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Author Topic:   Extent of Mutational Capability
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Message 61 of 279 (793154)
10-22-2016 8:44 AM
Reply to: Message 54 by CRR
10-21-2016 8:51 PM


Re: What is a "kind"?
Hi CRR,
The definition of kind *does* have to have a solid definition. It can be as complicated and messy as the definition of species, or it can be as simple as you like, or it can be anywhere in between, but it must have a clear and unambiguous definition. Without such a definition these claims from your Message 28 and Message 35 can't be discussed:
CRR in Message 28 writes:
However we have never observed evolution from one kind into another.
CRR in Message 35 writes:
Who claims that one kind can evolve into another? Evolutionists, that's who!
You *do* offer a definition:
The definition I favour is "those animals/plants that could interbreed immediately following creation". There has been much speciation and differentiation since then and it is often difficult to precisely define boundaries between kinds.
Here's a list of the issues I see with your definition. Some have already been noted:
  1. Your definition makes specific reference to creation, which isn't a concept with any scientific foundation. The underlying assumption in all the science threads is that discussion will have a scientific foundation. If you believe you can establish a scientific foundation for creation then you should propose another thread where you do that, then return to this one.
  2. Your definition is specific to sexual species. Do you want to extend the definition to include asexual species like bacteria?
  3. Your definition includes speciation within kinds, which means you accept that an original interbreeding population of a single kind could gradually become two or more populations that cannot interbreed with one another. This seems to make kind superfluous and accept evolution's view of speciation.
  4. Your definition is vague. For example, your definition doesn't exclude mammal as a kind, but an original mammal kind could have gradually become many, many different mammal species within the mammal kind and that would still fit within your definition. But it is unlikely that you agree that kind applies to such a high level of classification as mammal.
Others will break your definition down differently, and that's fine, I see no reason to fix on a single analysis. But I do think it necessary that kind be given a more precise definition and a more direct connection to the world that, as a purportedly scientific concept, it is required to have.
Please, no replies to this message.

--Percy
EvC Forum Director

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Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 62 of 279 (793156)
10-22-2016 9:21 AM


I note that it is perfectly possible for CRR to be wrong about genetics without having an operational definition of "kind", so perhaps he should just stick to that.

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herebedragons
Member (Idle past 857 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


(2)
Message 63 of 279 (793157)
10-22-2016 9:22 AM
Reply to: Message 54 by CRR
10-21-2016 8:51 PM


Re: What is a "kind"?
The biological species concept is popular but many use the phylogenetic concept and it is often difficult to precisely define boundaries between species. There are many cases where animals classified as separate species can produce viable and fertile offspring, e.g. lion-tiger, although their offspring is more often infertile. There are also cases of cross genera offspring such as the wholpin.
I think you misunderstand the Biological Species concept... it does not state that different species cannot produce viable offspring under any circumstances; it states that species are groups of organisms that interbreed in nature and are reproductively isolated from other such groups. So... lions and tigers ARE separate species since they do not interbreed in nature - even though they can be forced to do so in captivity. So is the case with most of your other examples of separate species interbreeding.
Yes, of course there are problems with species concepts, for example, the Biological Species Concept does not apply to clonal organisms. There are complications when determining where the boundary between two species is - since there is more a continuum between species than there is a hard boundary.
Only partly as a joke, one definition is that a species is "whatever a competent taxonomist says is a species."
This is kind of true. Classification of species is a human endeavor with the purpose of making communication about biological life more precise. When a new species or a reclassification of a group is is proposed it comes with solid reasons/evidence for the new classification. Often times the proposal is argued about in the literature for years until a consensus is reached. But again, all this is done with the purpose of making communication about the organisms more effective.
"Kinds" is a completely different concept. The purpose of defining "kinds" seems to make communication more ambiguous. There is just no rigorous methodology for determining "kind." Notice how open-ended the following definition is:
"those animals/plants that could interbreed immediately following creation"
How could you possibly determine that they could interbreed immediately following creation. This definition is completely unusable. A better, but still problematic, definition would be that each pair of animals on the ark represented a "kind." Still, how could that help communication?
What Creationists want to accomplish by proposing definitions of "kind," despite their common rhetoric, is to discredit evolution - not to provide a better understanding of how nature works. Even more important is to establish that man is a separate "kind" and did not evolve from "lesser" creatures. These goals do not advance our understanding of how life works, they only serve to establish that a particular interpretation and understanding of scripture is correct and infallible and that the intention and thoughts of a people long gone are so clear to us. That is why the concept of "kind" is not considered scientific, but a form of apologetics.
It is the nature of scientific research that sometimes (often) we have to adjust what we think to be true.
Why is that not the nature of theology as well?
HBD

Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca
"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.
Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.

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JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


(1)
Message 64 of 279 (793158)
10-22-2016 9:23 AM
Reply to: Message 54 by CRR
10-21-2016 8:51 PM


Re: What is a "kind"?
I think this shows that current taxonomic classifications are only an approximation to biological reality.
All classification schemes and all models are approximations to reality.
In this case, the current taxonomic schemes have been conclusively demonstrated to be excellent models of biological reality.
It looks as if you are promulgating the old YEC tactic of "we don't know everything therefore we know nothing". Yes, our classification is not perfect. It's still pretty near perfect and extremely useful.

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herebedragons
Member (Idle past 857 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


Message 65 of 279 (793160)
10-22-2016 9:34 AM
Reply to: Message 62 by Dr Adequate
10-22-2016 9:21 AM


True. But he can't claim that one "kind" has never been observed turning into another "kind" without a working definition, because we would have no way to determine if the statement was correct.
HBD

Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca
"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.
Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.

This message is a reply to:
 Message 62 by Dr Adequate, posted 10-22-2016 9:21 AM Dr Adequate has not replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 66 of 279 (793161)
10-22-2016 9:46 AM
Reply to: Message 63 by herebedragons
10-22-2016 9:22 AM


Re: What is a "kind"?
What Creationists want to accomplish by proposing definitions of "kind," despite their common rhetoric, is to discredit evolution...
And fit all the animals on the ark.

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jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 67 of 279 (793162)
10-22-2016 9:59 AM
Reply to: Message 54 by CRR
10-21-2016 8:51 PM


Re: What is a "kind"?
CRR writes:
The definition I favour is "those animals/plants that could interbreed immediately following creation".
If that is your definition it would exclude humans as a kind. It would exclude all mammals as a kind. It would exclude all reptiles as a kind. It would exclude all dinosaurs as a kind. It would exclude all birds as a kind. It would exclude all flowers, all trees, all vegetables, all fruits, all nuts as kinds.
The evidence and all of the evidence shows that none of those critters existed immediately following creation.

My Sister's Website: Rose Hill Studios My Website: My Website

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RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 68 of 279 (793166)
10-22-2016 12:05 PM
Reply to: Message 41 by CRR
10-21-2016 2:23 AM


Re: Block quotes
Welcome to the fray CRR
How do you do those block quotes?
There are two different ways to do quotes.
... as you are new here, some posting tips:
type [qs]quotes are easy[/qs] and it becomes:
quotes are easy
and you can type [qs=RAZD]quotes are easy[/qs] and it becomes:
RAZD writes:
quotes are easy
or type [quote]quotes are easy[/quote] and it becomes:
quote:
quotes are easy
also check out (help) links on any formatting questions when in the reply window.
For other formatting tips see Posting Tips
For a quick overview see EvC Forum Primer
If you have problems with replies see Report Discussion Problems Here 3.0
I like to use the [qs] for answering posts and the [quote] form for quoting from articles and references.
Enjoy

we are limited in our ability to understand
by our ability to understand
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to share.


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ringo
Member (Idle past 411 days)
Posts: 20940
From: frozen wasteland
Joined: 03-23-2005


Message 69 of 279 (793167)
10-22-2016 12:09 PM
Reply to: Message 54 by CRR
10-21-2016 8:51 PM


Re: What is a "kind"?
CRR writes:
Similarly there is no universally accepted definition of kind. The definition I favour is "those animals/plants that could interbreed immediately following creation".
The Bible uses the word "kind" much the same way as we do - e.g. "What kind of dog is that?"
quote:
Leviticus 19:19 Ye shall keep my statutes. Thou shalt not let thy cattle gender with a diverse kind: thou shalt not sow thy field with mingled seed: neither shall a garment mingled of linen and woollen come upon thee.
This suggests that different kinds can interbreed but you shouldn't let them - e.g. a poodle can interbreed with a spaniel but you shouldn't let it.
So the creationist attempt to use "kind" as some sort of barrier to evolution has no merit either biologically or biblically.

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RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(2)
Message 70 of 279 (793168)
10-22-2016 12:54 PM
Reply to: Message 28 by CRR
10-21-2016 12:12 AM


Micro- and macroevolution are not so-called. The terms were coined by an evolutionist and I have found them in common use even at university level. However there is no precise universally agreed definition. Treat them as general rather than exact terms.
Micro-evolution is the evolution within a species population.
Macro-evolution is the divergence of species that no longer share genetic material via interbreeding.
ie speciation is the demarcation line.
There is nothing that will actively stop mutations, although we also know that in some circumstances mutations are actively promoted in hot spots. ...
Correct, mutation rates vary with location.
... There is however a passive barrier and that is the extreme rarity of beneficial mutations within the space of all possibilities. ...
Irrelevant. Beneficial mutations occur.
... A change that requires several mutations before a benefit is produced are essentially beyond the reach of [neo-]Darwinian evolution.
Demonstrably false. Neutral mutations and non-lethal but harmful (handicapping) mutations can persist in the breeding population, especially when carried on a beneficial gene.
This allows later mutations to build beneficial aspects on them, especially when the ecology changes. There is actual observed documented instances of this happening (E.coli cloning experiment).
Perhaps you are referring to Irreducible Complexity ... ? see ID acid test
Indeed there is considerable variation possible within the dog kind. Similarly from hybrids we can infer that all cats, from tabby to tiger, are all part of the cat kind. ...
Let's talk about clades and cladistics:
With multiple speciation events, a pattern is formed that looks like a branching bush or tree: the tree of descent from common ancestor populations. Each branching point is a node for a clade of the parent species at the node point and all their descendants, and with multiple speciation events we see a pattern form of clades branching from parent ancestor species and nesting within larger clades branching from older parent ancestor species.
Where A, B, C and G represent speciation events and the common ancestor populations of a clade that includes the common ancestor species and all their descendants: C and below form a clade that is part of the B clade, B and below form a clade that is also part of the A clade; G and below also form a clade that is also part of the A clade, but the G clade is not part of the B clade.
The process of forming a nested hierarchy by descent of new species from common ancestor populations, via the combination of anagenesis and cladogenesis, and resulting in an increase in the diversity of life, is what biologists call macroevolution.
A "kind" would then be a clade with no previous ancestor. If (A) did not exist then (B) and (G) would be different "kinds" but (C) would still be descendant from (B).
... However we have never observed evolution from one kind into another.
Nor does evolution ever in any way claim that this occurs -- because all evolution occurs within a species population, the descendants will always be offspring of their clade parent population: dogs will always be dogs and cats will always be cats.
Nor would there be selection pressure in such direction, because all evolution needs accomplish is convergent evolution as noted in Message 26:
quote:
When selection pressure pushes for development of an animal similar to another known animal what you end up with is convergent evolution. For example, flying squirrels and sugar gliders:
Flying squirrels are placental mammals while Sugar gliders are marsupial mammals, their common ancestor is back at the division of mammalia into these two fundamentally different branches and while they have superficially similar appearances their internal physiologies are different and they cannot interbreed.
There are many examples of convergent evolution.
Gene merging or gene duplication and conversion has never been observed. The closest they have come is identifying a family of similar genes that are assumed to have evolved from a common ancestor.
Gene duplication has been observed in formation of polyploidy species. Gene fusion has been identified in several species, not just because the genes are similar but because they carry neutral insert markers that are identical, and the chance of that occurring is virtually zero. Assuming common origin is a robust and valid conclusion.
Enjoy

we are limited in our ability to understand
by our ability to understand
RebelAmerican☆Zen☯Deist
... to learn ... to think ... to live ... to laugh ...
to share.


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RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 71 of 279 (793172)
10-22-2016 5:48 PM
Reply to: Message 54 by CRR
10-21-2016 8:51 PM


What is a "species"?
First I'd like to ask what is a species?
Although some people may wish for a black-and-white criterion for defining species, this is unrealistic. [ Encyclopedia of Life ]
See Definition of Species for a discussion of this fascinating topic.
The biological species concept is popular but many use the phylogenetic concept and it is often difficult to precisely define boundaries between species. ...
It is difficult to use a biological or genetic definition of species for fossils, and the biological definition cannot be used on asexual species, and in these cases a phylogenetic definition is more useful -- to people (other species don't seem to care ... beyond 'mate-able' and 'non-mate-able').
It is also worth noting that the phlogenetic definition works well with cladistics even though it developed from classic taxonometric classifications.
... There are many cases where animals classified as separate species can produce viable and fertile offspring, e.g. lion-tiger, although their offspring is more often infertile. ...
As in camels and llamas, but as has been pointed out there is also an element of opportunity, and there are instances where new species arise from mating of distantly related populations. So yes there is not black and white answer.
But we also need to ask what is the purpose of making these definitions? What are they used for? And this is a purely human occupation in trying to make rational sense of the natural world, how we organize the information available in a way that makes sense.
Now, I hope you would agree that the phylogenetic tree that shows clades and the patterns of descent of breeding populations is clearer when we label populations with the names of species.
I think this shows that current taxonomic classifications are only an approximation to biological reality.
Of course, but a fairly accurate one when we can also construct a genetic tree and find that there are only a few areas of disagreement, that the basic picture is correct, and with two sources of such information that otherwise would not need to agree, fairly robust. Changes found were minor alterations not whole-sale revisions.
Similarly there is no universally accepted definition of kind. ...
And I have not seen one (1) definition accepted by two creationists that is workable in identifying a single 'kind' - rather it is opinion (I don't know what a 'kind' is, but I know one when I see one). Again I refer you to cladistics and clades that, imho, is the clearest example of what creationists mean by 'kind' -- as I noted in Message 70:
quote:
Let's talk about clades and cladistics:
With multiple speciation events, a pattern is formed that looks like a branching bush or tree: the tree of descent from common ancestor populations. Each branching point is a node for a clade of the parent species at the node point and all their descendants, and with multiple speciation events we see a pattern form of clades branching from parent ancestor species and nesting within larger clades branching from older parent ancestor species.
Where A, B, C and G represent speciation events and the common ancestor populations of a clade that includes the common ancestor species and all their descendants: C and below form a clade that is part of the B clade, B and below form a clade that is also part of the A clade; G and below also form a clade that is also part of the A clade, but the G clade is not part of the B clade.
The process of forming a nested hierarchy by descent of new species from common ancestor populations, via the combination of anagenesis and cladogenesis, and resulting in an increase in the diversity of life, is what biologists call macroevolution.
A "kind" would then be a clade with no previous ancestor. If (A) did not exist then (B) and (G) would be different "kinds" but (C) would still be descendant from (B).
... It is the nature of scientific research that sometimes (often) we have to adjust what we think to be true.
Indeed, it is the nature of rational thought that "sometimes (often) we have to adjust what we think to be true" ... and that this holds for all areas of thought, even including religious opinions.
Enjoy

we are limited in our ability to understand
by our ability to understand
RebelAmerican☆Zen☯Deist
... to learn ... to think ... to live ... to laugh ...
to share.


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Stile
Member
Posts: 4295
From: Ontario, Canada
Joined: 12-02-2004


(2)
Message 72 of 279 (793185)
10-23-2016 11:13 AM
Reply to: Message 48 by Gregory Rogers
10-21-2016 11:31 AM


Check Archive History for Iron-Sharpens-Iron
Gregory Rogers writes:
I would be interested to see where the logical course of the thread is going - although, by now I certainly have my answer, at least from a Darwinist perspective. I am a little surprised there are not more creationist or ID-ers on the site - I was hoping for a more 'iron sharpens iron' experience, where posts could be tested from both sides.
Yeah, so would we
It used to be more-even. But, well, creationists are lowering and lowering in numbers everyday.
You are free to have your own opinion, of course. But creationists vs evolutionists really is similar to flat-earthers vs globe-earthers.
There will always be a fringe group that believe whatever they want to believe. But the facts of the matter is that evolution happens, and common ancestors exist. Details and minute specifics are still being evaluated (just as we haven't mapped out every square-inch of the planet, yet either). But the general idea of descent-with-modification-through-mutations-and-natural-selection is so widely tested and verified that it's rather silly to not accept it.
You don't have to take my word for it, though. Just keep doing exactly what you're doing (looking for honest answers) and you'll see it soon enough. Reality doesn't require any shadiness in it's explanations. Even children can identify a shuckster in a few moments after checking the facts.
So, basically, reality has already beaten down most of the 'honest creationists.' There simply isn't much of a group left to have an 'iron-sharpens-iron' discussion. Those have already taken place, the iron has already been sharpened, the result has already fallen into place. You are, unfortunately, simply late to the discussion.
In short, apart from rebuttals to existing posts, at this stage I would like to hear the ID/Creationist view on the extent and 'elasticity' of genetic mutations.
We would like to hear any ID/Creationist views as well. After all, it's what keeps forums like this going.
This Evo/Creo debate forum is very open with extremely balanced moderation. No posts get deleted. No users get deleted. Everything is always left up for everyone/anyone to read and review themselves. People do get suspended for breaking rules. And permanent bans do happen, but they are extremely rare and well documented to the public for their reasons.
Most Creo-ran sites (like evolutionfairytales.com) are not so open to discussion. They'll ban opinions they do not like almost immediately. They'll delete posts so they can act like an opposing view doesn't even exist. There's no discussion, or warnings, or honesty. It's all just smoke and mirrors to keep the act up.
If not, however, then perhaps this thread can suffer the 'coup de grace'; and I will duly go on to my next question in a new thread.
I wouldn't worry about it.
You're doing fine.
Feel free to talk or discuss anything you'd like. We're eager (as you can see) for discussion so we'll create our own if necessary.
The rules are more strict on staying-on-topic around here (keeps things organized as much as possible). Not so strict on new-topics-to-discuss. So if you have a new topic, feel free to start another thread. The promotion-system for new threads is basically a way to prevent spammers and bots. it's not meant to dissuade anyone from coming up with new ideas to talk about.
Feel free to look around, the archives are full of some of the iron-sharpens-iron discussions you were looking for. Try looking into the past on any forum that interests you (Biological Evolution, Is It Science?, Creation/Evolution Miscellany... would be good places to start for this sort of topic, I'd guess). Possibly around the early-2000's or so for when the population of the board was 'more even' between creo and evo. Peronally, I like the Faith and Belief forum. But that's just me.
Hope you find what you're looking for.
Have fun!

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CRR
Member (Idle past 2242 days)
Posts: 579
From: Australia
Joined: 10-19-2016


Message 73 of 279 (793194)
10-23-2016 4:53 PM
Reply to: Message 54 by CRR
10-21-2016 8:51 PM


Re: What is a "kind"?
I have provided a definition of kind as per Percy's request [#45] and in response to others. The definition I favour is "those animals/plants that could interbreed immediately following creation". You might not agree with it but you now have one.
RAZD has also proposed a definition "A "kind" would then be a clade with no previous ancestor." I think this is workable so long as you suspend the inherent assumption of cladistics that all clades are subsets of the LUCA clade. (Please note that RAZD does not accept that such kinds actually exist.)
Now I will try to get back to Greg's question about the extent of mutational capacity.

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Tangle
Member
Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


(2)
Message 74 of 279 (793196)
10-23-2016 5:36 PM
Reply to: Message 73 by CRR
10-23-2016 4:53 PM


Re: What is a "kind"?
CRR writes:
I have provided a definition of kind as per Percy's request [#45] and in response to others. The definition I favour is "those animals/plants that could interbreed immediately following creation". You might not agree with it but you now have one.
Why would you think that a personal definition with no factual corroboration would be of any use or interest to anyone but you?
It's not enough to shrug it off with 'this is what I believe', if you wish to make progress here you need to support your claim.

Je suis Charlie. Je suis Ahmed. Je suis Juif. Je suis Parisien.
Life, don't talk to me about life - Marvin the Paranoid Android
"Science adjusts it's views based on what's observed.
Faith is the denial of observation so that Belief can be preserved."
- Tim Minchin, in his beat poem, Storm.

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herebedragons
Member (Idle past 857 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


(2)
Message 75 of 279 (793197)
10-23-2016 9:59 PM
Reply to: Message 73 by CRR
10-23-2016 4:53 PM


Re: What is a "kind"?
Now I will try to get back to Greg's question about the extent of mutational capacity.
But Greg's question is essentially "are there genetic limits that prevent one kind of creature from becoming another kind?" So without a useful definition of "kind" it is pretty hard to really address that question. For example, are wolves and foxes different kinds? Well, lets see... were they able to interbreed immediately after the creation? How could you possibly determine that?
I think RAZD's definition is very good: "A "kind" would then be a clade with no previous ancestor." This can be determined and discussed.
I think this is workable so long as you suspend the inherent assumption of cladistics that all clades are subsets of the LUCA clade.
If I pointed to any living or fossilized organism and asked "what came before this organism?" The answer would be "a similar organism. Not one that was exactly like it, but one that was slightly different." So it is a perfectly valid assumption that every organism and every group of organisms has a ancestral organism or group of organisms. It then becomes an hypothesis as to what those ancestral groups were, but the assumption that there was an ancestral group is quite valid.
**There is just no scientific reason why we should assume that any clade should have no previous ancestor.
However, you are arguing that some clades do not have previous ancestors and that the founding group of that clade was the original interbreeding population at the time of creation. So that is what you need to offer support for. What clades have no previous ancestor and what evidence supports those hypotheses? Failure of two species to produce fertile offspring does not indicate they are members of separate clades without a common ancestor since we have species that do not interbreed that are clearly part of the same clade.
Defining the term "kind" as "those animals/plants that could interbreed immediately following creation" is a moving target type of answer; it can be stretched and fit to any hypothesis you wish to propose since there is no way to determine what "kinds" even existed immediately following creation, let alone if they could have interbred.
HBD

Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca
"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.
Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.

This message is a reply to:
 Message 73 by CRR, posted 10-23-2016 4:53 PM CRR has not replied

  
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