Discussion of everything related to the Theory of Evolution.
Tomn, may you allow me a general question? What is the point in discussing Evolution in a scientific forum, if you dont accept scientific explanations?
http://en.wikipedia.org/wiki/Evidence_of_common_descent (Best of)
Btw, this discussion reminds me of that one:
WW: Show me the evidence!
RD: There it is!
WW: Yes, but where`s the evidence?!
-- REPEAT MANY TIMES --
WW and RD. A very cool joke. Honestly, you guys just paint things in nature as evidence.
For example, I am sure you know of the dark moths/light moths in Europe. It is said by evolutionists that before smog, trees where light-colored and thus hid the white moths, and black moths were easily eaten. Then, post-smog production, the trees got darker, and the reverse effect occurred. I am not debating that this happened.
What I do debate is the fact that evolution states that these two different genes occur as a result of mutations, which is the engine of evolution. My protest is: How do you know that this is a mutation?
And the response that I get is that:The mutation occurred in a time before we knew how to identify mutations in genes.
Then my rebuttal is: If the mutation occurred in a time when we did not know how to identify mutations, then how can you call the different genes in moths a mutation? Where is your proof that this is a mutation?
And to this, I get no response or admission that the theory of evolution is a fraud.
Other than evidence, the different gene is just something evolutionists painted over it just because it proved the theory.
If you could clarify the evidence showing that the moth gene is a mutation, or how it is called a mutation, I would appreciate it.
-facts, observed events, plausible explanations, and solid evidence
This is going to be a long post. It's not for Tomm's benefit, because he knows that science exists to deceive (it's funny that his computer seems to work just fine). Maybe someone else is interested in this moth stuff.
First, some basic genetics. As a geneticist, I like to make the distinction between "mutation" and "polymorphism". For the uninitiated, polymorphism literally (from the Greek) means "many forms". A mutational event creates a polymorphism. So calling all polymorphisms mutations is not very accurate, because we do not always know which form was ancestral and which form came from a mutational event. I know, it's nitpicky, but science has to be nitpicky. Genes contain polymorphisms that have arisen by mutational events that have occurred throughout the evolutionary history of the gene. Each different version of a gene (has a unique set of polymorphisms) is called an allele. In diploid organisms like us humans, each individual can have a maximum of two alleles for each gene, one from our mother and one from our father. Within a species or even a population, though, there may be hundreds or thousands of different alleles for any particular gene (maybe not for us humans, but some species possess incredible amounts of genetic variation). New alleles are being created all the time by new mutational events (even normal recombination during meiosis can create new alleles if the cross-over occurs within a gene), so some alleles within a population will be new and some will be old, having been created hundreds or thousands or hundreds of thousands of years ago.
OK, now to moths. Most of the confusion here, in my opinion, is due to the misconceptions concerning the use of this nasty word "mutation". A scientist will say, "The melanism is due to a mutation". Most people will hear, "A mutation has caused the melanism". So, most people think that, as the pollution grew worse and all the light-coloured moths were getting eaten, a new mutation occurred that made moths darker and saved the day. For all I know, this did occur, but it probably didn't. Because lots of variation between individuals exists within populations, the population will have always had both light and dark individuals - the gene(s) controlling colour had many different alleles within the population. Before the pollution, the dark forms were rare in the population because they got eaten more and therefore reproduced less. After the pollution, the frequency of the dark forms increased within the population because they were eaten less and reproduced more. The allele (more likely a family of similar, related alleles) that is responsible for the dark form may have first appeared in the population a hundred thousand years ago and has been maintained in the population at a very low frequency ever since. So, yes, a mutation caused the melanism, but it probably wasn't new, so the melanism probably wasn't new. The high frequency of melanism in the population was the result of selection for the dark form. This is what natural selection is, and what evolution does over long periods of time. Descent (heredity) with modification (variation) and differential success (survival and reproduction).
Either that or some god did it.
Just to be clear: you are saying that the term "polymorphism" refers to the genes or alleles - as contrasted with calling the aggregate of the different or "many forms" of a character, the particular differing phenotypes, as the "polymorphism". Is that what you are saying ?
My apologies, Crucible, for creating this confusion. I've worked with DNA for so long that I forget that many non-geneticists think of mutations as the manifestations of changes in the DNA, which can also be called a polymorphism. Polymorphism, in the context being used here, though, refers to "many forms" of the DNA - it refers to the genotype. It's the change in the DNA that can then, or not, lead to a change in a character or phenotype. A change of one base for another is the most common (a "SNP" or Single Nucleotide Ploymorphism, also known as a point mutation). Deletions, insertions, and inversions also lead to changes in the DNA sequence of a gene (mutations can also involve larger chunks of DNA containing entire genes). Let's say that gene A has no variation at all in a population. Every individual in the population will have two copies of the same allele. One day a mutation occurs in gene A that creates a polymorphism in the DNA. A new allele has thus been created in gene A so that there are now two alleles of gene A in the population.
Does this clarify the situation?
Fully agree that is must be picky. So we have a distinction being offered between morphs - between alleles.The original allele vs. the mutant allele(s).
I would try to phrase it differently. Maybe to indicate the difference between a state where a gene has more than one form, and the various forms themselves.
If I get fatally run over by a bus, at age 10, did evolution occur ? If getting run over later in life, after having one child ? Two ? After grandchildren ?
How would we (theoretically ) determine whether or not evolution occurred ?
I think it's due to usage of words that have multiple meanings, and the user switching back and forth. It should be understood that different definitions apply in different fields, but in the same paragraph ?
Once we get to talking about Repressor Dawkins, we have a full blown activist and major word-weasel who takes things into the non-scientific realm.
Of course they will ! But wait ...
Precisely. That is the story we were all told.
Yes, it might have or might not have.
Were dark versions ever seen previously ? The answer seems to be yes, there was a dark morph.
There exists other possibilities other than mutation of a gene - whether it's a fresh mutation or old.
Or something else. You've made an unjustified leap in putting it down to a mutation causing melanism ( either old or new ).
Nevertheless, it's to be considered evolution, if it is melanism caused by mutation (either old or new), when the allele becomes more common ...correct ?
Last edited by Crucible on Tue Nov 08, 2011 6:19 pm, edited 1 time in total.
Let's take a quick look into how Repressor Jerry Coyne might or might not have shot himself in the foot over this supposedly mothballed subject.
I agree that loci can be referred to as being polymorphic if they contain polymorphisms - ie. the loci possess "many forms". The word "polymorphism", unfortunately for our discussion, does not have a tightly prescribed definition in biology. One of its meanings refers to "the actual things" whether we like it or not. Similarly, "mutation" can refer to the actual thing in the DNA or to the phenotypic expression of the actual thing in the DNA. A point mutation can be referred to as a polymorphism when talking about DNA sequences. An allele can be referred to as a polymorphism when talking about genes. Cells, tissues, organs, individuals, populations, etc. can all be considered polymorphic.
Your genes, from you, will have no influence on the future of humanity once they are removed from the gene pool (I'm restricting the word "influence" here to YOUR genes - even if you didn't reproduce, you could easily influence the future of humanity that could lead to genetic changes in the population). If your grandchildren fail to reproduce, the genes they got from you will come to a dead end. But your genes - actually, we should be talking about your alleles here since everyone has the same genes - your alleles, then, are not unique to you unless a new mutation has appeared in your germline. Most alleles within a population are shared by many people. It's the combination of alleles that make us all individuals. Since evolution involves the change in allele frequencies in populations over time, YOUR genetic contribution will end when YOUR alleles fail to get passed along to future generations.
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