Re: Evolution Archive List
Sun, 30 May 1999 14:41:57 EDT

I hope "Huxter" doesn't mind my jumping in like this. I owe him for
misrepresenting his statement regarding molecular clocks.

In a message dated 5/30/99 11:42:44 AM Mountain Daylight Time, writes:

> Bertvan:
> I hope you are not a scientist. I would hate to think most scientists
> regard such deceit as common practice. I would hope those willing to use
> fraud are very, very rare-- including those scientists whose conclusions I
> disagree with.

I am a scientist and it is not deceit to use old information if there is no
other information available. Since all information presented must be cited
with a reference, anyone reading a paper will see how old the information
actually is and so will not be deceived. What is deceptive is to present old
information and neglect to mention that there is newer information that
overrules the old information. I find that many creationists tend to do
this, but no legitimate scientist will.

> Bertvan:
> Could you explain in more detail how Natural Selection works on non-coding
> regions of DNA?

Natural selection and genetic drift are two separate mechanisms. Non-coding
regions by definition are exempt from natural selection, but genetic drift
can still cause them to evolve by the accumulation of mutations.

> Natural selection allows the survival of those traits which
> allow tho organism to produce the most survivable offspring, right? How
> could non-coding DNA contribute to the "fitness" of the organism, and
> therefore be "selected"?

You are confusing evolution with natural selection. Natural selection
(selection of the most fit) is only one possible mechanism for evolution.
Genetic drift can also produce evolution without selecting for fit traits or
against unfit traits.

> Bertvan:
> Some non-coding DNA specify protein products? How is it determined which
> protein products they specify?

No, you misunderstood him. He was defining non-coding regions as being
regions of the DNA that do not specify any protein product. He then stated
that some of these regions can bind proteins. He was not saying that some
non-coding regions can specify protein products.

> Other non-coding DNA provide binding sites?
> How do they do that if they are not expressed?

The proteins that bind to the non-coding DNA regions recognize specific
nucleotide sequences; the DNA itself does not have to express any kind of
protein for another protein to bind to it.

> Bertvan:
> By information I meant coding for proteins or gene regulation. But you've
> already answered that by explaining that non-coding DNA does code for
> proteins and provide binding spots. Thank you for your patience.

Information can also be a DNA nucleotide sequence even if it doesn't express
any kind of protein.

Kevin L. O'Brien