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Topic: Prof. Davison's Challenge to NDE
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Jehu
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Member # 1981
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posted 26. May 2006 12:52
Prof. John Davison has made three challenges to Darwinism. Those challenges are as follows.
1. Name any two species fossil or extant and present any evidence from any source that one is ancestral to the other.
2. Name a mammalian species younger than Homo sapiens.
3. Present evidence that any new species has evolved in historical times.
We are all waiting to see if anyone will rise to the occasion.
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Bruce Fast
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posted 26. May 2006 13:17
Let me just add, that in all of Dr. Davison's work, the traditional biological definition of a species is used, "two fertile members of the same species can normally mate producing fertile offspring." Unless the "mating" test has been administered, any evidence provided about speciation must be disregarded.
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Jehu
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posted 26. May 2006 15:51
I posted the challenge on ARN to try to get more takers and N. Wells posted the following reply: quote:
From the Botanical Society of America, at http://www.botany.org/newsite/announcements/evolution.php : Wheat is an ancient crop of the Middle East. Three species exist both as wild and domesticated wheats, einkorn, emmer, and breadwheat. Archeological studies have demonstrated that einkorn is the most ancient and breadwheat appeared most recently. To plant biologists this suggested that somehow einkorn gave rise to emmer, and emmer gave rise to breadwheat (an hypothesis). Further evidence was obtained from chromosome numbers that showed einkorn with 14, emmer with 28, and breadwheat with 42. Further, the chromosomes in einkorn consisted of two sets of 7 chromosomes, designated AA. Emmer had 14 chromosomes similar in shape and size, but 14 more, so they were designated AABB. Breadwheat had chromosomes similar to emmer, but 14 more, so they were designated AABBCC. To plant biologists familiar with mechanisms of speciation, these data, the chromosome numbers and sets, suggested that the emmer and breadwheat species arose via hybridization and polyploidy (an hypothesis). The Middle Eastern flora was studied to find native grasses with a chromosome number of 14, and several goatgrasses were discovered that could be the predicted parents, the sources of the BB and CC chromosomes. To test these hypotheses, plant biologists crossed einkorn and emmer wheats with goatgrasses, which produced sterile hybrids. These were treated to produce a spontaneous doubling of the chromosome number, and as predicted, the correct crosses artificially produced both the emmer and breadwheat species. No one saw the evolution of these wheat species, but logical predictions about what happened were tested by recreating likely circumstances. Grasses are wind-pollinated, so cross-pollination between wild and cultivated grasses happens all the time. Frosts and other natural events are known to cause a doubling of chromosomes. And the hypothesized sequence of speciation matches their observed appearance in the archeological record. Farmers would notice and keep new wheats, and the chromosome doubling and hybrid vigor made both emmer and breadwheat larger, more vigorous wheats. Lastly, a genetic change in breadwheat from the wild goatgrass chromosomes allowed for the chaff to be removed from the grain without heating, so glutin was not denatured, and a sourdough (yeast infected) culture of the sticky breadwheat flour would inflate (rise) from the trapped carbon dioxide.
There has been endless back and forth discussion about some specific details, but overall there seems to be no dispute that these are historically novel species that fall outside the normal concept of interbreeding.
Note also that interbreeding is a useful demarcation, but it is not an obligatory one: the MET predicts that there can be episodes of actual interbreeding or a period of potential interbreeding during a speciation. If speciation proceeds to completion, under many speciation processes, interbreeding should become increasingly less frequent, less easy, and less favored. Thus the boundary between species is expected to be "fuzzy".
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John A. Davison
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posted 26. May 2006 16:10
Wrong Bruce. there are thousands of species for which no test is even necessary because even artificial fertilzation is quite impossible so the hybrid cannot even be generated.
One of the things that continues to interest me is whether or not chimp / human crosses have been attempted and if not why not. I see no compelling reason why the hybrid might not survive, but the hybrid most certainly would be 100 percent sterile. Think of the receipts at the circus!
There is an interesting historical twist to this suggestion. Josef Goebbels, Hitler's Propaganda Minister, once proclaimed, and I paraphrase:
"It has not yet been demonstrated that non-aryans cannot hybridize with apes."
Apparently the Germans had performed such experiments with negative results.
Here are some intersting facts. The Darwinians steadfastly refused to test Darwin's finches for hybrid fertility and still have not done so even though finches are among the easiest of all birds to domesticate. It turns out that it is probably not necessary anyway becasue the Grants have observed normal fertility and fitness among spontaneous natural hybrids. All of Darwin's finches are apparently a single species, just as all dogs are wolves and all the bizarre phenotypes of the Asiatic carp (Carassius auratus) are a single species as well.
The truth of the matter is that the Darwinians no longer even dream of testing either natural or artificial selection because they live in mortal fear of what such experiments might divulge. It is sad but very true and devastatingly revealing for the failure of the selectionist paradigm. Natural selection never had anything whatsoever to do with creative evolution just as Leo Berg and Reginald Punnett insisted long ago.
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John A. Davison
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posted 26. May 2006 16:25
Chromosome doubling undoubtedly can occur, especially in certain plants, and it leads nowhere. It is just another evolutionary dead end. I see no evidence for creative progressive evolution in progress today and neither did Pierre Grasse.
"Aren't our plants, our animals lacking some mechanisms which were present in the early flora and fauna."
Evolution of Living Organisms, page 71.
I answer with an emphatic, unqualified yes! Furthermore I have postulated that missing mechanism with the Semi-Meiotic Hypothesis (SMH).
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Bruce Fast
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posted 26. May 2006 17:08
quote:
Wrong Bruce. there are thousands of species for which no test is even necessary because even artificial fertilzation is quite impossible so the hybrid cannot even be generated.
Huh? My "definition of a species" would certainly place two animals into separate species if they were not able to mate. If they normally can mate, and if their offspring are normally fertile, then they are the same species, otherwise not. This is the classic biological definition, is it not?
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Jehu
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posted 26. May 2006 17:11
As far as human chimpanzee breeding goes, the Darwinists have already tried it. In 1926, a Soviet scientist named Ilya Ivanov attempted the experiment and it failed.
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Jehu
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posted 26. May 2006 17:17
Here is another reference for new species.
Dobzhansky T & O Pavlovsky (1966). Spontaneous origin of an incipient species in the Drosophila paulistorum complex. PNAS 55: 727-733. quote:
A strain established in the laboratory from flies collected in the Llanos of Colombia in 1958 behaved at first as a member of the Orinocan incipient species.By 1963 it changed so that its male F1 hybrids with other Orinocan strains became completely sterile. The backcross hybrids, however, continue fertile, and no strong ethological isolation from Orinocan strains has arisen.
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John A. Davison
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posted 26. May 2006 20:38
Jehu
I neglected to thank you for introducing this thread. Sorry.
There are always examples that might be interpreted as examples of novel speciation, but have any of them been verified and even if they survive the acid test proposed by Dobzhansky, is anyone, anywhere weak-minded enough to really believe that these represent examples of a progressive productive future evolution? I certainly am not and I cannot imagine how anyone else can be either. Evolution is for all practical purposes no longer in progress and I still await specific examples of a progressive ascending process in operation anywhere on earth. All that I see is the exact opposite, with innumerable life forms disappearing at an alarming rate, never to be replaced. Just as ontogeny terminates with death so has evolution terminated with extinction. We see it every where we look or at least I do. If others see otherwise I say good for them.
Thanks again for posting this thread.
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John A. Davison
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posted 27. May 2006 05:01
Please do not think that these ideas have originated with me. It was the arch Darwinian, Julian Huxley, author of "Evolution: THe Modern Synthesis," who claimed in no uncertain terms that evolution is finished, an idea he got from the writings of the antiDarwinian Robert Broom with whom he had carried on a correspondence in the early nineteen-thirtys. I documented the entire exchange in the Manifesto. Sadly, Huxley's only reference to Broom was in a foot note in which he essentially described Broom as a mystic.
I heard Robert Broom, then in his eighties, lecture in a course I was taking in Physical Anthropology at the University of Wisconsin in 1948 or 1949. I will never forget that lecture as it was obvious that one was in the presence of a great scientist. Little did I know then that he would become such a powerful influence when I became interested, 35 years later, in the great mystery of organic evolution.
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Melvin H. Fox
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posted 28. May 2006 22:07
Here I have prepared some thoughts directed to Zachriel with regard to his comments made on another thread [REPRODUCTIVE ISOLATION]. It was pointed out that the subject of these comments were not germane to that line of thought. I hope they will find a home here.
Zach,
Permit me to take these one at a time. “It can be observed that not all organisms will normally exchange genes.” I certainly don’t have any problem with this statement. “Reproductive isolation can be observed to be a gradient and subject to various exceptions.” I take this as you mean populations are isolated to varying degrees from minor hindrances to total blockage. What exceptions do you refer to? “Even organisms long regarded as distinct species have been known to interbreed.” How is it that this fact does not disintegrate the entire hypothesis? “Fertility in offspring is also a continuum.” How is this important? “Gene flow between populations is the determinant.” Do you mean to say that there exists some tolerable non zero gene exchange between populations of different species? If so, don’t you see the problem some intelligent people might have with calling these two populations different species when gene flow, however small, does in fact exist between them?
-Mel
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Zachriel
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posted 29. May 2006 08:41
Melvin H. Fox: "Permit me to take these one at a time."
That would be appropriate as I meant the statements to be taken more or less consecutively.
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Zachriel: It can be observed that not all organisms will normally exchange genes."
Melvin H. Fox: ""I certainly don't have any problem with this statement."
As it is an observation, we would hope not.
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Zachriel: "Reproductive isolation can be observed to be a gradient and subject to various exceptions."
Melvin H. Fox: ""I take this as you mean populations are isolated to varying degrees from minor hindrances to total blockage. What exceptions do you refer to?"
This is also an observation. So for instance, populations within a single species may diverge as they adapt to local environments. As long as there is significant gene flow, they may remain a single species, and the varieties are usually called breeds. On the other hand, there are many populations that never or almost never interbreed. They might interbreed, but have been separated (e.g. by geography) for so long that there has been no significant gene flow and have developed differentiated characteristics. They might breed if caged up, or by artificial insemination, but wouldn't be likely to do so if encountering one another in the wild. Or their young might be less fertile or simply unattractive to potential mates, so the hybrid might die out in a few generations, or be reabsorbed into the parent population losing the alien genes.
Most of the great cats can be hybridized, but rarely will do so in the wild. Equine species are another example. On the other hand, sunflowers and grasses can readily hybridize and often do.
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Zachriel: "Even organisms long regarded as distinct species have been known to interbreed."
Melvin H. Fox: "How is it that this fact does not disintegrate the entire hypothesis?"
It confirms it. If speciation is a process of slow divergence in isolated populations, a continuum of reproductive isolation is exactly the pattern expected.
The fact is that there are varying degrees of reproductive isolation. Lions and tigers are rightly considered separate species. Even though they can interbreed; there is no significant gene flow. Don't let a particular definition of 'species' confuse you to the underlying reality.
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Zachriel: "Fertility in offspring is also a continuum."
Melvin H. Fox: "How is this important?"
Even if two organisms can interbreed, their offspring may not be fertile, or may have reduced fertility. This will effect the rate of gene flow between populations. The lower the gene flow, the greater the effects of divergence either due to varying environmental conditions, or stochastic processes.
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Zachriel: "Gene flow between populations is the determinant."
Melvin H. Fox: "Do you mean to say that there exists some tolerable non zero gene exchange between populations of different
species?"
Of course. This isn't news. Again, don't confuse a particular definition of the word 'species', or perhaps a misunderstanding of the concept, with the actual biological facts. Each of the categories of reproductive isolation, fertility and gene flow can constitute gradients, but are nonetheless real facts concerning biology.
Melvin H. Fox: "If so, don't you see the problem some intelligent people might have with calling these two populations different species when gene flow, however small, does in fact exist between them?"
It has always been known that different species can interbreed under certain circumstances. It's called hybridization. And this is the precise pattern we would expect if speciation is a product of slow evolutionary divergence in isolated populations.
My guess is that these intelligent people confuse the abstract categorization with the reality. I suppose in a perfect world, everything would fit into nice neat boxes. But that is not the world we find ourselves in.
It is observed that populations experience varying degrees of gene flow. At the point when gene flow slows sufficiently that populations develop unique and distinguishing characteristics, that has usually led biologists to classify them as separate species. That biologists often disagree about the application of the 'species' label concerning closely related organisms just indicates how nebulous (chaotic) the exact barrier may be. Some biologists count dogs and wolves as a single species, for instance; others don't. Once completely isolated, such lineages form the familiar nested hierarchy of descent.
In any case, it isn't the words or classifications that matter, but the biological facts.
--
Zachriel
Angel that rules over memory, presides over the planet Jupiter.
http://zachriel.blogspot.com/
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Zachriel
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posted 29. May 2006 09:26
Darwin, Origin of Species (1859): "It is certain, on the one hand, that the sterility of various species when crossed is so different in degree and graduates away so insensibly, and, on the other hand, that the fertility of pure species is so easily affected by various circumstances, that for all practical purposes it is most difficult to say where perfect fertility ends and sterility begins."
Keep in mind that Darwin did not have knowledge of a valid theory of genetics and was working in the context of 19th century British naturalism. Nevertheless, the Theory of Evolution has always incorporated *as fundamental* the observation of a gradation of reproductive isolation.
Darwin: "Finally, then, the facts briefly given in this chapter do not seem to me opposed to, but even rather to support the view, that there is no fundamental distinction between species and varieties."
[ 29. May 2006, 09:32: Message edited by: Zachriel ]
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Bruce Fast
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posted 29. May 2006 13:17
Zachriel, to summarize what you have said, there is no crisp definition that deliniates species. Even the definition I proposed earlier has the imprecise term "normally" stuffed into it because of this.
I find this to be remeniscent of Dr. Denton's description of evidence for speciation. I also find the lack of a clear and reliable demarkation between species to be a compelling case for naturally occurring (NDE) speciation.
Zachriel: (Brainstorms, "Can some aspect of Darwinism be Falsified" 21 May, 2006)
quote:
In an evolving system, there is also a scale-invariant process of change. Most change is tangential and minor, some change is substantial, and very occasionally change is revolutionary. This is analogous to self-organizing criticality in landslide patterns.
I take this to mean that speciation is this gradual process where it is difficult to determine when an animal has actually crossed the line and become a new species. I remain puzzled at what I see as Dr. Denton's strongest case for PEH, that the evolutionary tree was deveoped from the trunk first (domain, to kingdom, to phylum ... )
Your description above, a description that seems to make sense in light of NDE, would suggest that at some random point, a new family should pop up, or a new order, or phylum. Yet it seems that nature has gone into "I'm gonna build the phylums" mode, or "I'm gonna build the classes" mode.
Why do we not see new phylums, orders, classes etc. pop up with the kind of pattern one would expect of a random event, 1 here, a few million years later another, maybe a 20 million year gap then possibly two in a row? This is the general pattern that one might expect when applying NDE to an hypothetical world.
As you mentioned, one may expect to see some amount of burst activity due to some contingency (the crashing of a meteor, for instance) but this pattern is shockingly strong and consistent. So far I have found nothing in NDE that realisticly accounts for it.
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