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#1 PhilC

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Posted 07 July 2010 - 03:20 PM

The following example is being used for illustrative purposes only. I’ve been trying to think of a hook to hang this explanation on. Once the concept is grasped, then other examples can be sought.

Our foramen magnum (the hole where the spine joins the skull) is in a different place to an apes. We have ours in the place it is to enable us to have our skull correctly placed when walking upright. Our foramen magnum is placed at the bottom of the skull, an apes at the back. At some point in our evolutionary history that hole must have moved from the back to the bottom.

The creationist viewpoint is that mutations must have caused this change as if the genes have a blueprint which “knows” where the hole is and each mutation moves it slightly further round. It is inconceivable, creationists claim, that as human evolution occurred the right mutations would appear to push the foramen magnum round at the same time that other mutations would be helping bipedality and brain size etc. and I would agree with them. Once again, we have evolutionists and creationists saying the same thing but with creationists saying that this shows evolution couldn’t have occurred. Once again, when the actual evidence is examined then the picture becomes clearer.

Our DNA is not a blueprint, that is the first misconception that has to be removed. Let me use this analogy: DNA does not map a body in the way that a blueprint does. When humans construct a building, they work from a blueprint. Any worker on the site may see the blueprints and see how what he/she has to accomplish to asisst the construction. Termites also construct buildings, we call them mounds, which have complex air conditioning systems and tunnels which we would require a blueprint to accomplish. In fact each termite does not know what it is building, it is just following simple, local rules. When all the termites do this, we see the mound appearing.

To make any feature in the embryo during development then certain genes are switched on and off in certain places. The technical details need not concern us here (but I can explain in more detail if requested, but I would recommend the book ‘The Art of Genes – How Organisms Build Themselves’ for a detailed but readable account with an analogy that is hard to beat) but in effect there is a certain set of proteins in the body that are expressed at different points and the genes for making the foramen magnum will respond to that background set of proteins and be switched on at the right place to make this.

There will be variation in the area that these genes will be expressed, so that the foramen magnum will not be perfectly placed each time. Imagine that (in a two dimensional plain) the perfect place for an ape is x,y. There will be genes in the naturally occuring population that express the gene there and also at x+1,y+1; x-1,y and all other combinations. This is controlled by the genes but not as a blueprint just as an area of expression. As bipedality progressed, any variation in the position of the foramen magnum to assist would be selected for, so that the genes for (for example) x+1,y will be selected for. Notice that this is a relative position. When an embryo is formed it will express genes close to x,y but with an x+1 gene in place, the foramen magnum will move slightly. In the next generation, its children will have a slighly displaced x,y from their grandparents but may also have an x+1 gene passed to them.

In other words there would be selection pressure to move the area if expression to the base of the skull. No mutation is required. No gain of information and no loss of information is necessary. Over time we would see the foramen magnum move position but not a single mutation would be required. The only requirement at this level of discussion is that there is an area of the embryo that expresses the genes which make the foramen magnum and that this area varies slightly in position.

Once the foramen magnum is in the right position, genes for x,y exactly will be selected for. The genes for relative positions away from gthere will still exist in the population but will be selected against, so the position will not change. There will be a tiny drift around x,y but it will not drift far before selection pushes it back. There will, in effect, be negative feedback controlling the position of the foramen magnum.

When creationists argue that there are not enough mutations to change an ape into a human, they are missing the point. The number of mutations required if DNA was a blueprint would be huge and using that idea as a starting point I would support them and I would drop evolution from my paradigm.

Think about the size of our brain compared with a chimp’s (or Lucy’s, which is about the same size). The size of each area of the brain is also controlled by the expression of genes based on a backdrop of proteins. For a larger brain to grow, the areas of expression just need to be enlarged slightly (at embryonic level if one more cell expresses something then that will increase the size of that thing in the adult by a much larger amount). No mutations are required to achieve this, just a slight variation in the area that the gene is expressed in.

#2 PhilC

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Posted 15 July 2010 - 05:01 AM

Actually, the example may be a bad ine:

Here is the underside of the modern human cranium. Here is the underside of a gorilla or a chimpanzee cranium. Here is the underside of a mouse cranium. Here’s the foramen magnum, way at the back of this wild mouse. Here’s the foramen magnum in the chimp, further back. Here’s the foramen magnum in us. It’s further forward.

[31:37] Now, it just happens that there is a knock out mouse. Here is the cranial base of the neonatal mouse. There is the foramen magnum at the back. This is the wild type. Here’s the nose end and that is the back end. Here is this knock out mouse. The foramen magnum, instead of being right at the back and facing backwards has migrated forwards and faces more downward.

[31:59] This discovery was entirely accidental. These mice are used by people who are interested in striated muscle tumors. They use them as a model of the striated muscle tumors in human children. But it just happens that not only do they have a high incidence of striated muscle tumors but they also have this reorganized cranial base.

[32:19] It doesn’t interfere with the mice very much. They seem to do fine. So the point about this is that you can have quite large reorganizations with a relatively simple genetic basis. I’m not claiming that the genes involved in this mouse are the genes involved in the difference between chimpanzees and modern humans, but I am claiming that it’s not such a big deal as one would think it might be.


http://www.darwin.as...pts/05_wood.php

Large morphological change not affecting the mice with simple genetic change.

#3 PhilC

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Posted 19 July 2010 - 05:11 AM

The foramen magnum example obviously isn’t a great one, because as shown a single gene can cause a large morphological change but without any deleterious effects. Here is another example which ties in with the embryological development thread and brings these two together:

This will eventually allow us to understand why there is this genetic variation within a single population. Our guess is that the significant genetic variation doesn't lie in Bmp4 exactly; we think that Bmp4 is probably very structurally similar amongst the species, but it's in the whole complex regulatory apparatus governing the expression of this gene; that core ingredient resulting in different adult sizes, lies in the regulation rather than the gene itself.


Peter Grant

The changes in the expression are not going to show up like mutations will and this is the reason why we do not expect to know every change that occurs. It comes back to the fact that DNA is not a blueprint.

This ties in with the thread on embryology:

http://www.evolution...?showtopic=3527

which shows how the change in expression occurs.

#4 gilbo12345

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Posted 21 July 2010 - 11:08 PM

The following example is being used for illustrative purposes only.  I’ve been trying to think of a hook to hang this explanation on.  Once the concept is grasped, then other examples can be sought.

Our foramen magnum (the hole where the spine joins the skull) is in a different place to an apes.  We have ours in the place it is to enable us to have our skull correctly placed when walking upright.  Our foramen magnum is placed at the bottom of the skull, an apes at the back.  At some point in our evolutionary history that hole must have moved from the back to the bottom.

The creationist viewpoint is that mutations must have caused this change as if the genes have a blueprint which “knows” where the hole is and each mutation moves it slightly further round.  It is inconceivable, creationists claim, that as human evolution occurred the right mutations would appear to push the foramen magnum round at the same time that other mutations would be helping bipedality and brain size etc. and I would agree with them.  Once again, we have evolutionists and creationists saying the same thing but with creationists saying that this shows evolution couldn’t have occurred.  Once again, when the actual evidence is examined then the picture becomes clearer.

Our DNA is not a blueprint, that is the first misconception that has to be removed.  Let me use this analogy: DNA does not map a body in the way that a blueprint does.  When humans construct a building, they work from a blueprint.  Any worker on the site may see the blueprints and see how what he/she has to accomplish to asisst the construction.  Termites also construct buildings, we call them mounds, which have  complex air conditioning systems and tunnels which we would require a blueprint to accomplish. In fact each termite does not know what it is building, it is just following simple, local rules.  When all the termites do this, we see the mound appearing.

To make any feature in the embryo during development then certain genes are switched on and off in certain places.  The technical details need not concern us here (but I can explain in more detail if requested, but I would recommend the book ‘The Art of Genes – How Organisms Build Themselves’ for a detailed but readable account with an analogy that is hard to beat) but in  effect there is a certain set of proteins in the body that are expressed at different points and the genes for making the foramen magnum will respond to that background set of proteins and be switched on at the right place to make this.

There will be variation in the  area that these genes will be expressed, so that the foramen magnum will not be perfectly placed each time.  Imagine that (in a two dimensional plain) the perfect place for an ape is x,y.  There will be genes in the naturally occuring population that express the gene there and also at x+1,y+1; x-1,y and all other combinations.  This is controlled by the genes but not as a blueprint just as an area of expression.  As bipedality progressed, any variation in the position of the foramen magnum to assist would be selected for, so that the genes for (for example) x+1,y will be selected for.  Notice that this is a relative position.  When an embryo is formed it will express genes close to x,y but with an x+1 gene in place, the foramen magnum will move slightly.  In the next generation, its children will have a slighly displaced x,y from their grandparents but may also have an x+1 gene passed to them.

In other words there would be selection pressure to move the area if expression to the base of the skull.  No mutation is required.  No gain of information and no loss of information is necessary. Over time we would see the foramen magnum move position but not a single mutation would be required.  The only requirement at this level of discussion is that there is an area of the embryo that expresses the genes which make the foramen magnum and that this area varies slightly in position.

Once the foramen magnum is  in the right position, genes for x,y exactly will be selected for. The genes for relative positions away from gthere will still exist in the population but will be selected against, so the position will not change. There will be a tiny drift around x,y but it will not drift far before selection pushes it back.  There will, in effect, be negative feedback controlling the position of the foramen magnum.

When creationists argue that there are not enough mutations to change an ape into a human, they are missing the point.  The number of mutations required if DNA was a blueprint would be huge and using that idea as a starting point I would support them and I would drop evolution from my paradigm.

Think about the size of our brain compared with a chimp’s (or Lucy’s, which is about the same size).  The size of each area of the brain is also controlled by the expression of genes based on a backdrop of proteins.  For a larger brain to grow, the areas of expression just need to be enlarged slightly (at embryonic level if one more cell expresses something then that will increase the size of that thing in the adult by a much larger amount).  No mutations are required to achieve this, just a slight variation in the area that the gene is expressed in.

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I didn't think assumptions could be used as evidence Phil. Do you have observed evidence for this process in variation?

What we observe in nature, (in reality), that yes some change in size and shape can occur.. Like I am taller than my Dad.. However we are still built to the same specifications, ie 2 eyes, one head, 2 legs, 2 arms, etc etc... What we see is that variation is ALWAYS limited to the genome that codes for the organisms production. Would you expect a leg to grow on a fish, if the fish DNA didn't code for it? No, so before any of your supposed changes need to happen, there needs to be a change in the code.

The evolutionary hypothesis on this, (NOT CREATIONIST!) is...

"that mutations must have caused this change as if the genes have a blueprint which “knows” where the hole is and each mutation moves it slightly further round"

Evolutionists assume that over millions of years mutations caused enough changes to the genetic code to code for a completely new form of the organism.. ie- legged fish, upright walking simian ancestors, etc...

I think what you are trying to do here, (but unsuccesfully) is to show that mutations are not needed for evolution to happen. As you probably have an inkling that mutations are not the way to go for evolution...

However you must realise that there are no changes to an organism, unless it is coded for... If it didn't come down to DNA to correctly code for an organisms development then all kinds of changes could occur as there is no plan of design to follow... However the fact remains to this day that the majority of babies born in all species show no signs of changes from the original design process of that creature.. Meaning that a change needs to occur in the code that is the template for each organisms design.

#5 PhilC

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Posted 22 July 2010 - 12:51 AM

Read the whole thread. I show why my original post doesn't work and then I show an example where it does, where change in expression changes an organism.

#6 PhilC

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Posted 22 July 2010 - 12:57 AM

"that mutations must have caused this change as if the genes have a blueprint which “knows” where the hole is and each mutation moves it slightly further round"


No! That is exactly wrong. Did you read my point aboit selection pressure?

In the example that I know has another possible method (in the fact that a mutation is known to cause this very change!) but which still works as a tallking point to highlight the ideas behind it, the process would be going on as we began to walk upright. If we were starting to walk upright then there would be selection pressure to move the foramen magnum.

This thread should be read in conjunction with:


http://www.evolution...?showtopic=3527

#7 gilbo12345

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Posted 22 July 2010 - 01:03 AM

No! That is exactly wrong. Did you read my point aboit selection pressure?

In the example that I know has another possible method (in the fact that a mutation is known to cause this very change!) but which still works as a tallking point to highlight the ideas behind it, the process would be going on as we began to walk upright. If we were starting to walk upright then there would be selection pressure to move the foramen magnum.

This thread should be read in conjunction with:
http://www.evolution...?showtopic=3527

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But how do you suppose we started to walk upright, if not by mutations... (Check out Mendels 2nd Law)

#8 PhilC

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Posted 22 July 2010 - 02:24 AM

Read the post about embryology that I mentioned above. Mendel isn't the be all and end all of how inheritaance happens. WE know so much more about the way bodies build themselves.

The level of specificity of a protein to a stretch of DNA can change without an actual mutation. This will affect the wy that a body is built without leaving a genetic trace.

Yes, this has been observed. The thing Darwin said and which evolutionists keep saying but which creationists keep ignoring is that variation is the key thing to follow. Creationists have what I call a mutation fixation.

Some proteins can be changed in structure without a change in the genes that make them. The same amino acid sequence but a different way of them coiling together. This can affect the embryo, but you will never find the mutation that caused this.

#9 gilbo12345

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Posted 22 July 2010 - 02:34 AM

Read the post about embryology that I mentioned above. Mendel isn't the be all and end all of how inheritaance happens. WE know so much more about the way bodies build themselves.

The level of specificity of a protein to a stretch of DNA can change without an actual mutation. This will affect the wy that a body is built without leaving a genetic trace.

Yes, this has been observed. The thing Darwin said and which evolutionists keep saying but which creationists keep ignoring is that variation is the key thing to follow. Creationists have what I call a mutation fixation.

Some proteins can be changed in structure without a change in the genes that make them. The same amino acid sequence but a different way of them coiling together. This can affect the embryo, but you will never find the mutation that caused this.

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Variation has been observed, but it is only to the extent that is applicable to Mendels LAWS... This is the difference to the accepted micro-evolution, (variation), and the imaginary macro-evolution, which evolutionists believe happened.. I believe this was covered when you first started posting on this site.

Variation is not evidence of evolution

And in the end,the proteins come about by way of DNA, hence it is attributed to the genetic code, yes it is the plan by which all things develop and grow. Yes it is a design template.


EDIT: How do proteins change without genes to facilitate a change? denaturation perhaps? :rolleyes:

Besides I showed earlier in the other thread how a change from the norm, for a proteins function will (with 99.9% accuracy), cause a defect or loss in fitness... As the cell is creating the protein to fulfill a specific function... As specific chemicals cause specific activators to activate, which specifically create the specific protein to fulfill a spceific function.. However any change in the function means it is not doing what the cell wants it to do and the ability of that function is lost.... (Like I showed with the lactase inhibitor example, which lead to a decrease in fitness and eventually death of the cell)

#10 PhilC

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Posted 22 July 2010 - 03:42 AM

Variation has been observed, but it is only to the extent that is applicable to Mendels LAWS... This is the difference to the accepted micro-evolution, (variation), and the imaginary macro-evolution, which evolutionists believe happened.. I believe this was covered when you first started posting on this site.

Variation is not evidence of evolution


I agree, variation is not evidence of evolution, but variation is what evolution worksw on. This is Darwinism 101.

I have shown that some things (like the expression of BMP4) affect the organism but not through a mutation.

Mendelian inheritance also doesn't work with mitochindrial DNA or cytoplasmic inheritance. Mendel's laws are specific to types of inheritance.

And in the end,the proteins come about by way of DNA, hence it is attributed to the genetic code, yes it is the plan by which all things develop and grow. Yes it is a design template.


Read up on the Homeobox genes and read the analogy of the terrmite mound in the embryology thread. The termites only follow local rules but create a mqagnificent habitation. There is no design template for the termite mound at all.

EDIT: How do proteins change without genes to facilitate a change? denaturation perhaps? 


It's all to do with their final coiling after the amino acids have been put together, I'm a bit rusty on the details but its to do with the many ways that the hydrogen bonds can connect plus the hyrdophilicity and hydrophobicity (if they are even words!) of different amino acids.

Besides I showed earlier in the other thread how a change from the norm, for a proteins function will (with 99.9% accuracy), cause a defect or loss in fitness... As the cell is creating the protein to fulfill a specific function... As specific chemicals cause specific activators to activate, which specifically create the specific protein to fulfill a spceific function.. However any change in the function means it is not doing what the cell wants it to do and the ability of that function is lost.... (Like I showed with the lactase inhibitor example, which lead to a decrease in fitness and eventually death of the cell)


Yes, but you don't consder the observed gene duplication as I discussed. If a protein A does Y and is copied then its copy B also does Y. If B now changes, Y still occurs and B can change and it may start doing Z.

The olfactory genes are a prime example, but I've said this before.

#11 gilbo12345

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Posted 22 July 2010 - 06:32 AM

Read up on the Homeobox genes and read the analogy of the terrmite mound in the embryology thread. The termites only follow local rules but create a mqagnificent habitation. There is no design template for the termite mound at all.


The olfactory genes are a prime example, but I've said this before.

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Yet I bet if you look at multiple termite mounds, they won't look the same....

Which is my point. If there is no template for the organism to get instructions from then we should see babies being born with arms from their head and 3 legs...etc. If there is no template / instructions to follow, how can you assume that the development process will run as it is meant to, rather than being a total mess? (since there is no direction from the template)

Here is a scientific experiment you can do. Get 1000 bacterial cells, take out their DNA and watch them replicate. I mean if they don't need DNA to be the instructions, to be the guide, then they should replicate just fine...

Or you can go further and get a sperm and an egg and remove the DNA from them and watch them grow into a baby...

I am serious, this is what it sounds like you are insisting upon. Hence we need DNA as the template for development. If it isn't coded for, (like an arm or leg or whatever) then it will not appear.

#12 gilbo12345

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Posted 22 July 2010 - 06:34 AM

Yes, but you don't consder the observed gene duplication as I discussed. If a protein A does Y and is copied then its copy B also does Y. If B now changes, Y still occurs and B can change and it may start doing Z.

The olfactory genes are a prime example, but I've said this before.

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Not ALL systems are redundant, most are vital. I have already had this talk with 2 of my Biology lectuers, and I am telling you what they told me.

#13 PhilC

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Posted 22 July 2010 - 06:50 AM

I'd agree which is why gene duplication is so important. If there is only one gene for lactase then if that is damaged then the organism will die. Natural selection will select against this mutation.

If the lactase gene duplicates then one of those genes can change without affecting the non-redundancy of the lactase gene. In effect gene duplication builds redundancy.

Look at the olfactory genes.

#14 PhilC

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Posted 22 July 2010 - 06:51 AM

Which is my point. If there is no template for the organism to get instructions from then we should see babies being born with arms from their head and 3 legs...etc. If there is no template / instructions to follow, how can you assume that the development process will run as it is meant to, rather than being a total mess? (since there is no direction from the template)


Read my embryology thread and read this one in conjunction with it. A lot of evidence is multithreaded.




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