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Author Topic:   Creationist response to cetacean femur, leg atavism, and limb bud.
Aaron
Member (Idle past 2296 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


(2)
Message 1 of 61 (617641)
05-30-2011 1:53 AM


In another thread, a few others and myself engaged in a discussion about whale evolution and morphology. The issue of vestigial pelvises and limbs arose. I took some time to research these issues further. I’d like to lay out a summary of my findings – a more detailed version will be forthcoming in a paper. In the midst of this I will try and answer some direct questions posed to me by Granny Magda.

These questions include:
1.) How much of a role does sexual dimorphism play in the size and shape of cetacean pelvises?
2.) Why do some whales have femur remnants and/or tibia remnants while others don’t?
3.) How similar is the whale’s pelvis to its ancestors?
4.) Why are some modern whales born with protruding rear “legs”?
5.) What about the molecular and DNA basis for limb loss?

I’ll start with the question: How similar is the whale pelvis to its proposed ancestors?

While the pelvis of land mammals up to Basilosaurus are composed of three distinct bones fused together, the pelvis of modern whales is only composed of one single bone – as noted by several authors who note a single ossification center found in cetacean embryos. This single bone is thought to be the ischium.

Granny Magda brought to my attention the picture of the fin whale pelvis with a few small bone nodules fused to it, labeled the femur. This example was different from the other fin whales in Dr. David Taylor’s pelvis gallery. It is difficult to say for certain if this is the femur or not. The femur of whales is always connected to the pelvis via a ring of cartilage or short tendon strands – not fused directly to it – which is why none of the other fin whale pelvises show an attached femur. The bony nub could also be a bone spur or bone tumor. If the nub represents a femur fused to the pelvis, this would highlight another departure from the typical pelvic structure. In other mammals, the leg bones develop and ossify at different developmental stages than the pelvis does - eliminating the possibility that the femur could fuse to the pelvis.

The other obvious structural departures of the modern whale pelvis include the lack of an acetebular cavitity in which the head of the femur typically resides. Struthers notes the head of the cetacean femur is “in the position which in human surgery we would call dislocation backwards.” The other point of difference is the lack of an obturator foramen in – or the hole in the pelvis through which nerves and muscles pass.

There are other lesser known departures. The pelvic bone in modern whales has rotated about 120 degrees so that the illium end now points to the posterior end instead of to the anterior end, as in typical quadrupeds. In addition, the pelvis is rotated about 90 degrees inward so that the femur bones point towards each other.


This illustration attempts to illustrate how the transition in position must have taken place.

Since the shape of particular bones and the attachment points of specific muscles can differ between families of mammals, the nerve structure of the surrounding muscles are often examined to try and determine homologies between the bones of different animals. However, in the case of whales, the nerves associated with the pelvic musculature are so greatly altered, that it is “utterly impossible yet to homologize them with muscles of terrestrial mammals” according to author Alfred Brazier Howell, a professor of comparative anatomy. I will go into more detail about the musculature differences later.

There is a significant sexual dimorphism in the structure of the male and female pelvis – a fact that Granny Magda tried to downplay saying “individual variation is at least as big a variable.”

While it is true that individual body part variation is probably higher in whales than in other mammals – this is not a reflection of the necessity of those body parts. An example of this is the fluke. Individual variations in fluke shape is one-way researchers can easily tell one specific whale from another.

Even though the pelvic bones can differ between individuals, definite generalizations can still be made. Struthers notes:

“In the female the pelvic bone is shorter, more bent, broader at the angle, and, above all, thinner at and towards the hinder end,”

But the chief difference in the sexes is on the posterior part of the bone, which is so thick and narrow in the male as to be almost rounded in appearance, while in the female it is thin, and may be also broad. The adaptation here is seen by referring to the attachment of the interpelvic ligament to the bone. In the male the thick rounded ligament, supporting the crus penis, is attached to the hinder end of the bone, while in the female the more expanded ligament reaches forwards along the inner margin and upon the bone.”

Differences within a species can also be age related. The pelvis undergoes a dramatic growth spurt around the age of sexual maturity – which varies from 6-20 years old, depending on the species. The pelvis is the last bone to ossify in whales – the same for humans. Therefore, in younger whales, large portions of the pelvis may be completely cartilaginous. These cartilaginous parts would not be preserved in the museum samples recorded in Dr. Taylor’s gallery. gallery

Femur and Tibia in Modern Whales

As noted earlier, an important difference between the pelvic structures of different whale species is the presence of an attached femur in some whales – and even a tibia in others. Is this diversity random? Or is there a pattern to what we see? Most of the marine biologists whom I polled about this diversity hadn’t considered the question before and didn’t have an answer.

Russian zoologist Alexy Yablokov began to classify mysticetes according to the presence of a femur or tibia. He noted the presence of a femur and tibia in right whales and bowhead whales. We can also include sperm whales in this category.

He noted the presence of only a femur in humpbacks, blue whales, and fin whale. We can also add brydes whale, sei, and minke whale to this category. The only other mysticete without a record of a femur remnant is the pygmy right whale – which is the smallest of the baleen whales.

Overall, the femur remnant is far more similar to an epipubic bone than to a typical femur.
Is the Cetacaean Pelvis Vesitigial?

Granny Magda stated:

“I have already told you that it does not matter to me if the pelvis of femur has a function or not. That does not argue against vestigiality in the least. There is nothing about vestigiality that demands lack of all function.”

She rightly states that an organ labeled vestigial isn’t necessarily a useless organ. Yablakov takes up this issue in his discussion of the cetacean pelvis. Historically, vestigiality is defined by a drastic change in form and function from an ancestral state. However, if usefulness isn’t a critical criterion, one wonders how you can discern a vestigial organ from a specialized one – a question that Yablakov poses. If your only criteria is to find examples where an organ exists in an altered state from the ancestral one, then vestigiality becomes a meaningless term. Why not call the front flippers vestigial forelimbs? Or call feathers vestigial scales? If you consider feathers specialized structures adapted to a specific purpose and not vestigial scales, why call the cetacean pelvis vestigial? The most you could say is that it has a specialized function different from the previous function, and if its structure were closer to that of a typical quadruped, it would not be able to perform its adapted function.

After linking the cetacean pelvis to reproductive success, Yablakov makes this claim:

“[the pelvic bones] are important functional structures. These structures not only retained their significance for the organism, but their presence has been proved essential for the normal functioning of life. It follows logically therefore that these organs should not be labeled incipient, embryonic, or "rudimentary" on the one hand, or vestigial on the other.”

Atavistic Hind Limbs

Yablakov questions whether any structure in whales can be considered vestigial if it performs a necessary function. Indeed, he suggests that the term vestigial should only be attached to structures that are not universally shared by all members of a single species. The only example in this category he can give is the occasional presence of hind protrusions in whales. Yablakov observed cases of external cetacean hind limbs during his experiences with the whaling industry.

Edited by Aaron, : Removed large sections to eliminate any potential publishing conflict.


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Message 2 of 61 (617643)
05-30-2011 8:51 AM


Thread Copied from Proposed New Topics Forum

  
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Message 3 of 61 (617644)
05-30-2011 8:57 AM


Moderator Request
If someone would like to perform a good service (perhaps even the OP's author), they could summarize the OP into a few paragraphs summarizing the evidence and arguments.


--Percy
EvC Forum Director

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Aaron
Member (Idle past 2296 days)
Posts: 65
From: Kent, WA
Joined: 12-14-2010


(1)
Message 4 of 61 (617667)
05-30-2011 12:37 PM
Reply to: Message 3 by Admin
05-30-2011 8:57 AM


Re: Moderator Request
If someone would like to perform a good service (perhaps even the OP's author), they could summarize the OP into a few paragraphs summarizing the evidence and arguments.

Good point. I realize this article is a little much for this type of venue. I was mostly using it as an opportunity to flesh out some thoughts.

Basically, I'm tackling three aspects of whale anatomy that have previously been considered only explainable from an evolution standpoint.

1.) The presence of a femur/tibia in certain whales
2.) The occasional presence of a hind "limb" in cetaceans
3.) The emergence and regression of a "limb bud" in cetaceans

I believe each of these has been misrepresented and errantly used as evidence of cetacean quadruped ancestry.

There is good evidence that the limb buds are not limb buds at all, but are involved in forming the mammary region.

This helps explain why the femur and tibia in whales (as well as the pelvis) are so dramatically different in their orientation when compared to a quadruped pelvis and limb. Their developmental process and function are quite different.

Also, if the hind buds are not limb buds, then the occasional hind "limb" can't be a leg reversion - and indeed the physical and chemical evidence strongly suggests these limbs are not at all atavistic reversions.


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Granny Magda
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Posts: 2380
From: UK
Joined: 11-12-2007


Message 5 of 61 (617672)
05-30-2011 1:38 PM
Reply to: Message 1 by Aaron
05-30-2011 1:53 AM


Welcome Back Aaron!
Hi Aaron,

Glad to see you back! I see you have been very busy. you've certainly provided me with plenty of homework. Since there's quite a bit of material here, I will tackle a bit at a time. I may expand this post later, or post again if I have more to say.

Granny Magda brought to my attention the picture of the fin whale pelvis with a few small bone nodules fused to it, labeled the femur. This example was different from the other fin whales in Dr. David Taylor’s pelvis gallery. It is difficult to say for certain if this is the femur or not. The femur of whales is always connected to the pelvis via a ring of cartilage or short tendon strands – not fused directly to it – which is why none of the other fin whale pelvises show an attached femur.

I also showed you this image;

It shows a Right Whale femur, very clearly leg-like and very clearly fused to the pelvis. It certainly looks fused to me. Where are you getting this idea about whale femurs never being fused?

I also note that your previous claim seemed to be that the femur and pelvis were part of a single, non-fused bone. You seem to have moved away from that.

The bony nub could also be a bone spur or bone tumor.

In exactly the same place as one would expect to see a femur. Huh. There's a coincidence. In fact, lots of whales seem to display these "tumours", just in the right spot for a rudimentary femur. Mysterious ways indeed.

The other obvious structural departures of the modern whale pelvis include the lack of an acetebular cavitity in which the head of the femur typically resides.

I don't know about that. This Right Whale pelvis certainly looks like it has an acetabular notch;

Further, here is a diagram from the Bergen Museum site, which clearly shows the acetabular notch;

From here. They also have a shot of the other side of that very same Fin Wale pelvis that we were talking about, which is held at the museum! Small world. Anyway, they seem to recognise an acetabular notch in whales. Perhaps biologists have learned a thing or two since 1881.

I have to wonder where you're getting your data. From an 1881 paper? Really?

Since the shape of particular bones and the attachment points of specific muscles can differ between families of mammals, the nerve structure of the surrounding muscles are often examined to try and determine homologies between the bones of different animals. However, in the case of whales, the nerves associated with the pelvic musculature are so greatly altered, that it is “utterly impossible yet to homologize them with muscles of terrestrial mammals” according to author Alfred Brazier Howell, a professor of comparative anatomy. I will go into more detail about the musculature differences later.

Except that Brazier is wrong. I mean, your own research turned up info on the ischiocavernous muscle, which you talk about in relation to the reproductive anatomy of Right Whales. Aaron, you have an ischiocavernous muscle! So do I! So does every human being and, I dare say all or most tetrapods.

So yes, we can make homologies in the associated musculature around a whale's pelvis.

There is a significant sexual dimorphism in the structure of the male and female pelvis – a fact that Granny Magda tried to downplay saying “individual variation is at least as big a variable.”

I concede that you have done a great job on the reproductive function of the pelvis. However, I still think that what I wrote is true. The high individual variation must still drown out the importance of the sexual variation to at least some extent. However, this in no way argues against an evolutionary origin for whales or in favour creationism.

Russian zoologist Alexy Yablokov began to classify mysticetes according to the presence of a femur or tibia. He noted the presence of a femur and tibia in right whales and bowhead whales. We can also include sperm whales in this category.

It is no coincidence. All but the Sperm Whale are members of the same family, Balaenidae. Of those all the Right Whales are of the same genus. It is only to be expected that they would share homologies. This is clear evidence of their evolutionary relatedness. You are drawing cladograms.

He noted the presence of only a femur in humpbacks, blue whales, and fin whale. We can also add brydes whale, sei, and minke whale to this category.

Again, these are all closely related. All are of the same family, only the Humpback is outside of the Balaenoptera genus. You are only highlighting their relatedness.

Consequently, bowhead whales have one of the largest penis sizes of any whale – up to 9 feet long, or around 14% of total body length.

Sir Bowhead Whale, we salute you!

As I have said, all this stuff about reproductive anatomy and a function ofr the whale's pelvis is good work. i agree that the pelvis of the Bowhead plays a role in its reproductive success.

I am less clear what function the femur or tibia might play. Or why this role must necessarily involve a bone that strongly resembles a pelvis. If the bone is novel and not related to a pelvis, why is it so similar? Once again, i can only conclude that God really wants us to believe in evolution.

The next aspect of pelvic functionality I will discuss is locomotion. This is an aspect that is hardly ever mentioned in the literature. One expert on cetacean locomotion that I polled knew of no paper discussing a link between pelvic structure and locomotion. I later found just such a paper.

Dr. Yuko Tajima examined the musculature connections associated with the cetacean pelvis and suggested their role in locomotion. paper

I couldn't find that paper. Could you provide a link?

I did find this, by the same author;

quote:
Comparative anatomical study on the structure around the pelvis in the finless porpoises (Neophocaena phocaenoides)

Abstract;The morphology of modern cetaceans results from adaptation of ancestral terrestrial mammals to aquatic life through evolutionary processes. Consideration of the causes and processes of the loss of hind limbs and the reduction of the pelvis are interesting and important. Some primitive fossil cetaceans are known to have both fore- and hind- limbs. In modern cetaceans vestigial pelvic bones are, in general, a pair of slender rod-like structures within the abdominal wall muscles just anterior to the anus. The pelvic bones do not have bony articulations with the axial vertebrae and have no appendicular skeleton, except in some great whales, which occasionally have rudimentary femora (Burne, 1952; Nemoto, 1963; Ogawa and Kamiya, 1957; Slijper, 1958). In the present study, the pelvic bones of the finless porpoise were confirmed to follow the basic form and configuration of cetaceans. Muscles such as M ishciocaudalis, M ischiocavernosus and M bulbospongiosus have attachments on the pelvic bones in both sexes. Moreover, we confirmed that the caudal end of M. rectus abdominis (RA) constitutes a strong dorso-caudad aponeurosis (Fig.1, B), after sending a small muscular slip to the pelvis (Fig.1, A) and inserting at the superficial fascia of M. ischiocaudalis (Fig.1, C). In the most caudal portion of M. transversus abdominis (TA), the strong inner fascia of TA originated at the Proc. transverses and suspended the pelvis as part of the abdominal wall (Fig.2). It should be emphasized that insertion B is much the same as that of the terrestrial mammals. As mentioned above, some soft tissues around the pelvis are transformed following the drastic transformation of the pelvis. This transformation tells us that cetaceans adapted to aquatic life during evolutionary processes, choosing the tail flukes operated by the powerful trunk muscles for locomotion instead of modifying the hind limbs into hind flippers as seen in pinnipeds....


Source

Once again, the evidence for creation/against evolution that you cite seems to have slipped by its authors without their ever noticing it.

Overall though, I don't see how a function for the pelvis argues against its vestigiality. Vestigiality does not preclude function. I have made that clear several times. You say;

However, if usefulness isn’t a critical criterion, one wonders how you can discern a vestigial organ from a specialized one – a question that Yablakov poses. If your only criteria is to find examples where an organ exists in an altered state from the ancestral one, then vestigiality becomes a meaningless term.

but that is merely a gripe about the term "vestigial", not an argument against an evolutionary origin for the whale.

Okay, I'm going to take a break for now, but I do have more to say. I will post again later.

Mutate and Survive


On two occasions I have been asked, – "Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?" ... I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question. - Charles Babbage

This message is a reply to:
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Replies to this message:
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slevesque
Member (Idle past 2977 days)
Posts: 1456
Joined: 05-14-2009


Message 6 of 61 (617689)
05-30-2011 3:11 PM
Reply to: Message 1 by Aaron
05-30-2011 1:53 AM


First of all, this was a very well presented opening post Aaron,even though it showed me that anatomy wasn't my forte.

And for this reason, I will let you and GM grind out the discussion about the specific issue of whales vestigial part, but this has become a very good example of what I am saying about the paradigm-based approach of evidence. Clearly, the femur's and buds of whales will only be seen as evidence of evolution only for a person who already believes in evolution.

The one part I thought was very interesting in your OP, and that I feel comfortable in discussing, is this section about vestigial organs:

She rightly states that an organ labeled vestigial isn’t necessarily a useless organ. Yablakov takes up this issue in his discussion of the cetacean pelvis. Historically, vestigiality is defined by a drastic change in form and function from an ancestral state. However, if usefulness isn’t a critical criterion, one wonders how you can discern a vestigial organ from a specialized one – a question that Yablakov poses. If your only criteria is to find examples where an organ exists in an altered state from the ancestral one, then vestigiality becomes a meaningless term. Why not call the front flippers vestigial forelimbs? Or call feathers vestigial scales? If you consider feathers specialized structures adapted to a specific purpose and not vestigial scales, why call the cetacean pelvis vestigial? The most you could say is that it has a specialized function different from the previous function, and if its structure were closer to that of a typical quadruped, it would not be able to perform its adapted function.

This is in fact a rather good formulation of what had been going in the back of my head for a while now: I can understand that a vestigial organ should not be obliged to have no function, but it seems to me that within an evolution perspective, there should be some vestigial features that have no purpose or function at all, I would even go as far as suggest that this should be a majority. We should expect some features to have had a single function, lost it's usefulness with evolution, and hasn't had the time to evolve other functions.

Yet if the vast majority (if not all) of claimed vestigial features have functions, and usually pretty specialised function, it begs the question as to why we should consider them any more or less vestigial then feathers being vestigial scales, etc. and it brings into question if the issue of vestigiality has any relevance at all.

(Might I suggest that we make this a great debate thread with Aaron, GM, myself and another evolutionist ? perhaps Percy ?)

Edited by slevesque, : No reason given.


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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006
Member Rating: 8.3


Message 7 of 61 (617690)
05-30-2011 3:13 PM
Reply to: Message 1 by Aaron
05-30-2011 1:53 AM


Wecome Back From Me Too
I'd like to join GM in welcoming you back, it's a pleasure to have a creationist with such a high standard of debate. (We're still going to metagrobolize you, but that's the price you pay for being a creationist.)

I shall wait for GM's promised second post before I see if I have anything to add, because otherwise we are likely to waste time covering the same ground.

P.S: Thanks for the hot whale porn.


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NoNukes
Inactive Member


Message 8 of 61 (617698)
05-30-2011 4:03 PM
Reply to: Message 6 by slevesque
05-30-2011 3:11 PM


slevesque writes:

Clearly, the femur's and buds of whales will only be seen as evidence of evolution only for a person who already believes in evolution.

That's not clear to me. Aaron has specific reasons why he thinks the buds are not evidence of evolution. It may well be that additional evidence and/or discussion confirms or refutes his reasoning.


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slevesque
Member (Idle past 2977 days)
Posts: 1456
Joined: 05-14-2009


Message 9 of 61 (617701)
05-30-2011 5:02 PM
Reply to: Message 8 by NoNukes
05-30-2011 4:03 PM


That's not clear to me. Aaron has specific reasons why he thinks the buds are not evidence of evolution. It may well be that additional evidence and/or discussion confirms or refutes his reasoning.

I say it is clear because a creationist will see the specificity in the design of form and function, while the evolutionists will see that the bones have analog counterparts in terrestial mammals that will hint at common descent.

As I said, the vestigial argument would be much more effective if the vestigial features had no function. This is clearly not the case for the vast majority of claimed vestigial features, and in fact I think we should expect much more functionless vestigial features then we see., because a vestigial feature with a function should only arise if the orignal feature had either more then one original feature, or if it evolved a second function afterwards, both possibilities which shouldn't be an overwhemling majority, yet it seems it is.

Edited by slevesque, : No reason given.


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Dr Adequate
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Posts: 16107
Joined: 07-20-2006
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Message 10 of 61 (617705)
05-30-2011 5:55 PM
Reply to: Message 6 by slevesque
05-30-2011 3:11 PM


I can understand that a vestigial organ should not be obliged to have no function, but it seems to me that within an evolution perspective, there should be some vestigial features that have no purpose or function at all, I would even go as far as suggest that this should be a majority. We should expect some features to have had a single function, lost it's usefulness with evolution, and hasn't had the time to evolve other functions.

But since the production of any part has a biological cost, we should expect parts without any function to be eliminated by natural selection by and by. Which suggests that they should be a minority.


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Granny Magda
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Posts: 2380
From: UK
Joined: 11-12-2007


Message 11 of 61 (617706)
05-30-2011 5:58 PM
Reply to: Message 7 by Dr Adequate
05-30-2011 3:13 PM


Re: Wecome Back From Me Too
Hi Dr A,

I shall wait for GM's promised second post before I see if I have anything to add, because otherwise we are likely to waste time covering the same ground.

Await away, but don't expect anything before tomorrow evening. I was planning to comment on Aaron's claims about limb development and about his ideas about supernumerary limbs.

Now though, I'm off to bed, I've work in the morning. Those cats won't shave themselves.

Mutate and Survive


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Dr Adequate
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(1)
Message 12 of 61 (617708)
05-30-2011 6:15 PM
Reply to: Message 9 by slevesque
05-30-2011 5:02 PM


I say it is clear because a creationist will see the specificity in the design of form and function, while the evolutionists will see that the bones have analog counterparts in terrestial mammals that will hint at common descent.

But the specificity is not seen nearly so clearly as the homology. One does not look at GM's pictures of whale pelvises and think: "By golly, that looks like exactly what an all-wise God would have thought of to attach a right whale's penis to!"

Or consider the wing of an ostrich, where the homology is even clearer. Ostriches, you will perhaps say, use their wings for running. But it is hard to see that the form of the wings, so closely resembling that of flying birds, was specifically designed for this task. Meanwhile God bestowed ordinary arms on other flightless bipeds such as hadrosaurs, because that was best for them ...

Eyeless crabs use their eyestalks for ... actually, I don't know what, except that if you just removed them the crabs would have holes in their heads which might provide ingress to disease and parasites. But whatever they use them for (if anything) it is easier to see that they are homologous to eyestalks than it is to see that they are the ideal design to do something else completely and just by chance this function is best served by things which look just like eyestalks.

What we see again and again is that a supposedly omniscient God designed some organism and it just so happened that every single time the best solution he could think of was one completely in line with evolutionary biology. Now the optimality of these solutions is not seen so much as hoped for; and the magnitude of the coincidence goes entirely unexplained.


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NoNukes
Inactive Member


Message 13 of 61 (617709)
05-30-2011 6:48 PM
Reply to: Message 9 by slevesque
05-30-2011 5:02 PM


slevesque writes:


I say it is clear because a creationist will see the specificity in the design of form and function, while the evolutionists will see that the bones have analog counterparts in terrestial mammals that will hint at common descent.

Perhaps that would be your line of reasoning. Aaron seems to argue that there are flaws in the evolution based reasoning that evolutionists should appreciate. Maybe he's right.

This is clearly not the case for the vast majority of claimed vestigial features

Evidence please.

You seem to say clearly quite often.


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jar
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Posts: 31760
From: Texas!!
Joined: 04-20-2004
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Message 14 of 61 (617710)
05-30-2011 7:05 PM
Reply to: Message 9 by slevesque
05-30-2011 5:02 PM


slevesque writes:

That's not clear to me. Aaron has specific reasons why he thinks the buds are not evidence of evolution. It may well be that additional evidence and/or discussion confirms or refutes his reasoning.

I say it is clear because a creationist will see the specificity in the design of form and function, while the evolutionists will see that the bones have analog counterparts in terrestial mammals that will hint at common descent.

Which is a pretty worthless assertion unless you also present the mechanism and model that allows the so called designer to interfere or influence "the design of form and function".

Does the designer use tiny little tweezers or just magic? Does the designer hold its tongue in a certain way or stand on one foot?


Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 9 by slevesque, posted 05-30-2011 5:02 PM slevesque has not yet responded

Replies to this message:
 Message 15 by Bolder-dash, posted 05-30-2011 11:48 PM jar has acknowledged this reply
 Message 16 by Adminnemooseus, posted 05-31-2011 12:18 AM jar has not yet responded
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Bolder-dash
Member (Idle past 1967 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 15 of 61 (617725)
05-30-2011 11:48 PM
Reply to: Message 14 by jar
05-30-2011 7:05 PM


I am curious why you are allowed to continually pull out this same line of diversion without anyone calling you on it. You can't counter every criticism of your theory with "Well, if my theory is wrong, why don't you prove your theory."

That's not a defense of your theory at all. No one is obliged to describe how a designer might work, in order to show the incorrectness of your claims. If slevesque notes that in your evolutionary model, functions must often come and go, so we should see many useless vestigial organs (and yet we don't), that comment stands on its own ground. He is not further obligated to provide the details of a whole alternative-just because your version is poor.

I suppose he could give an alternative that makes as little sense as the one evolutionists are providing, but then what would be the point? The point is that your theory says it should look one way, and yet it doesn't. Dr. A is trying to make the argument that natural selection would eventually filter out these useless vestigials, but that of course is just a convenient excuse, not a logical one. Are we always at the end of natural selection doing something, why are we never in the middle of it? Why can't we see the vestigial BEFORE nature has weeded them out. As sleve inferred, with so many adaptive features always coming and going in order for their to be diversity of life, there should be thousands, millions of features left stranded.

Yet all you really have is an appendix.

Wait, scratch that, we found out an appendix is useful. Dam.

A tail? Can someone please find me a useless tail!


This message is a reply to:
 Message 14 by jar, posted 05-30-2011 7:05 PM jar has acknowledged this reply

Replies to this message:
 Message 20 by Dr Adequate, posted 05-31-2011 2:37 AM Bolder-dash has not yet responded

  
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