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Theory Of Evolution And Common Ancestry - Religion (2) - Nairaland

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Re: Theory Of Evolution And Common Ancestry by Nobody: 6:09pm On Dec 01, 2014
davien:
We could atleast know if its just a molecular vestige with that..

Irrespective of that,the slug has a subcellular endosymbiotic relationship with the alga Codium fragile....
so how do you expect not to find plant genes on the slug when it has a subcellular symbiotic relationship with a plant?

Humans also have genes from different viruses....does that make a human a virus?

You are a virus.... all humans are! We are all conceived and born in sin! Your ability to sin makes you a virus grin All humans are viruses grin Until you pass the test, you are nothing but a destructive virus grin Humans are by far more destructive than any virus known to man grin

A scientific topic on a religion board needs both spiritual and carnal interpretations, don't you think? grin
Re: Theory Of Evolution And Common Ancestry by plaetton: 6:17pm On Dec 01, 2014
Weah96:


You have a certain aggression about you. What's the point of opening a thread if you're going to behave like a spoiled child who has just conceded a goal?

What's the point of mentioning the slug in the OP, if I'm expected to completely ignore it?



This slug displays a sociopathic behavior wherein anger and aggression are triggered when terms and statements are not framed in his custom language.

But it's also a convenient and artful way to deflect issues and avoiding committing himself to any point.

He is an artful dodger.
Re: Theory Of Evolution And Common Ancestry by Weah96: 6:20pm On Dec 01, 2014
sinequanon:


Answer the question. Don't try to twist it into an assertion. That is troll behaviour.

How do you justify HEREDITY AS A DEFAULT ASSUMPTION without independent proof, when other mechanisms exist?



Stop twisting and using rhetoric. If you have a point, you can phrase it directly..

e.g DNA testing is perfect, therefore heredity can be relied on to confirm immediate parentage in a custody case, therefore fossils with similar morphology have a common ancestor.

When you word it directly, instead of using some half-baked rhetoric, we can see where you are going, and that it is rubbish.

Heredity is not assumed by default. Where did you get that idea from?
Re: Theory Of Evolution And Common Ancestry by sinequanon: 6:35pm On Dec 01, 2014
Weah96:


Heredity is not assumed by default. Where did you get that idea from?

At last!

Umpteen posts later, somebody addresses the OP. Was that so difficult?

OK, taxonomists assert that birds are [size=16pt]descended[/size] from early reptiles, based on morphology. Which [size=16pt]non-inheritance[/size] mechanisms were considered to explain morphological similarities? Or was only heredity considered?

So, I am looking for refutations such as

The taxonomy is not based on morphology, it is based on ______________.

or

Mechanisms X, Y , Z were considered in case (give examples), but heredity was preferred because ____________________
Re: Theory Of Evolution And Common Ancestry by Weah96: 7:58am On Dec 02, 2014
sinequanon:


At last!

Umpteen posts later, somebody addresses the OP. Was that so difficult?

OK, taxonomists assert that birds are [size=16pt]descended[/size] from early reptiles, based on morphology. Which [size=16pt]non-inheritance[/size] mechanisms were considered to explain morphological similarities? Or was only heredity considered?

So, I am looking for refutations such as

The taxonomy is not based on morphology, it is based on ______________.

or

Mechanisms X, Y , Z were considered in case (give examples), but heredity was preferred because ____________________

Other methods of gene transfer were first ruled out. Horizontal gene transfer has been shown to occur between prokaryotes, prokaryotes to humans, prokaryotes to eukaryotic microbes but not between two full sized eukaryotes like dinosaurs and birds.

Mimicry doesn't involve gene transfer at all.

Do you know of any other method by which genes can be transferred without reproduction?
Re: Theory Of Evolution And Common Ancestry by sinequanon: 11:12am On Dec 02, 2014
Weah96:


Other methods of gene transfer were first ruled out. Horizontal gene transfer has been shown to occur between prokaryotes, prokaryotes to humans, prokaryotes to eukaryotic microbes but not between two full sized eukaryotes like dinosaurs and birds.

Mimicry doesn't involve gene transfer at all.

Do you know of any other method by which genes can be transferred without reproduction?

You still are confused and going round in circles. So let us take smaller steps.

1. Apart from morphological evidence, do you know of any other major method considered in asserting that birds descended from early reptiles?

2. IF ONLY MORPHOLOGICAL EVIDENCE WAS CONSIDERED, why was DESCENDANCY ASSUMED to be the cause of morphological similarity, when other factors can cause morphological similarity?

If you are trying to say that gene transfer was not considered, explain why, and then explain why other factors that cause morphological similarity were not considered.

If you are trying to say that a particular method of gene transfer was considered, but the others weren't, then tell us which and explain why.

IF YOU ACCEPT THAT THE ONLY METHOD OF TAXONOMICAL CATEGORIZATION OF BIRDS IS MORPHOLOGY, THEN, AS THE OP EXPLAINS, THIS DOES NOT PROVE DESCENDANCY.

(awaiting your next evasion tactic...)

1 Like

Re: Theory Of Evolution And Common Ancestry by Kay17: 11:33am On Dec 02, 2014
sinequanon:
Taxonomy started out as an exercise in categorizing organism by similarity in form -- morphology.

Heredity was determined as the mechanism which explained why similar structures could be found in different species.

This led Darwin to propose common ancestry and a possible ultimate common ancestor -- "last universal ancestor".

This is really a problem in information transfer. How does information (like structure) transfer from one organism to another. Just because we see this information transfer, does it demonstrate heredity?

Take a look at these..



http://www.pbase.com/image/103530756

This is not a wasp. Its structural similarities to a wasp are not inherited. It is a moth.



http://en.wikipedia.org/wiki/Elysia_viridis

This slug contains "genes" found in plant cell nucleii. This transfer of information is not by inheritance.

Therefore evidence for transfer of information, morphological or genetic, does not imply heredity.

This puts into question the taxonomical basis for common ancestry.

[Please ignore the trolls.

They will obfuscate by ignoring the point, repeating how "science works", regurgitating the Theory of Evolution for no reason, and copying and pasting irrelevant essays on the NON-inheritance mechanisms (like mimicry in natural selection) that may account for the examples above (just to give the impression that they are clued up and nobody else is). Meanwhile, their essay will not address the point of the thread. Please ignore them -- the usual suspects.]

But Life is often pictured as a tree with numerous branches and connections, hence there is the possibility for a remote relationship between two forms of life across the extremes of a spectrum. From your OP, I think you are trying to thread a direct relationship between the specimens.
Re: Theory Of Evolution And Common Ancestry by sinequanon: 11:56am On Dec 02, 2014
Kay17:


But Life is often pictured as a tree with numerous branches and connections, hence there is the possibility for a remote relationship between two forms of life across the extremes of a spectrum. From your OP, I think you are trying to thread a direct relationship between the specimens.

The similarity between the moth and a wasp is generally explained as mimicry. The predominant theory is that moths of the species survived by looking wasp-like, thereby avoiding predation. Good mimicry is postulated as the environmental selective pressure, in this case.

For the slug, the theory is that chloroplasts were able to survive inside it. The slug evolved, by a method involving horizontal gene transfer, to be able to metabolize the products of the chloroplast photosynthesis.

I thought all this was clear, and it is not the question.

The question is why IN GENERAL morphological similarities, which could potentially be due to either of the above (or other mechanism), are mostly ASSUMED to be due to HEREDITY without considering the other possibilities.
Re: Theory Of Evolution And Common Ancestry by sinequanon: 12:24pm On Dec 02, 2014
For example..

http://en.wikipedia.org/wiki/Horizontal_gene_transfer

[size=18pt]Most thinking[/size] in genetics has [size=18pt]focused[/size] upon vertical transfer, but there is a [size=18pt]growing awareness[/size] that horizontal gene transfer is a highly significant phenomenon and among single-celled organisms perhaps the dominant form of genetic transfer.[11][12]

Common ancestry had already been [size=18pt]decided[/size] before this "growing awareness" of considerations other than genetic inheritance.

It makes sense that common ancestry, and particularly "last universal ancestor", needs to be completely reviewed.
Re: Theory Of Evolution And Common Ancestry by Kay17: 3:03pm On Dec 02, 2014
sinequanon:


The similarity between the moth and a wasp is generally explained as mimicry. The predominant theory is that moths of the species survived by looking wasp-like, thereby avoiding predation. Good mimicry is postulated as the environmental selective pressure, in this case.

For the slug, the theory is that chloroplasts were able to survive inside it. The slug evolved, by a method involving horizontal gene transfer, to be able to metabolize the products of the chloroplast photosynthesis.

I thought all this was clear, and it is not the question.

The question is why IN GENERAL morphological similarities, which could potentially be due to either of the above (or other mechanism), are mostly ASSUMED to be due to HEREDITY without considering the other possibilities.

Cos that's the fundamental assumption for common ancestry. Everybody in the world knows that.
Re: Theory Of Evolution And Common Ancestry by sinequanon: 3:21pm On Dec 02, 2014
sinequanon:
The question is why IN GENERAL morphological similarities, which could potentially be due to either of the above (or other mechanism), are mostly ASSUMED to be due to HEREDITY without considering the other possibilities.
Kay17:


Cos that's the fundamental assumption for common ancestry. Everybody in the world knows that.

It is assumed because it is assumed.

Good answer.

Anyone else?
Re: Theory Of Evolution And Common Ancestry by Weah96: 3:42pm On Dec 02, 2014
sinequanon:


You still are confused and going round in circles. So let us take smaller steps.

1. Apart from morphological evidence, do you know of any other major method considered in asserting that birds descended from early reptiles?

2. IF ONLY MORPHOLOGICAL EVIDENCE WAS CONSIDERED, why was DESCENDANCY ASSUMED to be the cause of morphological similarity, when other factors can cause morphological similarity?

If you are trying to say that gene transfer was not considered, explain why, and then explain why other factors that cause morphological similarity were not considered.

If you are trying to say that a particular method of gene transfer was considered, but the others weren't, then tell us which and explain why.

IF YOU ACCEPT THAT THE ONLY METHOD OF TAXONOMICAL CATEGORIZATION OF BIRDS IS MORPHOLOGY, THEN, AS THE OP EXPLAINS, THIS DOES NOT PROVE DESCENDANCY.

(awaiting your next evasion tactic...)

I think you need a proper understanding of how traits are determined to be homologous, like the unique bones found only in birds and dinosaurs fossils.

http://ncse.com/creationism/analysis/circular-definitions

"This claim has a long history in the creationist literature, but is uniformly rejected by biologists as rooted in basic misunderstandings. The apparent homology of a single trait would not be treated as evidence of common descent. By examining multiple traits, all showing the same nested hierarchy of modifications of a common starting point, scientists can test hypotheses about common descent. There is nothing circular about this process."


Consequently, here is your answer. Feel free to replace the name Wells with yours, wherever it is found.

[b]"Wells claims that homology is used in a circular fashion by biologists because textbooks define homology as similarity inherited from a common ancestor, and then state that homology is evidence for common ancestry. Wells is correct: this simplified reading of homology is indeed circular. But Wells oversimplifies a complex system into absurdity instead of trying to explain it properly. Wells, like a few biologists and many textbooks, makes the classic error of confusing the definition of homology with the diagnosis of a homologous structure, the biological basis of homology with a procedure for discovering homology. In his discussion, he confuses not only the nature of the concept but also its history; the result is a discussion that would confuse. What is truly important here is not whether textbooks describe homology circularly, but whether homology is used circularly in biology. When homology is properly understood and applied, it is not circular at all.

Today, biologists still diagnose homologous structures by first searching for structures of similar form and position, just as pre-Darwinian biologists did. (They also search for genetic, histological, developmental, and behavioral similarities.) However, in our post-Darwin period, biologists define a homologous structure as an anatomical, developmental, behavioral, or genetic feature shared between two different organisms because they inherited it from a common ancestor. Because not all features that are similar in two organisms are necessarily inherited from a common ancestor, and not all features inherited from a common ancestor are similar, it is necessary to test structures before they can be declared homologous. To answer the question, "could this feature in these groups be inherited from a common ancestor?" scientists compare the feature across many groups, looking for patterns of form, function, development, biochemistry, and presence and absence.

If, considering all the available evidence, the distribution of characteristics across many different groups resembles a genealogical pattern, it is very likely that the feature reflects common ancestry. Future tests based on more features and more groups could change those assessments, however — which is normal in the building of scientific understanding. Nevertheless, when a very large amount of information from several different areas (anatomy, biochemistry, genetics, etc.) indicates that a set of organisms is genealogically related, then scientists feel confident in declaring the features that they share are homologous. Finally, while judgments of homology are in principle revisable, there are many cases in which there is no realistic expectation that they will be overturned.

So Wells is wrong when he says that homology assumes common ancestry. Whether a feature reflects common ancestry of two or more animal groups is tested against the pattern it makes with these as well as other groups. Sometimes, though not always, the pattern reflects a genealogical relationship among the organisms — at which point the inference of common ancestry is made.

Evolution and homology are closely related concepts but they are not circular: homology of a structure is diagnosed and tested by outside elements: structure, position, etc., and whether or not the pattern of distribution of the trait is genealogical. If the pattern of relationships looks like a genealogy, it would be perverse to deny that the trait reflects common ancestry or that an evolutionary relationship exist between the groups. Similarly, the closeness of the relationship between two groups of organisms is determined by the extent of homologous features; the more homologous features two organisms share, the more recent their common ancestor. Contrary to Wells's contention, neither the definition nor the application of homology to biology is circular.

Some formulations of the concept of homology appear to be circular, but as discussed above, because there is an external referent (the pattern that characteristics take across groups) that serves as an independent test, the concept, properly defined and understood, is not. Wells's claim that homology is circular reveals a mistaken idea of how science works. In science, ideas frequently are formulated by moving back and forth between data and theory, and scientists regularly distinguish between the definition of a concept and the evidence used to diagnose and test it."[/b]

1 Like

Re: Theory Of Evolution And Common Ancestry by sinequanon: 4:54pm On Dec 02, 2014
Weah

This is what I call an intelligent response to the OP. Thank you.

We can see that there are some molecular biologists who have reservations about HOW logic is used in philogenetics.

I hope you understand why I was unwilling to allow the trolls, who don't have the intelligence to even understand the question and issue, set the agenda in this thread.

Most of what you have quoted is just the author repeating his belief. We already know his standpoint. Repetition is not refutation. Stripping out the repetition and arm waving, these are his points..

What is truly important here is not whether textbooks describe homology circularly, but whether homology is used circularly in biology.

Because not all features that are similar in two organisms are necessarily inherited from a common ancestor, and not all features inherited from a common ancestor are similar, it is necessary to test structures before they can be declared homologous. To answer the question, "could this feature in these groups be inherited from a common ancestor?" scientists compare the feature across many groups, looking for patterns of form, function, development, biochemistry, and presence and absence.

i.e the morphological evidence can be tested independently against function and biochemical evidence (presence and absence is just a repetition of form/morphology).

But the two examples in the OP demonstrate shared form, function and biochemistry without common ancestry. The stripes on the moth have the same aposematic function as on the wasp, and the biochemistry of the slug has been laterally transferred from the algae.

If the pattern of relationships looks like a genealogy, it would be perverse to deny that the trait reflects common ancestry [size=18pt]or that an evolutionary relationship exist[/size] between the groups.

I have just given two examples which are not common ancestry.

He has cleverly slipped in "or evolutionary relationship" to cover his azz. Yes, the examples in the OP are evolutionary relationships, but they are NOT common ancestry. So he is defending evolution as a whole, here, not common ancestry. Same old tricks.

Some formulations of the concept of homology appear to be circular, but as discussed above, because there is an external referent (the pattern that characteristics take across groups) that [size=18pt]serves as an independent test[/size].

This is his only real point (which flies way over the heads of all the trolls in this thread, LOL).

What he is trying to say is that there appears to be a branching pattern, which is what you would expect with common ancestry -- and inductive logic is reasonable. He is confusing "inductive" and "independent".

However, other mechanisms can reflect branching. The moths and slugs shown in the OP will have different varieties, showing a branching of the horizontally obtained features. This does not mean that the features were inherited. It may reflect different algae and mimicry of different wasps.

Weah96:


I think you need a proper understanding of how traits are determined to be homologous, like the unique bones found only in birds and dinosaurs fossils.

http://ncse.com/creationism/analysis/circular-definitions

"This claim has a long history in the creationist literature, but is uniformly rejected by biologists as rooted in basic misunderstandings. The apparent homology of a single trait would not be treated as evidence of common descent. By examining multiple traits, all showing the same nested hierarchy of modifications of a common starting point, scientists can test hypotheses about common descent. There is nothing circular about this process."


Consequently, here is your answer. Feel free to replace the name Wells with yours, wherever it is found.

[b]"Wells claims that homology is used in a circular fashion by biologists because textbooks define homology as similarity inherited from a common ancestor, and then state that homology is evidence for common ancestry. Wells is correct: this simplified reading of homology is indeed circular. But Wells oversimplifies a complex system into absurdity instead of trying to explain it properly. Wells, like a few biologists and many textbooks, makes the classic error of confusing the definition of homology with the diagnosis of a homologous structure, the biological basis of homology with a procedure for discovering homology. In his discussion, he confuses not only the nature of the concept but also its history; the result is a discussion that would confuse. What is truly important here is not whether textbooks describe homology circularly, but whether homology is used circularly in biology. When homology is properly understood and applied, it is not circular at all.

Today, biologists still diagnose homologous structures by first searching for structures of similar form and position, just as pre-Darwinian biologists did. (They also search for genetic, histological, developmental, and behavioral similarities.) However, in our post-Darwin period, biologists define a homologous structure as an anatomical, developmental, behavioral, or genetic feature shared between two different organisms because they inherited it from a common ancestor. Because not all features that are similar in two organisms are necessarily inherited from a common ancestor, and not all features inherited from a common ancestor are similar, it is necessary to test structures before they can be declared homologous. To answer the question, "could this feature in these groups be inherited from a common ancestor?" scientists compare the feature across many groups, looking for patterns of form, function, development, biochemistry, and presence and absence.

If, considering all the available evidence, the distribution of characteristics across many different groups resembles a genealogical pattern, it is very likely that the feature reflects common ancestry. Future tests based on more features and more groups could change those assessments, however — which is normal in the building of scientific understanding. Nevertheless, when a very large amount of information from several different areas (anatomy, biochemistry, genetics, etc.) indicates that a set of organisms is genealogically related, then scientists feel confident in declaring the features that they share are homologous. Finally, while judgments of homology are in principle revisable, there are many cases in which there is no realistic expectation that they will be overturned.

So Wells is wrong when he says that homology assumes common ancestry. Whether a feature reflects common ancestry of two or more animal groups is tested against the pattern it makes with these as well as other groups. Sometimes, though not always, the pattern reflects a genealogical relationship among the organisms — at which point the inference of common ancestry is made.

Evolution and homology are closely related concepts but they are not circular: homology of a structure is diagnosed and tested by outside elements: structure, position, etc., and whether or not the pattern of distribution of the trait is genealogical. If the pattern of relationships looks like a genealogy, it would be perverse to deny that the trait reflects common ancestry or that an evolutionary relationship exist between the groups. Similarly, the closeness of the relationship between two groups of organisms is determined by the extent of homologous features; the more homologous features two organisms share, the more recent their common ancestor. Contrary to Wells's contention, neither the definition nor the application of homology to biology is circular.

Some formulations of the concept of homology appear to be circular, but as discussed above, because there is an external referent (the pattern that characteristics take across groups) that serves as an independent test, the concept, properly defined and understood, is not. Wells's claim that homology is circular reveals a mistaken idea of how science works. In science, ideas frequently are formulated by moving back and forth between data and theory, and scientists regularly distinguish between the definition of a concept and the evidence used to diagnose and test it."[/b]





Re: Theory Of Evolution And Common Ancestry by Weah96: 5:18pm On Dec 02, 2014
sinequanon:
Weah

This is what I call an intelligent response to the OP. Thank you.

We can see that there are some molecular biologists who have reservations about HOW logic is used in philogenetics.

I hope you understand why I was unwilling to allow the trolls, who don't have the intelligence to even understand the question and issue, set the agenda in this thread.

Most of what you have quoted is just the author repeating his belief. We already know his standpoint. Repetition is not refutation. Stripping out the repetition and arm waving, these are his points..





i.e the morphological evidence can be tested independently against function and biochemical evidence (presence and absence is just a repetition of form/morphology).

But the two examples in the OP demonstrate shared form, function and biochemistry without common ancestry. The stripes on the moth have the same aposematic function as on the wasp, and the biochemistry of the slug has been laterally transferred from the algae.



I have just given two examples which are not common ancestry.

He has cleverly slipped in "or evolutionary relationship" to cover his azz. Yes, the examples in the OP are evolutionary relationships, but they are NOT common ancestry. So he is defending evolution as a whole, here, not common ancestry. Same old tricks.



This is his only real point (which flies way over the heads of all the trolls in this thread, LOL).

What he is trying to say is that there appears to be a branching pattern, which is what you would expect with common ancestry -- and inductive logic is reasonable. He is confusing "inductive" and "independent".

However, other mechanisms can reflect branching. The moths and slugs shown in the OP will have different varieties, showing a branching of the horizontally obtained features. This does not mean that the features were inherited. It may reflect different algae and mimicry of different wasps.


Yea, but you're still only looking at singular traits in the slug and moth. Stripe pattern is one trait. In the slug, exogenous DNA is another. It's unreasonable to infer common descent simply by isolating individual traits. Unless, of course, these traits originate in germ cells.
Re: Theory Of Evolution And Common Ancestry by Kay17: 5:39pm On Dec 02, 2014
sinequanon:


It is assumed because it is assumed.

Good answer.

Anyone else?

In other words, it was not considered. But nonetheless Darwin wants an exciting theory regardless the possible foundations.

The possibility of horizontal transfer is not in doubt nor disproven, but it is not just considered. If the possibilty is more likely, then a consideration would be made as to whether it can be integrated into the evolution theory.
Re: Theory Of Evolution And Common Ancestry by sinequanon: 5:45pm On Dec 02, 2014
Weah96:


Yea, but you're still only looking at singular traits in the slug and moth. Stripe pattern is one trait. In the slug, exogenous DNA is another. It's unreasonable to infer common descent simply by isolating individual traits. Unless, of course, these traits originate in germ cells.

Non-inherited singular traits or behaviours could give rise to multiple non-inherited traits and behaviours. In fact, the slug example shows two traits -- the accommodation of chloroplasts from the algae and the supposed genetic transfer from the algae. It is unlikely these happened both at the same time. It makes sense that one trait can spawn several supporting traits. Similar environments and functions can also spawn similar traits by any method.
Re: Theory Of Evolution And Common Ancestry by Weah96: 6:20pm On Dec 02, 2014
sinequanon:


Non-inherited singular traits or behaviours could give rise to multiple non-inherited traits and behaviours. In fact, the slug example shows two traits -- the accommodation of chloroplasts from the algae and the supposed genetic transfer from the algae. It is unlikely these happened both at the same time. It makes sense that one trait can spawn several supporting traits. Similar environments and functions can also spawn similar traits by any method.



HGT occurs between prokaryotes, prokaryotes and eukaryotes, and between microbial eukaryotes. It hasn't been observed between full sized eukaryotes.

For this reason, phylogenetic trees depicting common ancestry in microbes of either archea, bacteria, or eukaryota ALREADY take this phenomenon into consideration.

However, there is no justification for implying HGT between dinosaurs and birds, so it's ignored.
Re: Theory Of Evolution And Common Ancestry by sinequanon: 6:40pm On Dec 02, 2014
Weah96:
HGT occurs between prokaryotes, prokaryotes and eukaryotes, and between microbial eukaryotes. It hasn't been observed between full sized eukaryotes.

So what? Two "full-sized" eukaryotes can obtain the same trait from the same prokaryote.

Weah96:
For this reason, phylogenetic trees depicting common ancestry in microbes of either archea, bacteria, or eukaryota ALREADY take this phenomenon into consideration.

This is relatively recent and calls into question Darwin's "last universal ancestor" hypothesis.

Weah96:
However, there is no justification for implying HGT between dinosaurs and birds, so it's ignored.

Yes there is. Your premise that shared traits must have been passed from dinosaur to bird is incorrect. Shared traits could come from a prokaryote. In fact, the slug in the OP shares its trait with other species.



Elysia viridis



Elysia chlorotica

The shared trait is not from common ancestry.
Re: Theory Of Evolution And Common Ancestry by Weah96: 7:12pm On Dec 02, 2014
sinequanon:


So what? Two "full-sized" eukaryotes can obtain the same trait from the same prokaryote.



This is relatively recent and calls into question Darwin's "last universal ancestor" hypothesis.



Yes there is. Your premise that shared traits must have been passed from dinosaur to bird is incorrect. Shared traits could come from a prokaryote. In fact, the slug in the OP shares its trait with other species.

I never said that traits were passed from dinosaurs to birds. I said that common ancestry is the factor considered, not HGT. It's possible that birds and dinosaurs evolved from the same ancestor. That's not the same statement as birds descending FROM dinosaurs.

The possibility does exist that two non microbial eukaryotes could have obtained a trait from the same prokaryote. In fact, the mitochondria of plants and animals are eerily similar to a prokaryotic cell engulfed by endocytosis in the past.

Would it be reasonable to conclude that humans aren't related by common ancestry because our shared mitochondria could have originated from a bacteria?

Again, that's why one or two traits don't suffice. That's also why it's irrational to suggest that that a multitude of similar traits could have all arisen as a result of one HGT event.

I told you what your original question was from the beginning of this thread. You went around in circles, only to arrive at the question I asked on page one.

Remember, how are phylogenetic trees constructed in the face of HGT?
Re: Theory Of Evolution And Common Ancestry by sinequanon: 7:26pm On Dec 02, 2014
Weah96:


I never said that traits were passed from dinosaurs to birds. I said that common ancestry is the factor considered, not HGT.

You keep losing track. This is what the OP says. Why are you repeating it?

wrt to dinosaur passing traits to birds, we were talking in the context of HGT. You said that you can ignore HGT because it has not been observed from eukaryote to eukaryote, forgetting that it needn't be direct. When I point this out, you go back and repeat that HRT is not being considered? So it is not being considered, because it is not being considered? I think you need to go and organize your ideas, and stop going round in circles. Or perhaps the whole thing is too complicated for you to keep track of.

Weah96:
I told you what your original question was from the beginning of this thread. You went around in circles, only to arrive at the question I asked on page one.

Remember, how are phylogenetic trees constructed in the face of HGT?

Nope, it is you losing track and going round in circles and winding up with the wrong question.

Anyway, I don't think you are going to understand. But the author you quoted did attempt to address the point. He's probably the one who could answer my rebuttal.

I'll leave it there.
Re: Theory Of Evolution And Common Ancestry by Weah96: 7:59pm On Dec 02, 2014
sinequanon:


You keep losing track. This is what the OP says. Why are you repeating it?

wrt to dinosaur passing traits to birds, we were talking in the context of HGT. You said that you can ignore HGT because it has not been observed from eukaryote to eukaryote, forgetting that it needn't be direct. When I point this out, you go back and repeat that HRT is not being considered? So it is not being considered, because it is not being considered? I think you need to go and organize your ideas, and stop going round in circles. Or perhaps the whole thing is too complicated for you to keep track of.



Nope, it is you losing track and going round in circles and winding up with the wrong question.

Anyway, I don't think you are going to understand. But the author you quoted did attempt to address the point. He's probably the one who could answer my rebuttal.

I'll leave it there.

You were putting words in my mouth, so to speak, that's why I had to make my statement clear. I wasn't restating anything.

I asked you about human mitochondria being an ancient bacteria that was engulfed by a cell. On what grounds then are humans similar since this bacteria could have been transferred to two or more different species of human beings? Remember you said that one HGT event in two different animals could potentially lead to a multitude of similarities down the road.

Maybe we are all distinct species of human beings and our perceived similarities are due to the same bacteria being ingested by our individual ancestors.
Re: Theory Of Evolution And Common Ancestry by sinequanon: 8:24pm On Dec 02, 2014
Weah96:


You were putting words in my mouth, so to speak, that's why I had to make my statement clear. I wasn't restating anything.

The example I gave was of the theory that birds are descended from early reptiles. So the example is about traits passed from early reptiles to birds.

Then, out of the blue, you suddenly decide to reconstruct MY example without warning and later tell me you were talking about common ancestry of birds and reptiles, but not reptiles being the ancestors of birds. Meanwhile, you think you can clarify the non-sequitur by repeating bits of the OP?

I don't know how you expect me to follow this jumping around.

Weah96:
I asked you about human mitochondria being an ancient bacteria that was engulfed by a cell. On what grounds then are humans similar since this bacteria could have been transferred to two or more different species of human beings?

Humans are similar in lots of respects. Visually, genetically, morphologically, behaviour-wise.

Weah96:
Remember you said that one HGT event in two different animals could potentially lead to a multitude of similarities down the road.

I can't see any connection between this and your last sentence.

Weah96:
Maybe we are all distinct species of human beings and our perceived similarities are due to the same bacteria being ingested by our individual ancestors.

If "species" is defined in terms of mitochondrial origin, then it would follow that this is quite possible. But I don't think that that is one of the many definitions of "species", in which case it could still be possible, but would be a non-sequitur to our discussion on mitochondria.
Re: Theory Of Evolution And Common Ancestry by Weah96: 8:35pm On Dec 02, 2014
sinequanon:


Humans are similar in lots of respects. Visually, genetically, morphologically, behaviour-wise.


Lemme put your words in quotation marks, so that perhaps your memory can be jolted.

"Non-inherited singular traits or behaviours could give rise to multiple non-inherited traits and behaviours."

You wrote that. Now, if the mitochondrion was once a singular "non inherited" bacteria, on what grounds can you say that humans are similar? All of those similarities you list here could have occurred because different species of human beings were affected by the same bacteria.
Re: Theory Of Evolution And Common Ancestry by sinequanon: 8:45pm On Dec 02, 2014
Weah96:


Lemme put your words in quotation marks, so that perhaps your memory can be jolted.

"Non-inherited singular traits or behaviours could give rise to multiple non-inherited traits and behaviours."

You wrote that. Now, if the mitochondrion was once a singular "non inherited" bacteria, on what grounds can you say that humans are similar?

I've answered this. Why are you repeating yourself?

I can say humans are similar visually, genetically, morphologically, behaviour-wise.

Weah96:
All of those similarities you list here could have occurred because different species of human beings were affected by the same bacteria.


And?

I have no clue what your point is.

Unless you are now agreeing that similarities in humans need not all be homologous?
Re: Theory Of Evolution And Common Ancestry by Weah96: 9:22pm On Dec 02, 2014
sinequanon:


I've answered this. Why are you repeating yourself?

I can say humans are similar visually, genetically, morphologically, behaviour-wise.



And?

I have no clue what your point is.

Unless you are now agreeing that similarities in humans need not all be homologous?

You're way out there dude. So common ancestry can't even be inferred between human beings again? HAHAHA.

How do you determine which similarities are homologous among human beings and which ones are not?
Re: Theory Of Evolution And Common Ancestry by sinequanon: 9:52pm On Dec 02, 2014
Weah96:


You're way out there dude. So common ancestry can't even be inferred between human beings again? HAHAHA.

How do you determine which similarities are homologous among human beings and which ones are not?

Your problem is that you find it difficult to string together a logical argument.

You don't even know how to negate a statement. This is a basic skill in scientific and logical argument.

All the balls could belong to Joe.

Natural converse (i.e if the above is false) is this...

Some of the balls may not belong to Joe.

Not weah logic...

None of the balls belong to Joe.

How can we debate if you can't do simple logic?

Look at this sentence again, and try to negate it properly..

All of those similarities you list here could have occurred because different species of human beings were affected by the same bacteria.
Re: Theory Of Evolution And Common Ancestry by sinequanon: 10:35pm On Dec 02, 2014
Weah96:
How do you determine which similarities are homologous among human beings and which ones are not?

Use tests that distinguish between HGT and VGT and other mechanisms that lead to morphological similarities.

If there are no reliable tests for a particular trait, then you don't just say, "HAHAHA, I'll pick VGT because I am not used to anything else."

It is unlikely that there are no tests for ALL the traits.

You are the one that said..

All of those similarities you list here could have occurred because different species of human beings were affected by the same bacteria.

Presumably, you mean "potentially could have occurred". In which case, you investigate, considering ALL the options, and find out which ones may or may not originate from heredity. You don't just ASSUME HEREDITY.
Re: Theory Of Evolution And Common Ancestry by Weah96: 6:16am On Dec 03, 2014
sinequanon:


Your problem is that you find it difficult to string together a logical argument.

You don't even know how to negate a statement. This is a basic skill in scientific and logical argument.

All the balls could belong to Joe.

Natural converse (i.e if the above is false) is this...

Some of the balls may not belong to Joe.

Not weah logic...

None of the balls belong to Joe.

How can we debate if you can't do simple logic?

Look at this sentence again, and try to negate it properly..

All of those similarities you list here could have occurred because different species of human beings were affected by the same bacteria.


Remove your head from your an)us and take a deep breath. You'll feel a lil better, trust me.
Re: Theory Of Evolution And Common Ancestry by Weah96: 6:52am On Dec 03, 2014
sinequanon:


Use tests that distinguish between HGT and VGT and other mechanisms that lead to morphological similarities.

If there are no reliable tests for a particular trait, then you don't just say, "HAHAHA, I'll pick VGT because I am not used to anything else."

It is unlikely that there are no tests for ALL the traits.

You are the one that said..



Presumably, you mean "potentially could have occurred". In which case, you investigate, considering ALL the options, and find out which ones may or may not originate from heredity. You don't just ASSUME HEREDITY.

Before we proceed, you must state what "these other mechanisms that lead to morphological similarities are.

You can no longer disguise nonsense as eloquence, state these "other mechanisms" here just like you stated HGT and we'll go from there.

Whole genome analyses are used to separate analogous genes from homologous ones, but according to you, evidence from genes cannot imply heredity. That's what your OP says anyway.

We're not allowed to examine similarities, not even a multitude of similarities and patterns of organization. We're not allowed to use genes.

That's why I asked the question. What possible test can there be other than prayer?

Genes are used to determine paternity, but they're off limits as far as common descent is concerned. Does that make sense in your head?

1 Like

Re: Theory Of Evolution And Common Ancestry by sinequanon: 10:45am On Dec 03, 2014
Weah96:


Before we proceed, you must state what "these other mechanisms that lead to morphological similarities are.

Well, we are not going to proceed as you have shown yourself to be rather too thick.
Re: Theory Of Evolution And Common Ancestry by Weah96: 3:01pm On Dec 03, 2014
sinequanon:


Well, we are not going to proceed as you have shown yourself to be rather too thick.

I guess you've run out of mechanisms, or perhaps you read that nonsense you posted in your OP again.

2 Likes

Re: Theory Of Evolution And Common Ancestry by plaetton: 6:51pm On Dec 03, 2014
Weah96:


I guess you've run out of mechanisms, or perhaps you read that nonsense you posted in your OP again.

Word salads can only take you so far before you run out of gas, literally and figuratively.
cheesy

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