Comments on Niamh Middleton on Evolution

some will probably disagree:

Some, perhaps. But the authors of those two papers don’t seem to have anything to say on that subject. This is just more evidence that you don’t read the papers you cite or do read but don’t understand. You have, for example, confused neutral evolution with drift; not the same thing.

" The first such studies were carried out in Drosophila melanogaster and D. simulans , finding that ∼50% of all amino acid substitutions have been fixed by positive selection".

So? We were talking about humans, and we were talking about the entire genome. Have you already forgotten about junk DNA?

I didn’t speak about the entire genome. I am not a geneticist. And yes I know what junk dna is. Don’t get your point

Oh you weren’t speaking to me

true, but i remind you that neutral mutations should also take place in coding genes.

So what? You seem to believe that’s the same as saying that all mutations in coding genes must be neutral. It isn’t.

not all but most of them. dont you agree?

No. Even your source refers only to non-silent mutations.

so are you saying that the majority of changes in coding genes between the species is the result of natural selection or neutral mutations?

Too vague a contention to reply to. Between what species? What changes? I would suggest that silent changes are almost all neutral or close to it, and that many of the non-silent changes that become fixed are too. The great majority of selection in coding sequences is purifying. Between humans and chimps, coding sequences are about 99.5% identical, while junk sequences are only about 98.7%.

Gosh! If there is no consensus among evolutionary biologists, does that mean that there is (gasp!) debate among them over these questions?

Geologists debate the fine points of geology, but that doesn’t mean a Flat Earth is a viable scientific position.


You don’t understand the target of my remarks. John Mercer is endlessly saying “there are no debates in science”, “scientists don’t debate things; they only look at evidence” and the like. But as far any normal reader of English can tell, from the normal use of the word “debate” in English, there are debates among evolutionary biologists regarding the relative weighting of mechanisms, how much each contributes to evolutionary results.

It’s my observation that Mercer is the only scientist here who insists that “debate” should never be used to describe the way scientists discuss their differences. So my remark was aimed only at him. It’s pretty clear the evolutionary biologists have debates (i.e., thrashing out disagreements) over evolutionary mechanisms.

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It’s a reduction of variation when an allele becomes fixed, but before that it has to pass from a frequency of 1/(2Ne) to a frequency of 1 and passes through all the intermediate frequencies. The alleles currently at intermediate frequencies are the ones that contribute to variation. If purifying selection worked on all alleles there would be very few alleles at intermediate frequencies.

I think we are all sensitive to how debates have been misconstrued and misrepresented by those who have no real interest in furthering scientific knowledge.


Quotes please.

Quotes please. Or a retraction and apology. What I actually do say is, “Scientific questions aren’t decided by debates.” Even you can see the difference between that and your fabricated quotes, which are as true as your claim that peptidyl transferase is a protein.

Quotation marks are used for actual quotes. Do you have any that match the ones you are attributing to me?

The normal use of the word “debate” in evolutionary denialism refers to two people standing behind podia and taking turns arguing. When was the last one of those in biology? Surely your ID brain trust, with whom you allegedly regularly discuss nonexistent “ID theory,” could find them.

Is it the same as non-coding DNA in your opinion?