Evolution of mutation!

Most all mutations are neutral mutations that simply collect in the genome and make up a large part of it.
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Yeah.
That's what I said.
And contradicts with what you said earlier.

True to form, Valich.
True to form.
 
Sorry I posted this on the 'Do Bacteria Communicate' thread but strangely it is equally applicable in both - some kind of polymorphism?

I would also refer to the American Fire Ant Solenopsis invicta, a colony is described by Wilson (2001) as: "an assembly of workers so tightly knit around the mother queen as to act as a single, well-coordinated entity."
The expressed products of the Gp-9 gene act as a mechanism in the control pathways of social behaviour affecting the level of colony queen:worker ratio (Ridley 2001). A female ant either becomes a queen, soldier or worker depending on the food and chemical stimuli received as a larva; however sometimes alates are produced that fly off to start new colonies.

I introduce this to enquire if there are similar mechanism in bacteria, and if so, whether the equivalent of 'alates' are produced.

I guess I'm looking at the idea that in a stable environment without mutation evolution would continue through polymorphism and allometry and the establishment of new populations.
 
Polymorph: Poly means "many," morph, as in morphology, means the shape and appearance of an organism. In other words, it is the phenotype expression of the genotype. The only way that new morphs can arise is through an alteration or change in the genotype.

Allometry refers to the disproportionate change in body size compared to an individual component or feature, such as a limb size or heart rate, etc. Normally this refers to comparisons made in developmental biology.

New populations arise on their own without any need for mutations, new polymorphs that arise from mutations, or allometry.

Evolution is a process. Polymorphisms are states of being. Allometry refers to disproportionate developments. What are you trying to say?
 
If in our hypothetical OP ecological system there is no mutation due to a gene would it be possible that through polymorphism 'alates' would create new populations?

Also I would describe: evolution as the regenerative and dynamic momentum of genetic information through space and time; polymorphisms as the existence within a species of different forms of individuals or the occurrence of different forms of the same individual at different times of life; and allometry as the study of relative growth, or disproportion in size relative to standard growth.
 
Again, you first talk as if polymorphism is a process, then state that it is an existence of different forms at different times. yes, this is why it is so commonly used in developmental biology. That's contradictory. And then: "Regenerative and dynamic momentum of genetic information"? Did you get this from the aliens landing at Area 54?
 
valich said:
Again, you first talk as if polymorphism is a process, then state that it is an existence of different forms at different times. yes, this is why it is so commonly used in developmental biology. That's contradictory. And then: "Regenerative and dynamic momentum of genetic information"? Did you get this from the aliens landing at Area 54?
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No - I perceive the movement of information moving through space and time in the form of genes and their material expression. Ditto memes - although in this instance information is moving through space and time in the form of culture. 'Reproduction' of information is achieved biologically and culturally; this is a dynamic process with momentum.
Its not from Area54 but is a basis for understanding evolution that I have developed myself from meta-analysis of the leading thinkers in the field. I'm just being honest - I could be picky about your definitions too...where did they come from? Area Wikipedia?

Regarding polymorphism: the reference is in Henderson's Biological Dictionary. I don't recognise the contradiction you suggest.
In the hypothetical OP: alates, allometric variants of polymorphism, are phenotypically-expressed due to a steady environment. This is important as as alates (or their equivalents should they exist) leave the parent population to start new populations.
If a 'terminator' gene stops mutation then maybe evolution will continue along another vector...I think I'm making reasonable points in a forum debate about an unprecedented hypothetical scenario.
 
What are "allometric variations of polymorphism" and how do they occur? I already told you what the standard definition of allometry is. And a polymorphism is a variant trait that already exists in a population, caused by the different alleles within the population. Some are advantageous: some are deleterious. Whether one polymorph becomes more dominant than another depends on the environmental pressures that select for it. This is not evolution: this is a change in allele frequency. This is a very basic standard definition accepted throughout the field of biology by everyone that you cannot change. Else you cannot communicate.

Mutations can occur during allometry that can change the phenotype. There are genes that express the phenotype; and also genes that regulate the developmental expression of the phenotype. This is why morphology is conserved in embryo replication amongst various heirarchical species in the phylum: genetic conservation within the genome.
 
the terminology being used is non-standard, but if I've been reading the posts right, he's extending the normal terms to work through a time-line as well as within a temporal snapshot of a given population.

So I've been interpreting the posts as "looking at the progression of different traits both within a population and over time." this seems to include not only a single population, but also the branch-off that occur when individuals take thier oddities to a new group, or start a new group themselves.

zenbabelfish, tell me if I'm mis-representing your position.

http://en.wikipedia.org/wiki/Allometry
http://en.wikipedia.org/wiki/Polymorphism_(biology)
 
the terminology being used "here" is non-standard. We talk about polymorphs over an extended time-line until those characteristics evolve into a different form resulting in a genetic change, by mutations or cross-overs. Black hair today was black hair 50 million years ago. Evolution does not progress through blending like taking a crayon and rubbing it darker. There has to be a genetic change that changes the genotype to express the different new phenotype. The article that you are citing on Wikipedia is one that I wrote.
 
valich said:
This is not evolution: this is a change in allele frequency.
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Evolution is defined, rightly or wrongly, as a change in allele frequency, you great lump of mutton.

vallich said:
The article that you are citing on Wikipedia is one that I wrote.
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Then it should contain a very large warning sign. If you don't even know how to define evolution you have no business on this site pontificating as if you were learned in the matters.
You arrogance remains only outpaced by your gross ignorance. A deadly combination.
 
I view a quality definition of evolution to be somewhat akin to a definition of life: a potentially valuable, but thus far unattainable goal. But like life I know what evolution is when I see it.
And where I saw it, in detail and delight, was in the fossil record. Since you can't see alleles in a fossil, for me evolution is about changes in form. Sure these reflect genotype, but they are not genotype.
So my working definition of evolution is 'change in the character of a population that likely reflects a change in genotype'.
 
One definition of evolution that is commonly used today is simply a change in allele frequency in a population. However, I do not care for this definition because it does not lead to new speciation. In the classic example with peppered moths in England, the allele frequency caused adaptation for black wings against the pollution but the allele frequency was reverted back to lighter gray-colored wings as is seen today. The end result: no change. No evolution. Allele frequency change alone, i.e., various polymorphs, does not result in evolution.
 
Ophiolite said:
I view a quality definition of evolution to be somewhat akin to a definition of life: a potentially valuable, but thus far unattainable goal. But like life I know what evolution is when I see it.
And where I saw it, in detail and delight, was in the fossil record. Since you can't see alleles in a fossil, for me evolution is about changes in form. Sure these reflect genotype, but they are not genotype.
So my working definition of evolution is 'change in the character of a population that likely reflects a change in genotype'.
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I'm terribly biased towards change of form myself. That's because I am a developmental biologist. Nothing makes sense to me but change of forms. Of course I have to keep in mind some of the physiological changes that are also present in evolution but don't manifest themselves in 'visible' form. And there is evolution of behaviour of course, but form is the king.

long live the king of evolution.
 
valich: please see my post from page one of this thread, and come up with a different example.

http://www.sciforums.com/showpost.php?p=1281023&postcount=16


Change in allele frequency in a population certainly can lead to speciation. If a population splits due to geographical or other reasons, the net genetic change between the to groups can lead to speciation - this has been seen in the lab, and has been seen in nature. Introduction of new mutations allows the "change in allele frequency" to not only be limited to shifts within the genetic pool, but to wholsale phenotype changes.
 
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Your rationale is not clear and is unarticulated. Your allusion to mutations is confusing because allele frequency can and does change without mutations. Miniature Fox Terriers, Pinschers and Schnauzers are smaller than their standard-sized breeds, and Pomeranians come in black, blue, tan, chocolate, chocolate, cream, orange, red and sable - all caused by different alleles, not mutations. They're still the same species. Where does allele frequency alone lead to new species where they can no longer interbreed?

Majerus concludes, reasonably, that all we can deduce from this story is that it is a case of rapid evolution, probably involving pollution and bird predation...claiming that the true story is likely to be more complex and therefore more interesting.

What can one make of all this? Majerus concludes with the usual call for more research...There are many studies more appropriate for use in the classroom, including the classic work of Peter and Rosemary Grant on beak-size evolution in Galapagos finches.
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valich said:
Your rationale is not clear and is unarticulated. Your allusion to mutations is confusing because allele frequency can and does change without mutations. Miniature Fox Terriers, Pinschers and Schnauzers are smaller than their standard-sized breeds, and Pomeranians come in black, blue, tan, chocolate, chocolate, cream, orange, red and sable - all caused by different alleles, not mutations. They're still the same species. Where does allele frequency alone lead to new species where they can no longer interbreed?
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Don't be so obtuse. Nowhere in river-wind's post did he state that a change in allele frequency alone lead to speciation.

Mutation leads to different alleles. Different alleles change allelic frequency. If an allele doesn't mutate, how does it change?
 
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