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Author Topic:   How creationism explains babies with tails
Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 11 of 59 (596254)
12-14-2010 1:13 AM


I haven't looked into the genetic reason for human tail mutations yet, but I have a quick comment.

My son was born with 7 toes on each foot.

What aspect of his evolutionary past was creeping up?

He had also had an extra bone growth coming from just above his wrist.

Did our ape ancestors have extra digits too?

I think you can read into genetic mutations what you want, but its not really proof of anything.


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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 14 of 59 (596261)
12-14-2010 2:59 AM
Reply to: Message 13 by crashfrog
12-14-2010 2:28 AM


"Maybe next time, though, wash the turkey baster first?"

Amusing...

I didn't even mention his webbed toes - that must have been from his frog ancestor.

Edited by Aaron, : No reason given.

Edited by Aaron, : No reason given.


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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


(1)
Message 19 of 59 (596480)
12-15-2010 2:31 AM
Reply to: Message 15 by Granny Magda
12-14-2010 5:39 AM


Re: Polydacty
Granny M,

Thanks for the welcome!

quote:
"If I'm right about that, then the chances are that your son has his extra digits on the "thumb/big toe" side of the feet

Right you are - though they have been removed. I have done a little reading about the sonic hedgehog genes.

quote:
"Mutations in the genes that keep sonic in check can lead to over-expression of certain traits, including fingers and toes."

Exactly, these mutation have nothing to do with evolutionary ancestors. They are merely mutations in regulatory genes. Babies aren't born with tails because of a reversion to an ancestral ape state any more than babies born with Anencephaly - or lack of a spinal chord - are reverting back to a invertebrate ancestor. It's just a genetic mixup, that's all.

quote:
"To me it seems like strong evidence of inter-relatedness. We use the same chemical pathways as cats and pigs, apes and horses in our developmental processes. There would be no reason for this if the Theory of Evolution were not true."

This is a different line of reason than the one that started this thread.

quote:
"This argues very strongly that a designer could have, if he so wished, used very different processes for different mammals. This does not appear to be the case."

The problem with this logic is an assumption that if everything was designed, the designer wouldn't have repeated elements in each creature. You imply that better proof of a designer is if each creature employed unique metabolic pathways, had DNA composed of different types base pairs, or had unique methods of reading DNA. I can see a logical reason for why a designer would use common elements - it allows for a cohesive circle of life where creatures can obtain nutrients by consuming other creatures made of similar building blocks.

If each creature had a totally unique genetic framework with a unique DNA structure - I doubt this would be taken as evidence for a designer - but for evidence that abiogenesis is a simple process that happened many times leading to many unique types of creatures.


This message is a reply to:
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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 20 of 59 (596481)
12-15-2010 2:38 AM
Reply to: Message 15 by Granny Magda
12-14-2010 5:39 AM


Re: Polydacty
quote:
"Our developmental processes are amazing, but they are far from perfect. This is, of course, exactly what we would expect to see from the haphazard business of evolution. It is rather harder to square with the idea of an intelligent designer though."

This is assuming 2 things:

1.) that an intelligent designer must create creatures that are completely perfect and can life forever - and has no reason to do otherwise

2.) that the imperfections we see in development were part of the original design


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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 23 of 59 (596631)
12-16-2010 1:28 AM
Reply to: Message 21 by Granny Magda
12-15-2010 10:57 AM


Re: Polydacty
quote:
"So in summary, human tails do not necessarily reflect a "reversion" to an atavistic state but they do reveal how such a change could have taken place. They do reveal that such changes are, in principle, possible, so they do touch on the ToE."

I agree with your assessment from a logic standpoint.

quote:
"Why need this be true if they are designed from scratch? Why not a human with insect signalling proteins? Why not mix and match, across the board? This is what human designers do after all. But no, we see that variation takes place within a framework of evolutionary relatedness."

Actually, in the realm of human engineering, similar looking cars will use many of the same design and mechanical elements - they are necessary to create a functioning car. A toaster, however, will have far fewer related components. Components determine function. A toaster that is made with a manifold, spark plugs, and fuel filter won't be a handy toaster.

quote:
"Why would God ape evolution?

Please rephrase this, I'm not sure what you are saying.

quote:
"Yes. You are absolutely right. You must assume that the designer wanted his creations to suffer and die. Nice."

Suffering isn't a universal property of life - but even if it were - that's an interesting topic from a theological standpoint that would take this discussion in a whole new direction.

I'll use a simple analogy. What would you think of a rich father who gave his son a 1985 Ford Tempo with 125k for his 16th birthday? A rotten father? What if the father made it known that this car was a test of sorts to see if the son could handle the responsibility. If the son took good care of the car for two years, he would be rewarded with a 2010 Audi R8. This sounds like a good father to me who is more concerned with character building and a future reward rather than providing his son with the perfect car right now.

quote:
"Are you saying that they evolved?"

Evolved... devolved... I'm okay with that.

Our DNA has been mutating and breaking down for a long time. Genetic disease is on the rise, not on the decline.


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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 27 of 59 (597353)
12-21-2010 1:40 AM
Reply to: Message 26 by Granny Magda
12-16-2010 12:51 PM


Re: Polydacty
"Why do we only see the mammalian hedgehog homologues in mammals? A designer could easily have put them in insects. He did not."

Why do you think a designer would put a mammalian protein in an insect?

There are some proteins that are universal to most (if not all) creatures - such as those associated with certain enzymatic reactions.
On the other hand, regulatory proteins are not highly shared.

"Mammals have mammalian hedgehog, insects have their own version. Why not mix-and-match, the way a designer would?"

Do you think there are many proteins that can be swapped back and forth between various creatures without causing harm?

The pieces fit the purpose. If there are a great number of parts that could be swapped back and forth between mammals and insects, you'd think evolution would have conserved more proteins across the board. Why diverge from the common ancestor when there is no need?

Why do humans and chimps only share about 30% of identical protein structures if those proteins perform more or less the same role both each species? What pressure would cause humans to diverge from the protein structure of the common ancestor if the protein performs the same role?

"By the way, what is your explanation for the presence of a tail in the human embryo?"

That might be a better question for a developmental biologist. What purpose does the tail serve in the embryo's development?

As we know, several of the vertebrae fuse together to form the coccyx. The rest are absorbed.
part - why would a body part grow - only to be absorbed? I can't say that I'm a specialist enough to say for sure - but it is not without precedence in embryonic development. In the early stages of brain development, a group of cells help establish boundaries until the proper cells are available - and later the temporary cells disappear. Similarly, the tail end may serve as a place holder until the rest of the body grows around it.

That's my guess at least.

"I will simply say this of your car analogy; for it to work, the father would have to withhold the Audi until after his son died. That is a much fairer comparison to what you are really intimating."

I'm only returning to this point because your rebuttal doesn't quite fit the paradigm I was proposing. Perhaps from an atheistic view of death, the father would be crummy - because death would be dark nonthingness for the son. However, any theistic view of death portrays it as a "graduation" of sorts into a better existence. In this case, the son gets the reward for his trials after "graduation."


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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 28 of 59 (597354)
12-21-2010 1:55 AM
Reply to: Message 25 by Granny Magda
12-16-2010 12:16 PM


Re: We're back to considerations of human tails
"Personally, I don't think that babies being born with tails is quite the evolutionary give-away that it appears to be at first glance. I think that whilst an atavistic explanation might be correct, it might be a simple developmental fluke that creates simple tails, not ancient traits being re-expressed."

I agree - when a baby is born with a tail, it is a far cry from the tail of a monkey.

Anybody know if chimps or gorillas are ever born with accidental tails?

Anyhow, Haeckle's theory of the Biogenetic Law is largely debunked.

""The theory of recapitulation . . should be defunct today."—*Stephen J. Gould, "Dr. Down's Syndrome," Natural History, April 1980, p. 144. "

I read over a long paper about Haeckle's theories - including modern analysis of it. Here's a quote from it:

"Pennisi & Roush (1997) analyse the downfall of
Haeckel's theories, and state that: ` if birds descended
from reptiles, their embryos should show signs of
developing scales before feathers, but that's not so'."

This message is a reply to:
 Message 25 by Granny Magda, posted 12-16-2010 12:16 PM Granny Magda has acknowledged this reply

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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 32 of 59 (598295)
12-30-2010 2:59 AM
Reply to: Message 29 by Granny Magda
12-21-2010 8:06 AM


Re: How Creationism Explains Human Tails (It Doesn't)
"Why do you think a designer would put a mammalian protein in an insect?

Well apart from anything else, it would stop us from looking quite so evolved. It seems perverse that God should create life, only to go to an effort to make it look as though it evolved and that he was never involved. That seems dishonest.

There would be those who would find patterns to support their position no matter what this world looked like. I'm sure you've heard it a million times already, but the evidence for common ancestry could logically be used as evidence for common design.

Do you think there are many proteins that can be swapped back and forth between various creatures without causing harm?

This is God we're talking about isn't it? Why do you suddenly seek to place arbitrary limits upon his capabilities?"

What you are suggesting about God's capabilities is not in line with the historic Christian position of God. God has limits. He can't operate in logically contradictory means. He can't make you exist and not-exist at the same time in the same place in the same way. He can't make a square circle. These limits certainly aren't arbitrary.

If God has decided that protein A B and C will lead to the formation of a backbone - He can't put those same proteins in the same way in an insect and have them lead to the formation of an eye.

The puzzle pieces form the puzzle.

You seem to expect that God should be able to put the same exact pieces in a different puzzle yet have the puzzle look completely different. This isn't a logical possibility.

"So the 30% figure is misleading when mentioned alone, as it fails to note that the average human/chimp protein comparison differs by only two amino acids."

What is amazing is that with so few average differences between homologs, there aren't more identical protein products - what with the redundancy of the base pair code.

This study notes 80% difference between human and chimp proteins. (http://homes.bio.psu.edu/...lty/nei/lab/2005-glazko-etal.pdf)

"What purpose does the tail serve in the embryo's development?

None."

I'd be interested to hear what grounds you have to make such an authoritative statement. I found it difficult to find much research on it whatsoever. Perhaps we don't know the role yet.

"Let's be clear here; you have no real explanation for the embryonic tail. The creationist position cannot explain this feature."

I'll let you know when I'm making a statement for the whole of creationism... Until then - I reserve the right to speculate and make mistakes.

"There is no equivalent for the embryonic tail. It is simply reabsorbed. Nothing grows in its place. This is highly implausible."

There are a number of temporary structures in fetal development that aren't replaced with an identical structure, such as the pronephric kidney and pharyngeal arches. Both serve temporary functions and both are later dissolved.

I read someone suggest that the embryonic tail helps ensure there is adequate blood supply to the developing leg buds.

The tail may also serve as a cell inducer which provides signals to spurn the development of other tissues and structures. This is known to be the case in other organisms such as chickens and frogs whose tail portion helps induce the growth of some of the hind portions. Perhaps the human tail does the same thing and retracts slightly when its job is finished.

The death of the final few vertebrae in the embryonic tail may just be part of the process of forming the coccyx. Similarly, there are interdigital cells that must die during development for our toes and fingers to form correctly. The cells aren't replaced - they are temporary structures.


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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 37 of 59 (599253)
01-06-2011 2:53 AM
Reply to: Message 33 by Granny Magda
12-30-2010 8:30 AM


Re: How Creationism Explains Human Tails (It Doesn't)
"And we call these people "creationists".

Zing!

"Keeping evolutionary changes strictly limited to those taxa in which they originated cannot be used as evidence for anything other than evolution."

I'm not tracking with your thought here - please give an example.

"There is no reason why God, if he can create complex biology, can't produce it however he likes. Certainly he could have created in such a way that did not so perfectly replicate evolution. Face it Aaron, your only option here is to believe in a liar god."

Can't produce it however he likes??? The last time I checked there was more biodiversity on this planet than any person could study in a lifetime - and then some that we don't even know about. With so much variety, there is bound to be creatures that look similar. With creatures that look similar, there's bound to be similar genetic makeup.

A designer could have done it this way.

I'm still not sure what you think the kingdoms of life should look like in order for it to look designed.

"Again, this is not a logical impossibility and the close homologies between mammalian and insect signalling molecules gives the lie to this."

You really are giving me the run-around. First you wondered why mammals and insects don't have genetic cross-over "the way a designer would do it."

"Why not a human with insect signalling proteins? Why not mix and match, across the board?" you said.

I responded by saying that some signalling genes were common across the board.

I'm no master of biology, but I'm wondering about the depths of your understanding. Have you heard of molecular specificity? Proteins perform specific roles and can only interact with other specific proteins. God can't break those rules and use a sequence of proteins to perform one function in a mammal and another function in an insect. The closer the biology of two organisms, the closer their genetic makeup will be - by necessity. That doesn't mean that insects and mammals won't share certain proteins - because they do.

"Creationism cannot explain the human embryonic tail."

You are already settled on your answer - yet how many creationists have you polled? I'm not dismayed if I can't answer you satisfactorily - because I'm not a biologist. Find a creationist biologist and maybe he/she can give you the answer you are looking for.

"This completely misses the point. The tail becomes the coccyx yes, but why a tail in the first place? Why does your all-knowing god not simply design a tail? Why does he seek to deceive us by achieving his design through what looks so clearly like an evolutionary atavism?"

Are you asking why we have a coccyx? I don't quite grasp the point you are trying to make here.

"Great. Bring that evidence. Bring it without the word "perhaps" in it so prominently. You can wonder "what if?" all day, but in the absence of any evidence for these claims, you are whistling in the dark."

I'm trying to do my due diligence. I emailed some developmental biologists. I'll give you a quote from one of the responders:

"Humans are not a tractable system for doing experimental work in developmental biology, so a good experimental test of the role of the structure is unlikely to have been performed. Thus, I would think that this question is in the range of speculation. It is easy to speculate that something has no function, this takes little imagination, but as you point out the existence on any part of a biological system is a reason from presuming function. I personally favor assuming it has a function until proven otherwise. Your speculation that it serves a transient role, as a signaling center for example, seems like a reasonable hypothesis."

So, there's a reason why I'm not finding much info on it. People don't do experiments with developing fetuses. All your speculation that the embryonic tail serves no function is only that - speculation rooted in an evolutionary framework. Furthermore, as long as the tail is viewed as a mere evolutionary remnant - why would anyone bother testing to see what it does ? Their paradigm has already made the decision for them.

"Similarly, there are interdigital cells that must die during development for our toes and fingers to form correctly.

Oh look! Another evolutionary atavism! I guess that must prove creationism true... ... ... wait..."


And that atavism would be the shadow of our 18 fingered ancestor?? The point is that programmed cell death plays a major part in fetal development. Not every structure that dies off is replaced with something else in its place.

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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 44 of 59 (600535)
01-15-2011 2:26 AM
Reply to: Message 39 by ApostateAbe
01-06-2011 8:50 AM


Re: How Creationism Explains Human Tails (It Doesn't)
I read the abstract - I'm unable to read the whole paper.

The paper talks about the nuts and bolts of WHAT happens. It doesn't seem to get into WHY it happens.

You hypothesize that because it disappears it never has a purpose in the developing embryo.

That doesn't have to be the case. It may serve a temporary purpose - something I offered a few proposals about.


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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 45 of 59 (600537)
01-15-2011 2:59 AM
Reply to: Message 40 by Granny Magda
01-06-2011 11:58 AM


Re: How Creationism Explains Human Tails (It Doesn't)
"Why don't we see eagle-like eyes in humans?"

I have a few thoughts about this - some that came while reading a book about evolution. I think I'll start a new thread about it.

Here it is: http://www.evcforum.net/cgi-bin/dm.cgi?control=msg&m=600542

"If you could show me an example of a trait from one species that also appeared, unaltered, in another, unrelated species, without resorting to known mechanisms such as hybridisation and HGT, I would have to hail it as strong evidence for design in biology."

You yourself mentioned convergent evolution (as have others) - aren't cases of convergent evolution the examples you are looking for?

Silk producing abilities have evolved convergently in spiders, worms, mollusks, and some fish. Did they all get if from the common ancestor?

The presence of the poison tetrodotoxin was evolved convergently in pufferfish, the blue-ringed octopus, and the California newt. Is that the kind of example you're looking for?

"Why a tail? Of all things! It might do whatever developmental job needs to be done, but it sure looks suspicious."

Have you ever examined an early human embryo to see if there are any other early structures that resemble something from some other species? Human embryos go through stages that don't look at all like the finished product. I'm sure you could pick out developing and temporary structures that resemble parts of non-related animals.

"I appreciate the effort you've gone to Aaron, but without some kind of attribution, that quote is worthless.

The quote was from Kerry Kornfeld, Professor of Developmental Biology,Co-Director, Program in Developmental Biology Washington University School of Medicine - if that makes a difference. Feel free to disagree with him. I don't know who the guy is, I just picked him at random.

There's lots of info from others to ponder - but I don't have time now to respond to it all.

Edited by Aaron, : No reason given.


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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 46 of 59 (600541)
01-15-2011 3:29 AM
Reply to: Message 41 by Modulous
01-06-2011 1:38 PM


Re: Common design failure
"So your assertion that there is bound to be similar genetic makeup when creatures 'look similar' is falsified by this evidence."

There's a lot more to DNA than how something looks. Body structure is only a portion of the genetic code.

This is a good point to clarify though - two things can look similar but have very different makeups. Dolphins and sharks "look similar" but their skin and skeletal structure are quite different. I wouldn't argue that their similar appearance necessitates closely related genetics.

Do you know how similar the genetic code is between marsupial and placental moles when it comes to specific items like their similarly structured snout?

My hypothesis would be that similar structures require similar proteins to build them - which requires similar DNA for those parts. Overall genetic differences doesn't negate specific points of genetic similarity. They might be genetically similar when it comes to specific body parts but dissimilar in other areas like metabolism and immune system.

The fact that similar looking but evolutionary distant creatures exist looks to me to be evidence for a designer and against evolution. Evolution predicts that structurally similar creatures share a recent common ancestor.

"Further - we can test genes that have no effect on the way an organism looks such as cytochrome c and the pattern holds as if they were evolved."

You can also create a phylogenetic tree for something like prokaryotes based on one set of genetic properties and then come up with a completely different looking tree using a different set of genetic properties.

Not all genetic markers point in the same direction. (http://pubget.com/search?q=pmid:11798428)

As far as cytochrome c goes, you would expect that bacteria cyt. c would be closer to fish than to horses based on the evolutionary tree - but the opposite is true.

Also, the genetic sequence of hemoglobin in lampreys is more genetically similar to humans than to carp - again, not what ToE would predict.

Edited by Aaron, : No reason given.


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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 51 of 59 (601774)
01-24-2011 12:57 AM
Reply to: Message 49 by cavediver
01-16-2011 2:18 PM


Re: Common design failure
"Again, wrong - and again, can you think why?

Here's a hint - when are these measurements being made?"

The measurements are being made nowadays.

Please explain yourself further.


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Aaron
Member (Idle past 2545 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


Message 53 of 59 (601893)
01-24-2011 9:15 PM
Reply to: Message 48 by Granny Magda
01-16-2011 10:04 AM


Re: How Creationism Explains Human Tails (It Doesn't)
Granny M said:

"The silks employed by different species are different, chemically. If all these species, divided into disparate groups as they are, all had exactly the same silk, it would be impressive. But they don't."

The silks are more similar than you indicate. They may not be identical in nature, but there are specific chemical themes they employ.

"By the way, did you know that spider silks are different from each other? And that they fall into a nested hierarchy? It's an odd design choice to make it look so evolved... "

I don't have a problem with that. I won't make the claim that God created each individual spider species we see today in the exact form that they appear. I'm fine with modern spiders having diversified from an initially created group of spiders.

"They have evolved this feature as a response to exposure to the toxic bacteria in their environment (you''ll note that all of these venomous creatures are aquatic; terrestrial creatures would not be exposed to the bacteria)."

I was not aware of the bacterial symbiosis. It still makes it an interesting question to ponder how each organism independently evolved the ability to resist the poison. One article I read mentions that pufferfish needed mutations in 8 different genes in order for it to happen.

"Okay. Firstly, Kornfeld is the author of a large number of papers about evolution, so he is only going to support your ideas so far. I wonder, did you mention creationism in your email to him? Did you specifically mention that your idea was intended as an alternative to atavism in the embryo and to evolution as a whole?"

Evolution and creationism is a huge issue. I was seeking information about one specific topic.

"The only reason you have to suppose a function for the embryonic tail is to get yourself out of a theological hole and that is just not science."

The fact that humans still have this tail-like structure in itself seems like good evidence that it plays a role. That is science. If evolving organisms are so good at shedding unnecessary parts, why is this one still around?

Here's another email snippet from a different scientist I polled:

Professor David Wilson of the University of Southhampton said:

"The conservation between species of "roles" of genes suggests that a human orthologous gene will have a similar role if there are similarities in the organs/tissues between the species. Thus i could believe that an inducer in an amphibian has similar role in mammals. That wouldnt be considered proof though.

If there were inducers in common, then you would predict that the sequence of each ortholog would be similar and have resisted DNA change due to evolutionary pressure.

A problem with your hypothesis, is how would you test it in humans, given that the manipulation of embryos/genes in rodent or amphibians, cannot be performed in human or primates.
Your hypothesis, or model predicts that the genes important in tail development in non-human species, will be conserved in humans, have resisted DNA change and that if DNA change occured (ie mutation) it would cause a phenotype (disease or malformation in humans). Thus examine children who have malformations of ? legs ? pelvis? spine? hips? (those structures "induced" in amphibians) for DNA change in orthologous genes (for instance brachyury if this is a gene you were thinking about)

not sure if this helps?

I think it is important that you havent accepted the "dogma" or text-book explanation and it is always useful to challenge or question. It doesnt mean you are right, but there are numerous examples when accepted dogma has proved not to be true."

He points out similar issues - this isn't something you can easily do experiments with.

I know I'm getting off topic with this, but creationists aren't the only ones who hand out IOUs for their lack of knowledge. Scientists have theories about the origin of the universe and the origin of first life that they can't substantiate through experiments. Even though scientists can't fully explain these two incredible events they know it must have happened by natural means because "here we are."


This message is a reply to:
 Message 48 by Granny Magda, posted 01-16-2011 10:04 AM Granny Magda has not yet responded

  
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