| Belief and Spirituality General thinking beyond the boundaries of religion and organised belief |
04-13-2004, 01:07 PM
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#91 (permalink)
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God of the Mask
Join Date: Jul 2003
Location: Oregon - USA
Posts: 114
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The only flaw I see in the theory of evolution has to do with man, and just what the heck it is he's doing here? For of all the creatures on this planet he's the only one that seems incapable of living in accord mother nature. And rather than show any adaption evolutionary wise, for example a beaver develops a broad tail to swab mud, he shows a total disregard for his environment while getting nature to succumb to his every whim. Does that even sound close to living in harmony with nature? Not even the apes, our nearest relatives, are capable of perpetuating such a legacy. In fact there's nothing about them to suggest they live outside of the constraints of their environment.
So, is it possible that there's any merit to what the book of Genesis says, that man is a fallen creature which, as a consequence, puts him at odds in an environment where he doesn't belong? Whereas before the fall, he was given complete ascendency over the earth but now, he's continually at odds with it. Doesn't that sound the least bit plausible?
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04-15-2004, 05:12 AM
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#92 (permalink)
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Junior Member
Join Date: Apr 2004
Location: Ontario
Posts: 82
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Originally Posted by Iacchus
The only flaw I see in the theory of evolution has to do with man, and just what the heck it is he's doing here? For of all the creatures on this planet he's the only one that seems incapable of living in accord mother nature. And rather than show any adaption evolutionary wise, for example a beaver develops a broad tail to swab mud, he shows a total disregard for his environment while getting nature to succumb to his every whim. Does that even sound close to living in harmony with nature? Not even the apes, our nearest relatives, are capable of perpetuating such a legacy. In fact there's nothing about them to suggest they live outside of the constraints of their environment.
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Thanks for the intro to a new forum. I posted an answer there, but for the benefit of folks here, I'll post it here as well.
The flaw is not in the theory of evolution, but in one of your assumptions: that all non-human creatures live in harmony with nature. They don't necessarily. They don't so much live in harmony with nature as adapt to their environment. If the environment changes, they need to re-adapt, and often they don't. Then they become extinct. Only 1% of all known species are currently alive today. The rest failed, at some point, to live in harmony with their environment.
Humanity has achieved a level of mastery over nature that has enabled us to avoid some of the hazards of environmental change. With technology we have found ways of living in virtually every terrestrial habitat, and may one day go beyond that.
Yet in spite of that mastery, we are not totally free of natural constraints.
Five times in the history of the earth, an event has triggered a massive extinction of many species. Now a sixth is underway and the triggering event is US! Humanity and its careless exploitation of natural resources.
If we get smart enough, fast enough; if we care enough, we can stop before irreversible damage is done.
If we don't, it is entirely possible that one of the species whose extinction we ensure is our own.
Either consequence is perfectly compatible with evolution.
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04-15-2004, 12:57 PM
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#93 (permalink)
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Peace, Love and Unity
Join Date: Jul 2003
Location: Scotland
Posts: 5,413
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Thanks for posting it here.
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04-26-2004, 05:10 AM
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#94 (permalink)
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~~~~~~~~~
Join Date: Jan 2004
Location: Gator Country, FL, USA
Posts: 5,733
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Kindest Regards, gluadys!
I wanted to take a moment and let you know I am researching a response. I have gone through a lot of information, but I have a great deal more to go through yet to post a proper reply.
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Originally Posted by gluadys
The question is, given the processes used by evolution, why would you expect any other result? This goes back to understanding the branching nature of evolution. Once that is firmly in mind, this becomes a red herring question.
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This had to do with fruit flies remaining fruit flies, meaning that they are still generally capable of "interbreeding." At some point, the "evolved" species is no longer fruit fly, at which point I would be satisfied the qualification of distinct speciation would have occurred. That is the basis of my comment, which I hope resolves the red herring.
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Populations which do not inter-breed are effectively separate species.
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Granted. Isolation, for example, can cause species to adapt. Some of the material I covered demonstrated where isolated "species" were artificially reintroduced and began hybridizing. This is not "true" or possible in all instances, but there are enough "exceptions" to give pause in consideration. I do not have my research in front of me to properly quote, but one example that stood out to me was that of the wild horse mating with the domestic horse, and producing viable offspring, even though the wild horse has two more genes than the domestic.
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If you go to www.talkorigins.org and type "speciation" into their search engine, you can bring up a document called "Observed Instances of Speciation" which gives more detail on fruit fly speciation and speciation in other organisms. Part of the document called "29+ Evidences for Macro-evolution also gives details of field and labratory instances of speciation."
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I did go here, and I printed out some information, which I will go through when I can.
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Actually, as Darwin correctly observed in the first chapter of Origin of Species, if you want to get a new species, hybridization is not the best way to go about it. Mendel's work confirmed this. The first generation may be quite uniform and have all the good qualities you want to combine. But when you mate the individuals in the first generation to produce the next, genetic sorting re-aligns the characteristics so that you get a variety of results. And eventually, without careful control of the stock, it tends to revert to its wild form.
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I haven't read Darwin yet. Mental block, I'm sure. Perhaps one day. If I recall my high school biology class, Mendel was the monk who raised petunias to demonstrate genetic disposition (dominant and recessive genes). I also recall reading somewhere that he also fudged an awful lot of his data to make his point. My point being that "recessive" is not necessarily "submissive", perhaps just unexpressed individualization.
Controlled hybridization has produced many of the domesticated varieties we are familiar with. I cannot refute your comment, but selective breeding has served humanity well over the course of 4 to 5 thousand years of agriculture and animal husbandry. Left to their own devices, what you say about reversion is true. Yet, through selective breeding, as explained by the teacher in the aforementioned biology class using a mathematical model that I do not fully understand, he explained that a new "breed" could be created after something like 12 generations. Even after only 6 generations, the preferred genetic disposition was the dominant expression, provided the breeding stock was carefully selected and controlled. In effect, this is how the various breeds of dogs and cats were and are bred, as well until recently the majority of agricultural crops and livestock.
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The more effective way to get new species is through allopatric speciation. Start with one species. Divide it into groups. Put each group into a different environment. Let it remain there for several generations until it is adapted to that environment. Chances are that when you compare them with each other and with the original, you will find you now have several different species, each with its own distinct characteristics.
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Certainly. This is the mechanism used throughout nature. The example that immediately comes to mind is the blind cave fish. I don't know what stock it comes from, but the supposition is that after being trapped in a dark cave they lost the need for sight, so their eyes degenerated and now they no longer have the capacity to see. This is an adaptation, as presumably they have acquired other means to navigate (they do well enough in an aquarium). I do not know if they can mate with the parent stock.
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It is true that hybridization sometimes gives a new species, but it is a rarer occurrence.
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The example I looked at concerning a weed in England specifically pointed out a natural hybridization between two "native" or "naturalized" (related) species. Another example, controlled, crossed a radish with a cabbage (in Russia). The result was not worthwhile, producing the leaves of the radish with the root of the cabbage, but the two were distinct and unrelated species (or at the least not anywhere near closely related, radish is not in the brassica family).
While natural hybridization may not be the prevalent form, it does occur.
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Actually, the fact that they freely cross-pollinate means they are NOT separate species, but varieties of the same species, just as terriers and poodles are varieties of one canine species: the domestic dog.
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Another collection of information I looked at considered the development of the domestic dog from wild stock. After considering wolves, dingos, hyenas, coyotes and foxes, the research concluded that domestic dogs came from 4 distinct lines of the wolf, from different places in the world. The influence of the coyote and the others was dismissed by the conclusions. And the 4 lines of wolf are distinct, and at best only very distantly related. It was also concluded that fresh influx of "wild" blood from time to time came back into the domestic lineages. But, as far as I know, other than the problematics of size, all dogs are capable of interbreeding.
Actually, I think I have Vajradhara to thank for pointing me to the bulk of the information I have presented to this point.
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As the taxonomy below shows, cabbage, broccoli, kale, kohlrabi and brussel sprouts are all varieties of Brassica oleracea a species of mustard. Each has been bred by human gardeners for its particular characteristics.
Brassica oleracea
Brassica oleracea var. acephala (kale)
Brassica oleracea var. alboglabra (Chinese kale)
Brassica oleracea var. botrytis (cauliflower)
Brassica oleracea var. capitata (cabbage)
Brassica oleracea var. gemmifera (brussel sprouts)
Brassica oleracea var. gongylodes (kohlrabi)
Brassica oleracea var. italica (asparagus broccoli)
Brassica oleracea var. medullosa (marrow-stem kale)
Brassica oleracea var. oleracea
Brassica oleracea var. ramosa (perennial kale)
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You are correct, brassica is the scientific latin nomenclature. Cole is the colloquial nomenclature. I am not incorrect. Check the Old Farmer's Almanac or Organic Gardening or Mother Earth News.
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Yes, good example both of the possibility of hybridization between closely related species, and of the limitations.
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This dealt with sterility. And yes, it is a common problem with hybrids. Yet some of the research I looked at concluded that even among typically sterile offspring, it is quite common for an occasional virile offspring to occur. I concede that "occasional" is not conducive to natural selection, certainly not to abundant regeneration, but it does occur naturally. Adaptation and individualization.
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Of course, biotechnology could not even be conceived without the fact of common descent.
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All life shares genomic traits. Which is why deliberate genomic interference can occur in a laboratory setting. Which is why jellyfish can be deliberately mixed with rabbits, flounders with strawberries and tomatoes, bacillus (sp?) thurigensis with corn, and radishes with cabbages.
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For sexually reproducing species, the definition of species is related to the ability to mate and reproduce. If Alba can mate and reproduce with other rabbits of her species, then Alba is not a new species.
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That is why she is kept under wraps, to keep her from accidentally introducing the genomic manipulation into the natural system.
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Adaptation is a consequence of natural selection. Adaptation does not generally occur all at once in a single generation. It takes place through the accumulation of successive variations by natural selection. A species which has become fully adapted to its environment may have become a different species than the one that first migrated into the same environment.
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Some of the examples I looked at demonstrate this, like creatures stranded in an island environment, adapt to their surroundings (or perish, in which case we would not be discussing them). Some of them do change, very quickly, in the space of a very few generations, such as the English moths. This isn't hard to recognize when one sees the inherent differences in specific individuals. We would tend to look at moths as being moths (they all look the same to me...), but each individual has subtle differences. Like humans, short/tall, thin/stocky, fair skin/dark skin, fine hair/thick hair. Sorry for the shift in example, but I am not familiar with dissimilarities in moth populations. If a specific trait shows an advantage in survivability, that trait becomes more dominant in the gene pool of that species. Like changing color from light to dark in the case of the moths. There always were dark individuals, but they were the minority in the population prior to the industrial revolution. Against the soot that built up on everything, the light moths stood out and became better prey. The dark colored ones gained ascendency not through change per se, but through a greater percentage of dark color being able to survive in the new environment. Adaptation, but both colors were already in existence in the population, before and after the transition stage.
Another consideration occurred to me, thinking of humans. The races are quickly becoming one. A poet and frequent guest speaker on PBS, Richard Rodriguez, pointed out a few months ago what he calls "the browning of America." As we become more racially tolerant and intermingled, we are becoming more the same. Yet I thought evolution was the divergence of populations? Perhaps an isolated circumstance, but considering it directly involves humanity, it is an exception worth great consideration. (LOL, evolution meets anthropology through philosophy!)
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Adaptation, in and of itself requires a change in the distribution of gene alleles in the population. And that is the classic definition of evolution used today "A change in the distribution of alleles in a population that transcends generations."
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Yes, but that distribution is throughout the species as a whole, at least in the case of the moths. The differing alleles were already distributed, as individualizations, throughout the population, in greater and lesser quantities.
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When such changes also lead to speciation, that is unquestionably evolution.
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Then why does a fruit fly remain a fruit fly? The herring has changed color. If it became a distinct "other", it would be an evident "species," but as long as it remains a fruit fly capable of interbreeding, it is merely an adaptation. Choosing not to interbreed given choice, might lead as you indicate, at which point I could humbly concede. Even in looking at the fruit fly info, the choice not to breed with the parent stock was not the indicator, it was a differentiation or individualization that was highlighted in a specific population. In limited populations, I seem to recall a reversion to interbreeding with the non-preferred species, although I will be hard pressed to find that in the info.
The balance of the conversation dealt with crocs and turtles, and I printed that material out just today and haven't had the oppportunity to go through it with any detail. The croc line, I did read, was the predecessor to and ancestor of one of the major lines of dinosaurs, and yet managed to outlive an entire evolutionary branch? The mega-crocs died out, but the several species composing today's crocodiles, alligators and caimans, is largely unchanged since long before the dino-extinction, something like 120 million years ago. These are the creatures supposed to have made the transition from water to land, some of the original amphibians.
Thank you very much for your input. You have made me do my homework. I am still having trouble accepting the establishment doctrine concerning evolutionary theory, and there is much more that impinges on that mental outlook. Adaptation is a viable and recognized and demonstrated act of nature. Crossing the boundary from one species into another is not demonstrated to my satisfaction, at least not in the sense of not being able to interbreed.
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04-26-2004, 03:32 PM
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#95 (permalink)
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What was the question?
Join Date: Dec 2003
Location: Maryland
Posts: 9,060
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Originally Posted by juantoo3
Kindest Regards, gluadys!
I wanted to take a moment and let you know I am researching a response. I have gone through a lot of information, but I have a great deal more to go through yet to post a proper reply.
This had to do with fruit flies remaining fruit flies, meaning that they are still generally capable of "interbreeding." At some point, the "evolved" species is no longer fruit fly, at which point I would be satisfied the qualification of distinct speciation would have occurred. That is the basis of my comment, which I hope resolves the red herring.
Granted. Isolation, for example, can cause species to adapt. Some of the material I covered demonstrated where isolated "species" were artificially reintroduced and began hybridizing. This is not "true" or possible in all instances, but there are enough "exceptions" to give pause in consideration. I do not have my research in front of me to properly quote, but one example that stood out to me was that of the wild horse mating with the domestic horse, and producing viable offspring, even though the wild horse has two more genes than the domestic.
I did go here, and I printed out some information, which I will go through when I can.
I haven't read Darwin yet. Mental block, I'm sure. Perhaps one day. If I recall my high school biology class, Mendel was the monk who raised petunias to demonstrate genetic disposition (dominant and recessive genes). I also recall reading somewhere that he also fudged an awful lot of his data to make his point. My point being that "recessive" is not necessarily "submissive", perhaps just unexpressed individualization.
Controlled hybridization has produced many of the domesticated varieties we are familiar with. I cannot refute your comment, but selective breeding has served humanity well over the course of 4 to 5 thousand years of agriculture and animal husbandry. Left to their own devices, what you say about reversion is true. Yet, through selective breeding, as explained by the teacher in the aforementioned biology class using a mathematical model that I do not fully understand, he explained that a new "breed" could be created after something like 12 generations. Even after only 6 generations, the preferred genetic disposition was the dominant expression, provided the breeding stock was carefully selected and controlled. In effect, this is how the various breeds of dogs and cats were and are bred, as well until recently the majority of agricultural crops and livestock.
Certainly. This is the mechanism used throughout nature. The example that immediately comes to mind is the blind cave fish. I don't know what stock it comes from, but the supposition is that after being trapped in a dark cave they lost the need for sight, so their eyes degenerated and now they no longer have the capacity to see. This is an adaptation, as presumably they have acquired other means to navigate (they do well enough in an aquarium). I do not know if they can mate with the parent stock.
The example I looked at concerning a weed in England specifically pointed out a natural hybridization between two "native" or "naturalized" (related) species. Another example, controlled, crossed a radish with a cabbage (in Russia). The result was not worthwhile, producing the leaves of the radish with the root of the cabbage, but the two were distinct and unrelated species (or at the least not anywhere near closely related, radish is not in the brassica family).
While natural hybridization may not be the prevalent form, it does occur.
Another collection of information I looked at considered the development of the domestic dog from wild stock. After considering wolves, dingos, hyenas, coyotes and foxes, the research concluded that domestic dogs came from 4 distinct lines of the wolf, from different places in the world. The influence of the coyote and the others was dismissed by the conclusions. And the 4 lines of wolf are distinct, and at best only very distantly related. It was also concluded that fresh influx of "wild" blood from time to time came back into the domestic lineages. But, as far as I know, other than the problematics of size, all dogs are capable of interbreeding.
Actually, I think I have Vajradhara to thank for pointing me to the bulk of the information I have presented to this point.
You are correct, brassica is the scientific latin nomenclature. Cole is the colloquial nomenclature. I am not incorrect. Check the Old Farmer's Almanac or Organic Gardening or Mother Earth News.
This dealt with sterility. And yes, it is a common problem with hybrids. Yet some of the research I looked at concluded that even among typically sterile offspring, it is quite common for an occasional virile offspring to occur. I concede that "occasional" is not conducive to natural selection, certainly not to abundant regeneration, but it does occur naturally. Adaptation and individualization.
All life shares genomic traits. Which is why deliberate genomic interference can occur in a laboratory setting. Which is why jellyfish can be deliberately mixed with rabbits, flounders with strawberries and tomatoes, bacillus (sp?) thurigensis with corn, and radishes with cabbages.
That is why she is kept under wraps, to keep her from accidentally introducing the genomic manipulation into the natural system.
Some of the examples I looked at demonstrate this, like creatures stranded in an island environment, adapt to their surroundings (or perish, in which case we would not be discussing them). Some of them do change, very quickly, in the space of a very few generations, such as the English moths. This isn't hard to recognize when one sees the inherent differences in specific individuals. We would tend to look at moths as being moths (they all look the same to me...), but each individual has subtle differences. Like humans, short/tall, thin/stocky, fair skin/dark skin, fine hair/thick hair. Sorry for the shift in example, but I am not familiar with dissimilarities in moth populations. If a specific trait shows an advantage in survivability, that trait becomes more dominant in the gene pool of that species. Like changing color from light to dark in the case of the moths. There always were dark individuals, but they were the minority in the population prior to the industrial revolution. Against the soot that built up on everything, the light moths stood out and became better prey. The dark colored ones gained ascendency not through change per se, but through a greater percentage of dark color being able to survive in the new environment. Adaptation, but both colors were already in existence in the population, before and after the transition stage.
Another consideration occurred to me, thinking of humans. The races are quickly becoming one. A poet and frequent guest speaker on PBS, Richard Rodriguez, pointed out a few months ago what he calls "the browning of America." As we become more racially tolerant and intermingled, we are becoming more the same. Yet I thought evolution was the divergence of populations? Perhaps an isolated circumstance, but considering it directly involves humanity, it is an exception worth great consideration. (LOL, evolution meets anthropology through philosophy!)
Yes, but that distribution is throughout the species as a whole, at least in the case of the moths. The differing alleles were already distributed, as individualizations, throughout the population, in greater and lesser quantities.
Then why does a fruit fly remain a fruit fly? The herring has changed color. If it became a distinct "other", it would be an evident "species," but as long as it remains a fruit fly capable of interbreeding, it is merely an adaptation. Choosing not to interbreed given choice, might lead as you indicate, at which point I could humbly concede. Even in looking at the fruit fly info, the choice not to breed with the parent stock was not the indicator, it was a differentiation or individualization that was highlighted in a specific population. In limited populations, I seem to recall a reversion to interbreeding with the non-preferred species, although I will be hard pressed to find that in the info.
The balance of the conversation dealt with crocs and turtles, and I printed that material out just today and haven't had the oppportunity to go through it with any detail. The croc line, I did read, was the predecessor to and ancestor of one of the major lines of dinosaurs, and yet managed to outlive an entire evolutionary branch? The mega-crocs died out, but the several species composing today's crocodiles, alligators and caimans, is largely unchanged since long before the dino-extinction, something like 120 million years ago. These are the creatures supposed to have made the transition from water to land, some of the original amphibians.
Thank you very much for your input. You have made me do my homework. I am still having trouble accepting the establishment doctrine concerning evolutionary theory, and there is much more that impinges on that mental outlook. Adaptation is a viable and recognized and demonstrated act of nature. Crossing the boundary from one species into another is not demonstrated to my satisfaction, at least not in the sense of not being able to interbreed.
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When a Horse breeds with a donkey, the result is a Mule. Strong, smart, loyal, steadfast, mortal. The Mule cannot reproduce, Therefore its generation is the only generation. My point is that some things just cannot be, no matter how hard we wish them to be. Some things can evolve, and some things cannot. Some thing have evolved, and some things have not. Where oh where is Man in this story?
v/r
Q
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04-26-2004, 07:09 PM
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#96 (permalink)
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~~~~~~~~~
Join Date: Jan 2004
Location: Gator Country, FL, USA
Posts: 5,733
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Kindest Regards, Quahom1!
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Originally Posted by Quahom1
When a Horse breeds with a donkey, the result is a Mule. Strong, smart, loyal, steadfast, mortal. The Mule cannot reproduce, Therefore its generation is the only generation. My point is that some things just cannot be, no matter how hard we wish them to be. Some things can evolve, and some things cannot. Some thing have evolved, and some things have not. Where oh where is Man in this story?
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Yes, sterility in hybrids is sometimes an issue, as we covered in an earlier post specifically noting mules. But I also found information concerning a wild horse (with a very unfamiliar and difficult to pronounce name) that is able to interbreed with domestic horses and produce viable offspring, despite the fact that the two have a different quantity of recognized genes, 64 for horses and 66 for the wild horse. This is also demonstrated in the equine races, reaching way back in my memory, to the quagga, an extinct shaggy zebra that died out around 1900. With the events in Iraq over the last decade or so, I haven't heard what became of the research, but there had been an attempt to extract the quagga bloodline from a line of zebras kept at a zoo in Iraq. An attempt was being made to rebirth a lost species. This could only have been conceived and undertaken if it was understood that the bloodline was contained in the hybrid form amongst those animals. And that through selective breeding it could be extracted.
Moving on to livestock, what of the bovine breeds? Is a buffalo too closely related to a heiffer? They definitely spent an awful lot of time isolated from each other in different ecologies, yet beefalo is a hybrid (in fairness, I don't know what breed buffalo are crossed with; but like dogs, bovines are pretty much interbreedable in my understanding). Or brangus, the brahma/angus cross. Scientific speculation is a wonderful tool for conceptual purposes, thinking out how things might work, then reality must set in. There are some real world examples that seriously challenge many of the notions that are espoused in the classroom as inescapable fact.
"Demonstrating that a population is reproductively isolated (in a nontrivial way) from populations that it was formerly able to interbreed with shows that speciation has occurred. In practice, it is also necessary to show that at least one isolating mechanism with a hereditary basis is present. After all, just because a pair of critters don't breed during an experiment doesn't mean they can't breed or even that they won't breed. Debates about whether a speciation event has occurred often turn on whether isolating mechanisms have been produced." -Observed Instances of Speciation, by Joseph Boxhorn, Copyright © 1993-2004, (emphasis mine)
As for "Some things can evolve, and some things cannot. Some thing have evolved, and some things have not. Where oh where is Man in this story?", man has an intimate part to play in this puzzle. Humans have been artificially selecting breeding stock for millenium, for the purpose of producing better quality and quantity of foodstuffs, livestock, draft animals and companion animals. A great deal of this has been through hybridization that has been viable.
Another take on your question is semantical. What is considered a "species" to one, seems to be equally considered too closely related by another, relegated to the status (loosely) of breed or variety. A breed is not necessarily a species, I am learning. Yet, when a fruit fly breed is held out as a species, by some of the same people who claim breeding incompatibilty as a prerequisite for speciation, I am confused over the semantic conundrum. When a chihuahua chooses not to mate with a great dane, are they then different species, or breeds?
This can even be carried a step further yet. What then, of humans? If the bonobo is so closely related to humans, having spent as much effort in evolution, why are they so undeveloped in comparison to ourselves? Why have they no speech? No fire? No sharpened implements? No stone tools? Why are they not walking out of the jungle to take better control of their world? What a difference 3-5% of the genomic string makes!
I can't find the direct quote just now, but Francis Collins has said (paraphrased), "There is only a difference of a few hundred genes between a mouse and a man. But you cannot replace those genes in a mouse and expect it to begin playing golf or listening to Mozart." The point being, there is a great deal of focus on genomic quantity of apparent matches, with little to no real attention being made ( yet!) to the quality of the apparent matches. I suspect this is because a lot of the tools for doing so do not exist.
One could extend the bonobo concept to Neandertal, who many believe to have excelled Cro-magnon in brain size and physical stature and strength. Yet, Neandertal died out, and Cro-magnon ascended. It is now believed the two were supposedly different species with common ancestry, yet they exhibited compatibility with each other. There are finds that demonstrate social interaction between them. How far this cooperation extended is still open to question, but for this discussion were they able to interbreed? If so, then they were not individual species? If not, did Neandertal keep our relatives as pets (like we might a monkey or dog)? There are some serious issues that can develop on this subject, that can affect and influence our outlook on life, society, religion, psychology and a whole gamut of other matters that affect us all at the core of our being.
In this, religion may be a gross oversimplification (according to some), but I view it as a very necessary one, without which we would never have grown past the animal stage. I am of the opinion that that "revelation" came to humanity in a moment, it was handed directly to us with purposeful intent.
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04-27-2004, 06:54 AM
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#97 (permalink)
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Junior Member
Join Date: Apr 2004
Location: Ontario
Posts: 82
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Originally Posted by juantoo3
Kindest Regards, gluadys!
I wanted to take a moment and let you know I am researching a response. I have gone through a lot of information, but I have a great deal more to go through yet to post a proper reply.
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I can't tell you what a pleasure it is to meet someone who is acutally willing to do research!!
So often those who raise questions on evolution merely rant and run.
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This had to do with fruit flies remaining fruit flies, meaning that they are still generally capable of "interbreeding." At some point, the "evolved" species is no longer fruit fly, at which point I would be satisfied the qualification of distinct speciation would have occurred. That is the basis of my comment, which I hope resolves the red herring.
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What we are really dealing with here is the imprecision of common names. More often than not common names refer to higher taxonomic orders that species.
Consider this list: platypus human rhinoceros, rabbit, beaver, armadillo, spider, frog, bat, worm.
Of these, only the platypus and the human are a single species (and then only if you count living species). There are three species of rhinoceros. The common name then refers to a genus. Rabbit, beaver and armadillo refer to all the species in their respective families. (There are at least 7 different genera of armadillo). Spider, frog and bat each refer to thousands of species in the same order. And worm is a name applied to species in several different phyla. Some worms are more closely related to spiders than to other worms. Some are more closely related to us than to other worms.
"fruit fly" refers to any of 3000 different species in the Drosophilidae family. So just because they are called "fruit flies" or "rabbits" or "frogs" does NOT mean they are capable of interbreeding.
And asking for a new species of fruit fly not to be a fruit fly is asking for a level of saltation not found in nature, for you are asking for much more than a species change. You are asking that the new species be not even of the same genus or family as its parent species.
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If I recall my high school biology class, Mendel was the monk who raised petunias to demonstrate genetic disposition (dominant and recessive genes). I also recall reading somewhere that he also fudged an awful lot of his data to make his point. My point being that "recessive" is not necessarily "submissive", perhaps just unexpressed individualization.
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No question but the examples in a high school text are very basic and simple. In real life genetics is much more complex.
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Yet, through selective breeding, as explained by the teacher in the aforementioned biology class using a mathematical model that I do not fully understand, he explained that a new "breed" could be created after something like 12 generations. Even after only 6 generations, the preferred genetic disposition was the dominant expression, provided the breeding stock was carefully selected and controlled. In effect, this is how the various breeds of dogs and cats were and are bred, as well until recently the majority of agricultural crops and livestock.
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Right. What the breeder does is control the selection process and maximize the selection pressure toward the preferred characters. It can be a very rapid process indeed. One of the things that Gould and Eldredge did was to show that quite rapid evolution is also found in nature. They called spates of rapid evolution "punctuations".
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Another consideration occurred to me, thinking of humans. The races are quickly becoming one. A poet and frequent guest speaker on PBS, Richard Rodriguez, pointed out a few months ago what he calls "the browning of America." As we become more racially tolerant and intermingled, we are becoming more the same. Yet I thought evolution was the divergence of populations? Perhaps an isolated circumstance, but considering it directly involves humanity, it is an exception worth great consideration. (LOL, evolution meets anthropology through philosophy!)
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Strictly speaking, evolution is simply an inherited genetic change in the distribution of characteristics in a population. So the changes in the distribution of melanin producing skin cells due to greater racial mixing is evolution.
If we were to apply the strict racial separation that the supporters of apartheid tried to in South Africa we would no doubt get greater racial diversity instead of homogenization. But as long as all human races live in and adapt to a wide variety of habitats, it is not likely we would get separate species. To get a distinct human species in the future it would probably be necessary to isolate a group of colonists on another planet. That would provide a distinct environment they would have to adapt to.
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Then why does a fruit fly remain a fruit fly? The herring has changed color. If it became a distinct "other", it would be an evident "species," but as long as it remains a fruit fly capable of interbreeding, it is merely an adaptation. Choosing not to interbreed given choice, might lead as you indicate, at which point I could humbly concede. Even in looking at the fruit fly info, the choice not to breed with the parent stock was not the indicator, it was a differentiation or individualization that was highlighted in a specific population. In limited populations, I seem to recall a reversion to interbreeding with the non-preferred species, although I will be hard pressed to find that in the info.
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Keep up the research. Remember it is not appearance which determines whether or not individuals are of the same species, but ability and willingness to mate and reproduce. Sexual selection (willingness to mate) is an important factor in establishing new species.
Sometimes a change in appearance initiates sexual selection and isolated breeding groups. In other cases the isolation occurs first and changes in appearance occur later. So the key is not what the populations look like or what they are called, but what they do. Do they interbreed or not?
There are several instances in which the evidence is quite conclusive that new fruit fly species (i.e. groups which no longer breed with the parent stock) have been established. Here are two:
Insects that live on a single host plant provide a model for sympatric speciation. If a group of insects switched host plants they would not breed with other members of their species still living on their former host plant. The two subpopulations could diverge and speciate. Agricultural records show that a strain of the apple maggot fly Rhagolettis pomenella began infesting apples in the 1860's. Formerly it had only infested hawthorn fruit. Feder, Chilcote and Bush have shown that two races of Rhagolettis pomenella have become behaviorally isolated. Allele frequencies at six loci (aconitase 2, malic enzyme, mannose phosphate isomerase, aspartate amino-transferase, NADH-diaphorase-2, and beta-hydroxy acid dehydrogenase) are diverging. Significant amounts of linkage disequilibrium have been found at these loci, indicating that they may all be hitchhiking on some allele under selection. Some biologists call sympatric speciation microallopatric speciation to emphasize that the subpopulations are still physically separate at an ecological level.
http://www.talkorigins.org/faqs/faq-...o-biology.html
Fruit flies do not remain the same species of fruit flies. Drosophila melanogaster populations evolved reproductive isolation as a result of contrasting microenvironments within a canyon [Korol et al. 2000]. We would not expect to see much greater divergence in historical times.
References:
Korol, A. et al., 2000. Proceedings of the National Academy of Science USA 97: 12637-12642. See also Schneider, C. J., 2000. Natural selection and speciation. Proceedings of the National Academy of Science USA 97.
http://www.talkorigins.org/indexcc/CB/CB910_1.html
Complete article
http://www.pnas.org/cgi/content/full/97/23/12637
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The balance of the conversation dealt with crocs and turtles, and I printed that material out just today and haven't had the oppportunity to go through it with any detail. The croc line, I did read, was the predecessor to and ancestor of one of the major lines of dinosaurs, and yet managed to outlive an entire evolutionary branch?
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That's correct. And the dinosaurs were a very successful branch---several sub-orders and a total span of 160 million years.
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The mega-crocs died out, but the several species composing today's crocodiles, alligators and caimans, is largely unchanged since long before the dino-extinction, something like 120 million years ago.
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Unchanged in what way? Certainly they are still part of the same reptilian order. But are they still the same species? Or even the same genus? Do they still have exactly the same characterisitics in all respects? I expect that if you check into crocodile history in more detail you will find there are significant differences between Mesozoic and modern species in the crocodilian order.
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These are the creatures supposed to have made the transition from water to land, some of the original amphibians.
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Well you certainly need to do some homework in basic taxonomy!!. Crocodiles are reptiles, not amphibians. (Crocodiles, though they spend much time in water have to come to land to lay their eggs. By contrast, even amphibians which spend most of their time on land need water, or at least a damp place, in which to lay their eggs as their young are born as tadpoles. Crocodiles lay an amniotic egg enclosed in a shell. Amphibians lay a jelly-covered egg, much like those of a fish.)
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Thank you very much for your input. You have made me do my homework. I am still having trouble accepting the establishment doctrine concerning evolutionary theory, and there is much more that impinges on that mental outlook.
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There is no doctrine of evolution as evolution is not a religious outlook. There is a theory of evolution which has a great deal of evidential support. It does help a lot to be clear as to what exactly the theory does and does not say, and I appreciate that can be difficult as the religious zeal to attack the theory has led to a great deal of mis-information being widely available.
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Adaptation is a viable and recognized and demonstrated act of nature. Crossing the boundary from one species into another is not demonstrated to my satisfaction, at least not in the sense of not being able to interbreed.
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Precisely what do you mean by "crossing the boundary from one species to another"? If there are two existing species reproducing separately, you will not find a parent in one group producing offspring that belong to the other group. Never. The best you could get is a hybrid of the two. And there are documented cases in which such a hybrid has proved fertile and become established as a third species which does not interbreed with either of its parent species.
Such hybridization is one way to get a new species, but I would call that crossing from one species to another.
The other way to get a new species that we have discussed is through population isolation. A single species is split into two species. This has also been documented both by experiment and in nature. And I don't think that can be called crossing the boundary either. It is more in the nature of erecting a boundary where there was none before.
The other way for a species to change is by phyletic gradualism. This is a gradual accumulation of changes in one species such that the species at the end of the transformative process is different from the initial stock. When phyletic gradualism occurs over time, it has to be inferred from the morphology of fossil sequences as one cannot directly test whether the newer species could or could not interbreed with the ancestral species. But we also see examples of phyletic gradualism in which all the gradations from one species to another are contemporaneous. Such sequences are called "ring species".
"The Arctic Ocean polar ice cap limits the species range of Sea Gulls to its periphery. Races from Siberia freely interbreed with races from America. Races from America freely interbreed with races from Europe. Going the other way, Races from Siberia freely interbreed with races from the Caucauses. However, Western European herring gull ( Larus argentatus) do not interbreed with the lesser black-backed gull ( Larus fuscus) from Centrial Europe where these races of Sea Gulls occur together in northern Europe. So, all along the ring that circumnavigates the globe about the Arctic there is gene flow but where the two ends of the ring meet in Europe there is no gene flow."
http://geowords.com/histbooknetscape/f26.htm
This is the closest example I can find of "crossing the boundary from one species to another" yet that description doesn't really seem to fit here either.
I don't know of any other way that new species evolve, so perhaps you are barking at a bogeyman that doesn't really exist in nature.
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04-27-2004, 07:01 AM
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#98 (permalink)
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Junior Member
Join Date: Apr 2004
Location: Ontario
Posts: 82
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Originally Posted by Quahom1
When a Horse breeds with a donkey, the result is a Mule. Strong, smart, loyal, steadfast, mortal. The Mule cannot reproduce, Therefore its generation is the only generation. My point is that some things just cannot be, no matter how hard we wish them to be. Some things can evolve, and some things cannot. Some thing have evolved, and some things have not. Where oh where is Man in this story?
v/r
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When things cannot evolve in response to a new environmental challenge they become extinct.
So long as a species is not extinct yet, it CAN evolve. That doesn't necessarily mean it WILL evolve. There is no living species on earth today which has not evolved. That includes humanity.
By the way what is Man? Why the upper-case letter?
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04-27-2004, 07:35 AM
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#99 (permalink)
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Junior Member
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Location: Ontario
Posts: 82
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Originally Posted by juantoo3
There are some real world examples that seriously challenge many of the notions that are espoused in the classroom as inescapable fact.
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What examples do you have in mind here juantoo?
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When a chihuahua chooses not to mate with a great dane, are they then different species, or breeds?
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It is very important to remember that evolution relates to species i.e. to populations, not to individuals. So we need to break down your question into more than one question.
1. If my pet chihuahua chooses not to mate with my neighbour's great dane, are they different species? Not necessarily. My pet chihuahua may just be finicky.
2. If chihuahuas in general choose not to mate with great danes in general, are they different species? Possibly. If they were the only breeds of dog in existence we could predict that this sexual preference on the part of chihuahuas would lead to them becoming separate species if they are not already.
3. If chihuahuas are physically incapable of mating with great danes (and I believe they are), are they different species? They certainly would be if they were the only two breeds of dog.
What prevents us from calling chihuahuas and great danes different species is the existence of other breeds of dogs, some of which can breed with chihuahuas, and some of which can breed with great danes, and which also breed with each other. So even if chihuahuas and great danes cannot interbreed directly, there is still an avenue of gene flow from one population to another via the intermediate breeds. This situation is analogous to a ring species, though I don't know that biologists would apply that term to dogs.
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This can even be carried a step further yet. What then, of humans? If the bonobo is so closely related to humans, having spent as much effort in evolution, why are they so undeveloped in comparison to ourselves? Why have they no speech? No fire? No sharpened implements? No stone tools? Why are they not walking out of the jungle to take better control of their world?
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Remember, evolution is not an assembly line which is carrying all species in the same direction. Humanity is not a model which other species are trying to emulate, nor a goal they are striving to reach.
Bonobos don't speak because the position of their larynx is different from that in humans. This makes the pharyngeal area less flexible and unsuited for the fine-tuned production of sounds needed for speech.
They are capable of understanding speech and learning sign language or other substitutes for speech.
They do make and use tools, but do so on an ad hoc basis. They appear not have the intellectual capacity to plan tool use long in advance of need to use a tool.
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One could extend the bonobo concept to Neandertal, who many believe to have excelled Cro-magnon in brain size and physical stature and strength. Yet, Neandertal died out, and Cro-magnon ascended.
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Cro-Magnon did not "ascend". Cro-Magon is an early homo sapiens culture which appeared in Europe about 25,000 to 30,000 years ago. Cro-Magnons are no more different from you and I than Germans or Brazilians. Not a different species at all. Just a different culture, like Egyptian or Babylonian.
And, more to the point. Evolution should never be thought of as "ascension". Evolution is not a process of ascending a ladder. It is a process of radiation into different ecological niches. No one ecological habitat makes a species more "ascended" or "evolved" than another.
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It is now believed the two were supposedly different species with common ancestry, yet they exhibited compatibility with each other. There are finds that demonstrate social interaction between them. How far this cooperation extended is still open to question, but for this discussion were they able to interbreed?
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Whether they were able to or not, the latest information suggests that they did not. This may lead to reclassifying neanderthals as a separate species rather than sub-species.
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If so, then they were not individual species? If not, did Neandertal keep our relatives as pets (like we might a monkey or dog)? There are some serious issues that can develop on this subject, that can affect and influence our outlook on life, society, religion, psychology and a whole gamut of other matters that affect us all at the core of our being.
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There is no question that the neanderthals had a cultural and spiritual life, given the artifacts found with them, including their burial practices. But they did not develop the artistic expression of even the earliest known sapiens such as the Cro-magnon. They left us, for example, no cave paintings or artistically decorated tools.
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04-27-2004, 07:57 AM
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#100 (permalink)
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Join Date: Jan 2004
Location: Gator Country, FL, USA
Posts: 5,733
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Kindest Regards, gluadys!
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What we are really dealing with here is the imprecision of common names. More often than not common names refer to higher taxonomic orders that species.
Consider this list: platypus human rhinoceros, rabbit, beaver, armadillo, spider, frog, bat, worm.
Of these, only the platypus and the human are a single species (and then only if you count living species). There are three species of rhinoceros. The common name then refers to a genus. Rabbit, beaver and armadillo refer to all the species in their respective families. (There are at least 7 different genera of armadillo). Spider, frog and bat each refer to thousands of species in the same order. And worm is a name applied to species in several different phyla. Some worms are more closely related to spiders than to other worms. Some are more closely related to us than to other worms.
"fruit fly" refers to any of 3000 different species in the Drosophilidae family. So just because they are called "fruit flies" or "rabbits" or "frogs" does NOT mean they are capable of interbreeding.
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AH, thank you! Now I see a bit of light! I think I understand a little better the distinctions now. Please bear with me as I integrate this new understanding (I am liable to slip and revert to familiar understanding).
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And asking for a new species of fruit fly not to be a fruit fly is asking for a level of saltation not found in nature, for you are asking for much more than a species change. You are asking that the new species be not even of the same genus or family as its parent species.
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Now I think I better understand the red herring comment. Yes, I would expect a new species of fruit fly to remain in the fruit fly order, I would not expect it to become, say, a lizard. I am not finished with the material, and it may take a little while (I printed out probably 500 or so pages of information), but in some of the material I did go through, "different" fruit flies were able to interbreed. At least, that is what I understood the material to have said.
I will have to address the rest another time. It is way late, and I'm muddling on mentally. G'nite! and thanks for the reply!
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04-27-2004, 08:17 AM
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#101 (permalink)
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Location: Gator Country, FL, USA
Posts: 5,733
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Originally Posted by juantoo3
There are some real world examples that seriously challenge many of the notions that are espoused in the classroom as inescapable fact.-juantoo
What examples do you have in mind here juantoo?
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Quickly, before I go, I thought I had mentioned several. The two species of horse mixing, the beefalo, the brangus, the quagga/zebra. Of these examples, the brangus possibly could be argued as directly related "breeds", but as far as I know, the others constitute distinct species, that are still capable of hybrid reproduction (excepting the quagga, acting as it were posthumously).
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04-27-2004, 02:31 PM
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#102 (permalink)
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Mod ~ Eastern Thought
Join Date: Jul 2003
Location: In the jungles of Maryland being trained as a Ninja by Christopher Walken
Posts: 3,100
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a little humor to lighten the discussion..
Namaste all..
so.. i was watching Saturday Night Live, a weekly comedy show here in the States... they do a bit each week on topical news items..
so.. in the state of Georgia, recently, there was a big debate about taking the word "evolution" out of the biology classes. finally, the debate was settled and they let the word "evolution" still be used in biology, however, as a concession dinosaurs will now be called "Jesus Horses."
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04-27-2004, 03:54 PM
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#103 (permalink)
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Join Date: Jan 2004
Location: Gator Country, FL, USA
Posts: 5,733
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Originally Posted by Vajradhara
Namaste all..
so.. i was watching Saturday Night Live, a weekly comedy show here in the States... they do a bit each week on topical news items..
so.. in the state of Georgia, recently, there was a big debate about taking the word "evolution" out of the biology classes. finally, the debate was settled and they let the word "evolution" still be used in biology, however, as a concession dinosaurs will now be called "Jesus Horses."

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Cute!
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04-28-2004, 12:29 AM
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#104 (permalink)
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Join Date: Jan 2004
Location: Gator Country, FL, USA
Posts: 5,733
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Kindest Regards, gluadys!
Oh my! Where to begin. So much information to cover, while attempting to keep it in an understandable format, and retaining a friendly and open conversation.
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I can't tell you what a pleasure it is to meet someone who is acutally willing to do research!!
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I will take this as a complement. I have been a self-directed student all of my adult life. The trouble is, so much of what I came across is lost in my memory as to where it came from or who to credit. And I can accept that in the process of relying on memory, sometimes I lose the details, but I would like to believe I still retain the gist.
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So often those who raise questions on evolution merely rant and run.
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Perhaps it would be well to state that I have no hidden agenda. The axe I grind on this is my own. It is a study I have put the better part of 20 years into. I understand the frustration with adamant creationism, I do not hold that specific view, but there are components that do hold merit.
I think the best way to format this for better comprehension is to break it down into segments, because some of the same issues keep repeating themselves. Once we can resolve these, perhaps we can move on. By resolve, I do not necessarily mean convince. We can agree to disagree, and still remain friends. We need to find a way to speak to each other so that we can communicate specific ideas, with the sender and receiver each seeing the same thing. Then we will have accomplished something. At this point, the old stereotype of a plain white bread stuffed-shirt in a lab coat doing their best to talk over the head of their audience is that that is prevailing in my mind. I want to believe that is not the case. Just as I am sure certain stereotypical images are superimposed in your mind about my presentation, and gauging by some of your responses, I can assure you they are not accurate.
SEMANTICS:
I suspect there is a great deal of miscommunication between us, based in semantics and preconceptions. I am not familiar with the lingo and jargon of the biologist, and certainly not with the subtleties, innuendoes and exceptions. And I suspect you are understanding me in terms used by people who have even less clue than myself on the subject, the kind who do indeed "rant and run." I am prone to poetic license in my writing style, perhaps that is not conducive to explicit understanding. I am also not unlearned, merely predominantly self-taught. While I may hold no degree in these specific disciplines, I have had an ongoing amateur fascination with theology, anthropology, history and the natural sciences for a long time now. A jack of all trades, so to speak, I have not mastered any of them, and likely never will. Consequently the specific jargon of any one of them is largely meaningless to me in the confusion created by the sum total. Please bear with my ignorance. 
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If there are two existing species reproducing separately, you will not find a parent in one group producing offspring that belong to the other group. Never.
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Agreed, I never intended my words to be taken to imply such a ludicrous thing. That would be anti-natural, and against the cosmic order. It would be against the flow of the Tao. It would conflict with the universal IS.
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The best you could get is a hybrid of the two. And there are documented cases in which such a hybrid has proved fertile and become established as a third species which does not interbreed with either of its parent species. Such hybridization is one way to get a new species, but I would call that crossing from one species to another.
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Yes!, this is specifically that to which I was implying!
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Well you certainly need to do some homework in basic taxonomy!!. Crocodiles are reptiles, not amphibians. (Crocodiles, though they spend much time in water have to come to land to lay their eggs. By contrast, even amphibians which spend most of their time on land need water, or at least a damp place, in which to lay their eggs as their young are born as tadpoles. Crocodiles lay an amniotic egg enclosed in a shell. Amphibians lay a jelly-covered egg, much like those of a fish.)
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I thought something here didn't quite ring true with what I was taught, but since my focus was elsewhere it slipped through. My apologies.
Having skimmed quickly through some of my material, I see that early crocs are indeed considered reptiles. Some seem to consider them to be the predecessor of land reptiles, others consider them to be a transitional creature preceding both land and aquatic reptiles, and one even claims they lean towards the avian branch.
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Remember, evolution is not an assembly line which is carrying all species in the same direction. Humanity is not a model which other species are trying to emulate, nor a goal they are striving to reach.
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Very well, point taken. While humanity may not be a goal to reach or worthy of emulation, it does speak volumes in my mind as to the deliberate distinction that separates humanity from the rest of the natural order. That we are able to consider this matter in the depth and detail we collectively do, is a distinction that is worthy of note. Conscious thought is a distinction that cannot be lightly dismissed.
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Evolution should never be thought of as "ascension". Evolution is not a process of ascending a ladder. It is a process of radiation into different ecological niches. No one ecological habitat makes a species more "ascended" or "evolved" than another.
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I suspect we are saying the same thing with different words. I am trying my best to understand your preferred usage of words, it would be helpful if you met me halfway instead of relying on political correctness. If a degree is a recognition of learning, then a learned person should be able to understand and accommodate. In trying to reach you in your language, I am not speaking up to you, I am reaching out to you. Reciprocity is appreciated. Since I have no academic authority to answer to in these matters, academic authority holds no sway over my assessment of these matters. That is one of the benefits of being a free-lance thinker.
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It does help a lot to be clear as to what exactly the theory does and does not say, and I appreciate that can be difficult as the religious zeal to attack the theory has led to a great deal of mis-information being widely available.
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Agreed, but I want to be certain you understand that sword cuts both ways.
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SPECIATION:
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In real life genetics is much more complex.
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Ah, now to more of the good stuff!
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What the breeder does is control the selection process and maximize the selection pressure toward the preferred characters. It can be a very rapid process indeed. One of the things that Gould and Eldredge did was to show that quite rapid evolution is also found in nature. They called spates of rapid evolution "punctuations".
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Ah yes! Punctuated equilibrium. I am not familiar with Eldredge, but I have read a few articles by Gould. I have "Rocks of Ages" here now, but with threads like this and school besides, I haven't found the time yet to read it.
My take on punctuated equilibrium allows for "outside interference." I suppose the concept is similar, but from different vantages. That is, Gould attempts to explain the instance, I attempt to understand the underlying cause (the "Prime Mover"). Gould envisions the material aspects, I envision the spiritual aspects. In the context of this discussion, spiritual can be equated with subatomic. In other words, natural science traditionally dismisses the spiritual context, but that does not mean it doesn't exist. I accept spirit does exist, increasingly borne out by sub-atomic quantum theory, and it is towards this end that I am ultimately directing my interests. These matters are not easily transposed, and do require some conjecture. But then, doesn't most science?
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Strictly speaking, evolution is simply an inherited genetic change in the distribution of characteristics in a population. So the changes in the distribution of melanin producing skin cells due to greater racial mixing is evolution.
If we were to apply the strict racial separation that the supporters of apartheid tried to in South Africa we would no doubt get greater racial diversity instead of homogenization. But as long as all human races live in and adapt to a wide variety of habitats, it is not likely we would get separate species. To get a distinct human species in the future it would probably be necessary to isolate a group of colonists on another planet. That would provide a distinct environment they would have to adapt to.
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Disregarding the political components, am I to understand then that the human branch separated into twigs, only to be reforming into a branch? Or maybe the more appropriate nomenclature would be humans have evolved only to devolve?
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Bonobos don't speak because the position of their larynx is different from that in humans. This makes the pharyngeal area less flexible and unsuited for the fine-tuned production of sounds needed for speech.
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OK, so this is yet another to add to the list of dissimilarities between our "closest cousin" and us.
What a difference those few genes make...
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They are capable of understanding speech and learning sign language or other substitutes for speech.
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Dogs, parrots and porpoises can understand human speech too. B.F. Skinner taught rats and chickens to understand symbolic substitutes for speech. I read some material about Dr. Savage-Rumbaugh at Georgia State and Kanzi, and I am also familiar a little more so with Dr. Patterson and Koko the gorilla. Parrots and porpoises have also been trained to communicate with humans. I do find one component in these studies to be unsettling, that the scientists find it necessary to make the creatures talk up to them, rather than the humans learning to speak to the animals. In other words, why haven't the researchers invested more time in learning the animal language? It makes me wonder where the real intelligence lies in these interactions. It is not inaccurate to imply that these animals are trained and kept, much like circus animals, dependent on the ability to perform. I do not feel they are being mistreated, but the analogy is there just the same.
Perhaps this comes across somewhat jaded, for that I apologize. The creatures are wonderful, gorgeous animals, all of them. But communication is not necessarily speech, and most certainly not language. Besides a larynx, language also requires conscious rational thought. And all of these animal examples demonstrate a mental aptitude approximately equal to a three or four year old human, "here-and-now", with some concept of past (memory/remembrance), and little to no concept of future, certainly not beyond a few minutes. Which helps explain...
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They do make and use tools, but do so on an ad hoc basis. They appear not have the intellectual capacity to plan tool use long in advance of need to use a tool.
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The bonobo material I covered illustrated the use of a stick to poke a termite mound. That is barely tool usage, and hardly an indication of tool manufacture. The stick is not made pointed by deliberate means. It is not fire hardened (no fire...). It is not attached to a chipped stone. Again, these things require rational thought, and rational thought is a major component that separates humanity from the rest of the natural order. My original point was that with a 40,000-200,000 year (depending on the source of research) head start in tool manufacture for humans, one would think that our closest relative would have made some form of progress is this area by now.
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Cro-Magnon did not "ascend". Cro-Magon is an early homo sapiens culture which appeared in Europe about 25,000 to 30,000 years ago. Cro-Magnons are no more different from you and I than Germans or Brazilians. Not a different species at all. Just a different culture, like Egyptian or Babylonian.
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Very well, another thing I was taught in grade school that turns out to be incorrect. While I understood the little poster demonstrating the "radiation" of humans from the little one to the big one was rendered invalid by a number of things (such as Piltdown man and Peking man, as well the recent info concerning Neandertal), I had still been under the impression that Cro-magnon was a stage or step just prior to modern man. So, the dogma shifts again, and nobody informed me. OK...
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04-28-2004, 12:30 AM
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#105 (permalink)
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Join Date: Jan 2004
Location: Gator Country, FL, USA
Posts: 5,733
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split post, sorry!
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There is no question that the neanderthals had a cultural and spiritual life, given the artifacts found with them, including their burial practices. But they did not develop the artistic expression of even the earliest known sapiens such as the Cro-magnon. They left us, for example, no cave paintings or artistically decorated tools.
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"Oldest cave paintings ever found light up human history
Philip Willan in Rome
Thursday October 19, 2000
The Guardian
Italians were distinguishing themselves as artists long before the Renaissance and medieval times, it seems.
Researchers have found images painted some 35,000 years ago - almost certainly the world's oldest cave paintings and possibly man's first artistic creations - in a hill near the north-eastern Italian city of Verona.
The images, presented at a press conference in the city yesterday, were painted in red ochre on rock and represent an animal with an elongated neck (possibly a weasel), a mysterious five-legged animal and a man - thought to be a wizard - wearing a mask with horns. They were found last year on fragments of rock from the walls of the Fumane Cave in the Lessini Hills, north of Verona.
"They are probably the oldest cave paintings, although we cannot affirm that with scientific certainty," said Professor Alberto Broglio, who teaches palaeontology at the university of Ferrara and coordinated the excavation.
The paintings, which could at first have been mistaken for smudges of dirt, may not have the visual impact of the bull daubed on a cave wall at Lascaux in southern France or the deer of the Altamira Cave in Spain, but they are at least 10,000 years older.
Dr Alessandra Astes, director of the Natural History Museum in Verona, said scientists were able to date the paintings, which measure between one and two feet long, through carbon dating and archaeological stratographic techniques, because the rocks had become detached from the cave wall and were buried under later generations of debris.
The figure of the man in the horned mask and with his arms outstretched was extremely rare in early cave paintings, said Dr Astes.
"The find is of enormous scientific significance, which goes far beyond its artistic or stylistic value," she said.
"The find is of exceptional value. I have been working as an archaeologist for 30 years and I have no hesitation in saying that."
Dr Astes believes the images are almost certainly the oldest in Europe and, therefore, in the world.
"No art forms of similar antiquity have been found in Africa, which is, after all, the cradle of humanity," Dr Astes said.
For researchers, who are still excavating the Fumane Cave, the discovery is a crucial link in the history of human life on Earth as well as a first glimpse of the creative instinct that inspired Leonardo da Vinci and Michelangelo in a later age.
The cave contains traces of Neanderthal man and evidence of habitation by modern Homo sapiens, including sharpened flints, bones and decorations made from sea shells. There are also the remains of a prehistoric hut.
The fragments were originally covered with stalagmites which, Prof Broglio said, helped preserve the images.
"This find completes our picture of the first representatives of modern man and throws light on the debate as to whether he descended from Neanderthal man or was an immigrant from the Middle East," he said.
The find supports recent DNA evidence that modern Homo sapiens were not related to Neanderthal man, the professor said.
He added: "The traces we have found show a clean break between Neanderthal and modern man both in terms of culture and lifestyle. There is an abrupt change in the techniques of decoration and the use of flint and bone tools. Everything changes, in a radical, brutal fashion."
Guardian Unlimited © Guardian Newspapers Limited 2003
http://www.guardian.co.uk/print/0,38...103681,00.html"
This does not refute your comment, but it does help clarify some of it. I believe there is also a thread on this site that references a bone flute. While not cave art, music seems to me a very important expression of art. I have also seen examples of "dot art", for lack of a better term, forming geometric shapes and symbols, that I believe were attributed to Neandertal. I will have to re-find the references.
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OTHER (confusion over semantics of speciation):
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Precisely what do you mean by "crossing the boundary from one species to another"?
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Forgive the imprecision in my choice of linguistic expression. I had no reason to believe my words would be interpreted as implying the crossing from one family of animals into another, dragonflies becoming wombats or some such. I suppose it is inevitable that a person with a focus on science would demand explicitly precise language, and considering the confusion even among its own ranks regarding proper linguistic delineation and distinction, it must be of necessity.
Some of us, however, are more poetic in our expression. This does leave room for semantic interpretation and cause for misunderstanding, but it also allows for the beauty of the word to shine. Beauty, I think, is something science all too often overlooks. Sometimes words are allegorical, after all. I simply need to recall that I must reinterpret my musings, and focus on my intended audience, and try to write to them at their level, in their language. Of course, this can be difficult if they cannot fully agree amongst themselves as to specifics of nomenclature, which leaves me confused as to how to get my points across in their language.
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The other way to get a new species that we have discussed is through population isolation. A single species is split into two species. This has also been documented both by experiment and in nature. And I don't think that can be called crossing the boundary either. It is more in the nature of erecting a boundary where there was none before.
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Agreed, I have not attempted to refute this basic premise. My only exception to this has been that some related species have been re-introduced only to cross and hybridize, which renders the "species" distinction in question in these instances.
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The other way for a species to change is by phyletic gradualism. This is a gradual accumulation of changes in one species such that the species at the end of the transformative process is different from the initial stock. When phyletic gradualism occurs over time, it has to be inferred from the morphology of fossil sequences as one cannot directly test whether the newer species could or could not interbreed with the ancestral species.
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This is conjectural supposition. It is not unfounded, but it is not proven, by its nature.
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But we also see examples of phyletic gradualism in which all the gradations from one species to another are contemporaneous. Such sequences are called "ring species".
"The Arctic Ocean polar ice cap limits the species range of Sea Gulls to its periphery. Races from Siberia freely interbreed with races from America. Races from America freely interbreed with races from Europe. Going the other way, Races from Siberia freely interbreed with races from the Caucauses. However, Western European herring gull (Larus argentatus) do not interbreed with the lesser black-backed gull (Larus fuscus) from Centrial Europe where these races of Sea Gulls occur together in northern Europe. So, all along the ring that circumnavigates the globe about the Arctic there is gene flow but where the two ends of the ring meet in Europe there is no gene flow." http://geowords.com/histbooknetscape/f26.htm
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Very well, but then we have this to deal with...
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It is very important to remember that evolution relates to species i.e. to populations, not to individuals. So we need to break down your question into more than one question.
1. If my pet chihuahua chooses not to mate with my neighbour's great dane, are they different species? Not necessarily. My pet chihuahua may just be finicky.
2. If chihuahuas in general choose not to mate with great danes in general, are they different species? Possibly. If they were the only breeds of dog in existence we could predict that this sexual preference on the part of chihuahuas would lead to them becoming separate species if they are not already.
3. If chihuahuas are physically incapable of mating with great danes (and I believe they are), are they different species? They certainly would be if they were the only two breeds of dog.
What prevents us from calling chihuahuas and great danes different species is the existence of other breeds of dogs, some of which can breed with chihuahuas, and some of which can breed with great danes, and which also breed with each other. So even if chihuahuas and great danes cannot interbreed directly, there is still an avenue of gene flow from one population to another via the intermediate breeds. This situation is analogous to a ring species, though I don't know that biologists would apply that term to dogs.
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So, what differentiates between the seagull species that interbreed, and the dog breeds that interbreed? It seems to me, by all of the effort put forth in this discussion to this point, that by the definitions established, the seagulls are not species but breeds (or varieties). Either that, or the dogs are not breeds, but species that are able to interbreed. This is the exact confusion I am running into across the board in my research. So I must assume that "species" and "breed/variety" are effectively interchangeable, depending on the particular researcher, even though most ascribe to the requisite definition of species as not being able to intermingle. Does this better establish my quandary?
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MISC:
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There is no doctrine of evolution as evolution is not a religious outlook. There is a theory of evolution which has a great deal of evidential support.
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Ah, now, we could go here very easily, but it would derail this thread. You will find a bit about my take on this issue in the thread "Religion as a Meme." In short, evolution is a dogma, science is a religion.
There is still much to cover that I haven't had the time for as yet. Already I have invested several hours into this post, I must go for now. Thanks for your input! I always enjoy an intelligent discussion.
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