About Evolution

[bob x]

So, I must ask again, is the human animal to be held to a different standard than the rest of nature? Is this not apologetics to attempt to overcome the logical inconsistencies surrounding the term "species?"

??????
In the rest of nature, we are concerned about barriers to interbreedability, not just about single isolated differences like skin color or whatever. There can be fuzziness about levels of difficulty in interbreeding, but when there is no difficulty whatsoever about interbreeding then there is no conceivable basis for drawing a species line.

[wil]

Darwin had written "If my theory be true, numberless intermediate
varieties… must assuredly have existed". However evolutionists, who have
been doing excavations all over the world, have been unable to uncover
even a single intermediate form.

hmmm

[Vajradhara]

Originally Posted by juantoo3

Kindest Regards, Vaj!

I am not certain I follow if this is being asked of me? For one, I have at no time espoused creationism in its raw form.

What I have asked for, consistently, is consistency in use of the term "speciation." Otherwise, I am accepting without questioning, just because it is written, just because others say so, just because it is tradition, am I not? Especially when the logic is inconsistent with the use of the terminology.

It is difficult for me to logically accept illogic application.

what is it that you want to see, Juan?

it seems like you are simply quibbling over semantics... or perhaps i'm missing your point. it's like consistency in using the term "theory". yet, i note that you have no real issue using that term, even though there are several meanings of said term.

let me ask you...

which view of gravity do you accept, the Newtonian or Einsteinian view?

the follow on is why you accept one and not the other.

metta,

~v

[juantoo3]

Kindest Regards, bobx!

Originally Posted by bob x

??????
In the rest of nature, we are concerned about barriers to interbreedability, not just about single isolated differences like skin color or whatever. There can be fuzziness about levels of difficulty in interbreeding, but when there is no difficulty whatsoever about interbreeding then there is no conceivable basis for drawing a species line.

Then please forgive my misunderstanding when one of the first examples you trotted out to someone you believed to be an illogical Christian fool was an example of skin coloration, goldfish, and not only holding it out as evidence of speciation, but claiming that it serves as an example of punctuated equilibrium. All this, when koi (grown goldfish) readily breed with their parent "species", carp. So please excuse my not understanding you here when you make this comment regarding humans. Please excuse my seeing ... an inconsistency in logic, and daring to point it out.

[juantoo3]

Kindest Regards, Vaj!

Originally Posted by Vajradhara

what is it that you want to see, Juan?

Truth.

it seems like you are simply quibbling over semantics... or perhaps i'm missing your point. it's like consistency in using the term "theory". yet, i note that you have no real issue using that term, even though there are several meanings of said term.

I am not against using the term "theory." However, I also do not use it frequently. I do believe the term is misused and abused.

However, I must ask "why the dodge?" I am certain you see, clearly, the issue I have raised. I have been slowly doing so almost since I started at CR. You of all people here, lacking perhaps only Brian, know exactly what I am at.

let me ask you...

which view of gravity do you accept, the Newtonian or Einsteinian view?

the follow on is why you accept one and not the other.

What possible bearing does this have on the subject at hand? Another dodge? Why the artful tactics of logic? Do you feel too weak to meet the challenge head on? Have I somehow struck a scientific nerve? Now you must parry and look for a weak spot to pounce upon, instead of facing the issue raised?

[bob x]

Then please forgive my misunderstanding when one of the first examples you trotted out to someone you believed to be an illogical Christian fool was an example of skin coloration, goldfish, and not only holding it out as evidence of speciation, but claiming that it serves as an example of punctuated equilibrium.

If nothing had changed but the skin color, Cyprinus aureata (goldfish) would not be reckoned a separate species from C. crassus (the "black" or "crucian" carp). There are many specialized breeds of C. aureata with different colors (including the jet-black which is a reversion to the C. crassus coloration), but none of these breeds are considered separate "species" anymore than poodles vs. chihuahuas.
When a small population is isolated, it may happen due to "founder effect" that some otherwise-rare alleles become fixed in the whole population, affecting the relative fitness of some otherwise-common genetic combinations, so that there is a rapid drift away from the old equilibrium to a new one. In this case, aside from the increased color-variability which was the original motive for segregating these fish from the others, there also followed: a change in head-shape, eliminating the barbels ("beard" fronds) found in C. crassus or C. carpio (the "common" carp); a substantial increase in the dorsal fin; and a shift in the pheromones, so that while C. crassus can interbreed with C. aureata, it doesn't like to. The barrier to interbreeding is low, which does make it ambiguous whether a "new species" should be recognized; but with time the reproductive isolation can be expected to increase, until it is the same as the barrier between either C. crassus or C. aureata on the one side and C. carpio on the other (the crassus/carpio split is likely to be rather recent).

[juantoo3]

Kindest Regards, bobx!

Originally Posted by bob x

If nothing had changed but the skin color, Cyprinus aureata (goldfish) would not be reckoned a separate species from C. crassus (the "black" or "crucian" carp). There are many specialized breeds of C. aureata with different colors (including the jet-black which is a reversion to the C. crassus coloration), but none of these breeds are considered separate "species" anymore than poodles vs. chihuahuas.
When a small population is isolated, it may happen due to "founder effect" that some otherwise-rare alleles become fixed in the whole population, affecting the relative fitness of some otherwise-common genetic combinations, so that there is a rapid drift away from the old equilibrium to a new one. In this case, aside from the increased color-variability which was the original motive for segregating these fish from the others, there also followed: a change in head-shape, eliminating the barbels ("beard" fronds) found in C. crassus or C. carpio (the "common" carp); a substantial increase in the dorsal fin; and a shift in the pheromones, so that while C. crassus can interbreed with C. aureata, it doesn't like to. The barrier to interbreeding is low, which does make it ambiguous whether a "new species" should be recognized; but with time the reproductive isolation can be expected to increase, until it is the same as the barrier between either C. crassus or C. aureata on the one side and C. carpio on the other (the crassus/carpio split is likely to be rather recent).

Thank you. Thank you very much for the clarification.

It has been some time since first we met here. Allow me to share a little about myself. I am merely a God fearing clerk with a mostly self-directed education.

Of course, we all know a God fearing clerk with a mostly self-directed education cannot possibly make a contribution that shakes the foundations of a "known" science. Right? (where's a tongue-in-cheek smiley when you need one?)

[Vajradhara]

Salaam Juan,

thank you for the post.

Originally Posted by juantoo3

Kindest Regards, Vaj!

Truth.

and how do you propose to determine this without an established intersubjective methodology? more to the point, how is "true speciation" related to the concept of "truth", with a capitol T? this seems to belie an understanding of the scientific process and how theories work and so forth.

I am not against using the term "theory." However, I also do not use it frequently. I do believe the term is misused and abused.

you, my friend, are the one that used the term "true speciation". until such time as you manage to define it, which i likened to a True Christian or a True Scotsman, then i cannot provide anything to satisfy your request.

once you do so, then i will have a chance, not saying that i can, but a chance, to provide the information which you seek.

However, I must ask "why the dodge?" I am certain you see, clearly, the issue I have raised. I have been slowly doing so almost since I started at CR. You of all people here, lacking perhaps only Brian, know exactly what I am at.

it's a moving target, Juan. define "true speciation" and i'll see what i can find to satisfy your query. however, there seems to be little value in that if you can simply say "that's not what i meant" whenever anything is presented. so, please define "true speciation" ( and i would be extra thankful if you can contrast "true" speciation from "speciation") and we can go forward.

What possible bearing does this have on the subject at hand?

it would allow me an insight into your decision making process. by which methodology have you determined which theory is correct? ipso facto, i can know what sort of information you are likely to consider as "valid".

Another dodge? Why the artful tactics of logic? Do you feel too weak to meet the challenge head on?

i do feel under the weather, if that is what your little ad hom is going for here. please, Juan, try your utmost to remain civil.

Have I somehow struck a scientific nerve? Now you must parry and look for a weak spot to pounce upon, instead of facing the issue raised?

the issue raised isn't clear, hence the asking of clarifying questions. no need to respond with such hostility, Juan. your mind reading skills do need some work, fyi.

metta,

~v

[juantoo3]

Kindest Regards, Vaj!

Thank you for the response. I am sorry to hear you are not feeling well.

Originally Posted by Vajradhara

define "true speciation" and i'll see what i can find to satisfy your query.

With all due respect old friend, you already have defined speciation, twice. #1) The proof of the pudding is that species cannot breed outside of their species (-my paraphrase, but pretty darn close to the original). #2) fallacy (if true speciation is like a true Christian, and a true Christian is a fallacy, then I must consider that in your mind true speciation is a fallacy.)

All along I have insistently held to the first definition. With the second, I don't know what to do...I do think it severely handicaps discussion though. If the goal posts are moving, it is not by my hand.

I hope you get better soon. In the meantime, I need to limit my time spent here, I have more pressing matters to attend to.

[I am free]

Originally Posted by juantoo3

With all due respect old friend, you already have defined speciation, twice. #1) The proof of the pudding is that species cannot breed outside of their species (-my paraphrase, but pretty darn close to the original).

Hi juantoo,

IMHO, a species cannot be defined as above. Even biologists would not strictly hold to such a definition.

Horses and donkeys can interbreed, so can horses and zebras. Dogs, coyotes and wolves can interbreed. Tigers and lions can too. Are these not seperate species then?

I would say a more apt definition would be that "there are barriers to interbreeding such that there is no more gene flow between the populations". The barriers could be chemical such as different pheromones, behavioural such as different mating rituals. Even mechanical. Normally an animal would recognize another animal as its own species. When it stops doing so....it could be said speciation has occurred.

I also dont think there would be an "abrupt" speciation. Wolves and dogs I believe do sometimes mate naturally (i.e. without human intervention). But over a period of time, the changes would be great enough that there would be total incapability to interbreed.

Also there would be various other things to consider such as phenotype changes, anatomical changes, changes in diet preferences, changes in behaviour, etc. before declaring that speciation has occurred.

My 2 cents.

regards.