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Author Topic:   The End of Evolution By Means of Natural Selection
nwr
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Posts: 6408
From: Geneva, Illinois
Joined: 08-08-2005
Member Rating: 5.1


Message 136 of 851 (552452)
03-29-2010 9:09 AM
Reply to: Message 124 by Faith
03-28-2010 2:54 PM


Faith's questions
Hi Faith. I initially did not respond in order to minimize the "piling on" problem. I assumed others would adequately cover most of the points. However, you requested response in Message 129, so I am complying.
Note that some of my responses might differ from those of the biologists. I have been researching the principles of learning, and I am influenced by that research, as I do consider evolution to be a kind of learning system.
Faith writes:
1) In domestic breeding -- let's stick to dogs -- do you agree that you get and maintain a breed by being sure you breed it with its own type?
To "get" a breed, you select dogs with the desired characteristic, and breed them. Yes, you then breed within type. But, as far as I know, that is not sufficient. You also have to continue selection, for the dogs are not guaranteed to "breed true".
Faith writes:
2) Do you agree that this is to protect the breed's particular allele complement from contamination from alleles of other dog types?
Yes, but I would prefer to say it is to increase the probability that the pups will have the desired characteristics.
Faith writes:
3) Do you agree that any dog breed possesses a very limited genetic diversity with respect to the total dog population?
Any individual dog contains limited diversity, compared to the total population.
The breeding pool also has less diversity than dogs as a whole. But much of that is due to it being a far smaller group. Some of the alleles that the breeder wants to suppress will still be present, but at a lower frequency.
And some of the traits being bred for are the result of combinations of many alleles, rather than due to single alleles. In that case, the alleles might be very similar to what is in the general dog population, but the probabilities of particular combinations will be different and will favor the traits the breeder wants.
Faith writes:
4) Do you agree that it is its limited genetic diversity that is the basis for the characteristics of the breed itself and that if there is any increase in the genetic diversity the breed will lose its character at least to some extent?
The effect of the breeding is it increase the probability of the desired traits, and reduce the probability of undesired traits. The breeding pool has been selected to produce those changes in probability. But that does not require the complete elimination of the alleles responsible for undesired traits. The genetic diversity of the breed might not be much different from that of a similar sized population group, but the probability distribution will be different and that is what leads to a successful breeding program.
Faith writes:
5) Do you agree that Darwin based his natural selection on domestic selection?
No. Some of his ideas came from his knowledge and experience with domestic breeding, but the initial insight came from his voyage on the HMS Beagle, and was particularly influenced by the biota of the Galapagos islands.
Faith writes:
6) Do you agree that natural selection is the "engine of evolution?"
No, I have previously expressed disagreement with that. Evolution depends on selection and on variation. In my opinion the generation and maintaining of variation within the population is at least as important as selection.
Faith writes:
7) Do you agree that the end goal of evolution is speciation or is evolution simply any change at all whether it ever leads to speciation or not?
As others have indicated, evolution has no goals. However, I think it fair to say that living things have a "drive" to survive and persist, perhaps by producing future generations. And this biological "drive" is an important part of what drives evolution.

This message is a reply to:
 Message 124 by Faith, posted 03-28-2010 2:54 PM Faith has not replied

  
Hyroglyphx
Inactive Member


Message 137 of 851 (552453)
03-29-2010 9:14 AM
Reply to: Message 124 by Faith
03-28-2010 2:54 PM


Re: ANOTHER MID-THREAD RECON
1) In domestic breeding -- let's stick to dogs -- do you agree that you get and maintain a breed by being sure you breed it with its own type?
Sure, but inbreeding becomes a problem especially if isolation is present. Mutts are far more genetically diverse than pure breeds.
2) Do you agree that this is to protect the breed's particular allele complement from contamination from alleles of other dog types?
Well, if you want a pure breed dog, then I suppose yes.
3) Do you agree that any dog breed possesses a very limited genetic diversity with respect to the total dog population?
Yes
4) Do you agree that it is its limited genetic diversity that is the basis for the characteristics of the breed itself and that if there is any increase in the genetic diversity the breed will lose its character at least to some extent?
What do you mean by "lose its character?"
5) Do you agree that Darwin based his natural selection on domestic selection?
No, not entirely. I would think Mendel would be more prone to this. Don't you recall the numerous excursions all over the planet? Don't you recall instances, like on the Galapagos, where he noticied distinct characteristics in their iguana population that differed considerably from other South American iguana? Those weren't domesticated and neither were most of his studies.
6) Do you agree that natural selection is the "engine of evolution?"
There are several factors, but that is one component within the engine.
7) Do you agree that the end goal of evolution is speciation or is evolution simply any change at all whether it ever leads to speciation or not?
I don't believe there is any "goal," as a goal would be indicative of intent. Change is simply an inevitability.

"Political correctness is tyranny with manners." -- Charlton Heston

This message is a reply to:
 Message 124 by Faith, posted 03-28-2010 2:54 PM Faith has not replied

  
Blue Jay
Member (Idle past 2697 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 138 of 851 (552469)
03-29-2010 10:45 AM
Reply to: Message 124 by Faith
03-28-2010 2:54 PM


Re: ANOTHER MID-THREAD RECON
Hi, Faith.
Like NWR, I refrained from responding to avoid overloading you. But, since you seem to be taking a poll of sorts, I suppose it would be more beneficial if I filled out the form and sent it in.
Faith writes:
1) In domestic breeding -- let's stick to dogs -- do you agree that you get and maintain a breed by being sure you breed it with its own type?
Like everyone else, I disagree with the get part here. My experience is in chicken breeding, but the principle is the same: a breed is defined by a key set of characteristics, and any animal that resembles these characteristics closely enough can be considered part of the breed (for the purposes of judging at fair competitions or selling commercially), even if most of the genotype of an individual animal actually comes from outside the breed (which it very often does in the case of chickens).
However, I do more or less agree with the maintain part.
-----
Faith writes:
2) Do you agree that this is to protect the breed's particular allele complement from contamination from alleles of other dog types?
I don’t know that I would word it that way (I think NWR worded it more accurately), but the basic idea is close enough to correct that I won’t spend any more time clarifying it. Just remember that selection (of any kind) doesn't act on the population, but on the individual, so it's inappropriate to cite "for the good of the group" as the underlying cause of evolution.
-----
Faith writes:
3) Do you agree that any dog breed possesses a very limited genetic diversity with respect to the total dog population?
This is a given, since genetic diversity is proportional to the number of individuals in a population (because of mutation), and a population (or pure breed, in this case) of dogs obviously has fewer individuals than the sum of individuals in all dog breeds together.
The trouble is that, in reality, purebreds are extremely rare (rarer than vendors would have us believe). Breeds are not really defined by genotype, but by phenotype (and usually only by a specific set of phenotypic characters, rather than by the entire phenotype), so, like Paul said, we don’t really know how the genetic diversity is distributed among and within different breeds, or how the lack of allelic diversity for breed-defining genes correlates with allelic diversity for genes that do not define the breed.
-----
Faith writes:
4) Do you agree that it is its limited genetic diversity that is the basis for the characteristics of the breed itself and that if there is any increase in the genetic diversity the breed will lose its character at least to some extent?
No. I disagree with the second part of this question (the first part is pretty much a crap shoot, too). A breed is not defined by genotype, so, as long as the increased genetic diversity does not affect the subset of phenotypic characters that define the breed, the breed will not be considered to have lost its character.
-----
Faith writes:
5) Do you agree that Darwin based his natural selection on domestic selection?
The basis of natural selection was not for Darwin to decide: he only discovered it; he did not invent it.
His understanding of natural selection was very likely influenced by his understanding of domestic selection (I haven’t looked into it in that much detail, though), but my reading of his work indicates that he recognized that there were some important distinctions, such as the lack of directional guidance by an intelligent overseer in the case of natural selection.
But, like Dr Adequate wrote, what we currently understand about natural selection is not constrained in any fashion by what may or may not have been Darwin’s primary influences while formulating the rudiments of modern evolutionary thought. Natural selection is not an idea that Darwin came up with: it is a real, observed process that Darwin was trying to describe, and that we, today, understand more completely and more accurately than he did in his day.
-----
Faith writes:
6) Do you agree that natural selection is the "engine of evolution?"
Even before the others responded, I was mentally answering this one with the steering wheel point that the others have used.
I maintain that mutation---which I use loosely to refer to all forms of alterations to the genome that result in new alleles or nucleotide sequences---is the ultimate source of all genetic diversity. This, in my mind, is what makes mutation, and not natural selection, the engine of evolution. Because natural selection is the closest equivalent to a guiding hand in evolution, it is more appropriately analogized as the steering wheel or rudder than the engine.
-----
Faith writes:
7) Do you agree that the end goal of evolution is speciation or is evolution simply any change at all whether it ever leads to speciation or not?
The second part is correct: evolution is simply any change at all, whether or not it leads to speciation. Like everyone else, I object to the goal imagery, but I’ll spare you another lecture (you apparently realize the inappropriateness of the term anyway): I mention it here only for the sake of clarity.
There are many aspects of the evolutionary worldview that should be thought of as the historical events, rather than the integral principles, of evolution. Natural history is a term used to describe the sequence of biological events that occur on Earth, extending well before the point when human history first began: it incorporates all of the historical components of evolution. Speciation is a process that is seen in the fossil record and the genetic evidence, and is thus appropriately seen as a part of natural history. Evolution, however, is the mechanism(s) behind the historical events and the theoretical principles used to describe the mechanism(s). Evolution can still occur in the absence of speciation.
In this debate, we are in the habit of referring to the Theory of Evolution, its mechanisms, its processes, and it outcomes, as one collective body of information that comprises one side of the debate (the evolution side). Speciation is certainly an integral requirement for our side of the debate, and if you defeat speciation, you will have dealt an insurmountable blow to our side of the debate; however, it needs to be made clear that speciation is not a principle of evolution, but a predicted outcome of it (one of many).
Remember also that speciation is as terminologically intractable as species is. In fact, an evolutionary event can only be assessed as speciation ex post facto: it would simply be considered a quantity of accumulated divergence between groups of organisms that resulted in drastically reduced rates of genetic intermixing. The thresholds of divergence and hybridization that define when speciation has occurred can only be determined heuristically, so it isn’t really a concrete, well-defined phenomenon.
-----
Again, sorry for the length and the detail, but I wanted to be thorough. And, there is much more that I wanted to include here, but I’ll forebear: there’s enough for you to digest already. I hope you take the time to consider all my points, because I honestly think that a simple analysis of what I (and others) have provided here should be sufficient to show that the problems you raised here are not insurmountable to the Theory of Evolution.
Edited by Bluejay, : "that equivalent" changed to "the equivalent" and "than the engine" added at the end of the that sentence.

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

This message is a reply to:
 Message 124 by Faith, posted 03-28-2010 2:54 PM Faith has not replied

  
Taq
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Posts: 9972
Joined: 03-06-2009
Member Rating: 5.5


Message 139 of 851 (552540)
03-29-2010 7:44 PM
Reply to: Message 134 by Percy
03-29-2010 6:24 AM


Re: ANOTHER MID-THREAD RECON
By the way, mutations do make contributions to breeding. For example, the dachshund's short legs originated through mutation (Scientists discover secret of why dachshunds have short legs).
Percy beat me to it. This is exactly what I was thinking reading this thread. Also, this is a dominant allele. You only need one copy of the mutation to produce the phenotype. If the wolf ancestors of chihuahuas had this DNA sequence then these wolf ancestors would have had short legs like the dachsund. The only way for this to work is for the mutation to occur in the dachsund lineage FIRST and then have it selected for SECOND, a two step process (the first step of which Faith continues to ignore).
Also, mutations in the same human gene result in dwarfism as well. Hmf, who would have figured.

This message is a reply to:
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RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 140 of 851 (552747)
03-30-2010 10:11 PM
Reply to: Message 85 by Faith
03-27-2010 4:07 PM


evolution and speciation and reality
I can get all your posts on the screen but I can't figure out how to reply to them as a group.
When you RIGHT-CLICK on the reply button and choose OPEN IN ANOTHER TAB then you can refer to any part of any of the messages on the other tab, just link them to the message with [mid=552231], where 552231 is the gray number in parenthesis of the message at the top, right after "Message 85 of 139" (in the case of message 552231).
You can also write out your reply in a text editor in the same fashion and then paste the whole thing into the reply for the last message. This has the advantage of keeping your message if the system fails (it happens). That is what I have done here.
There is ALWAYS a reduction in genetic diversity when you select out or isolate alleles and build a new population from this reduced group. Always.
There is always a reduction in any scenario predicated on the basis of reduction. In other words you are begging the question.
Sub-populations normally all start with the same mixture of alleles as the parent population, they are not parceled out in the formation of the sub-populations.
The sub-populations THEN acquire new mutations\alleles that are selected in response to their sub-population ecology. Whether these new mutations are shared with the parent population depends on the degree of gene flow between the populations.
Doesn't seem to work out that way in reality.
Curiously, you did not answer the question, only asserted what you believe to be the case. Interestingly it does seem to work out that way in reality.
Their differences from other human populations are not due to mutations but to their sharing among themselves a limited collection of genetic possibilities.
Their differences from other human populations are not due a limited collection of genetic possibilities, but to sharing entirely new mutations among themselves.
See how that works? Interestingly this also is what is observed in the field.
Curiously, a sub-population with "only a limited collection of genetic possibilities" that are only inherited from the parent population is just not capable of being different from the parent population. Any member of the sub-population with those genes would still be an individual in the parent population.
Human evolution from a supposed common ancestor with chimps couldn't have happened.
Fascinatingly, your opinion is completely incapable of altering reality in any way.
Amusingly, even your limited (incomplete, wrong) view of speciation even allows this to be the case, as all you need to have is the chimp population with the 1-3% "limited collection of genetic possibilities" particular to chimps while the human populations have the 1-3% "limited collection of genetic possibilities" particular to humans, while still sharing 95-98% of all the genetic possibilities.
If mutation does occur then this is true. You will have more genetic possibilities or more genetic diversity/variability in the population.
Multiple mutations occur with every birth.
True. And it's possible neither population loses any alleles, just changes frequencies.
True. Therefore reduction is not inevitable.
You are postulating a branching of populations that doesn't lose alleles, just shuffles them. That can happen but that's pretty slow evolution.
Interestingly, the data shows that evolution is slow, much slower than it needs to be (there is a lot of waste in natural evolution with oscillations, such as seen in the finches).
Really it seems you have a brand new theory of evolution. You have something like a theory of evolution by mutation rather than evolution by natural selection.
Amazingly, (real) evolution requires both a source of new variation AND a means to selectively sort the adaptive ones from the anti-adaptive ones.
This either natural selection OR mutation view is a false creationist strawman. Real evolution (ie - as the term is used by biologists) uses both AND even some other mechanisms.
Sure, if you have populations that are constantly acquiring new alleles through mutation and never lose any you can get change or some kind of evolution over time but it won't be adaptive evolution by natural selection and in fact how is it going to develop a phenotypic characteristic for the whole population either? Seems you would only get a population of the same species with lots and lots of different varieties of that species all mixed together.
Agreed, which is why neutral mutations and genetic drift do not lead to adaptation, but do provide lots of variations in the gene pool. The role for natural selection is to sort between the adaptive variations and the anti-adaptive ones in response to the prevailing ecology (while remaining neutral to the ones that are neither, allowing more genetic drift ...). The complete picture is even more complex as there are other processes that can step in and affect a population's ongoing evolution.
To get REAL evolution something has to be selected or isolated from among all those varieties and as soon as that happens, what I'm describing about the necessary loss of genetic diversity in this process has to occur.
To get REAL evolution (as the term is defined and used by biologists) you only need to have a change in the frequencies of hereditary traits in breeding populations from generation to generation in response to ecological possibilities.
To get speciation, all you need is isolated sub-populations living in different ecologies for those sub-populations to undergo different selection of different adaptive variations, until the point is reached that the daughter populations are no longer able to interbreed (either through behavioral mechanisms or through physical mechanisms).
To get diversity all you need is evolution and speciation and evolution and speciation and evolution and speciation ... etc etc etc.
You are now talking so much in the abstract that you are losing the context here. I'm trying to stick to what goes on in observed populations all the time in our own living reality. I'm being abstract too but at least my context is something going on in the present. You have to explain how this supposed surfeit of alleles relates to the usual processes of evolution under natural selection and genetic drift and so on.
No, Faith, this is what the hominid fossil record actually shows - several lineages diverging since that common ancestor with chimps, that each on their own represent a different genome. Many of these have been discarded through extinction and we still have 95 to 98% similarity with chimps.
We also have the example of Neanderthals, which share about the same proportion of their genomes with chimps and about the same proportion of their genomes with humans. Curious? Think of a triangle instead of a linear progression. Knowing this helps us define what genes were inherited from the common ancestor and which have been derived since then.
Message 82: Depends on how you are using the terms.
As long as I use the terms as they are used in biology then I am in agreement with how biology addresses the issue. If I used the terms some other way, then I would be discussing something else, which would be silly.
You can have A variety in the sense of a highly refined breed of dog or type of flower, and in the case of the dog it should exhibit reduced genetic variability with respect to the dog population as a whole.
And yet the dog can have as many alleles for the various genes as any other dogs in other breeds or in mutts. The population as a whole will always-always-always have more total alleles than any one individual.
Variety is about phenotypes, variability is about genotypes.
And yet you can have a variety of genotypes, if what you are talking about is variety within the population. Conversely if you are now talking about variety as a sub-category of species, then it is defined by the genetics of that variety.
The phenotype is the genotype expressed in the individuals. You can't have a phenotype in a population and any genotype from that population.
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


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This message is a reply to:
 Message 85 by Faith, posted 03-27-2010 4:07 PM Faith has not replied

  
Theodoric
Member
Posts: 9076
From: Northwest, WI, USA
Joined: 08-15-2005
Member Rating: 3.7


Message 141 of 851 (552749)
03-30-2010 10:20 PM
Reply to: Message 85 by Faith
03-27-2010 4:07 PM


Re: A new theory of evolution by mutation?
Human evolution from a supposed common ancestor with chimps couldn't have happened.
Here in a nutshell is where we see your whole issue.
Where has any person that understands evolution stated this? I have said before Faith that you need to learn the positions you are arguing before you post on them. If you got this from a source, they are lying to you.

Facts don't lie or have an agenda. Facts are just facts

This message is a reply to:
 Message 85 by Faith, posted 03-27-2010 4:07 PM Faith has not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 142 of 851 (552753)
03-30-2010 10:42 PM


pressure cooker relief time extended
I VERY much appreciate the posts in answer to my questions, thank you all very much, and I really wanted to get back to this thread but I am finding it hard to deal with some of the attitudes and pressures at this forum after all and need to prolong my break, not only from this thread but from EvC altogether. How long I don't know. Maybe only over night. Have to see where my frame of mind goes. I'll at least ponder your input while I'm away. The thread isn't going to disappear I assume.
Sorry, I really thought I'd be back soon to this thread.
(Theodoric that's a conclusion that follows from my observations -- which you would despise anyway of course -- not a premise or article belief I just picked up somewhere. )
Thanks again.
Edited by Faith, : add last thought

Replies to this message:
 Message 143 by Percy, posted 03-31-2010 7:22 AM Faith has replied

  
Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 143 of 851 (552802)
03-31-2010 7:22 AM
Reply to: Message 142 by Faith
03-30-2010 10:42 PM


Why Allele Subsets do not a Species Make
Hi Faith,
Take all the time away you need. In the meantime I'm going to attempt to describe why a unique species cannot form from an allele subset.
Assume a population has 26 genes labeled a-z.
Further assume that each gene has 4 alleles labeled a1-a4, b1-b4, and so forth.
An earthquake occurs that causes a river to change course, and a subpopulation becomes trapped on land that is now an island. This population only has the first two alleles of each gene, a1-a2, b1-b2, and so forth.
If this alone were sufficient for speciation, then you should be able to list a combination of specific alleles that could form in the subpopulation but not in the main population. How are you going to do that, given that every allele in the subpopulation exists in the main population? For example, try this one:
a1b2c1d2e1f2g1h2i1j2k1l2m1n2o1p2q1r2s1t2u1v2w1x2y1z2
There's not a single allele in that list that doesn't exist in the main population. No matter how you mix and match alleles in this subpopulation, it is impossible to come up with a combination that couldn't happen in the main population.
That's why allele reduction does not result in speciation.
--Percy

This message is a reply to:
 Message 142 by Faith, posted 03-30-2010 10:42 PM Faith has replied

Replies to this message:
 Message 393 by Faith, posted 04-17-2010 5:26 AM Percy has replied

  
Modulous
Member
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


(1)
Message 144 of 851 (552837)
03-31-2010 11:43 AM
Reply to: Message 124 by Faith
03-28-2010 2:54 PM


On variation and it's origins
Hi Faith, good to see you back in the ring - try not to let the mob wear you down
1) In domestic breeding -- let's stick to dogs -- do you agree that you get and maintain a breed by being sure you breed it with its own type?
First of all you find an existing dog that has as close to a desired characteristic as you can. Let's say you want a friendly breed, you find yourself a friendly dog. Then you find a friendly bitch that is as unrelated to the dog as possible. Then you interbreed them and hope that the things that make friendly dogs is passed onto the puppies from which the friendliest are selected and bred from etc.
Breeds are often created by a breeders particular desires, or by a chance characteristic being discovered, preserved and then exaggerated (such as with minature or dwarf cats with very short legs).
Then what tends to happen is that secondary traits might appear like a long tail. Characteristics are often linked like this, and not in obvious ways. For example: When scientists tried to tame foxes by breeding for friendliness, they found pretty 'doglike' coats forming (black and white spotty coats for example) even though they weren't specifically trying to create those coats. Turns out that the adrenaline biochemical pathways were being used by the melanin production side of things too. So by changing the genes that affect the pathway, they inadvertently messed around with the hair colours.
After that - often the best way to find a dog with all the characteristics of the breed you like, is to look within the breed.
2) Do you agree that this is to protect the breed's particular allele complement from contamination from alleles of other dog types?
More or less. I am not a dog breeder, or a geneticist - but this is my understanding of things, yes.
3) Do you agree that any dog breed possesses a very limited genetic diversity with respect to the total dog population
A more complex question.
By nature of being a subset - it is almost certain to be lower in diversity than the whole. But you might mean 'does a dog breed have a lower diversity than a similarly sized random selection of dogs', and I think the answer is - maybe but not by an enormous amount.
I suspect that if we only had the coding section of the genetic code to go on - it might take some time to identify a specific breed (barring computer intervention), so similar would it be to any other random dog.
4) Do you agree that it is its limited genetic diversity that is the basis for the characteristics of the breed itself and that if there is any increase in the genetic diversity the breed will lose its character at least to some extent?
There is no platonic Beagle.
There is only what people presently think are the characteristics required to be present or absent in order for a dog to qualify as being named a 'Beagle'.
Nevertheless - there is a hell of a lot of genetics going on that don't affect the Beagle characteristics of an animal. A dog could have a mutated cytochrome c gene, which would be an increase in genetic diversity but the animal and its puppies would still qualify as Beagles and nobody sane would think they had lost any Beagleness to any extent by the change.
Further - synonymous alleles could arise. Alleles act in the same way, but the genetic code for them is different. This would have no affect on said Beagle's nomenclatural status either.
I do agree that genetic change in the alleles responsible for 'core Beagleness' - is likely to make something less Beagley than more Beagley. But it might make a Beagle more pleasing to the eye, and lead to a change in what people call a 'true Beagle'.
But I disagree that genetic diversity within a breed is to be avoided. Breeder's tend to want as much genetic diversity in the Beagle population as possible while maintaining the traits they find pleasing.
5) Do you agree that Darwin based his natural selection on domestic selection?
Darwin used domestic selection as one of the evidences for evolutionary forces and proposed that the natural effects of more offspring dying than reproducing would have a similar outcome to domestic selection but instead of being adapted to the needs of the farmer, the needs of whatever environmental factors are most key to their reproductive success.
6) Do you agree that natural selection is the "engine of evolution?"
Natural selection is a requirement of adaptive evolution. Without it, adaptive evolution wouldn't happen.
7) Do you agree that the end goal of evolution is speciation or is evolution simply any change at all whether it ever leads to speciation or not?
Just change basically. Speciation is the result of things changing over large expanses of space and time, at different rates and to adapt to slightly different needs.

So two finches land on an island. There are 4 alleles max per gene. It's likely to be less. They reproduce until the island has 1,000 finches on it. Let's say no beak related mutations have occurred, and the beak alleles all do the same basic job. Further, let's say that natural selection of beaks only kicks in at 1,000 finches when a struggle for the resources of food comes in. Using their present beaks, the island can only support 1,000. Even if their beaks were just a little longer, the island could support 1,100.
You seem to be suggesting that if some alleles tend to be in finches that have short beaks (eg., that allele is involved in making shorter beaks), then natural selection will lower the frequency of that allele - potentially to the point of eradication and the eradication of an allele is a loss of diversity therefore natural selection doesn't create diversity and if the 'engine of evolution' can't create diversity then evolution can't explain diversity even though it claims it can! Furthermore, since evolution requires subpopulations to occur which involves a loss of genetic diversity - and a requirement for no further genetic input from the parent population - evolution requires that evolution can't account for genetic diversity!
But seriously, adaptive evolution (the kind of thing that explains eyes, hearts, legs etc) requires for their to be more that are born than survive to reproduce, for their to be variety from parent to offspring, for that variety to be heritable.
The variety from parent to offspring is in the form of mutations. If adaptive evolution is occurring on our hypothetical island, then there may well be new beak creating alleles popping up. Most of them will either create maladaptive beaks or have no affect. But any mutation on any gene that is even indirectly linked to the beak has the potential to do something useful like create a slightly longer narrower beak. An island filled with finches with that kind of beak might be able to support 1,100 finches! This is adaptive evolution, and it requires variety in the form of heritable mutations.
If this didn't occur, then you'd be right - evolution would simply be the dilution of a highly diverse parent population into ever more genetically sparse sub populations who just engage in recombination with one another. But it does occur, so you aren't right.
Or, as Darwin said:
quote:
Again, it may be asked, how is it that varieties, which I have called incipient species, become ultimately converted into good and distinct species, which in most cases obviously differ from each other far more than do the varieties of the same species? How do those groups of species, which constitute what are called distinct genera, and which differ from each other more than do the species of the same genus, arise? All these results, as we shall more fully see in the next chapter, follow inevitably from the struggle for life. Owing to this struggle for life, any variation, however slight and from whatever cause proceeding, if it be in any degree profitable to an individual of any species, in its infinitely complex relations to other organic beings and to external nature, will tend to the preservation of that individual, and will generally be inherited by its offspring. The offspring, also, will thus have a better chance of surviving, for, of the many individuals of any species which are periodically born, but a small number can survive. I have called this principle, by which each slight variation, if useful, is preserved, by the term of Natural Selection, in order to mark its relation to man's power of selection. We have seen that man by selection can certainly produce great results, and can adapt organic beings to his own uses, through the accumulation of slight but useful variations, given to him by the hand of Nature. But Natural Selection, as we shall hereafter see, is a power incessantly ready for action, and is as immeasurably superior to man's feeble efforts, as the works of Nature are to those of Art.

This message is a reply to:
 Message 124 by Faith, posted 03-28-2010 2:54 PM Faith has replied

Replies to this message:
 Message 145 by Faith, posted 04-01-2010 9:35 AM Modulous has seen this message but not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 145 of 851 (553046)
04-01-2010 9:35 AM
Reply to: Message 144 by Modulous
03-31-2010 11:43 AM


Re: On variation and it's origins
I think I've blown it. I think I'm going to be suspended. I'm going nuts here. I don't belong here.
I did want to deal with this thread. I'll deal with it on my blog alone but I did want to keep getting input. The problem is that I still believe what I started out believing, I believe there is a logical progression in what I'm saying, that all the objections raised to it seem to me to miss the point, and some of them are angry put downs of the sort I get wherever I put my opinions on this forum, which is very hard to take, and there's NO hope of getting anyone here to take anything I say seriously. I can pursue what YOU think to clarify things up to a point but the basics are going to stay the same and I don't want to keep writing into such fury.
I'm sorry I went to other threads. It's just got me furious at the basic attitudes here.
If I'm not suspended I'll still try to focus on this thread. Otherwise so long.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 144 by Modulous, posted 03-31-2010 11:43 AM Modulous has seen this message but not replied

Replies to this message:
 Message 146 by nwr, posted 04-01-2010 9:43 AM Faith has not replied
 Message 147 by Admin, posted 04-01-2010 10:00 AM Faith has replied
 Message 152 by Blue Jay, posted 04-01-2010 1:03 PM Faith has replied
 Message 157 by Capt Stormfield, posted 04-01-2010 4:48 PM Faith has not replied

  
nwr
Member
Posts: 6408
From: Geneva, Illinois
Joined: 08-08-2005
Member Rating: 5.1


Message 146 of 851 (553050)
04-01-2010 9:43 AM
Reply to: Message 145 by Faith
04-01-2010 9:35 AM


Re: On variation and it's origins
Faith writes:
I'll deal with it on my blog alone but I did want to keep getting input.
Can you post a link to your blog, or enter it in your profile as your home page. Thanks.
Faith writes:
I'm sorry I went to other threads.
I find it better to avoid the political threads, or at least to be very minimalistic about what I post there. Those threads usually generate far more heat than light.

This message is a reply to:
 Message 145 by Faith, posted 04-01-2010 9:35 AM Faith has not replied

  
Admin
Director
Posts: 12998
From: EvC Forum
Joined: 06-14-2002
Member Rating: 2.3


Message 147 of 851 (553062)
04-01-2010 10:00 AM
Reply to: Message 145 by Faith
04-01-2010 9:35 AM


Re: On variation and it's origins
You have a PM.

--Percy
EvC Forum Director

This message is a reply to:
 Message 145 by Faith, posted 04-01-2010 9:35 AM Faith has replied

Replies to this message:
 Message 148 by Faith, posted 04-01-2010 10:50 AM Admin has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 148 of 851 (553079)
04-01-2010 10:50 AM
Reply to: Message 147 by Admin
04-01-2010 10:00 AM


Re: On variation and it's origins
What's a PM?

This message is a reply to:
 Message 147 by Admin, posted 04-01-2010 10:00 AM Admin has replied

Replies to this message:
 Message 149 by Huntard, posted 04-01-2010 10:53 AM Faith has not replied
 Message 150 by Admin, posted 04-01-2010 10:54 AM Faith has replied

  
Huntard
Member (Idle past 2295 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 149 of 851 (553080)
04-01-2010 10:53 AM
Reply to: Message 148 by Faith
04-01-2010 10:50 AM


Re: On variation and it's origins
Faith writes:
What's a PM?
A Private Message. Look at the top right of the page, you'll see the word "Messaging" there should be a number beside it and it should be blinking. It's a new feature Percy recently installed. He sent you a message, and I'm guessing he wants you to read it.

This message is a reply to:
 Message 148 by Faith, posted 04-01-2010 10:50 AM Faith has not replied

  
Admin
Director
Posts: 12998
From: EvC Forum
Joined: 06-14-2002
Member Rating: 2.3


Message 150 of 851 (553082)
04-01-2010 10:54 AM
Reply to: Message 148 by Faith
04-01-2010 10:50 AM


Re: On variation and it's origins
At the right end of the line of links at the top of the page is one that says "Messaging(1)". The "1" means you have 1 private message that you haven't read yet. Click on the link and you'll be taken to the Inbox of your personal private messaging page.

--Percy
EvC Forum Director

This message is a reply to:
 Message 148 by Faith, posted 04-01-2010 10:50 AM Faith has replied

Replies to this message:
 Message 151 by Faith, posted 04-01-2010 10:57 AM Admin has seen this message but not replied

  
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