me. I received the little box on May 12. Since I had to start a long tour of inspection on the same day, I could not find the time necessary to thank you in writing. The gardener received instructions to handle the plants with great care, to pot one specimen of each, and plant the rest in the garden.
When I returned a few days ago, I found to my great regret, that half of the potted plants had died, probably the consequence of excessive watering.
Your devoted friend,
GREGOR MENDEL
Brünn, 12 June 1868
VII
Hybrids of Hieracium show, strangely enough, a very different behavior in the production of their progeny, than do those of Cirsium. Cirsium would be an excellent experimental plant for the study of variable hybrids, if it required less space.
Yours always respectfully,
GREGOR MENDEL
Brünn, 15 April 1869
VIII
In Pisum and other plant genera I had observed only uniform hybrids and therefore expected the same in Hieracium. I must admit to you, honored friend, how greatly I was deceived in this respect.
On this occasion I cannot resist remarking how striking it is that the hybrids of Hieracium show a behavior exactly opposite to those of Pisum. Evidently we are here dealing only with individual phenomena...
Your devoted,
GR. MENDEL
Brünn, 3 July 1870
X
The exception which Hieracium seems to make in this respect must find a natural explanation...
I cannot yet give a report on the success of the collection of Moravian hybrids of Hieracium initiated by Prof. Niessl. Shipments from the corresponding members of our society are expected not sooner than this winter.
Yours very respectfully,
GR. MENDEL
Brünn 18/11 1873
http://www.esp.org/foundations/genetics/classical/holdings/m/gm-let.pdf
------------------------
There is the neglect of Mendel's accomplishments during his lifetime and the futility of his years of writing to Nägeli.
http://www.mendelweb.org/archive/MWhartl.txt
IP: Logged
|
|
Pim van Meurs
Member
Member # 541
|
posted 04. April 2004 16:53
Chavez on the history of Mendel and Nagel writes:
He (Nagel) did more harm to biology than good, especially in his contemptuous dismissal of Mendel's work on pea plants.
What seems to be the issue is a scientific disagreement followed by Mendel accepting the use of an organism which did not sexual reproduce, making it appear that Mendel's claims were indeed fallacious.
Chavez may have missed my relevant quote to this extent
quote:
Between 1866-1873 Mendel corresponded with Carl Nägeli (1817-91), Professor of Botany at the University of Munich and an authority in plant hybrids. Nägeli was convinced that hybrids were generally unstable and he could not agree with Mendel's theory that the characters passed onto hybrids from their parents were constant. The period of Mendel's correspondence with Nägeli [i] coincides with the experiments with the Hieracium which disappointingly seemed to prove Nägeli right. Mendel's observed what he called "a peculiar behaviour of the hybrids" which he was unable to explain - i.e. that the Hieracium exhibited both sexual and a-sexual reproduction (a phenomenon known as apomixis).
Should Nagel be held responsible for Mendel experimenting with the Hieracium which appeared to prove Nagel correct?
Seems that history has more to say here. Nagel supported Mendel's research with Hieracium
quote:
All these results were never published by MENDEL. They are preserved in the correspondence with C. v. NÄGELI. C.CORRENS edited and published it in 1905. Supported by C. v. NÄGELI MENDEL did also work on Hieracium hybrids, especially such of the subgenera Pilosella and Archhieracium. The choice of these objects proved to be rather unhappy, since Hieracium is a genus that poses difficulties to botanists even today. Often stable transitional forms occur, whose existence MENDEL could not explain. Besides the technical problems (flowers of composites are never easy to work with) were his experiments disturbed by a phenomenon that was not understood until much later: The seeds of several species develop directly from the mother cells of the embryo sac or a cell of the surrounding tissue, meiosis does not take place. Such a way of seed development is called agamospermy. The mother plant develops seeds without being pollinated. These seeds behave like layers of the mother plant. Additionally species exist, where part of the seeds develop from agamospermy and part from pollinated egg cells. This leads to completely confusing ratios, because the preconditions upon which MENDEL's laws are founded are not fulfilled any more.
and
quote:
Nägeli also offered Mendel "fatal" advice: to continue his investigations using the hawkweed (Hieracium), a plant belonging to the family of the asters. It was only later that botanists discovered these plants’ asexual reproduction, which meant that experiments in hybridisation with hawkweed were bound to be inconclusive, since the genetic information is transferred exclusively via the maternal
IP: Logged
|
|
Pim van Meurs
Member
Member # 541
|
posted 04. April 2004 16:55
Chavez: Presently I am interpreting my research results with Intelligent Design in mind.
What exactly does that mean? Practically and theoretically?
IP: Logged
|
|
Mesk
Member
Member # 630
|
posted 04. April 2004 23:02
quote:
nobody:
That depends on how reliable genetic clocks actually are:
"Clocks tick at different rates in different lineages and at different times. And new work on the biology of mitochondria suggests that their evolution may be more complicated than researchers had suspected."
(Strauss, Evelyn; "Can Mitochondrial Clocks Keep Time?" Science, 283:1435, 1999.)
This is a perfectly valid point for estimating divergence dates between different species, and the article that Fernando cites makes this point very clearly indeed (anyone who has not read the Graur and Martin paper should do so - it is fascinating and remarkably entertaining to watch the authors utterly shred the claims of several researchers who should have known better.) Molecular clocks are always problematic, but the issues are far less serious when one is examining time-scales within a single species, as is the case for human genetic studies. In that case, one can use very straightforward population genetics calculations to estimate the age of specific mutations, using parameters which can either be directly observed or inferred with a high degree of confidence. Most of these calculations should be fairly non-controversial even for creationists, since they do not involve the assumption of common descent but rather rely on simple, robust and well-validated models of molecular evolution within populations.
The results of studies using these methods have been quite unambiguous - many parts of the human genome are ancient, displaying patterns of variation that must have accumulated over hundreds of thousands (and sometimes millions) of years. Large genetic studies generate impressively information-rich data sets, allowing researchers to estimate these ages using several different independent techniques (for instance, the number of variable sites, the profile of allele frequencies, and the extent of linkage between variable sites can each be used separately to estimate divergence times). No matter how desperately you tweak the parameters, there is absolutely no way to fit the observed depth of human genetic history into a meagre ten thousand years.
quote:
nobody:
What I have noticed over the years is that evolutionists sometimes extrapolate wildly without gathering enough information.
This is certainly true on occasion (the recent Nature article on the possible evolutionary significance of the MYH16 null mutation in humans is a good example). But evolutionists are definitely not alone in this. Fernando's selective discussion of human genetic history is a classic example: from a few anomalous dates (most of which come from techniques which are known to be relatively inaccurate), and ignoring the vast bulk of the literature which contradicts these dates, he speculates that humans are less than ten thousand years old. This is not good science; and when good science is done on human genetic history, the results invariably contradict Fernando's claims.
Mesk.
IP: Logged
|
|
Scott
Member
Member # 1222
|
posted 05. April 2004 00:31
quote:
...anyone who has not read the Graur and Martin paper should do so...
Here's the PubMed link.
Scott
[ 05. April 2004, 00:32: Message edited by: Scott ]
IP: Logged
|
|
Rex Kerr
Member
Member # 632
|
posted 05. April 2004 02:00
That's an awesome paper.
Annoying, no doubt, to the people who forgot to do proper error analysis, but maybe they'll be more careful next time.
IP: Logged
|
|
gordon
Member
Member # 781
|
posted 05. April 2004 08:14
I have seen the Graur and Martin paper cited on a couple of evolution-unfriendly boards now, as was done here and at ARN as some sort of broad-based condemnation of molecular clock analyses and by 'unwritten implication' a condemnation of evolution as a whole.
That is fallacious on the face of it, and if one bothers to read the paper - and better yet, some of the papers that get 'shredded'- one sees something different than what is implied.
I recently lead a discussion on this very topic using the G and M paper as a focal point(I must say I was tickled to find G and M 'misquote' one of the dates from one of their targeted papers - a minor tangent but one that got some chuckles from the discussion participants).
A few things that seem to slip below the radar on this - the rather 'unprofessional' tone of the paper indicates to me that there is more going on than some concerns about the science of the Blair/Hedges/Kumar group. A rivalry perhaps?
I read a couple of the lambasted papers and it seemed to me that the 'attacked' authors covered their bases fairly well. Certainly, if one is going to perform statistical analyses, they should be done properly and of course when they are not, they deserve criticism.
And again, the 'attack' was directed at a specific group of individuals who had published several papers on related topics; it was not a broad analysis of all molecular clock studies or methods, and it was, after all, an 'Opinion' paper.
I also noticed that Hedges et al. have already written a response, the abstract of which was, as of a few days ago, available via Biomednet.
So, while to "meat" of the criticisms have applicablity - not just to molecular clock analyses, but all scientific endeavors - the use of that paper as a "See, I told you evolution is all washed up" buttress is not only improper, it is quite unsupportable as such.
IP: Logged
|
|
gordon
Member
Member # 781
|
posted 05. April 2004 08:29
double post
[ 05. April 2004, 08:43: Message edited by: gordon ]
IP: Logged
|
|
charlie d.
Member
Member # 159
|
posted 05. April 2004 15:05
The issues discussed in Graur's and Martin's critique of Hedges & C are far from black-and-white. Certainly those who claim that that review invalidates molecular clock analysis wholesale have either not read it, or not understood it, or pretend not to. Anyway, here is Hedges' and Kumar's reply, with a related editorial, both forthcoming in TiG. Good reading.
[ 05. April 2004, 15:07: Message edited by: charlie d. ]
IP: Logged
|
|
Fernando Castro-Chavez
Member
Member # 1201
|
posted 06. April 2004 00:53
Pim:
From your previous links related to Mendel and his Advisor the next are some important excerpts:
"Nägeli was convinced that hybrids were generally unstable and he could not agree with Mendel's theory that the characters passed onto hybrids from their parents were constant." "Hieracium is a genus that poses difficulties to botanists even today." "Nägeli also offered Mendel "fatal" advice: to continue his investigations using the hawkweed (Hieracium), a plant belonging to the family of the asters."
Also, the key historical moments from the links that I quoted are:
Mendel wrote to his Advisor that "Matthiola annua and glabra, Zea, and Mirabilis were concluded last year. Their hybrids behave exactly like those of Pisum."
But his Advisor did not put any care on that statement.
"Nägeli offered to grow some of Mendel's seeds, but he never did and the offer was probably not meant seriously. He did not answer Mendel's later letters, and when Nägeli wrote his major work on evolution twenty years later, he did not mention Mendel."
Mendel's Advisor did not took any care or interest in corroborating Mendel's seeds of Pisum, nor in answering the last letters of Mendel, and the worst was that Nägeli prevented the work of Mendel to be known because he did not even mention Mendel's work in his own works. Nägeli dismissed it. However, Nägeli imposed that only if the hawkweed behaved like Pisum, he will start paying any attention to Mendel's basic discovery, dismissing all the other species that Mendel was mentioning (plus Salix, Cirsium, etc.)
"It appears likely that Nägeli had only glanced at the reprint because — although it in fact dealt with no fewer than 355 cross-bred strains and 12,980 resultant hybrids — he described Mendel’s work as "incomplete" and urged him to carry on with his experiments."
Plus, other sites affirm that Nägeli's copy of the work of Mendel was not even completely unwrapped and cut, showing that he did not even took any care on doing a carefully review of the whole work.
"He (Nägeli) did more harm to biology than good, especially in his contemptuous dismissal of Mendel's work on pea plants."
I converge with them, however I did not originated that statement, the team that designs the Software "Mathematica" did it, as the link posted in the quotation that you refer demonstrates. They also showed me that Nägeli was an Evolutionsit but not a Darwinist, as Nägeli himself rejected the main proposals of Darwin, trying to develop his own theory of Evolution, which resembled the one developed a century later by Gould. That evidence demonstrates that there wasn’t then and there is not now any unified theory of evolution but rather, as “Nobody” wisely had said before, multiple hypotheses on “evolution.”
----------
Precision of molecular time estimates
S. Blair Hedges and Sudhir Kumar
(Online: 24 March 2004.)
End of their own Abstract: "Molecular clocks have great potential but must be calibrated carefully."
However, even the most "careful calibration" is subject to the subjective and fallible estimates of "the calibrator", and never is going to be accepted as "absolute", especially if contradicts other important fields of Research. My most recent and ongoing work has not yet been submitted. I must not disclose it until then.
IP: Logged
|
|
Rex Kerr
Member
Member # 632
|
posted 06. April 2004 02:27
quote:
Even the most "careful calibration" is subject to the subjective and fallible estimates of "the calibrator"
The same could be said for measuring the speed of light, but we seem to have pretty good agreement on that one to at least six significant digits.
Molecular clocks tend to agree with other age estimates to at least within an order of magnitude, so they're unlikely to be completely wrong or drastically at odds with other research. (Especially when proper error estimates are made.)
IP: Logged
|
|
charlie d.
Member
Member # 159
|
posted 06. April 2004 12:23
quote:
Precision of molecular time estimates
S. Blair Hedges and Sudhir Kumar
(Online: 24 March 2004.)
End of their own Abstract: "Molecular clocks have great potential but must be calibrated carefully."
However, even the most "careful calibration" is subject to the subjective and fallible estimates of "the calibrator", and never is going to be accepted as "absolute", especially if contradicts other important fields of Research. My most recent and ongoing work has not yet been submitted. I must not disclose it until then.
Fernando, you may want to read past the abstract. Of course, Hedges and Kumar argue that they didcalibrate their clock carefully, and, although I am far from being an expert, I think they make a decent argument for themselves (especially in the face of Graur's and Martin's scathing criticism).
I also have no idea what "other important fields of Research" molecular clock data supposedly contradict - you may want to elaborate. Hedge's type of studies (using molecular clocks for deep-time resolution) are at the very reaches of the methodology (that's why his work is considered pioneering), but most molecular clock analyses are within restricted and quite homogeneous clades, and are generally extremely reproducible and well supported by independent evidence. Quite simply, none of the recent criticisms of Hedge's work would apply to, say, molecular clock estimates of primate species divergence.
IP: Logged
|
|
Fernando Castro-Chavez
Member
Member # 1201
|
posted 07. April 2004 17:02
Taking one step further the study of “The Natural Limits to Biological Change” we can say that the concept of “Species” is fallible only because of the human ignorance. I.E., a simple and very old condition for the definition of living animals as ‘Kinds’ or ‘Species’ is:
" A fertile group of organisms capable to provide a fertile lineage."
It demands field observations, and/or laboratory, i.e. genetic experimentation to determine securely whether inter-breeding is possible or not. The time, effort and money needed to delimit Species here is vital. Physiological incapabilities (proposed by Dobzhansky) and reproductive isolation (proposed by Mayr) are not sufficient to define "Species", as a female Chihuahua and a male Great Dane are physiologically incapable to mate but are certainly and accurately members of the same ‘Specie’, or the fifteen isolated subspecies of the Galapagos tortoises certainly correspond to the same ‘Specie’, living today near extinction in at least ten separate islands reproductively isolated one from the others.
If you can review all the articles published or to be published in relation to the evolutionary claim of ‘Speciation’ you can clearly see that all of them are based on speculation. ‘Speciation’ is only present in the imagination of its writer, observer or experimenter.
Even the finches on the Galapagos and on any other different habitat are able to mate and to produce fertile young, showing conclusively that there are not different species of finches but merely varieties of the same species. Finches mate naturally, as studies by Peter and Rosemary Grant have proved. Here once more, the fallibility on using the concept of ‘Species’ is due to human ignorance (check there the word ‘interbreed’):
http://www.carlzimmer.com/articles/2002/articles_2002_Finch.html
http://www.pnas.org/cgi/content/full/94/15/7768
http://www.probe.org/docs/galapagos.html
Evolutionary thinking attempts to confuse uninformed readers with their presuppositions and their inaccurate ‘basic definitions.’
The definition of ‘Species’ for plants (and for yeasts and insects, also) must be expanded to include within them their natural ability to develop polyploidy. Nothing is “evolving” here but a natural Law of polyploidy is being exerted.
On reviewing the 'Observed Instances of Speciation' present in the evolutionarily oriented board 'Talk Origins' (endorsed by Joseph Boxhorn); Richard Milton provides the next keen observations:
Every one of the next examples is a case of polyploidy. None of them has any relevance to the kind of adaptive genetic mutations that evolutionists claim ‘can’ or ‘may’ occur:
Polyploidy, Hybridization or Hybridization Followed by Polyploidization:
Evening Primrose (Oenothera gigas)
Kew Primrose (Primula kewensis)
Trapopogonan
Raphanobrassica
Hemp Nettle (Galeopsis tetrahit)
Madia citrigracilis
Brassica
Maidenhair Fern (Adiantum pedatum)
Woodsia Fern (Woodsia abbeae)
Neither valid to support ‘Speciation’ are the instances of ‘almost complete reproductive isolation.’ Joseph Boxhorn is also wrongly saying that ‘a low tolerance variety is a different species from a high tolerance variety’ of the same Specie M. guttatus.
Joseph Boxhorn (and with him all the ‘evolutionary’ community) says that two fruit flies, which he asserts, are different species, successfully mate and produce offspring (thereby proving conclusively that they are not different species but the same species.) He calls the offspring 'hybrids' in an attempt to smuggle their 'different' species status in by the back door. Later, some of the Drosophila offspring exhibit 'behavioral isolation' (like Chihuahuas and Great Danes), but this is irrelevant as a sign of species status. So where, in all this, is there an instance of speciation -- or one species turning into another?
The same objection applies to every experiment relying on tests of ‘voluntary behavior’ (assortative mating) rather than real science (such as artificial insemination). 'Ambiguous' examples of ‘Speciation’ are not ambiguous at all -- like everything else in the ‘Speciation’ research, they are emphatically not examples of ‘Speciation’ but of ‘Speculation’.
Virtually all the so-called examples of speciation (one species turning into another species) offered by evolutionists are in reality examples of them exploiting the ambiguity of a weak definition of species. Evolutionists suggest that, what are no more than subspecific varieties, are actually different species. Even the most enthusiastic evolutionist would not try to suggest that the process of polyploidy can be cited as the engine of evolution, and would acknowledge that it is incapable of producing anything other than a big version of the same organism (even if E. S. Lander is ‘pushing’ it).
"Speciation" in the evolutionist sense of one species gradually changing by selection into another has not been observed and no examples are known.
The appearance of disease-resistant strains in microorganisms is exactly the same phenomenon as 'industrial melanism' in moths. That strain already exists from the outset, and is nothing more than a subspecific variety of the species in question. Nothing new is coming into being.
Richard Milton concludes his observations by saying that ‘Talk Origins’ (and I must add that all evolutionary literature) is ‘a misleading discussion', as seen here regarding 'Speciation.'
There is not a single real case of observed evolutionary 'Speciation'.
"Most frequently the false identification of species status through semantic ruses such as whether or not fruit flies choose of their own volition to mate even when they are genetically identical. In the fossil record, the commonest error is to bestow different 'species' status on different fossils without being able to apply any real species test, and without having a complete chain of physical evidence linking them."
"Speciation remains a hypothetical mechanism, not so far observed or demonstrated either in the fossil record or in the living world."
Evolutionism "is nothing more than a theory, lacking experimental confirmation and supported by nothing more than weak circumstantial evidence."
To read it in Richard Milton’s words:
http://www.alternativescience.com/talk-origins-speciations.htm , http://www.alternativescience.com/speciation.htm
More recent references on ‘Speciation’ can show the truth of ‘Speciation’ as being a complete Speculation, done under an ambiguous use of the word ‘Specie’ and so, being deceptive. References provided in:
http://www.iscid.org/boards/ubb-get_topic-f-18-t-000034.html
[ 08. April 2004, 10:29: Message edited by: Fernando Castro-Chavez ]
IP: Logged
|
|
nobody
Member
Member # 145
|
posted 07. April 2004 18:11
I need to look into this topic much more thoroughly, but I find it quite interesting to read some of these comments:
quote:
The neutral theory of genetic evolution (24) predicts that the molecular clock is stochastic rather than metronomic, which means that the probability of change is constant, but that there will be variation around the expected rate of change. Already in the original molecular clock hypothesis, proposed by Zuckerkandl and Pauling (29), the observed rates of evolution were suggested to be approximately described by a simple Poisson process. Thus, this model predicts that the variance in the number of substitutions should be equal to the mean. However, many authors have reported the evolutionary rates of other organisms than HIV to be more dispersed than predicted by a Poisson process (overdispersion) (30-32), i.e., there is more variation in branch lengths in a tree than expected from a Poisson process. Several potential explanations for overdispersion have been proposed. It has been suggested that overdispersion may exist because mutant sites do not evolve independently (32). Another hypothesis invokes a generation-time effect, i.e., that the number of mutational errors will increase with increasing number of replication cycles. Interestingly, our simulation experiments indicated that neither the V3 clock nor the p17 clock were overdispersed (Fig. 4), which means that HIV-1 evolution can be described adequately by a neutral evolutionary model in which nucleotide substitutions are introduced by a stochastic process. Although positive and purifying (negative) selection events appear rare compared with neutral or nearly neutral substitutions they influence the evolution. Both positive and purifying selection instead may cause underdispersion, i.e., less variation than expected. If certain substitutions are not allowed then the variance will decrease. For instance, stop codons will not be tolerated in the middle of a gene, thus eliminating that genetic option. This process is observed as purifying selection and will be the same for every generation. In addition, positive selection will work as a dynamic force (not identical in every generation) that also restricts the genetic possibilities.
In this study, we have unveiled the molecular clock of HIV, which provides possibilities to explore important questions about the evolution of HIV, such as the origin and age of the virus. However, the true phylogenetic relationships between human and other primate lentiviruses must be investigated further. For instance, cross-species transmissions may have changed the substitution rates and genetic recombination may have obscured the evolutionary history. Finally, the molecular clock also can help determine the evolutionary possibilities and constraints for multidrug resistance and the possibilities for the virus to invade new ecological niches.
http://www.pnas.org/cgi/content/full/96/19/10752
IP: Logged
|
|
Fernando Castro-Chavez
Member
Member # 1201
|
posted 08. April 2004 00:41
Nobody,
Thank you for bringing to my attention that group. The article that you mention is hypothetical and of null practical use. More recently, the same group has done more practical and useful studies:
AIDS. 2003 Dec 5;17(18):2561-9. HIV biological variability unveiled: frequent isolations and chimeric receptors reveal unprecedented variation of coreceptor use. Karlsson et al.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=14685050
And also:
Casper et al, Coreceptor change appears after immune deficiency is established in children infected with different HIV-1 subtypes. AIDS Res Hum Retroviruses. 2002 Mar 20;18(5):343-52.
"It has not been possible to discern whether the appearance of new viral phenotypes precedes disease development or comes as a consequence of it." "Coreceptor use was tested on human cell lines, expressing CD4 together with CCR5, CXCR4, and other chemokine receptors. The children carried five different env subtypes (nine A, five B, four C, three D, and one G) and one circulating recombinant form, CRF01_AE (n = 2)." "A change from use of CCR5 to use of CXCR4 occurred in four children infected with subtype A, D, or CRF01_AE after they had reached 1.5 to 5.8 years of age." "Thus CXCR4-using virus may emerge as a possible consequence of immune deficiency."
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11897036
Especially in this last article we see that even with the extreme biological variability of HIV, and with all its things that still unknown; an ordered pattern seems to be starting to emerge. Once that we know the precise order of HIV change and the limits of its variability, then will be easier to track and block it in its earlier stages. This my last conclusion, based on non-evolutionist assumptions, but rather in facts, depicts once more the utility of Intelligent Design (and specifically in this case of IDc, or the "parasitism" raised against the original and perfect ID) in practical medical research (i.e., a search for a particular order and limits in variability).
[Additional Note: I used IDc (Intelligent Design corruption) to give an account of the existence of virus and of all the other 'Biological Advers-ities', 'Biological Abnormalities', etc.: thorns, thistles, venoms, predator behavior, etc. I can include here also the existence of Neanderthals, proven by many papers to have had a DNA and an mtDNA that were not human, but a product of IDc (Dr. Custance calls it 'a degenerative state'). Neanderthals were living contemporary, side by side with real humans. This is another example of an ID perspective 'leading to research questions otherwise left unasked', according to Dr. Bohlin, who also have said: 'evolutionists would not be likely to make such a prediction, since their search is primarily for apelike ancestors', they usually don't want to hear nothing about 'human-like monsters' in a degenerative state! (the same can be said of all the other 'humanoids-hominids', but evolutionsits may rather mock about it; and again, they may try to obstruct its research to keep 'alive' their own opinions, as they have done in the past to Cuvier, Mendel, Bateson, Custance, etc. But, are we going to shy away because of that?)]
[ 08. April 2004, 10:05: Message edited by: Fernando Castro-Chavez ]
IP: Logged
|
|
|
Printer-friendly view of this topic