reproductive barriers

[revolutio]

At the point where the two will not or cannot interbreed to produce viable offspring anymore. Sorry, but I didn't mean to put "inviable" species where I did. I see that I put that analogy together too hastily. The creature at the 3:00 position would be able to interbreed with the 4:00 creature, but would less and less probability of producing viable offspring with any creature after (further away) than that.

The same thing applies in anagenesis too. Homo habilis likely could have interbred with either Australopithecus africanus or with Homo erectus, but not with Ardipithecus or Neandertals. In this case, it wouldn't a geographic barrier but a chronological one.

I understand how Ring Species work.

It is. In order for two (evidnetly closely-related) populations to be considered separate species there are two criteria:
(1) they do not interbreed to produce viable offspring. (mind you, I said do not, not can not, although "cannot" also applies eventually.
(2) each population must share a consistent trait common to every member of that population, but which is not present in any member of the other population. Look at the subtle character differences between lions and tigers for example, or rock-hopper penguins vs any other penguin species.

Let me clarify my point about the ring species using these criteria.

12:00 - this species can interbreed with the species at 1:00 and 11:00 thus they are of the same species
11:00 - interbreeds with 12:00 and 10:00, thus is the same species as them. Though 10:00, 11:00, and 12:00 should be able to interbreed being of the same species, 10:00 is not compatible with 12:00.

See where I run into the problem with that definition?

 

[JohnR7]

yes everyone that goes to Harvard is an idiot. MIT on the other hand...

Opps, be careful, Dr. Gerald Schroeder earned his earned his BSc, MSc and PhD at MIT.

 

[Aron-Ra]

Like I said I dont know where you want to go with this. Pointing out that evolutionists don't agree with one another is hardly "knocking down evolution". That is how real science works. No two people agree on everything.

yes everyone that goes to Harvard is an idiot. MIT on the other hand...

Ersnt Mayr and Stephen J. Gould were both Harvard University professors, and they both had different ideas about how evolution progressed.

Mayr says that all evolution is gradual. Gould said that it was punctuated with periods of rapid diversification followed by periods of relative stasis. Actually, both were correct of course, but they still disagreed.

 

[Aron-Ra]

I understand how Ring Species work.

Let me clarify my point about the ring species using these criteria.

12:00 - this species can interbreed with the species at 1:00 and 11:00 thus they are of the same species
11:00 - interbreeds with 12:00 and 10:00, thus is the same species as them. Though 10:00, 11:00, and 12:00 should be able to interbreed being of the same species, 10:00 is not compatible with 12:00.

See where I run into the problem with that definition?

Yes. You're forgetting that 1:00 is the original parent of all of them. 12:00 is where the ring comes to a close. So 12:00 would not be able to interbreed with 1:00 or 2:00 even though it could with 11:00 and maybe with 10:00 too.

Here's the kicker. Depending on the severity of the example, either 12:00 or 1:00 might be able to interbreed with 6:00 or 7:00 even though either extreme still couldn't interbreed directly with each other.

The problem with our definitions is that 1:00 and 12:00 are genetically-isolated with the very "reproductive barriers" that JohnR7 cited earlier. So they would be considered distinctly-separate species. But what about all the others in between? They would all be considered sub-species (or demes) or 1:00. 12:00 would be a daughter species of 1:00 even though it was directly descended from 11:00, itself a subspecies of 1:00. 11:00 wouldn't get proper credit except in a phylogenetic tree. A cladogram would list 2:00 thru 11:00 equally, (under the 1:00 creature) and 12:00 would be listed in the next group.

Gosh, I don't know why some people don't understand this.

 

[Split Rock]

Actually Ernst Mayr said it, but if you want to falsify his definition of species, that is fine with me.
Do you think we should tell Harvard University they made a mistake when they named a library after him?

I warned you guys, that I was going to start to put evolutionary theory out here
and you were going to knock it down left and right and disprove it for me. Thanks

Mayr's definition of species works fairly well for animals, but works poorly for microorganisms and plants in particular. Different species of plant can sometimes interbreed and produce a new species. Different species of bacteria can exchange genetic material between each other. None of this disproves evolution, John. Populations continually evolve, and therefore no species is set in stone. Ring species are an example of this. This all makes sense in term of evolution, but makes no sense in terms of set "Kinds." It is the creationists who insist on barriers between created groups of organisms, not scientists. What Mayr was explaining to in your quote was how Speciation occurs, not that species are somehow immutable.

 

[revolutio]

Yes. You're forgetting that 1:00 is the original parent of all of them. 12:00 is where the ring comes to a close. So 12:00 would not be able to interbreed with 1:00 or 2:00 even though it could with 11:00 and maybe with 10:00 too.

Ack, when I wrote that I wasn't going by your example but just using an arbitrary starting point (top of the clock). So I wasn't assuming any of them as the original parent.

A cladogram would list 2:00 thru 11:00 equally, (under the 1:00 creature) and 12:00 would be listed in the next group.

Okay that answers my question (and makes my head spin, but that is beside the point).

One last question, wouldn't that still mean that some species were compatible with other species?

 

[Cantuar]

A while ago, the question was asked: "What is a kind". I said it is simply something that can reproduce itself. I just ran across a definition for a species and it is pretty much the same definition. Notice we are told that a species "are separated from each other by reproductive barriers".

So you're saying that "kinds" are species? Do you have any idea how many animals would need to have been on the ark in that case?

 

[Jet Black]

So you're saying that "kinds" are species? Do you have any idea how many animals would need to have been on the ark in that case?

John is just being rather wooly, don't worry about it

 

[Philosoft]

Nope, I just accept evolutions definition that a species is something with "reproductive barriers". I will allow evolutionists to argue among themselves as to how all the details work out on that one. So, when you figure it out, you let us know.

What is the problem here? A species is reproductively isolated from another species via accumulated genetic differences. Two organisms that can produce viable offspring might not be distinct species, but that doesn't mean they are genetically identical.

In any case, Mayr does have a speciation theory known as peripatric speciation. It relies heavily on geographic isolation to distribute accumulated mutations.

 

[JohnR7]

So you're saying that "kinds" are species? Do you have any idea how many animals would need to have been on the ark in that case?

Nothing is impossible for God. I believe in a local flood anyways.

 

[Philosoft]

John is just being rather wooly, don't worry about it

Well, to be fair, it is quite a mammoth undertaking.

 

[JohnR7]

What is the problem here?

I don't think there is a problem, it's just another area where science and the Bible are in agreement.
For some reason, some people get upset when scientific theorys line up with what the Bible says.

 

[Philosoft]

I don't think there is a problem, it's just another area where science and the Bible are in agreement.

Are you mad? Simply because we can observe a point at which genetic asimilarity renders reproduction nonviable does not mean those points describe Biblical archetypes.

For some reason, some people get upset when scientific theorys line up with what the Bible says.

Perhaps because the claims of such are made by people who don't have a clue.

 

[ego licet visum]

In this case that tigers and lions are the same species. A more accurate definition would be animals that can reproduce, and have children that can also reproduce. Ligers and tions are unable to reproduce.

 

[Aron-Ra]

One last question, wouldn't that still mean that some species were compatible with other species?

Yes it does. The problem is that nature doesn't always conform to our definitions. In all of taxonomy, speciation is the only place where we can draw a "clear" line. But that line really isn't that clear. On some very rare occasions, mules will be fertile, and where does that leave us?

 

[theFijian]

That is fine with me, this is just another example of where evolutionists can not agree amomg themselves.
Even to the point that you call a evolutionists definition "ambiguous".

What happens when you apply this logic to Christianity?

 

[JohnR7]

What happens when you apply this logic to Christianity?

In Heaven everyone will be of one mind and one accord. We will all be in agreement, because we will all have the mind of Christ and the thoughts of God. We will all be in agreement with each other, because we will all be in agreement with God. Even now we are all in the same family, the family of God. We have family relationships with each other, mother, father, sister, brother, daughter, son. Depending on our age and how mature we are as a christian.

 

[revolutio]

Yes it does. The problem is that nature doesn't always conform to our definitions. In all of taxonomy, speciation is the only place where we can draw a "clear" line. But that line really isn't that clear. On some very rare occasions, mules will be fertile, and where does that leave us?

Well I am glad I am not the poor sap who has to graph out that mess.
I had never heard of fertile mules I will have to look into that, that would be really interesting.

Thank you for the info.

 

[Nathan Poe]

In Heaven everyone will be of one mind and one accord. We will all be in agreement, because we will all have the mind of Christ and the thoughts of God. We will all be in agreement with each other, because we will all be in agreement with God. Even now we are all in the same family, the family of God. We have family relationships with each other, mother, father, sister, brother, daughter, son. Depending on our age and how mature we are as a christian.

And everything on Earth which made us who we are will be erased.

Sounds like brainwashing to me.

 

[JohnR7]

Sounds like brainwashing to me.

Brainwashing? Well, that is one way to get rid of dirty thoughts.

Rev. 7:14
And I said to him, "Sir, you know." So he said to me,
"These are the ones who come out of the great tribulation, and washed their robes and made them white in the blood of the Lamb.