Define 'species'

[mark kennedy]

No, I am talking about any kind of selective pressure. I am not talking about allopatric speciation. Let's stick to Mendel's basics. Because you have me totally confused as to whether you understand them.

And sure I know there are many complexities. The point is, we can't begin to tackle the complexities until the basics are down pat. So throwing them up now is just dancing around the question without answering it.

So, in spite of the many complexities, I want to talk basics first.

Several times you have mentioned not just the H-W equilbrium, but the 3:1 ratio specifically. I want to know if you understand and agree that a 3:1 ratio in phenotype implies a 1:1 ratio in alleles.

Second, do you agree Mendels' work was based primarily on crossing two varieties which bred pure for the trait(s) he was testing, e.g. smooth or wrinked skin, yellow or green seed colour, etc. What does that imply for the genotype of the parents of the F1 generation.

If you have a tall plant crossed with a short one and they yeild only tall plants the tall plant genes are said to be dominant while the short ones are called recessive. When analyzing genetic crosses, the first generation is the parental generation, or P1, the second generation is the first filial generation, or F1; the net generation is the second filial generation, or F2 and so on.

Your grandparants are the P1 generation and your parents would be the F1 generation and you and your siblings are the F2 generation.

You know the words "dominant" and "recessive". I am not sure you know what they mean. How do they explain the phenotypes of the F1 and F2 generations?

The phenotype describes the outward expression of an allele combination. Now a little semantical question for you. Distinguish between wild type phenotype and a mutant.

Mendel had no interest I know of in subjecting his plants to selection pressures. Rather he needed to give all his test subjects an equal opportunity to reproduce.

What if he had decided to impose a selective pressure. How would he exert a selective pressure in favour of a dominant trait? What would be the expected result in the next two-three generations? How would this differ if he exerted a selective pressure in favour of a recessive trait?

Homozygous or heterozygous?

Creationist mantra: Evolution is not evolution. The above sentence ought to read "This is really nothing more than evolution." because that's what adaptation is. Or to be a little more precise, adaptation is the outcome of evolution. In short, no evolution = no adaptation.

Evolutionist mantra: Any change or adaptation proves the universal common ancestor model conclusivly

Genotypes and phenotypes. After all what is being selected is a phenotype. It is the selection of the favored phenotype that results in a favoured genotype. btw, this is also evolution.

Well yes if evolution is definined as the change in gene frequencies in populations over time. It when you ad the metaphysics of naturalistic assumptions that the meaning gets convoluted.

Indeed it is. Too bad more creationists don't appreciate it as such.

I just asked if the Mendel laws of inheritance could measure a transitional mutation. The answer would be of course it does. Now as far as a transitional, like say the hominid, I was just asking what you would expect the level of change that would be nessacary. Transitionals are allways rare and appear rather suddenly in the geologic strata.

I know that genes change, its just not very substantial proof for universal, unicellular common ancestory.

 

[Vance]

Mark, could you explain what you mean by "metaphysics of naturalistic assumptions"?

Also, you seem to be quoting the same line that "Transitionals are allways rare and appear rather suddenly in the geologic strata". This is a strange mixture of the typical misunderstanding of the concept of transitionals and a failure to grasp evolutionary time frames.

There are NO fossils that we label as "transitionals" in their own right. And at the same time, EVERY fossil is a "transitional". Any fossil is only transitional in that it comes in between two other species in the development process, in which case, we would call that transitional between the two. But, both species we may point to on either side would also be transitional between earlier and later species. So, "transitional" is simply a relational term, not a firm label. So, no, transitionals are not rare. There are as many transitionals as there are fossil species.

Second, "suddenly" in evolutionary terms means thousands or even tens of thousands of years, as Gould points out. When a species has a long run without change, it will produce very similar fossils over a long time period. When the pressures change and cause evolutionary development, the creature will change at the pace and in the direction the pressure requires. If that change rises to the level of a new species, then you will have a new species. Now, let's say that a species (A) leaves a single fossil every 100,000 years on average. We may have ten fossils in a row showing no change whatsoever, covering 1,000,000 years. Then, some event occurs, such as a major weather shift, the introduction of a new predator or food source, etc. The evolutionary pressure mount and the changes begin. Over the course of, say, 80,000 years of this evolutionary development (ie "sudden"), a new species evolves from the A's living in the effected area (we'll call the new species B), and this species has significant morphological changes. We happen to have a fossil for that new species, and we find further fossils that are very similar to B over the next half million years now that the species has adapted to its new environment. The fossil record will look like A - A - A - A - A - A - A -A - A - A - B - B - B, etc. Now, B looks like it appears suddenly in the fossil record. But there was still a complete evolutionary development from A to B, it just happened too "quickly" for the fossil record to be able to record those developments.

Other times, the evolutionary process happens slow enough, or the fossil record is complete enough, that we actually get to see the changes taking place in incremental fashion. But because of the extreme rarity of fossils and the (relative) speed at which some change occurs, the "sudden" appearance seems very common.

Where YEC's go wrong is when they take soundbite quotes from real scientists talking about "suddeness" and "wow, we didn't expect that!" and using terms like "difficulties" and "problem" and misleadingly use them to convey the impression that these scientists are actually coming to disbelieve in evolutionary theory. Ask ANY of these scientists if their comment meant that they have any doubts about the validity of evolutionary theory and they would just look at you strange and say "well, of course not, we are just discovering how it works, and we are constantly finding out more and refining our theories to fit the evidence, but the basic concept is still the same and still works to explain the diversity of species just fine".

 

[gluadys]

I am very disappointed in your response Mark. I feel you are being evasive.

For example, you negelected this question entirely:

Several times you have mentioned not just the H-W equilbrium, but the 3:1 ratio specifically. I want to know if you understand and agree that a 3:1 ratio in phenotype implies a 1:1 ratio in alleles.

And this:

Second, do you agree Mendels' work was based primarily on crossing two varieties which bred pure for the trait(s) he was testing, e.g. smooth or wrinked skin, yellow or green seed colour, etc. What does that imply for the genotype of the parents of the F1 generation.

You said:
" If you have a tall plant crossed with a short one and they yeild only tall plants the tall plant genes are said to be dominant while the short ones are called recessive. When analyzing genetic crosses, the first generation is the parental generation, or P1, the second generation is the first filial generation, or F1; the net generation is the second filial generation, or F2 and so on. "

Correct. Now how does this relate to the H-W equilibrium? And the genotypes of P1, F1, F2 and future generations?


You said:

"The phenotype describes the outward expression of an allele combination."

And what does that imply for the genotype of an organism showing a dominant trait as compared to the genotype of an organism showing a recessive trait?


You asked:

" Distinguish between wild type phenotype and a mutant."

To me the question doesn't make much sense. What is a "wild type phenotype"? How does it differ from a "non-wild type"?

By "mutant" do you mean a genetic change or a phenotypic change?

Mendel had no interest I know of in subjecting his plants to selection pressures. Rather he needed to give all his test subjects an equal opportunity to reproduce.

What if he had decided to impose a selective pressure. How would he exert a selective pressure in favour of a dominant trait? What would be the expected result in the next two-three generations? How would this differ if he exerted a selective pressure in favour of a recessive trait?

Homozygous or heterozygous?

Both.

Evolutionist mantra: Any change or adaptation proves the universal common ancestor model conclusivly.

No, it doesn't. All it shows is that evolution happens. And that is sufficient to show the common ancestry of the species involved. That is why creationists can agree that a certain amount of evolution happens---though they like to hide that admission under terms like variation or adaptation.

But universal common ancestry is implied--unless one can point to species or groups of species that cannot be so related. Or discover a mechanism whereby a parental species cannot become a grandparental species.

Well yes if evolution is definined as the change in gene frequencies in populations over time. It when you ad the metaphysics of naturalistic assumptions that the meaning gets convoluted.

I don't know what you mean by "naturalistic assumptions". Could you give me an example?

I just asked if the Mendel laws of inheritance could measure a transitional mutation.

Well, Mendel's work applies more to allele distribution than to mutations. I expect what it could measure is the rate of spread of a new allele in the population.

The answer would be of course it does. Now as far as a transitional, like say the hominid, I was just asking what you would expect the level of change that would be nessacary.

You need to watch your definitions. "Hominid" does not refer to a particular species or group of species labelled "transitional". It refers to all species living and extinct which share a set of characteristics. You and I are hominids. Maybe, someday in the far distant future, you and I will also be labelled "transitional".

Currently, hominids include a group that is wholly extinct, know as "australopithecines". They are commonly thought of as transitional between an ape-like primate and the genus Homo. But that doesn't make them the only hominids. All species of Homo including H. sapiens are also hominids.

As Vance rightly points out, technically, all species are transitional. It's just that in the case of living species, we don't necessarily know what they are transitional to.

I know that genes change, its just not very substantial proof for universal, unicellular common ancestory.

Well, it makes sense to me. Especially as all biological evidence points in that direction.
I know we don't have a way to generate a species by species lineage for every living organism. We never will. But we have enough that I would need some pretty solid disconfirming evidence to reject the thesis of a universal common ancestor.

 

[mark kennedy]

Mark, could you explain what you mean by "metaphysics of naturalistic assumptions"?

Metaphysics has been called a theory about everything. Formal metaphysics is a substative element that transends all reality. Clearly the evolutionary thinker sees evolution and an all inclusive term:

"In the broadest sense, evolution is merely change, and so is all-pervasive; galaxies, languages, and political systems all evolve. Biological evolution ... is change in the properties of populations of organisms that transcend the lifetime of a single individual. The ontogeny of an individual is not considered evolution; individual organisms do not evolve. The changes in populations that are considered evolutionary are those that are inheritable via the genetic material from one generation to the next. Biological evolution may be slight or substantial; it embraces everything from slight changes in the proportion of different alleles within a population (such as those determining blood types) to the successive alterations that led from the earliest protoorganism to snails, bees, giraffes, and dandelions."
- Douglas J. Futuyma in Evolutionary Biology, Sinauer Associates 1986


Everything, galaxies, languages, political systems, bloodtypes and earliest common ancestor, the protoorganism. You guys seem to be under the impression that I am overtly hostile to biological evolution. Consider this, the creationist must believe in a far more vigorous speciation and transmutation of the multiple varieties of life on this planet.

Also, you seem to be quoting the same line that "Transitionals are allways rare and appear rather suddenly in the geologic strata". This is a strange mixture of the typical misunderstanding of the concept of transitionals and a failure to grasp evolutionary time frames.

Fossils from 4-19 million years ago for hominoid and hominid (ancestral to humals only) are scarce, plain and simple. This crucial point of transition from some kind animal to Homo Habilis (where tools appear on the same geologic horizon) and this is said to be some 2 million years old. I don't know why this isn't fascinating for the Darwinian.

There are NO fossils that we label as "transitionals" in their own right. And at the same time, EVERY fossil is a "transitional". Any fossil is only transitional in that it comes in between two other species in the development process, in which case, we would call that transitional between the two. But, both species we may point to on either side would also be transitional between earlier and later species. So, "transitional" is simply a relational term, not a firm label. So, no, transitionals are not rare. There are as many transitionals as there are fossil species.

The period from 19 to to 2 million years ago is obviously going to include a lot more then one or two transitionals.

Second, "suddenly" in evolutionary terms means thousands or even tens of thousands of years, as Gould points out. When a species has a long run without change, it will produce very similar fossils over a long time period. When the pressures change and cause evolutionary development, the creature will change at the pace and in the direction the pressure requires. If that change rises to the level of a new species, then you will have a new species. Now, let's say that a species (A) leaves a single fossil every 100,000 years on average. We may have ten fossils in a row showing no change whatsoever, covering 1,000,000 years. Then, some event occurs, such as a major weather shift, the introduction of a new predator or food source, etc. The evolutionary pressure mount and the changes begin. Over the course of, say, 80,000 years of this evolutionary development (ie "sudden"), a new species evolves from the A's living in the effected area (we'll call the new species B), and this species has significant morphological changes. We happen to have a fossil for that new species, and we find further fossils that are very similar to B over the next half million years now that the species has adapted to its new environment. The fossil record will look like A - A - A - A - A - A - A -A - A - A - B - B - B, etc. Now, B looks like it appears suddenly in the fossil record. But there was still a complete evolutionary development from A to B, it just happened too "quickly" for the fossil record to be able to record those developments.

80,000 years of development would be very sudden in the evolutionary cycles particularly since there is very little change in the interium. Look at it this way, actually a Darwinian is a pretty conservative evolutionist, the creationist would be more of a radical evolutionist. Think about how many fossils we have for say the hominids, maybe 1,000 identified and some 3,000 extant. In just under 10,000 years all these fragments have been fossilized and that doesn't even account for the many others. I don't know why you guys aren't beating me up over saying they are rare.

Your describing gradualism but you don't seem to understand, I'm a radical evolutionist. If you really think about YEC in the light of the legitamate natural science the creationist is actually going to have to admit that fossils are not rare at all, bones would have to be fossilized almost constantly.

I know at this point you are probably thinking I should be sent somewhere to learn fingerpainting and basket weaving. I don't hate evolution, heck, I need it in the worst possible way and I appreciate all the help I'm getting with it.

 

[Vance]

"Fossils from 4-19 million years ago for hominoid and hominid (ancestral to humals only) are scarce, plain and simple. This crucial point of transition from some kind animal to Homo Habilis (where tools appear on the same geologic horizon) and this is said to be some 2 million years old. I don't know why this isn't fascinating for the Darwinian."

Don't you think that if it was particularly significant, it actually *would* be fascinating? Do you think evolutionary biologists are just missing something crucially important that you happen to know about? I am sure they would love to hear about it. In fact, even *we* would love to hear about it.

"The period from 19 to to 2 million years ago is obviously going to include a lot more then one or two transitionals."

Well, I count nine different hominid species (and many fossils for each) found so far, and that is just from 2my going back to about 7my. And more are being discovered every few years. And remember, these are not "transitionals", as if they are merely place-holder species in the process of change, on the way to their "true" goal. Each was a fully functional species adapted to its particular environment. Each is a legitimate being in its own right, I am not sure they would appreciate being considered a mere "transition" between one thing and another.

You might want to check out this site for a good summary of the state of current finds. It also has a full discussion of the issues as well as the actual Creationist arguments you might find useful.

http://www.talkorigins.org/faqs/homs/

"80,000 years of development would be very sudden in the evolutionary cycles particularly since there is very little change in the interium. . . ."

But you completely ignored my point. You are saying that new "transitional" species are "rare" and that they appear "suddenly" and fully formed. I may be wrong, but you seem to be implying that this must mean that there was something other than accepted evolutionary processes going on. Most Creationists would want to insert a special creation or other special "zing" not explained by evolutionary theory (ie, God of the Gaps). My point is that the "appearance" of a sudden change is entirely explainable in evolutionary terms.

On the other end of the spectrum (in case you are following the AIG models) it is absolutely impossible for the evolutionary process to take place fast enough for the variety of species we see today to have developed within the last 10,000 years (much less since the time of a supposed flood, from group of "kinds"). In fact, it could not have taken place within the last 1,000,000 years.

So, the progressive Creation model is an entirely unecessary God of the Gaps formulation (as much as I appreciate Hugh Ross for making such strong arguments against YEC'ism). And the AIG model of "hyper-evolution" is just plain nonsense that no one would arrive at by a study of the evidence. It is the simple result of a final realization that evolution does take place added to a desperate need to explain the vast array of variation since the time of a supposed from 4,000 years ago.

Begrudging and belated acceptance of a scientific process added to a desperate need to now squeeze that process into a time frame rising wholly out of a particular interpretation of Scripture does not make for a sound scientific theory.

 

[mark kennedy]

I am very disappointed in your response Mark. I feel you are being evasive.

For example, you negelected this question entirely:

And this:
You said:
" If you have a tall plant crossed with a short one and they yeild only tall plants the tall plant genes are said to be dominant while the short ones are called recessive. When analyzing genetic crosses, the first generation is the parental generation, or P1, the second generation is the first filial generation, or F1; the net generation is the second filial generation, or F2 and so on. "

Correct. Now how does this relate to the H-W equilibrium? And the genotypes of P1, F1, F2 and future generations?

H-W is just a baseline for no evolutionary change. There will allways be a certain number of changes but I think the H-W formula only allows for two allele which really doesn't happen very much.

You said:

"The phenotype describes the outward expression of an allele combination."

And what does that imply for the genotype of an organism showing a dominant trait as compared to the genotype of an organism showing a recessive trait?

Mendel had this to say about the masked trait of the recessive by the dominant:

"In the case of each of the seven crosses the hybrid character resembles that of one of the parental forms so closely that the other either escapes obseration completely or cannot be detected with certainity....The expression 'recessive' has been chosen because the characters thereby disignated withdraw of entirely disappear in the hybrids, but nevertheles reappear unchanged with their progeny." There were 7 traits and 70 hybrid crosses studied.

You asked:

" Distinguish between wild type phenotype and a mutant."

To me the question doesn't make much sense. What is a "wild type phenotype"? How does it differ from a "non-wild type"?

By "mutant" do you mean a genetic change or a phenotypic change?

An organism's appearance doen not always reveal its alleles. A wild type phenotype is the most common expression of a particular gene i a population. A mutant phenotype is a variant of a gene's expression that arises when the gene undergoes a change, thus a mutaion. These are standard Mendelian terms.

No, it doesn't. All it shows is that evolution happens. And that is sufficient to show the common ancestry of the species involved. That is why creationists can agree that a certain amount of evolution happens---though they like to hide that admission under terms like variation or adaptation.

But universal common ancestry is implied--unless one can point to species or groups of species that cannot be so related. Or discover a mechanism whereby a parental species cannot become a grandparental species.

For one thing an individual with two identical alleles for a gene is homozygous for that gene. An individual with two different alleles is heterozygous. Basicly a hybrid is heterozygous.

For another thing did you miss the fact that the recessive traits disappear in the hybrid but reappear unchanged in their progeny? Actually the creationist would have to admit a radical amount of variation or adaptation do to the restrictive timeline.

My dear, I am dumbfounded how this has escaped your attention. If I accept the working definition for biological evolution being the change of gene frequencies in populations over time and further the definition of species as members of a population that interbreed and produce fertile offspring. Doesn't that leave me with an enormous task of qualifying radical evolutionary paths? Am I not left with many of the same problems as the Darwinian, in fact, it would leave me no recourse but to accept evolution?

Well, it makes sense to me. Especially as all biological evidence points in that direction.
I know we don't have a way to generate a species by species lineage for every living organism. We never will. But we have enough that I would need some pretty solid disconfirming evidence to reject the thesis of a universal common ancestor.

I think I have made a pretty interesting point that brings out the problems for both the creationist position and the ones of the common ancestor model. The ubiquitious common ancestor model is clearly based on a metaphysical premise since it applies to all biologic living systems descending from some kind of a protoorganism which is incomprehensible from a YEC time frame. I think the Medelian laws of inheritance pose major problems for both points of view. I think the real truth lies somewhere in the middle ground here.

 

[Jet Black]

I just asked if the Mendel laws of inheritance could measure a transitional mutation. The answer would be of course it does.

que? measure? transitional mutation? exqueeze me?

 

[mark kennedy]

que? measure? transitional mutation? exqueeze me?

How many of these microevolutionary changes add up to macroevolution? There is actually a very simple answer to it that even the most militant creationist would have to accept. Unless of course we leave the term species undefined.

 

[Vance]

Well, since micro just means small and macro just means large, it would be enough to make a "large" change. But since scientists don't talk about a measure of micro v. macro, then I would find it very interesting to hear your answer.

Remember, the evolutionary scientist does not draw a line between micro and macro and say "hey, look, we just passed from micro to macro!". These are just general categories to talk about small changes and big changes in the SAME process. There is no need to draw such a line because it is not a significant issue. It is all just evolutionary change on a continuous spectrum. It is only the Creationist who wants to make these two concepts distinct and identifiable so that they can acknowledge that one happens, while still denying the other does.

 

[Jet Black]

How many of these microevolutionary changes add up to macroevolution? There is actually a very simple answer to it that even the most militant creationist would have to accept. Unless of course we leave the term species undefined.

well if we are defining macroevolution as the formation of a new species, where a species is a population that can breed and produce viable, fertile offspring (ignoring those members that are for some mutational reason infertile, like for example those that are just unable to produce sperm) regardless of other differences, then the minimum number of required mutations is 2.


but then you know the definition of species is fuzzy anyway, because life is fuzzy, and there is significant variation within populations. this is the problem with talking to you, you are too obsessed with all these semantic issues and metaphysical things that you like to insert, rather than getting down to the actual nitty gritty of what is going on. I don't really feel like debating with you unless you show some willingness to learn more and reduce the elementary mistakes that you make.

and what is this about mendel's laws measuring things?

 

[mark kennedy]

well if we are defining macroevolution as the formation of a new species, where a species is a population that can breed and produce viable, fertile offspring (ignoring those members that are for some mutational reason infertile, like for example those that are just unable to produce sperm) regardless of other differences, then the minimum number of required mutations is 2.

You do realize that dispite the mutations is say hybrids there is a strong tendancy to revert back right?

but then you know the definition of species is fuzzy anyway, because life is fuzzy, and there is significant variation within populations. this is the problem with talking to you, you are too obsessed with all these semantic issues and metaphysical things that you like to insert, rather than getting down to the actual nitty gritty of what is going on. I don't really feel like debating with you unless you show some willingness to learn more and reduce the elementary mistakes that you make.

and what is this about mendel's laws measuring things?

I simply made the point that the term does have a pretty good working definition but there are allways exceptions to a rule in natural science. I just think calling the essense of the term 'undiscoverable' is silly. Now a comprehesive definition for the term is absolutly essential and it is very much a part of the nitty gritty.

Mendel's laws do measure changes in hybrids and I thought there would be more interest in its signifigance in macroevolution. Mendel's laws measure changes in hybrids, I don't know how it could be any clearer then that. I simply asked if Mendelian genetics measure changes in the gene frequencies and made a point of the tendancy to revert back. I have no idea why this has gotten to be such a bone of contention, it seemed pretty straight forward to me.

 

[Jet Black]

You do realize that dispite the mutations is say hybrids there is a strong tendancy to revert back right?

sorry that made no grammatical sense.

I simply made the point that the term does have a pretty good working definition but there are allways exceptions to a rule in natural science. I just think calling the essense of the term 'undiscoverable' is silly. Now a comprehesive definition for the term is absolutly essential and it is very much a part of the nitty gritty.

Why is a comprehensive definition absolutely nescessary? we know full well that biology is fuzzy - so what is the desparation to fit it into a clear box? There are so many problems with attempting to box things like that, because I can tell you know, you will find a grey area to pretty much any definition you come across - if you try that there will always be things on the borderline. It would be like trying to come up with a comprehensive definition for "red". I mean, would you deal with only monochromatic light or colorimetric coordinates. where is the defference between red and deep orange. where is the difference between deep orange and medium orange orange and yellow.

Mendel's laws do measure changes in hybrids and I thought there would be more interest in its signifigance in macroevolution. Mendel's laws measure changes in hybrids, I don't know how it could be any clearer then that. I simply asked if Mendelian genetics measure changes in the gene frequencies and made a point of the tendancy to revert back. I have no idea why this has gotten to be such a bone of contention, it seemed pretty straight forward to me.

Mendel's "laws" are actually pretty faulty anyway because of pleiotropy and variable gene expression. for example I have a genetic disorder (autosomal dominant), but I only display a couple of symptoms of it. Other people show far more symptoms, such as my mother, brother and niece, but others show even less symptoms such as my other brother and his daughters. so mendelian laws break down in cases like me - because while the gene is inherited in the normal way, the phenotypical expression is not simple. Mendel's laws were interesting at the time, as they showed the particulate nature of inheritance, rather than a blended nature, but that is all they can really be used for. In terms of looking at anything remotely complex they suck a bit really. I still don't get how you could measure anything with them, though you can use them to look at simple cases I suppose.

 

[gluadys]

H-W is just a baseline for no evolutionary change. There will allways be a certain number of changes but I think the H-W formula only allows for two allele which really doesn't happen very much.

Mark, this is a ridiculously inadequate answer to my questions. That makes this the third time of asking and I would request that you really answer them one by one.


1. Do you understand and agree that a 3:1 ratio in phenotype implies a 1:1 ratio in alleles?

2. Do you agree Mendels' work was based primarily on crossing two varieties which bred pure for the trait(s) he was testing, e.g. smooth or wrinked skin, yellow or green seed colour, etc.

2a. What does that imply for the genotype of P1 generation?


3. How does dominance and recessiveness produce the H-W equilibrium in the F1, F2 and subsequent generations?

3a. What does dominance and recessiveness imply about the possible genotypes of organisms showing dominant and recessive traits?


4. What if Mendel had decided to impose a selective pressure on his test subjects? How would he exert a selective pressure in favour of a dominant trait? What would be the expected result in the next two-three generations? How would this differ if he exerted a selective pressure in favour of a recessive trait?

An organism's appearance doen not always reveal its alleles. A wild type phenotype is the most common expression of a particular gene i a population. A mutant phenotype is a variant of a gene's expression that arises when the gene undergoes a change, thus a mutaion. These are standard Mendelian terms.

OK. So you are talking phenotype, not genotype. And "wild-type" means "most common" while any other phenotype is a "mutant"? So what would be the problem with identification? Count the phenotypes. The most common one is the wild-type.

For one thing an individual with two identical alleles for a gene is homozygous for that gene. An individual with two different alleles is heterozygous. Basicly a hybrid is heterozygous.

yep.

For another thing did you miss the fact that the recessive traits disappear in the hybrid but reappear unchanged in their progeny?

Not at all. You had me wondering if you knew that. Your failure to answer my questions above, ----which I do hope you will answer directly this time---continued to imply that you were ignorant of this fact.

Actually the creationist would have to admit a radical amount of variation or adaptation do to the restrictive timeline.

In other words --a radical amount of evolution. Yes, that's obvious. And a genuine problem for YEC. It's a bit like the starlight problem.

Am I not left with many of the same problems as the Darwinian, in fact, it would leave me no recourse but to accept evolution?

No, you have a problem the Darwinian does not have, even accepting evolution, as you must cram an enormous amount of evolution into a restricted time frame of only 4,000 years, yet have it be unnoticeable during most of that period. Evolution does not have that problem at all. Even the relatively rapid evolution of a punctuated equilibrium is not that rapid.

I think I have made a pretty interesting point that brings out the problems for both the creationist position and the ones of the common ancestor model.

I don't see the problems as being comparable.

The ubiquitious common ancestor model is clearly based on a metaphysical premise since it applies to all biologic living systems descending from some kind of a protoorganism which is incomprehensible from a YEC time frame.

Of course, it is incomprehensible within a YEC time frame.
But you are mistaking the basis of universal common descent within the Darwinian framework.

It is not a metaphysical premise. It is not a premise of any sort. It is a logical deduction from more limited instances of common descent, and a deduction which is supported by several lines of objective evidence.

I think the Medelian laws of inheritance pose major problems for both points of view. I think the real truth lies somewhere in the middle ground here.

And I think this conclusion is based on the misapprehension noted in the last paragraph.

 

[gluadys]

How many of these microevolutionary changes add up to macroevolution? There is actually a very simple answer to it that even the most militant creationist would have to accept. Unless of course we leave the term species undefined.

There is no simple answer. It could be as few as one (e.g. nylon bug) or as many as several thousand, depending on the circumstances.

 

[Vance]

"The ubiquitious common ancestor model is clearly based on a metaphysical premise since it applies to all biologic living systems descending from some kind of a protoorganism which is incomprehensible from a YEC time frame."


Aha, now we have it. Your entire opposition to the concepts we are discussing is based ultimately on its inconsistency with your literal reading of Scripture rather than on objective scientific analysis.

 

[gluadys]

You do realize that dispite the mutations is say hybrids there is a strong tendancy to revert back right?

No, I don't.

In the first place, Mendel's hybrids did not involve mutations, but already existing alleles.

Not that it would make any difference if one used a new allelic mutation.

But what I see in Mendel's work is the conclusion that there is not a strong tendency to revert back to the P1 genotypes. Mendel's work is the basis of the H-W equilibirum, which states that, all things being equal, the rate of hybridization will remain constant, and there will be no reversion to type.

How do you get such a different conclusion?

 

[mark kennedy]

Mark, this is a ridiculously inadequate answer to my questions. That makes this the third time of asking and I would request that you really answer them one by one.


1. Do you understand and agree that a 3:1 ratio in phenotype implies a 1:1 ratio in alleles?

2. Do you agree Mendels' work was based primarily on crossing two varieties which bred pure for the trait(s) he was testing, e.g. smooth or wrinked skin, yellow or green seed colour, etc.

2a. What does that imply for the genotype of P1 generation?


3. How does dominance and recessiveness produce the H-W equilibrium in the F1, F2 and subsequent generations?

3a. What does dominance and recessiveness imply about the possible genotypes of organisms showing dominant and recessive traits?


4. What if Mendel had decided to impose a selective pressure on his test subjects? How would he exert a selective pressure in favour of a dominant trait? What would be the expected result in the next two-three generations? How would this differ if he exerted a selective pressure in favour of a recessive trait?

I'm not sure where you are getting the 1:1 ratio of alleles or what your point is. Further I don't have a clue what kind of an implication you see in explicitly demonstrated hybrid peas on possible genotypes. This isnt about implicite possibilities but explicitly demonstrated hybrids reduced to mathmatical ratios. Now H-W equilibrium is when there is no selected presure, natural selection,migration and only two alleles. Why would Mendel want to get to H-W equilibrium while crossing hybrids.

It is a little disturbing that a relativly minor point can get turned into a major issue. Mendel's laws wouldn't even address the long term changes in things like bones and brain sizes in mammals. It would seem that all a creationist has to be is a creationist to be wrong on here.

 

[Vance]

Another point about this, ultimately revealing, quote:

"The ubiquitious common ancestor model is clearly based on a metaphysical premise since it applies to all biologic living systems descending from some kind of a protoorganism which is incomprehensible from a YEC time frame."

What you are saying is that you believe science has come to a conclusion based on a metaphysical premise which is wrong because it is contrary to your theological premise. All you are doing by this twist is attempting to reduce scientific conclusions to the same playing field as "science by theology" as presented by YEC'ism. This then allows YEC'ers the comfort of saying they are just choosing between "belief systems" and obviously are choosing the correct one. And, further, they can preach the idea that evolution is as much a "religion" as YEC'ism.

This, of course, is just bunk. The theory of common descent is simply a logical and supportable conclusion based on all the know about how evolution works. It is not based on some "metaphysical" presumption, but is reached just as any other scientific theory is reached: it is the conclusion that best fits the evidence. AND, in this case, it so overwhelmingly fits the evidence that only those who do, indeed, have theological reasons to dispute take issue with it. While one aspect or another of evolutionary processes are constantly being debated (as in any scientific field), the only scientists who seriously dispute the reality of common descent are those with religious objections.

Here is a question for you. Your statement I quoted seems to be saying that if you were convinced that the earth was, indeed, billions of years old, you would then accept common descent. Is this true?

 

[mark kennedy]

This, of course, is just bunk. The theory of common descent is simply a logical and supportable conclusion based on all the know about how evolution works. It is not based on some "metaphysical" presumption, but is reached just as any other scientific theory is reached: it is the conclusion that best fits the evidence. AND, in this case, it so overwhelmingly fits the evidence that only those who do, indeed, have theological reasons to dispute take issue with it. While one aspect or another of evolutionary processes are constantly being debated (as in any scientific field), the only scientists who seriously dispute the reality of common descent are those with religious objections.

Here is a question for you. Your statement I quoted seems to be saying that if you were convinced that the earth was, indeed, billions of years old, you would then accept common descent. Is this true?

I am not convinced that anything ever descended from a single cell protoorganism and timelines are of very little consequence. Now as far as evolutionary thought being metaphysics I thought the quote by a famous evolutionary biologist explained what I meant by that. Now my theology is also of very little consequence when thinking about evolutionary biology, if I became a died in the wool atheist I would not embrace gradualism. It just doesnt fit the facts.

I went some 25 pages defending my concept that evolution is metaphysics and for some reason no evolutionist would even consider it. Evolution is far more then the changing of genes in populations over time, it engulfs all of natural science and is not shy about making claims against theistic reasoning. Thats why the term 'species' has to be kept 'undiscoverable' and fuzzy, there can't be any limits placed on a metaphysical premise.

 

[Vance]

Ah, then you hold to the "conspiracy" theory about evolution. This is just wrong-headed. Evolutionary theory is a basic element of many strains of science because it is SUPPORTED by the evidence of many strains of science. There are simply no metaphysics involved. Scientists do not believe in evolutionary theory because it fits into so some philosophical framework for them (as YEC's do with their psuedo-scientific conclusions). They believe in evolutionary theory because it works and is vastly supported by the evidence. It has more scientific support than the theory of gravity.

You are also mistaken when you say that evolution "is not shy about making claims against theistic reasoning". There may be individual scientists who do this, but not "evolution" itself, nor the scientific community as a whole.

I understand that it is infinitely more comforting for YEC's to believe that the scientific community believes in evolution based ultimately on some philosophical underpinnings that are contrary to theistic beliefs. If this is NOT true, then YEC's are faced with the prospect that 99.9% of the scientists in the relevant fields believe in common descent based simply on the scientific evidence.

Understandable, but still wrong.