RE: Regulating Evolution (Full Version)

All Forums >> [Theology] >> Science & Origins



Message

Bettawrekonize -> RE: Regulating Evolution (5/1/2008 2:35:31 AM)

quote:

ORIGINAL: essentialsaltes

quote:

ORIGINAL: Bettawrekonize

Also, why haven't other organisms found different pathways earlier on that have lead to an organism that is very close to optimal


They have. Squid eyes, for instance, do not suffer from the defects of vertebrate eyes that I mentioned.


You didn't quote my entire sentence.



Bettawrekonize -> RE: Regulating Evolution (5/1/2008 2:59:53 AM)

quote:

ORIGINAL: gluadys
So you don't think it might be because most species are relatively near a fitness peak?


I think such a claim is unfalsifiable. We know that when we make an organism less adapt for an environment (ie: when dogs lose the genetic ability to live in the wild) the organism won't gain back the ability as well as their ancestors unless external DNA is introduced, which would suggest that fitness peak really has nothing to do with it. Presumably, there is a pathway to get to the fitness peak of the ancestors (if UCD is true) yet it is not demonstrated to occur.

quote:


They certainly co-exist with natural selection, but they are not always subject to natural selection. In some situations, neutral selection is thought to be more dominant than natural selection.


Neutral selection, maybe, but harmful selection, no. They are subject to natural selection and there is no reason why natural selection would favor an organism that is attracted to an inferior spouse. This increases the odds that the children would be attracted to an inferior (less fit) spouse which means that the generation would not survive as well as an organism that is attracted to a superior (more fit) spouse. Natural selection would favor an organism attracted to a superior (more fit) spouse and its generation more than it would favor an organism attracted to an inferior spouse.

quote:


But not by other types of selection.


Again, other types of selection are subject to natural selection.

quote:


So it depends on which mode is in the driver's seat. That is what the guppy experiment was about. Females tend to prefer brightly coloured males. But brightly coloured males are an easy target for predators. So one would expect guppies not to be brightly coloured if natural selection prevails over sexual selection. And we do find that many guppies are not brightly coloured.


Again, why would natural selection select a female that is attracted to a less fit male? I would expect natural selection to favor the opposite and sexual selection is subject to natural selection. The females that are attracted to a more fit organism are more likely to find a spouse while the ones that aren't are less likely to find a spouse. They are also more likely to have descendants that are attracted to a more fit organism and those descendants are more likely to find a spouse (since natural selection favors the more fit organism), and eventually, natural selection would weed out the females that are attracted to a less fit organism. The females attracted to a less fit organism are likely to have children that are less fit and those children will likely be selected against, hence making it more difficult for their descendants to survive.

quote:


The researchers theorized that in places where the guppies were brightly coloured there were few if any predators. Then they began a census of predator species and found they were right.


In this case, the organisms are not less fit.

quote:


So whenever the pressure of natural selection was lessened because of lack of predators, sexual selection took over and generated brighter colours.


But sexual selection is still subject to natural selection.

quote:


I think you must mean a different post. That one says nothing relevant to this conversation.


I think not. I think your fitness peak argument has pretty much been refuted. We'll let others decide though, since this isn't a tax funded forum (ie: public schools) where criticisms and opposing views of evolution are dishonestly censored.

quote:


Actually no. If an organism were actually at the optimum fitness, for every characteristic, it would follow that every mutation which could possibly happen would remove it from the optimum.


I know. The point is that more mutations are harmful than beneficial despite the fact that organisms are not optimal.

quote:


So that actually agrees with the fitness thesis.


Whitch, BTW, is unfalsifiable.

quote:


Most organisms are not at optimum for every characteristic.


Yet, more mutations are harmful than beneficial.

quote:


If the fitness landscape changes (because of some environmental difference) a species that was near a fitness peak may find itself somewhat removed from a fitness peak.


The point is that it doesn't seem to get back to the ancestors fitness peak when the environment changes back (as I have pointed out in the case of human selected dogs), which suggests that fitness peak has nothing to do with it. More mutations are harmful than beneficial and there is no reason to suggest fitness peak plays much of a role.

quote:


Combined with historical constraint, such as essentialsaltes has discussed, this means organisms are generally not perfect.


Again, which supports the notion that they are not close to their fitness peak, yet mutations tend to be more harmful than beneficial. If they were optimal, they would be at their fitness peak.

quote:


And again you have misread the argument.


What argument?



essentialsaltes -> RE: Regulating Evolution (5/1/2008 9:51:25 AM)

quote:

ORIGINAL: Bettawrekonize

quote:

ORIGINAL: essentialsaltes

quote:

ORIGINAL: Bettawrekonize

Also, why haven't other organisms found different pathways earlier on that have lead to an organism that is very close to optimal


They have. Squid eyes, for instance, do not suffer from the defects of vertebrate eyes that I mentioned.


You didn't quote my entire sentence.


Welp, I can assure you that there are no vertebrate squid inhabiting that niche.



gluadys -> RE: Regulating Evolution (5/1/2008 11:19:42 AM)

quote:

ORIGINAL: Bettawrekonize
Presumably, there is a pathway to get to the fitness peak of the ancestors (if UCD is true) yet it is not demonstrated to occur.


No, that is not the case. That is one of the things we mean by a historical constraint on evolution. You can't undo your species history, and that history can block the way back to the ancestral condition. In fact, it usually does, except in the case of recent and minor modifications such as a change in the beak size of Galapagos finches during a drought year.


quote:

In this case, the organisms are not less fit.


Right, but their fitness is defined as the ability to attract a mate (sexual selection) rather than by an adaptation to the environment (natural selection).

quote:

But sexual selection is still subject to natural selection.


In the sense that it takes a back seat when predation is a factor, yes. However, it was still operative , since even the camouflaged guppies continued to sport small flashes of colour near the tail as attractors to the females. When the natural selector (predation) was removed, the sexual selector predominated.

quote:

I know. The point is that more mutations are harmful than beneficial despite the fact that organisms are not optimal.


"fit" does not imply "optimally fit". Any degree of fitness is capable of being reduced. Most species are not and cannot be at optimal fitness, but most are near a peak of fitness. If you are 3/4 of the way up the mountain, there is more scope for going down than up.


You are assuming that the placement near a fitness peak in some sense makes mutations harmful. That is not the case. Mutations can be harmful or beneficial no matter how a species is placed near a fitness peak. But the closer it is to a fitness peak the less scope there is for improvement, so their are not many openings for a mutation to be beneficial. In fact, if a species were at optimum, ALL mutations would necessarily be harmful, as all mutations would necessarily remove them from the optimum.

The fact that many mutations are harmful is a reflection of the fact that most species are reasonably (though not optimally) adapted to their niche. Which is just another way of saying that mutations are not intrinsically harmful or beneficial, but only in relation to their environment.



swan42 -> RE: Regulating Evolution (5/5/2008 3:28:18 AM)

quote:

ORIGINAL: Bettawrekonize

quote:

ORIGINAL: benelchi
However, evolutionary biologists have long argued the presence of "garbage" DNA was proof of evolution because they said that there was no other explanation about why the same "garbage" would be present in "later generations".


This makes no sense. Useless DNA would not be subject to natural selection so there should be less to conserve it against the effects of random mutation.


And in fact this is exactly what happens in reality. DNA testing for purposes of identifying individuals focuses on DNA regions that are known to have no biological function. Sequences that have no biological function are not well conserved and yes they do suffer a great deal of random mutations. Lack of sequence conservation is exactly what is required to identify unidentified victims and connect suspects to crimes.

If on the other hand, one used the sequence region for Hemoglobin (a useful sequence with a known function that is well conserved) as a means of identifying individuals, then probability of two people having the same DNA sequence for Hemoglobin is quite high.

The nonconservative effect of random mutations on a region of useless DNA does not automatically yield a quick loss of DNA in one generation or even a 1000 generations, rather there is a continuum of DNA sequence change over many generations. Some changes are just a change in code, some are a loss of DNA base pairs.



swan42 -> RE: Regulating Evolution (5/5/2008 3:51:38 AM)

quote:

Again, it may be due to some oversight in my knowledge of the relevant processes, but shouldn't the same thing apply to DNA? We should expect a lot of things that contribute to the survival, and therefore propagation of DNA, along with relatively few things that are either useless or harmful, that don't contribute to propagation. If this is correct, only things that have recently become useless or harmful should be in the DNA, and those should be weeded out as time goes on.
Of course, this is all moot speculation if there's no cost for waste at the genetic level.


You are absolutely correct on these details Real_Solitude, but overlook some of the big picture. Keeping a given non-functional DNA sequence around from one generation to the next has only a marginal expense to an individual organism. I keep a heavy car jack in my trunk just in case I have a flat tire. It costs a little extra gasoline to move the weight of the car jack, but that small cost pays off when I have a flat tire. The same scenario applies when selective forces encourage a rarely used DNA sequence to be retained longer than would be expected given its apparent lack of function. The weed-out process for truly non-functional DNA sequences can take many generations and a very long time to completely remove a useless DNA sequence from a genome. Or, the weed-out process can happen very quickly.... it just depends the circumstances.



Bettawrekonize -> RE: Regulating Evolution (5/12/2008 11:23:27 PM)

quote:

ORIGINAL: gluadys

quote:

ORIGINAL: Bettawrekonize
Presumably, there is a pathway to get to the fitness peak of the ancestors (if UCD is true) yet it is not demonstrated to occur.


No, that is not the case. That is one of the things we mean by a historical constraint on evolution. You can't undo your species history, and that history can block the way back to the ancestral condition. In fact, it usually does, except in the case of recent and minor modifications such as a change in the beak size of Galapagos finches during a drought year.


Which gives no evidence to the notion that it was possible to get to the historical condition to begin with. Basically, the notion that we can get to the historical condition via unguided naturalistic processes is unfalsifiable.

quote:


Right, but their fitness is defined as the ability to attract a mate (sexual selection) rather than by an adaptation to the environment (natural selection).


The point is that they are still subject to natural selection.

quote:


In the sense that it takes a back seat when predation is a factor, yes. However, it was still operative , since even the camouflaged guppies continued to sport small flashes of colour near the tail as attractors to the females. When the natural selector (predation) was removed, the sexual selector predominated.


But what you said was, "However, other types of selection may introduce less fitness in one respect or another" and I am merely pointing out that, when the predation was removed, these organisms are not less fit. So they are not introducing less fitness.

quote:


"fit" does not imply "optimally fit". Any degree of fitness is capable of being reduced. Most species are not and cannot be at optimal fitness, but most are near a peak of fitness. If you are 3/4 of the way up the mountain, there is more scope for going down than up.

You are assuming that the placement near a fitness peak in some sense makes mutations harmful. That is not the case. Mutations can be harmful or beneficial no matter how a species is placed near a fitness peak. But the closer it is to a fitness peak the less scope there is for improvement, so their are not many openings for a mutation to be beneficial. In fact, if a species were at optimum, ALL mutations would necessarily be harmful, as all mutations would necessarily remove them from the optimum

The fact that many mutations are harmful is a reflection of the fact that most species are reasonably (though not optimally) adapted to their niche. Which is just another way of saying that mutations are not intrinsically harmful or beneficial, but only in relation to their environment.


But when we move organisms down the hill (ie: domesticated dogs) and stick them in the wild, they do not climb back up the hill (unless genetic information gets introduced to them from outside). Even if we try to climb them up gradually, it would not happen. Same thing is true with the virus and petri dish example. So really, there is no evidence supporting your fitness peak hypothesis and much evidence contradicting it. Organisms seem to go down fitness peaks and they seem to loose their adaptability. It's as if they are able to adapt to certain conditions and reach a fitness peak for each condition through a level of variation. However, whenever they adapt to an environment and change fitness peaks, it tends to reduce their fitness peaks with respect to other environments (ie: previous ones) and is more likely to reduce it than to increase it. So the net effect seems to be that their fitness peak for each possible environment tends to get reduced over time.



drj11 -> RE: Regulating Evolution (5/12/2008 11:26:11 PM)

quote:

ORIGINAL: Bettawrekonize

quote:

ORIGINAL: gluadys

quote:

ORIGINAL: Bettawrekonize
Presumably, there is a pathway to get to the fitness peak of the ancestors (if UCD is true) yet it is not demonstrated to occur.


No, that is not the case. That is one of the things we mean by a historical constraint on evolution. You can't undo your species history, and that history can block the way back to the ancestral condition. In fact, it usually does, except in the case of recent and minor modifications such as a change in the beak size of Galapagos finches during a drought year.


Which gives no evidence to the notion that it was possible to get to the historical condition to begin with. Basically, the notion that we can get to the historical condition via unguided naturalistic processes is unfalsifiable.

quote:


Right, but their fitness is defined as the ability to attract a mate (sexual selection) rather than by an adaptation to the environment (natural selection).


The point is that they are still subject to natural selection.

quote:


In the sense that it takes a back seat when predation is a factor, yes. However, it was still operative , since even the camouflaged guppies continued to sport small flashes of colour near the tail as attractors to the females. When the natural selector (predation) was removed, the sexual selector predominated.


But what you said was, "However, other types of selection may introduce less fitness in one respect or another" and I am merely pointing out that, when the predation was removed, these organisms are not less fit. So they are not introducing less fitness.

quote:


"fit" does not imply "optimally fit". Any degree of fitness is capable of being reduced. Most species are not and cannot be at optimal fitness, but most are near a peak of fitness. If you are 3/4 of the way up the mountain, there is more scope for going down than up.

You are assuming that the placement near a fitness peak in some sense makes mutations harmful. That is not the case. Mutations can be harmful or beneficial no matter how a species is placed near a fitness peak. But the closer it is to a fitness peak the less scope there is for improvement, so their are not many openings for a mutation to be beneficial. In fact, if a species were at optimum, ALL mutations would necessarily be harmful, as all mutations would necessarily remove them from the optimum

The fact that many mutations are harmful is a reflection of the fact that most species are reasonably (though not optimally) adapted to their niche. Which is just another way of saying that mutations are not intrinsically harmful or beneficial, but only in relation to their environment.


But when we move organisms down the hill (ie: domesticated dogs) and stick them in the wild, they do not climb back up the hill (unless genetic information gets introduced to them from outside). Even if we try to climb them up gradually, it would not happen. Same thing is true with the virus and petri dish example. So really, there is no evidence supporting your fitness peak hypothesis and much evidence contradicting it.


Apparently you've never been to a 3rd world country, where once domesticated dogs have pretty much reverted to a wild state, and exist as scavengers surviving on their own.



Bettawrekonize -> RE: Regulating Evolution (5/12/2008 11:31:25 PM)

quote:

ORIGINAL: drj11
Apparently you've never been to a 3rd world country, where once domesticated dogs have pretty much reverted to a wild state, and exist as scavengers surviving on their own.


But do they survive as well as their ancestors in the same environment as their ancestors and is any genetic information being introduced from outside? Is their survival assisted by humans? Do you have sources?



Bettawrekonize -> RE: Regulating Evolution (5/12/2008 11:32:33 PM)

quote:

ORIGINAL: essentialsaltes
Welp, I can assure you that there are no vertebrate squid inhabiting that niche.


So?



drj11 -> RE: Regulating Evolution (5/12/2008 11:39:31 PM)

quote:

ORIGINAL: Bettawrekonize

quote:

ORIGINAL: drj11
Apparently you've never been to a 3rd world country, where once domesticated dogs have pretty much reverted to a wild state, and exist as scavengers surviving on their own.


But do they survive as well as their ancestors in the same environment as their ancestors and is any genetic information being introduced from outside? Is their survival assisted by humans? Do you have sources?


If we take a freshwater fish that evolved from saltwater fish and dump it in the middle of the ocean, how do you think it will fare?

The wild dogs in third world countries (that I have visited), I'll grant you, arent hunting like yellowstone wolves, but they have adapted to a gradual change in their current environment. If environmental changes are too extreme, the organism will die. But gradual environmental change over time, would also allow the organism to adapt along with them.



Bettawrekonize -> RE: Regulating Evolution (5/12/2008 11:46:57 PM)

quote:

ORIGINAL: swan42
DNA testing for purposes of identifying individuals focuses on DNA regions that are known to have no biological function.


Or where biological function is not yet known.

quote:


Sequences that have no biological function are not well conserved and yes they do suffer a great deal of random mutations.


They are assumed not to be conserved (based on evolutionary presuppositions); however, perhaps they do have function. Maybe it's not that they aren't "conserved," perhaps it's that they are two different sequences altogether (designed for two different functions).

quote:


Lack of sequence conservation is exactly what is required to identify unidentified victims and connect suspects to crimes.


If the sequences are not conserved then it is not the case that the same "garbage" is present in, "later generations."



Bettawrekonize -> RE: Regulating Evolution (5/12/2008 11:59:42 PM)

quote:

ORIGINAL: drj11
If we take a freshwater fish that evolved from saltwater fish and dump it in the middle of the ocean, how do you think it will fare?

The wild dogs in third world countries (that I have visited), I'll grant you, arent hunting like yellowstone wolves, but they have adapted to a gradual change in their current environment.


But there seems to be limits as to how well they will adapt. That is, they do not survive as well as their ancestors, even if by gradual modification (unless new DNA is introduced).

quote:


If environmental changes are too extreme, the organism will die. But gradual environmental change over time, would also allow the organism to adapt along with them.


Well, it is difficult to discuss a topic by which there are no published studies to go by. Your account maybe anecdotal and it could leave out a lot of useful information. Do you have any specific sources you would like to reference? I think the research is slowly starting to point away from the notion that a gradual environmental change would bring these dogs back to the fitness peak of their ancestors. It seems to show that they can reach a certain fitness peak through changes that are easy to overcome but once those changes have occurred and changes that are difficult to overcome via RM + NS are required, they do not occur. While I have not read the edge of evolution (I don't have the book and I only read part of Darwins Black box by Behe) the evidence seems to support my understanding of the Edge of evolution from what I have read about it (at least as far as what Jhud and others have said).



swan42 -> RE: Regulating Evolution (5/13/2008 2:17:32 AM)

quote:

ORIGINAL: Bettawrekonize

quote:

ORIGINAL: swan42
DNA testing for purposes of identifying individuals focuses on DNA regions that are known to have no biological function.


Or where biological function is not yet known.

No, I meant exactly what I said. We know these regions have no function.
Not, "We don't know the function of these regions".
quote:


quote:


Sequences that have no biological function are not well conserved and yes they do suffer a great deal of random mutations.


They are assumed not to be conserved (based on evolutionary presuppositions); however, perhaps they do have function. Maybe it's not that they aren't "conserved," perhaps it's that they are two different sequences altogether (designed for two different functions).

No, I mean they are not conserved and highly highly variable between individuals and do not have active Open Reading Frames; they do not code for genes.
quote:


quote:


Lack of sequence conservation is exactly what is required to identify unidentified victims and connect suspects to crimes.


If the sequences are not conserved then it is not the case that the same "garbage" is present in, "later generations."


No in the short term; Not exactly in the long term.

Since these regions have no function, mutations that occur in these regions are not selected against. So "new garbage" accumulates without detrimental consequencs.

1. The frequency of new garbage accumulation in mitochondrial DNA is estimated at one mutation per 300 to 600 generations.

2. Excluding the case of mitrochondia and Y chromosomes, the non-functional regions of human DNA have mother and father contributions (ala Mendelian Genetics).

3. Recombination and Crossover further scrambles the code sequence when the rules of Mendelian Genetics fail to apply.



swan42 -> RE: Regulating Evolution (5/13/2008 2:39:42 AM)

quote:


But there seems to be limits as to how well they will adapt. That is, they do not survive as well as their ancestors, even if by gradual modification (unless new DNA is introduced).


Limits?? You don't understand evolution if you make that statement. The limit of a wild dog's genetic disposition is determined by the number of generations and the environment., not by the concept of evolution itself.

Evolution does not require perfect adaptation; only survival. A Bichon Frisé won't last one generation, but other Spitz type dogs (Husky, Samoyed, Akita) already begin with 'wild dog' physical attributes that are quickly emphasized in a few generations.

Yes, new DNA is introduced; very very slowly (mutation) and quickly (Labradors breeding with Bulldogs) and suddenly (wild dog breeding with a wolf).

Russian studies of the Red Fox offers the counter-point to this topic. http://en.wikipedia.org/wiki/Tame_Silver_Fox

Russians domesticated the Red Fox over 50 generations and discovered that behavioral genes were associated with genes that affect the appearance of the Red Fox. A tame Silver Fox "looks cute". They became dog-like in appearance.

quote:


I think the research is slowly starting to point away from the notion that a gradual environmental change would bring these dogs back to the fitness peak of their ancestors.

(ignoring for the moment that "fitness peak" is relative to the environment")
If the Red Fox can become tame in 50 generations, then 5000 generations could turn the dog into a wolf.
There is a non-zero probability that all wolf genes are still present in varying combinations among all breeds of domesticated dogs.


trivia:
My co-worker owns (owned, 1 died) two of the F2 generation dogs mentioned in this article.
http://www.newscientist.com/article/mg13818790.500-search-for-genes-that-make-mans-best-friend-.html



gluadys -> RE: Regulating Evolution (5/13/2008 7:31:11 AM)

quote:

ORIGINAL: Bettawrekonize

quote:

ORIGINAL: gluadys

quote:

ORIGINAL: Bettawrekonize
Presumably, there is a pathway to get to the fitness peak of the ancestors (if UCD is true) yet it is not demonstrated to occur.


No, that is not the case. That is one of the things we mean by a historical constraint on evolution. You can't undo your species history, and that history can block the way back to the ancestral condition. In fact, it usually does, except in the case of recent and minor modifications such as a change in the beak size of Galapagos finches during a drought year.


Which gives no evidence to the notion that it was possible to get to the historical condition to begin with. Basically, the notion that we can get to the historical condition via unguided naturalistic processes is unfalsifiable.


Well, that is a nice irrelevant response. Personally, I do not buy the notion that nature is ever unguided. However, the evidence for evolution and common ancestry stands on its own merits without referencing theology. So I will provide such support as one finds in nature, but I will not argue for lack of guidance. The latter is not a scientific debate and cannot be decided on scientific grounds.

quote:

quote:


Right, but their fitness is defined as the ability to attract a mate (sexual selection) rather than by an adaptation to the environment (natural selection).


The point is that they are still subject to natural selection.


Do you not understand the difference? I don't know why you belabour this point?

quote:

quote:


In the sense that it takes a back seat when predation is a factor, yes. However, it was still operative , since even the camouflaged guppies continued to sport small flashes of colour near the tail as attractors to the females. When the natural selector (predation) was removed, the sexual selector predominated.


But what you said was, "However, other types of selection may introduce less fitness in one respect or another" and I am merely pointing out that, when the predation was removed, these organisms are not less fit. So they are not introducing less fitness.


In other words, when the natural selection factor was removed, natural selection was relaxed.

quote:


But when we move organisms down the hill (ie: domesticated dogs) and stick them in the wild, they do not climb back up the hill (unless genetic information gets introduced to them from outside). Even if we try to climb them up gradually, it would not happen.


See drj11's posts.



Bettawrekonize -> RE: Regulating Evolution (5/13/2008 11:52:21 AM)

quote:

ORIGINAL: swan42
No, I meant exactly what I said. We know these regions have no function.
Not, "We don't know the function of these regions".


I know what you meant, but we are discovering more and more that these regions have function.

quote:


No, I mean they are not conserved and highly highly variable between individuals and do not have active Open Reading Frames; they do not code for genes.


I know what you meant, I was just giving other possible suggestions.

quote:


quote:


If the sequences are not conserved then it is not the case that the same "garbage" is present in, "later generations."

No in the short term; Not exactly in the long term.


Which was the point I was making.



Bettawrekonize -> RE: Regulating Evolution (5/13/2008 12:05:07 PM)

quote:

ORIGINAL: gluadys
Limits?? You don't understand evolution if you make that statement. The limit of a wild dog's genetic disposition is determined by the number of generations and the environment., not by the concept of evolution itself.


I am not referring to the concept of evolution, I am referring to the experimental evidence itself. The experimental evidence shows that there are limits, all the theories in the world do not change this.

quote:


Evolution does not require perfect adaptation; only survival.


I never said otherwise.

quote:


A Bichon Frisé won't last one generation, but other Spitz type dogs (Husky, Samoyed, Akita) already begin with 'wild dog' physical attributes that are quickly emphasized in a few generations.


Those attributes already exist though.

quote:


Yes, new DNA is introduced; very very slowly (mutation)


Again, the research seems to suggest there are limits as to how much adaptation this can cause.

quote:


and quickly (Labradors breeding with Bulldogs) and suddenly (wild dog breeding with a wolf).


and my point is that, unless new genetic information is introduced (that is already well adapted to the environment), then it seems to be the case that the domestic dogs that lost many of their ancestor traits required for surviving in the wild do not reach that peak again. Over generations, it seems to be the case that organisms become less able to adapt to a variety of conditions. The ancestors were able to adapt to domestic conditions and they were able to adapt to the wild. However, their descendants, which had traits that were strongly selected against (many traits that are good at adapting in wild conditions) are now only able to survive well in domesticated conditions. They have lost their ability to survive in wild conditions as well as their ancestors (unless new genetic information is introduced from outside) and there is no evidence to suggest that they will ever gain it back.

quote:


Russian studies of the Red Fox offers the counter-point to this topic. http://en.wikipedia.org/wiki/Tame_Silver_Fox

Russians domesticated the Red Fox over 50 generations and discovered that behavioral genes were associated with genes that affect the appearance of the Red Fox. A tame Silver Fox "looks cute". They became dog-like in appearance.


I do not think that this contradicts anything that I said. It just shows the same is true with foxes as with dogs, more examples of what I'm saying. The question is, would these tame foxes survive in the wild as well as their ancestors (assuming no new genes are introduced from wild foxes or direct human intervention)?

quote:


If the Red Fox can become tame in 50 generations, then 5000 generations could turn the dog into a wolf.


Do you have experimental evidence for this, or is it merely speculation?

quote:


There is a non-zero probability that all wolf genes are still present in varying combinations among all breeds of domesticated dogs.


But you still seem to be missing the point. It doesn't explain how these genes originated.



Bettawrekonize -> RE: Regulating Evolution (5/13/2008 12:09:25 PM)

quote:

ORIGINAL: gluadys
However, the evidence for evolution and common ancestry stands on its own merits without referencing theology.


I do not think there is enough evidence to suggest that UCD is true.

quote:


Do you not understand the difference? I don't know why you belabour this point?


I understand the difference.

quote:


In other words, when the natural selection factor was removed, natural selection was relaxed.


I know.

quote:


See drj11's posts.


What about them?



swan42 -> RE: Regulating Evolution (5/13/2008 12:20:00 PM)

quote:

ORIGINAL: Bettawrekonize

quote:

ORIGINAL: swan42
No, I meant exactly what I said. We know these regions have no function.
Not, "We don't know the function of these regions".


I know what you meant, but we are discovering more and more that these regions have function.

and I'm talking about regions of DNA are known to have no function, not regions that have no known function.
quote:



quote:


quote:


If the sequences are not conserved then it is not the case that the same "garbage" is present in, "later generations."

No in the short term; Not exactly in the long term.


Which was the point I was making.


The important thing about the garbage in this case is that it isn't the same garbage in later generations.. its completely different garbage.. that's why it is valuable in identifying an individual or excluding a suspect in a criminal investigation.



Bettawrekonize -> RE: Regulating Evolution (5/13/2008 12:30:39 PM)

quote:

ORIGINAL: swan42
and I'm talking about regions of DNA are known to have no function, not regions that have no known function.


Or, it could be the case that the functions are not yet known.

quote:


The important thing about the garbage in this case is that it isn't the same garbage in later generations.. its completely different garbage.. that's why it is valuable in identifying an individual or excluding a suspect in a criminal investigation.


I was just pointing out that what benelchi said doesn't make sense and you seem to agree here. As far as UCD, none of this really seems that relevant.



swan42 -> RE: Regulating Evolution (5/13/2008 12:33:49 PM)

quote:


But do they survive as well as their ancestors in the same environment as their ancestors and is any genetic information being introduced from outside? Is their survival assisted by humans? Do you have sources?

quote:


quote:



Limits?? You don't understand evolution if you make that statement. The limit of a wild dog's genetic disposition is determined by the number of generations and the environment., not by the concept of evolution itself.



I am not referring to the concept of evolution, I am referring to the experimental evidence itself. The experimental evidence shows that there are limits, all the theories in the world do not change this.




Hasty generalization. The anecdotal evidence (these aren't experiments of any kind) show that dogs adapt to living in the wild. Your desire that they acquire wolf attributes to live in the wild over-simplifies the question. Wolves themselves have declined in the past 100 years indicating they are not particularly well-adapted to their current environment.. Those nasty ranchers keep shooting wolves.

As for mis-understanding the limits involved evolution.

1. They do not have the same environment as their ancestors. They have an environment that interacts with the 21st century.
2a. The experiment is not over, we have to wait at least as long as it took to domesticate wolves in the first place. See you in 10,000 years.
2b. Or we have to speed up the process with human intervention.



Bettawrekonize -> RE: Regulating Evolution (5/13/2008 12:41:47 PM)

quote:

ORIGINAL: swan42
Hasty generalization. The anecdotal evidence (these aren't experiments of any kind) show that dogs adapt to living in the wild. Your desire that they acquire wolf attributes to live in the wild over-simplifies the question.


I am not asking that they acquire wold attributes, I am asking that they reach the same fitness peak.

quote:


Wolves themselves have declined in the past 100 years indicating they are not particularly well-adapted to their current environment.. Those nasty ranchers keep shooting wolves.


so?

quote:


As for mis-understanding the limits involved evolution.

1. They do not have the same environment as their ancestors. They have an environment that interacts with the 21st century.


But when you stick them in the environment of their ancestors, they do not survive as well.

quote:


2a. The experiment is not over, we have to wait at least as long as it took to domesticate wolves in the first place. See you in 10,000 years.


It maybe the case that such evolution takes 10,000 years, but at the moment, this is unfalsifiable and hence unscientific. It's a faith based statement. Thus far, the evidence seems to suggest that you are wrong. The virus and petri dish example is another example of this.

Organisms seem to have an ability to adapt at a certain level to each type of environment (they have a fitness peak for each environment), but if there is a trait that is strongly selected against in one environment (as in the case of domesticated dogs where many wild traits are selected against) such that the traits disappears from a population and the trait is needed for another environment (ie: the wild), the organism will not be able to adapt as well to that environment as its ancestors would be able to (unless it acquires that trait). It is easy for an organism to reach its current fitness peak for each environment, but once its maximum fitness peak for an environment has been reduced (ie: in the case of domesticated dogs, the maximum fitness peak for the wild environment is reduced), it does not gain it back unless it acquires the necessary traits from outside.

quote:


2b. Or we have to speed up the process with human intervention.


But nature is unable to insert genes into an organism the way a human can.



swan42 -> RE: Regulating Evolution (5/13/2008 12:43:53 PM)

quote:



quote:


Russian studies of the Red Fox offers the counter-point to this topic. http://en.wikipedia.org/wiki/Tame_Silver_Fox

Russians domesticated the Red Fox over 50 generations and discovered that behavioral genes were associated with genes that affect the appearance of the Red Fox. A tame Silver Fox "looks cute". They became dog-like in appearance.



I do not think that this contradicts anything that I said. It just shows the same is true with foxes as with dogs, more examples of what I'm saying. The question is, would these tame foxes survive in the wild as well as their ancestors (assuming no new genes are introduced from wild foxes or direct human intervention)?


No, these tame foxes would not do well in the wild, to think so is ridiculous. I would however expect them to do well on the border of wild and tame and have the opportunity, but not the expectation, to revert back to completely wild behaviors in at least 50 generations. They can still catch mice, and unlike their wild relatives, they can steal food from people without fear.

I think it shows that at least 50 generations are required to shape a Canid species from wild to tame and vice versa. To move from tame to wild 500 or 5000 generations might do the job, but at least 50 would be required. I'm talking about a minimum number of generations, not the maximum number of generations.



Bettawrekonize -> RE: Regulating Evolution (5/13/2008 12:54:42 PM)

quote:

ORIGINAL: swan42
No, these tame foxes would not do well in the wild, to think so is ridiculous. I would however expect them to do well on the border of wild and tame and have the opportunity, but not the expectation, to revert back to completely wild behaviors in at least 50 generations. They can still catch mice, and unlike their wild relatives, they can steal food from people without fear.


The point is that it's possible for their wild relatives to adapt to tame environments. Their wild relatives had more diversity, and these domesticated foxes are examples of wild animals adapting to domesticated environments.

quote:


I think it shows that at least 50 generations are required to shape a Canid species from wild to tame and vice versa.


I think they can go from wild to tame because they lose many of the characteristics that humans are strongly selecting against in domestic conditions. I don't know about going back to the wild state (fitness peak of their ancestors) though.

quote:


To move from tame to wild 500 or 5000 generations might do the job, but at least 50 would be required. I'm talking about a minimum number of generations, not the maximum number of generations.


At this point, most of what you seem to indicate seems to be speculation. The studies do not seem to support your contentions. It could be the case that 5,000 generations would bring them back, but that's just speculation.

Another thing to note is that, with fruit flues, bacteria, and viruses, we are able to observe far more generations, and the evidence doesn't seem to support your contentions here either. The virus and petri dish example I gave earlier is an example of this.



Page: <<   < prev  2 3 4 [5] 6   next >   >>



Forum Software © ASPPlayground.NET Advanced Edition 2.5 ANSI