The myth of the "Nested Hierarchy of Common Descent"

[[serious]]

So originally you said:
"The underlying genetics will differ with analogous structures, but be shared with homologous structures."

Are you amending this statement to include the possibility that the developmental pathways of homologous structures can be controlled by entirely different genes? (Also that the development of analogous structures can be controlled by homologous genes.) This seems to be a significant departure from your original claim.

More importantly, I would like to know why you appear to accept that certain genes involved in the development of homologous morphology can be changed, yet other genes involved in development can not be changed, (if that is what you're implying) If the gene doing the signaling can be swapped at some stage of "evolution", why exactly can't other genes encoding for specific morphological organization?

A homologous structure will show homologies in the genes used to create it. Now, new genes can also affect the homologous structure's formation, but that doesn't nullify the homologies in the other genes. Likewise, one gene may cease to impact the structure's formation, and that would not nullify the remaining homologies.

I did think of at least a hypothetical situation in which that could be considered incorrect though. Say we have some structure controlled by a single gene. For example, some surface protein for a bacteria, maybe a binding site. Another gene then also gets involved. Now you have two genes controlling that surface structure. As it evolves, perhaps the second gene takes over more of the function, and eventually the first gene stops actually having anything to do with that protein. Now you have a binding site, that has existed as a binding site, but is now created by an entirely different gene. Are the genes homologous? Nope. Are those two structures homologous? Harder to answer, but I'd lean towards yes.

However, I'm unaware of anything like that which actually exists.

 

[lifepsyop]

A homologous structure will show homologies in the genes used to create it. Now, new genes can also affect the homologous structure's formation, but that doesn't nullify the homologies in the other genes. Likewise, one gene may cease to impact the structure's formation, and that would not nullify the remaining homologies.

So a homologous structure is one where the underlying genes are homologous except for the ones that aren't.

I did think of at least a hypothetical situation in which that could be considered incorrect though. Say we have some structure controlled by a single gene. For example, some surface protein for a bacteria, maybe a binding site. Another gene then also gets involved. Now you have two genes controlling that surface structure. As it evolves, perhaps the second gene takes over more of the function, and eventually the first gene stops actually having anything to do with that protein. Now you have a binding site, that has existed as a binding site, but is now created by an entirely different gene. Are the genes homologous? Nope. Are those two structures homologous? Harder to answer, but I'd lean towards yes.

However, I'm unaware of anything like that which actually exists.

How would one identify such a structure as a structural homology in the first place, since such inference would be derived by the underlying gene. One would interpret the homology as an analogy.

 

[[serious]]

So a homologous structure is one where the underlying genes are homologous except for the ones that aren't.

Not sure what you are trying to say here.

Let me restate and see if that clears up my position:
Being homologous doesn't forever lock in a list of genes and only those genes.

How would one identify such a structure as a structural homology in the first place, since such inference would be derived by the underlying gene. One would interpret the homology as an analogy.

Recognizing such an item would indeed be difficult. I don't have any good solution for identification of such a structure, but thought it was an interesting thought exercise. We can ignore it if you feel it's muddying the waters to much.

 

[Loudmouth]

So a homologous structure is one where the underlying genes are homologous except for the ones that aren't.

Homologous structures were found before we even knew of genetics. The fact that you have to run away from the obvious says a lot about your argument.

 

[lifepsyop]

Homologous structures were found before we even knew of genetics. The fact that you have to run away from the obvious says a lot about your argument.

Really, and how were these "homologous structures" (i.e. structures with shared ancestry) positively identified?

I'll remind you that you were completely incapable of answering this question last time I asked. Of course you will dance around it this time as well.

 

[Loudmouth]

Really, and how were these "homologous structures" (i.e. structures with shared ancestry) positively identified?

It wasn't that hard.

I bet a 3 year old could do it.

 

[lifepsyop]

It wasn't that hard.

I bet a 3 year old could do it.

So your answer is that you look at pictures and make assumptions. Clearly very rigorous scientific criteria.

 

[Loudmouth]

So your answer is that you look at pictures and make assumptions. Clearly very rigorous scientific criteria.

Are you saying that you can not find the homologous structures in that picture?

Wow, you must have flunked biology in the 1st grade.

 

[lifepsyop]

Pop-Quiz Loudmouth

Are the digits on the limbs of these two skink genera homologous?

 

[Loudmouth]

Pop-Quiz Loudmouth

Are the digits on the limbs of these two skink genera homologous?

Phalanges on all tetrapods are homologous.

 

[lifepsyop]

Phalanges on all tetrapods are homologous.

Evidence for repeated acquisition and loss of complex body-form characters in an insular clade of Southeast Asian semi-fossorial skinks.

...Our phylogenetic results support independent instances of complete limb loss as well as multiple instances of digit and external ear opening loss and re-acquisition. Even more striking, we find strong statistical support for the re-acquisition of a pentadactyl body form from a digit-reduced ancestor.

.... this strange, shared phalangeal formula among all pentadactyl members of the genus may be evidence that digits have been reacquired via a novel evolutionary pathway, unique among pentadactyl lizards.

http://www.ncbi.nlm.nih.gov/pubmed/21884062

Oops, your rigorously scientific game of Pictionary may have failed you.

 

[Loudmouth]

Evidence for repeated acquisition and loss of complex body-form characters in an insular clade of Southeast Asian semi-fossorial skinks.

...Our phylogenetic results support independent instances of complete limb loss as well as multiple instances of digit and external ear opening loss and re-acquisition. Even more striking, we find strong statistical support for the re-acquisition of a pentadactyl body form from a digit-reduced ancestor.

.... this strange, shared phalangeal formula among all pentadactyl members of the genus may be evidence that digits have been reacquired via a novel evolutionary pathway, unique among pentadactyl lizards.

http://www.ncbi.nlm.nih.gov/pubmed/21884062

Oops, your rigorously scientific game of Pictionary may have failed you.

It may be? Perhaps you could present some conclusive evidence? What were the evolutionary pathways for the re-acquisition? Did it use completely different progenitor cells and gene pathways?

 

[lifepsyop]

It may be? Perhaps you could present some conclusive evidence? What were the evolutionary pathways for the re-acquisition? Did it use completely different progenitor cells and gene pathways?

Ah, the Loudmouth shuffle. Sorry, but the evolutionists themselves propose novel evolutionary pathways for the independent origin of tetrapod digits. The same digits you just matter-of-factly asserted were homologous. Once again you are shown to have no idea what you're talking about and that you're just flinging around bald assertions.

 

[Loudmouth]

Ah, the Loudmouth shuffle. Sorry, but the evolutionists themselves propose novel evolutionary pathways for the independent origin of tetrapod digits. The same digits you just matter-of-factly asserted were homologous. Once again you are shown to have no idea what you're talking about and that you're just flinging around bald assertions.

So you can't show that they are analogous? Just what I thought.

 

[lifepsyop]

So you can't show that they are analogous? Just what I thought.

Evolutionists believe they are most likely analogous.
And you can't show that they're homologous.
Do you see what a trainwreck your position is? It's sad to watch you have to keep dancing around like this.

 

[Loudmouth]

Evolutionists believe they are most likely analogous.
And you can't show that they're homologous.

Where is the evidence?

Re-acquisition can occur through the same evolved pathways. We see this with atavisms all of the time.

 

[Strathos]

It seems to me that, in order for the OP to substantiate his claim, he would have to give an example of a hypothetical piece of evidence proposed by scientists as a falsification of common descent, which was later discovered to actually exist, and then explained with one of the types of excuses suggested. In other words, show an example of scientists claiming something would falsify common descent, then finding that and retracting their claim about it being a falsification.

 

[crjmurray]

It seems to me that, in order for the OP to substantiate his claim, he would have to give an example of a hypothetical piece of evidence proposed by scientists as a falsification of common descent, which was later discovered to actually exist, and then explained with one of the types of excuses suggested. In other words, show an example of scientists claiming something would falsify common descent, then finding that and retracting their claim about it being a falsification.

Seconded.

 

[lifepsyop]

Where is the evidence?

For homology? You have none. Like I've been saying.

Re-acquisition can occur through the same evolved pathways. We see this with atavisms all of the time.

Evolutionists using the very same phylogenetic methodology you hold as gospel proof of common descent, are now suggesting that tetrapod digits have evolved again independently through novel evolutionary pathways. This is the exact opposite of homology that you previously asserted. This is the evolutionists' "peer-reviewed" argument, not mine. Deal with it. Or keep dancing and show everyone how much denial you're in.

 

[lifepsyop]

It seems to me that, in order for the OP to substantiate his claim, he would have to give an example of a hypothetical piece of evidence proposed by scientists as a falsification of common descent, which was later discovered to actually exist, and then explained with one of the types of excuses suggested. In other words, show an example of scientists claiming something would falsify common descent, then finding that and retracting their claim about it being a falsification.

We just saw one of CF's star evolutionists claim all tetrapod phalanges are homologous. This has been a widespread evolutionary claim in general, and they've beaten the public over the heads with it for decades.

(from the Department of Biology at Miami U)
"Structures derived from a common ancestral structure (that may or may not be used for the same function in the species in which it occurs) are called homologous structures.

A classic example of homology is seen in the skeletal components of vertebrates..."

http://www.bio.miami.edu/dana/160/160S13_5.html


Yet more recently, evolutionists themselves are now proposing that major elements of the vertebrate limb arose independently in separate lineages, that is, the phalanges "evolved" independently in a group of lizards, which I just linked to on this page.

If that isn't a failed prediction, I don't know what is. But that's exactly the point. When evolutionary predictions fail, even the failures can be accommodated into the theory. This is because Evolution is not a real scientific theory, but an amorphous blob that absorbs whatever data it rolls over.