Ring Species. How do creationists account for this?

[Deaver]

I have no problem accepting anything, so long as it's reasonable and based on reality.

And I would submit that it is reasonable to believe that there is a creator of everything we see around us. Someday we will both know, unless of course there is no creator, in which case it doesn't really make a difference, does it!

 

[FrenchyBearpaw]

And I would submit that it is reasonable to believe that there is a creator of everything we see around us. Someday we will both know, unless of course there is no creator, in which case it doesn't really make a difference, does it!

Ok.

 

[FrenchyBearpaw]

Ya -- for years I thought Pluto was our 9th planet.

It sounded reasonable & realistic to my science teacher, who graded me on it.

Part of a person's ability to survive is being able to see things for what they are (see Gonzales' book "Deep Survival: Who Lives, Who Dies, And Why").

You can classify Pluto however you want, it makes no difference to me personally, as I can accept however the IAU decides to define it. That doesn't change the fact that there is a body of rock and ice that is one of over 70K other objects making up the Kuiper belt and orbits the sun every 248yrs.

Just a tip: You may want to pick a less trivial example for whatever point it was you were tying to make.

 

[Thecure]

Yeah, Is AV joking?

 

[daviddolphin]

The end species in the ring cannot interbreed.
You would say these are the same kind and species?

 

[AV1611VET]

The end species in the ring cannot interbreed.
You would say these are the same kind and species?

Are you asking me?

 

[daviddolphin]

Surely.

 

[AV1611VET]

Surely.

Correct me if I'm wrong, please, but let's use the alphabet as a ring species.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A can mate with B but not C, correct?

And B can mate with A or C, but not D?

And C can mate with B or D, but not E?

And so on -- right?

 

[daviddolphin]

Letters are not animals. It would be better to stick to the topic at end.

I suppose your analogy is acceptable.

 

[AV1611VET]

Letters are not animals. It would be better to stick to the topic at end.

I suppose your analogy is acceptable.

Coyote → Wolf → Domestic Dog → Dingo

A coyote cannot mate with a wolf, which cannot mate with a domestic dog, which cannot mate with a dingo.

Yet, if they were a ring species, a coyote could mate with a wolf, which could mate with either a coyote or a domestic dog, which could mate with either a wolf or a dingo, which could mate with a domestic dog.

Do I have that right?

 

[daviddolphin]

Coyote → Wolf → Domestic Dog → Dingo

A coyote cannot mate with a wolf, which cannot mate with a domestic dog, which cannot mate with a dingo.

Yet, if they were a ring species, a coyote could mate with a wolf, which could mate with either a coyote or a domestic dog, which could mate with either a wolf or a dingo, which could mate with a domestic dog.

Do I have that right?

I suppose your example is possible but the ability for Wolf/Dingo or Coyote/DomDog to breed is up in the air. The point is that when the two separate populations genetics have drifting far enough apart (Dingo and Coyote), then those two branches of the evolutionary tree can no longer interbreed. The further and further, and, longer and longer they continue to be separated the more and more different the will become.

For example. Lizards developing new organs after being faced with a new diet. (Looking for the citation on this. I apologize.)

 

[Naraoia]

In case you are unaware, this is what constitutes a "ring species" Where and when does a ring start and end? Testing the ring-species hypothesis in a species complex of Australian parrots

Four criteria strictly define circumstances for an ‘ideal’ ring-species hypothesis of speciation: (i) two distinctive forms coexist today in sympatry, (ii) gene flow through a chain of populations has connected them before and since sympatry that came about through a range shift, (iii) the chain forms a complete ring, and (iv) the terminal differentiates are connected by gradual geographical variation
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Your point being? Where did he indicate that he didn't know what a ring species was?

Just to make sure I understand this correctly. If the hypothesis of common descent is true, then species that share a common ancestor will have inherited that ancestor's DNA sequence. They will have inherited mutations unique to that ancestor.

Exactly. The "mutations unique to that ancestor" part is very important, because it's that, not the mere fact of similarity, that allows us to conclude common descent. We need a particular pattern of similarities in order for common descent to be true. ("Nested hierarchy" might sound familiar)

The other big clue is the similarities or differences that have no practical significance - such as the vestigial centromere in human chromosome 2. A chromosome doesn't need two centromeres, and that one isn't functional anyway - so what other reason for its presence than chromosome fusion? And by and large, it doesn't matter whether two chromosome-sized blocks of the same genes are in one or two pieces. IIRC, most regulatory sequences are at most a few thousand bases from the genes they affect, whereas 2a (the smaller of the two chimp chromosomes in question) contains over 110 million bases. So what other reason for the difference than an evolutionary accident?

All of this, of course, assumes that the hypothetical creator designed stuff like genomes with purpose.

I find it interesting that the author of the article is assuming the chimpanzee is the closest “human relative” when he or she says, “The correspondence of chromosome 2 to two ape chromosomes. The closest human relative, the common chimpanzee has near-identical DNA sequences to human chromosome 2, but they are found in two separate chromosomes. The same is true of the more distant gorilla and orangutan.”

Incidentally, that passage is kind of wrong. There are two chimpanzee species, and they are equally closely related to humans, so singling out the common chimp as "the" closest human relative is misleading.

Correct me if I'm wrong, please, but let's use the alphabet as a ring species.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A can mate with B but not C, correct?

And B can mate with A or C, but not D?

And C can mate with B or D, but not E?

And so on -- right?

Depends on how big you want your ring to be.

You can make the ring as large as the whole alphabet. The only criteria that the letters (populations) have to fulfill are:

- the populations inside the ring must be able to breed with both of their neighbours (so yes, B must be able to mate with A and C)

- the populations at the ends of the ring must be incompatible (so A can't breed with Z)

Within the ring, B may be able to breed with D (or even Y) if given the opportunity, but they are unlikely to meet because they live in different places.

In fact, I would expect that the ability of A to interbreed with the others would decrease gradually as we go from B to C to D all the way to Z. So A and B are fully compatible, A and C can breed but their offspring aren't going to be as healthy or fertile as A and B's, and so on, until A and Z can only conceive sad sterile hybrids if they can conceive anything at all.

 

[AV1611VET]

Your point being? Where did he indicate that he didn't know what a ring species was?

Exactly. The "mutations unique to that ancestor" part is very important, because it's that, not the mere fact of similarity, that allows us to conclude common descent. We need a particular pattern of similarities in order for common descent to be true. ("Nested hierarchy" might sound familiar)

The other big clue is the similarities or differences that have no practical significance - such as the vestigial centromere in human chromosome 2. A chromosome doesn't need two centromeres, and that one isn't functional anyway - so what other reason for its presence than chromosome fusion? And by and large, it doesn't matter whether two chromosome-sized blocks of the same genes are in one or two pieces. IIRC, most regulatory sequences are at most a few thousand bases from the genes they affect, whereas 2a (the smaller of the two chimp chromosomes in question) contains over 110 million bases. So what other reason for the difference than an evolutionary accident?

All of this, of course, assumes that the hypothetical creator designed stuff like genomes with purpose.

Incidentally, that passage is kind of wrong. There are two chimpanzee species, and they are equally closely related to humans, so singling out the common chimp as "the" closest human relative is misleading.

Depends on how big you want your ring to be.

You can make the ring as large as the whole alphabet. The only criteria that the letters (populations) have to fulfill are:

- the populations inside the ring must be able to breed with both of their neighbours (so yes, B must be able to mate with A and C)

- the populations at the ends of the ring must be incompatible (so A can't breed with Z)

Within the ring, B may be able to breed with D (or even Y) if given the opportunity, but they are unlikely to meet because they live in different places.

In fact, I would expect that the ability of A to interbreed with the others would decrease gradually as we go from B to C to D all the way to Z. So A and B are fully compatible, A and C can breed but their offspring aren't going to be as healthy or fertile as A and B's, and so on, until A and Z can only conceive sad sterile hybrids if they can conceive anything at all.

Then this goes right along with what I believe -- A can breed, but will eventually hit a barrier (Z) it cannot cross.

 

[Naraoia]

I suppose your example is possible but the ability for Wolf/Dingo or Coyote/DomDog to breed is up in the air. The point is that when the two separate populations genetics have drifting far enough apart (Dingo and Coyote), then those two branches of the evolutionary tree can no longer interbreed. The further and further, and, longer and longer they continue to be separated the more and more different the will become.

For example. Lizards developing new organs after being faced with a new diet. (Looking for the citation on this. I apologize.)

I suspect the citation is Herrel et al. (2008). If that's the one you had in mind, it's not necessarily a good example. I don't think there is a reproductive barrier between the two populations, and many of their differences may not even be genetic. For example, what you feed the lizards matters more to gut structure than which population they came from. (That paper is free from here, if you are interested)

They may well become different species if left alone for long enough, but at this point, they may be little more than an impressive example of phenotypic plasticity.

 

[Naraoia]

Then this goes right along with what I believe -- A can breed, but will eventually hit a barrier (Z) it cannot cross.

Unless I completely misread you all these years, this is not your kind of barrier. Wasn't your barrier a limit to the amount of evolutionary change that can happen to something?

In this case, there's nothing to say that A won't become even more different from Z - in fact, that's just what we expect with time, precisely because they've stopped breeding with each other.

Your kind of barrier would mean that A and Z would reach a certain level of differentness (geez, is that even a word?), then stay at that level ad infinitum. (And by the "kind" concept dissected in the OP's video, they have already crossed that barrier by not being able to breed.)

 

[OllieFranz]

Then this goes right along with what I believe -- A can breed, but will eventually hit a barrier (Z) it cannot cross.

The problem is how you are defining a barrier. Yes, A and Z are incompatable and that fact is a barrier to them interbreeding. But when you say that this barrier is why common descent fails, that's where you lose us. The barrier is only between the ends of the ring. In the middle of the ring, in the environment in which the common ancestor lived, the population can freely interbreed with both its neighbors.

If something should happen to cause one of the middle populations to die out -- as has happened with the greenish warblers within recorded history -- then there is no longer a smooth and perfect transition around the ring, and the two broken pieces will only continue to develop more and more differences. Two different species will have descended from one common ancestor. If the separate populations should continue to spread (Say a colony of A moves from the territory the cohabit with Z and into Y's territory), they will either compete for the same ecological niche (which may force one or the other toward extinction), or they will adapt to separate ecological niches. If the second, then they will continue diverge and show less of their common ancestry. But that will not change the fact of that common ancestry.

 

[AV1611VET]

Two different species will have descended from one common ancestor.

I'm not going to spend too much time with this, because I don't know what I'm talking about; but it seems to me that that is what I said earlier.

A coyote (common ancestor) gives rise to a wolf (species 1), which gives rise to the domestic dog (species 2), which gives rise to the dingo (species 3).

Thus a coyote has given rise to 3 different species.

BUT -- they are all "dogs", no?

 

[SkyWriting]

Unless I completely misread you all these years, this is not your kind of barrier. Wasn't your barrier a limit to the amount of evolutionary change that can happen to something?...

It's easier to say the species are immutable than to explain that any engineered product has it's limitations.

Living organisms have design limitations for heat, drought, energy, etc.
The DNA language has built in variability so any creature can be stressed and survive. This is exactly the same for the individuals months or years as well as the population over 1000's of years.

Once you have mapped the entire DNA language and cross referenced the interactions with every function in the body and tested every environmental influence on each living variation, then mapped that over time, you'll have a reasonable idea of the limitations that a species evolves.

 

[Naraoia]

It's easier to say the species are immutable than to explain that any engineered product has it's limitations.

Living organisms have design limitations for heat, drought, energy, etc.
The DNA language has built in variability so any creature can be stressed and survive. This is exactly the same for the individuals months or years as well as the population over 1000's of years.

Uh... OK, so?

Once you have mapped the entire DNA language and cross referenced the interactions with every function in the body and tested every environmental influence on each living variation, then mapped that over time, you'll have a reasonable idea of the limitations that a species evolves.

That whole sentence is essentially a euphemism for "never".

 

[OllieFranz]

I'm not going to spend too much time with this, because I don't know what I'm talking about; but it seems to me that that is what I said earlier.

A coyote (common ancestor) gives rise to a wolf (species 1), which gives rise to the domestic dog (species 2), which gives rise to the dingo (species 3).

Thus a coyote has given rise to 3 different species.

BUT -- they are all "dogs", no?

And, going further back, a "bear-dog" species gave rise to the first bear species and the first dog species; and even earlier a not-yet-specialized carnivore species gave rise to the first "bear-dog" species and the first feline-like species (which gave rise to the felines, etc.).

So, no, they are not all dogs. Some are bears and some are cats. This is equally confirmed both in the fossil record and in the similarities and differences in the genomes.