Evolutionary mechanism for diversification

[scott_alexsk]

I read an interesting article in the national geographic which stated that a possible mechanism for diversification in evolution might be inside organisms themselves. The article stated that there was an anomoly in the diversity of a selectly breeded chicken population. With the selective breeding all diversity should have been eliminated. However it remained. Does anyone else know anything about this?

Thanks,
-scott

 

[muadib2k]

I'm not 100% sure that I understood your post correctly, but here's my take on it. When you selectively breed animals you usually do so for a certain trait or a group of traits, but there are be numerous other genes (traits) that are excluded from your breeding selection. Because of that you will not eliminate the diversity in those traits, which may contribute to the overall diversity in a population. Not sure if this is what you were talking about, but hopefuly it helps.

 

[MemoryOfUs]

Survival of polymorphisms symbolizes the diversity of the morph itself.
Anomaly represents the result of original contradictions and the best fitness obtained for self in current environment.
And no, i don't know anything about your article but I suppose I am not going to limit myself in words or specific definitions or that would harden my realization of what I should believe...

 

[quantumcarl]

Survival of polymorphisms symbolizes the diversity of the morph itself.
Anomaly represents the result of original contradictions and the best fitness obtained for self in current environment.
And no, i don't know anything about your article but I suppose I am not going to limit myself in words or specific definitions or that would harden my realization of what I should believe...

Sorry, I just know some cytogeneticists and some pathologists who will tell you that the frequency of gene interaction is out of scale and numerous and that to think that the blundering thumbs of human intervention can mimic that complexity of synergy is a whack way to think. Totally whack. Its an attempt to cram a few billion years of evolution into a decade or so. And its a faulty undertaking that results in collapse.

 

[MemoryOfUs]

I just do take it for granted that biology alone would never be enough to give explanation to the origin of life on earth.

 

[PIT2]

I read an interesting article in the national geographic which stated that a possible mechanism for diversification in evolution might be inside organisms themselves.

Here is something i read awhile ago and which also talked of an internal cause of non-randomness.

Yampolsky and Stoltzfus argue that in a more general theory, mutation-biased evolution does not have to be neutral.

Stoltzfus says that many of Darwin's 20th century followers adopted the view that all non-randomness in evolution comes from natural selection. "What is important, then, is to use population-genetic reasoning to demonstrate that both mutation biases and selection influence the outcome of evolution under simple conditions. Without disputing that natural selection is a prominent 'external' cause of non-randomness in evolution, we maintain that there is also an 'internal' cause arising from biases in variation. It is this kind of 'internal' directionality- disparaged by 20th century Darwinians as 'orthogenesis'- that is needed to fully appreciate modern research in molecular evolution and in evolutionary developmental biology."
http://www.sciencedaily.com/releases/2001/03/010313074117.htm

 

[selfAdjoint]

Sorry, I just know some cytogeneticists and some pathologists who will tell you that the frequency of gene interaction is out of scale and numerous and that to think that the blundering thumbs of human intervention can mimic that complexity of synergy is a whack way to think. Totally whack. Its an attempt to cram a few billion years of evolution into a decade or so. And its a faulty undertaking that results in collapse.

I certainly believe that Lamarkism, inheritance of acquired traits, has been well eliminated by decades of results. But a mother's nutrition could well effect, even determine, the expression of her offspring's genes in that one successor generation, given the understanding we are now getting about the complexity of the gene expression process and the importance of expression in determing how the genes build the phenotype.

 

[scott_alexsk]

Thank you all for your posts.

In the article the breeder stated that they should have run out of unwanted diversity by a certain point. However despite their selective breeding for favorable characteristics they still had unfavorable ones.

I have a tendency to think that they were breeding for dominate characteristics rather than ones which are usually recessive, since they made such a big deal about the unexpected diversity of the chicken population.

This means to me that they may have had a situation in which both parents had only fully dominate and favorable genes, or apparently, and their offspring had a unfavorable characteristic from a recessive gene, which seemingly came out of nowhere.

Is it possible, with the knowledge that science has now, to remove known recessive genes?

 

[scott_alexsk]

Is it possible that more than one gene is passed from each parent, which could be found unexpressed in the ton of 'junk' DNA that most organisms have?
-scott

 

[quantumcarl]

I certainly believe that Lamarkism, inheritance of acquired traits, has been well eliminated by decades of results. But a mother's nutrition could well effect, even determine, the expression of her offspring's genes in that one successor generation, given the understanding we are now getting about the complexity of the gene expression process and the importance of expression in determing how the genes build the phenotype.

I agree that nutrition plays a huge role in gene expression. I'm only pointing out that one gene is really only operative with the support of an unknown number of others... and their half twins!

Remember that every gene has its own DNA, and then some. This reminds me that genes may well be a species of algae or something that started banding together and forming chromosomes. Thanks@