My comment here is not addressed to SteveW, but to any reader of this thread with an open mind. If you wish to determine the truth or falsehood of the emboldened assertion then consult any textbook on genetics. You will find that the assertion is false. Of course one can imagine that tens of thousands of scientists, including atheists, agnostics, Christians, Buddhists, Hindus, Jews, Moslems and others, have decided to manipulate the data and engage in a massive conspiracy that has been maintained for half a century and more. Or one can accept that the data clearly indicate that most mutations are neutral, some are deleterious and some are beneficial - and which is which often depends on the environment in which they are expressed. The choice of which view you accept (accept, not believe) is up to you.
So if DNA have this incredible mechanism to repair cells so that it can rectify the errors made in copying how are they not a mistake and something that would contribute to the cell not performing at its optimal best. The fact that the DNA has this error rectifying mechanism that will detect even the smallest mistake in one letter instruction for building proteins shows how sensitive the process is in needing to get things right. It doesn't make sense that you can say that a mistake in this copying process of what was already good and needed is beneficial or even neutral. The fact they call it neutral isn't because its really neutral. Its because the error is so small that it has no effect on its own. But when accumulated these small errors will have an effect. Even the so called beneficial mutations will have a cost to fitness when added together.
Diminishing Returns Epistasis Among Beneficial Mutations Decelerates Adaptation
These results provide the first evidence that patterns of epistasis may differ for within-and between-gene interactions during adaptation and that diminishing returns
epistasis contributes to the consistent observation of decelerating fitness gains during adaptation.
The thing is any mutation is an error because it has changed what was already working and needed to be copied and passed on. To think that an error in the copying of what is suppose to be already good is the basis for all the amazing complexity and variety we see in life that has ever existed in the past and living today seems hard to believe. Its like taking 1000s of steps backwards to take one step forward.
Here is an educational site which explains what mutations do and the copying and rectifying process and as far as I can see there is no mention of mutations being positive or even neutral.
A mutation alters the gene message so that it no longer sends the correct information to the cells
It is important that the correct gene message is read in order for the correct protein to be built.
If the sequence of DNA letters in a gene is not able to be read in the correct way, the protein:
* May not be produced in the right amount
* May be produced in a form that will not function
* Is not produced at all.
TYPES OF MUTATIONS
a) Spelling changes in the code
Changing the spelling of a word in the message by substituting one letter with another is called a point mutation
DNA changes that cause a different amino acid to be included in the protein are called
missense changes.
DNA changes that cause an early stop message in the protein are called
nonsense changes.
b) Deletion of a code word
A mutation can also occur when part of the gene is ‘deleted’ from the genetic code. If this occurs, the message will be too short and therefore will not make the correct protein.
c) Insertion of a code word
An insertion mutation occurs when extra DNA is ‘inserted’ in to the genetic code. If this occurs, the message will be too long and therefore will not make the correct gene product or protein.
d) Repeated code words
Another type of gene mutation is called a
trinucleotide repeat where certain code words are repeated in a sequence more often than usual.
http://www.genetics.edu.au/Publications-and-Resources/Genetics-Fact-Sheets/FactSheetMutations
Mutations take place at the base pair level. A base pair here or there is going to make little difference overall in an organism except for the loss of genetic information in most cases. Mutations do not happen with high frequency and when they do they are generally detrimental on the order of 1,000 bad mutations to 1 beneficial mutation. In order for mutations to make much difference there need to be a number of them at one time. If it took just two base pairs to make a beneficial mutation then it would take 1,000 x 1,000 tries before only the two beneficial synergistic mutations happened together. Take into account the rarity of mutations, there is little likelihood that this is even going to happen.
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