Dr Page's best example of common descent explained from the GUToB.

And perhaps, Salty, you could be clear on why you disagree with crashfrogs statement? And what is wrong with the evidence for this statment?

The first sentence in your last paragraph is exactly what the semi-meiotic hypothesis predicts. A new species produced directly from a preexisting species in a single saltational event. At the same time the parent species retains the original genome in half of its progeny. Remember in the first meiotic division the sister (identical) strands always remain together. That is the essence of the semi-meiotic hypothesis. I know it sounds crazy but that is where I stand. Don't reject it without considering all the evidence. salty

So, it predicts something that we don't ever observe and that the competing, dominant theory says doesn't happen? Doesn't that cast major doubt on your theory? "It doesn't happen anymore", which I suspect is your defense, is no defense at all but rather evidence for the position "it never happened".Seems like you're shifting the goalposts here because you hold to an individual-centric biology. I once thought as you did, and speciation mystified me. When I "awakened" to the significance of populations and gene pools to speciation, it was almost an epiphany. When you consider species as population-level classifications it really makes much more sense, and no outlandish theories need be invoked.------------------
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Semi-meiosis does still happen. It is exactly the way certain flagellate protozoa in the genus Spirotrichosoma reproduce. I present that in the 1998 paper Evolution as a self-limiting process. It is also the cytological device by which male parthenogenetically produced turkeys are formed. There may be many other examples which have not been discovered as one cannot assume sexual reproduction just because both sexes are present. salty

But that's still no reason to reject modern synthesis ToE. At best you've uncovered some unique species that utilize dual-gender specification in totally different ways. So your semi-meiotic hypothesis could simply be integrated to the larger modern theory (except for the bit about sexual reproduction ending speciation, which has been shown to be false). You haven't really shown any reason why your hypothesis is correct to the exclusion of the modern synthesis, which says things like "populations speciate when reproductively isolated from their parent population", etc.It sounds like you're generalizing from a few widely separated sexually anomalous species, and trying to apply that generalization to the entire living world, in the face of contradictory data that shows that sexual populations continue to speciate to this day.I agree, though - just because a species has two genders doesn't mean sexual reproduction is the only way they breed. But I think it can be inferred that sexual reproduction will be the dominant reproductive technique because it's really good at maximizing the adaptive force of natural selection, as genetic programming studies on computers have demonstrated.------------------
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Crashfrog. I remain convinced that no sexually reproducing organism can ever become anything very different from what it is now. Can you imagine a dog evolving into a cat? So let's assume (purely for argument) that a sexually reproducing organism can transcend the species, does that mean that a new Genus is also within evolutionary reach, or a new family etc. etc. I give a resounding no to those questions. I am an experimental biologist. There is not a single experiment demonstrating macroevolution (speciation)through mutation/selection. Dobzhansky tried and failed. It never even crossed the mind of Luther Burbank. Is that to be ignored? I don't think so. salty

Crashfrog. Of course sexual reproduction is the dominant reproductive technique. It is great for fine tuning but incompetent as a progressive evolutionary device. Besides, that is to be expected because apparently macroevolution is finished. The modern synthesis has led us nowhere. It is time to abandon it. salty

Salty asks: Can you imagine a dog evolving into a cat?I can imagine it, but I don't really have to. Dogs didn't evolve into cats. They both evolved from Miacis, and it took some 40 million years. Of course, as a former biology professor, I am sure you knew this. But if you did know this, then your dog into cat example is a strawman.40 million years is a long time, Salty. It is even older than you are. I don't believe anyone has been actively trying to speciate mammals for this length of time, which is a reason why examples of higher level speciation in the lab are not that common. The evolutionary explanation is that it takes many, many generations for enough genetic difference to accumulate to confidently declare speciation. Your explanation is that it occurs in a generation, but it conveniently is no longer occurring. I think I will stick with reality.Incidentally, do you really believe, that given 40 million years that the current chihuahua and St. Bernard breeds could not easily end up being very different species? Genetic differences are accumulating each generation. Given enough time, speciation is practically inevitable.FK[This message has been edited by Fedmahn Kassad, 04-20-2003]

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sexual reproduction will be the dominant reproductive technique because it's really good at maximizing the adaptive force of natural selection, as genetic programming studies on computers have demonstrated

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There is also plenty of real world experimental data to support this idea:COLEGRAVE N. Sex releases the speed limit on evolution. Nature 420, 664 - 666 (2002)"Here I show that sex can increase the rate of adaptation in the facultatively sexual single-celled chlorophyte Chlamydomonas reinhardtii"Colegrave N, Kaltz O, Bell G. Related Articles, Links
The ecology and genetics of fitness in Chlamydomonas. VIII. The dynamics of adaptation to novel environments after a single episode of sex.Evolution Int J Org Evolution. 2002 Jan;56(1):14-21Rice, W. R., & A. K. Chippindale. Sexual recombination and the power of natural selection. Science 294: 555-559."Our results experimentally verify a counteracting advantage of recombining compared to clonal lineages: reduced accumulation of harmful mutations and increased accumulation of beneficial mutations."

Actually I know about the book that you were refering to but it was not available my last time at the library, I very much understand why it is not on the web. Most whole books are not due to copyright restrictons and the general irritation of scanning a whole book which is not already in electronic format, as many older books are not. I have read some Schindewolf and some Grass and can not agree with you that they demolish the Neo-Darwinian theories. I also have read some of Goldschmidt's work and see where his major problems were with rates of mutational jumps, and not so much with Natural Selection persay. Your chromosomal re-arrangements within your manifesto are also mutations, just on a different scale, kind of like deletions within control regions. They actually work by changing gene expression and by changing specific genes, depedning on the re-arrangement. One reason that chromosomal rearrangement is not discussed much in NeoDarwinian theory is that the molecular aspects are too complicated for current methodologies, but that is slowely changing.------------------
"Chance favors the prepared mind." L. Pasteur
Taz[This message has been edited by Dr_Tazimus_maximus, 04-20-2003]

Evolutionary (species and higher categories) changes did not take millions of years at all. Most were probably complete in minutes. Just because the earth is very old means nothing with respect to evolution rates. The semi-meiotic hypothesis predicts instant evolution. That was the substance of my paper which moose introduced here. I stick to my guns. Macroevolution is over. Oddly it was the author of the Modern Synthesis, Julian Huxley who said as much. He stole the idea from Robert Broom and never bothered to credit Broom for it. Grasse said as much as well. These were reasoned conclusions based on the fossil record. I have far more confidence in Broom, Berg, Bateson and Grasse than I have in all the proponents of gradualism combined. They are chasing a phantom. Sorry, but that is my position. salty

I am quite aware of your assertions, but how about some evidence that dog evolution, for example, was instantaneous? Since your views are so far from the mainstream, I would think you would be more than willing to provide evidence and address criticisms if you want to be taken seriously.Here is the mainstream view of dog evolution. Miacis, which lived 40 million years ago, evolved into Cynodictis, which lived about 20 million years ago, to Tomarctus, about 10 million years ago, to Canis, about 1 million years ago. All living canine species are derived from the common ancestor Tomarctus. There is a similar family tree, starting from Miacis and ending up with house cats. All of this is supported by the fossil record, with the proper intermediates occupying to correct position in the geological column.Please present your alternate scenario for dog evolution. Please be specific in order to be taken seriously. What did dogs evolve from? How many intermediate steps did it take? Making assertions and then saying "Sorry, but that is my position" will be taken as evidence that you can't support your position.FK

Why are they all in different genera? It looks to me lke most trees with jumps between forms but with no evidence for gradual transformation. The main problem with the gradualist position is that it isn't testable. At the present state of our knowledge it really depends largely on what our preferences are. I am a convinced saltationist and as one might gather from my papers and those of my references a convinced antiDarwinist. The gradual transformation of one species into the next has never been demonstrated. It is my view that it never will be. salty

Sure it's testable. One test would be the hypothesis "if the gradualist position is accurate, we should see intermediate forms between any two related species, each form occupying a position in the fossil record that we can roughly predict, by inferring from observed mutational rates in the lab." That is to say, because we see the first steps of speciation in the lab, with small differences between species over short time frames, we infer that with more time, greater and greater changes can accrue. If you disagree with this inference you'll have to have a good reason.Anyway, the fossil record bears out that changes in populations haven't really happened any faster in the past than they do today, at least within the limited capacity of the fossil record to give data about short time periods.Since we know species change a little in the short term (enough, though, to become new species), can you give a reason why it would be wrong to assume those changes can't add up to great change over the long term? It's a pretty reasonable assumption to me.

Salty: Why are they all in different genera?Because they are separated by millions of generations, during which accumulating mutations increased the genetic differences.Salty: I am a convinced saltationist and as one might gather from my papers and those of my references a convinced antiDarwinist.I understand. But you aren’t convincing anyone else by refusing to defend your ideas.Salty: The gradual transformation of one species into the next has never been demonstrated. It is my view that it never will be.I guess that depends on what you are expecting to find. If you want changes as dramatic as the difference between cats and dogs, then you are probably correct. That won’t be directly observed because it takes millions of generations.Now, once more I ask for your version of dog evolution. How does it work in a saltationist world?That's all for today. I have to go hide Easter eggs.FK