[Taxacom] quote of the week

John Grehan jgrehan at sciencebuff.org
Thu Mar 20 11:53:48 CDT 2008

> From: Pierre Deleporte [mailto:pierre.deleporte at univ-rennes1.fr]
> - that a model is "mathematical" or verbal makes no difference, the
> mathematical model is simply more precise,

If something does not exist in nature then I don't see it being very
precise - moth or no math.

> - now, did you really check how much molecular evidence in favor of
> (Human-Chimp) is gap-free, hence without alignment problems at all ?

This is something that has been on my mind and I would like to look into
sometime in the not too distant future.

> - and please note that many molecularists do not make use of
> aligned chunks of sequences, 


> - would you try and analyse the gap-free molecular data, a correlate
> that you should logically expect seeing (Human-Orang) pop up from this
> analysis - and if not, you should be ready to aknowledge this as a
> argument against your pet scenario, according to your own asserted
> principles

Alignment is only one problem. The other is whether the four alternative
sequences are cladistically comparable to morphology. What sequences are
really derived is something that I think is not really understood. For
example, where is the unique sequence coding that does along with the
unique ear structure?

> - besides this, your previous argument "I'm alone, hence I'm supposed
> be wrong" is not fair play at all;

You took the bait. That was irony on my part. The fact is that most
biologists seem to take the view that the orangutan theory is wrong
because most biologists hold that view. Bad science I know.

> - and as for "laws of great numbers" (which has strictly no particular
> link with phenetics, by the way),

Yes it does - in my opinion.

> are you ready to renounce insisting that you have 30 morphological
> arguments rather than a couple of them?

Only if they are apomorphies. There is a widespread argument by
molecular biologists that they are more likely right because they have
lots and lots of characters to look at.

> why are you insisting on "30" at all? if great numbers really don't
> count in phylogeny inference...

They matter if they are apomorphies.

> - trying to endorse your point of view, I would suggest:
> - don't insist on "30", e.g. just count one for morphology, and one
> molecules (but don't you also count morphological arguments against
> another?...)

As said before, I think comparing sequences to biological features is
like comparing apples and oranges. One is cladistic, the other is not.

> the point is that you can't convince anybody if you don't demonstrate
> flaw in the molecular analyses of primates, 

Have done so, only others don't accept them as flaws. And why not the
other way around? - no molecularist has ever demonstrated a flaw in the
morphological analysis of primates. They just assume so.

> still not a question of number of members in the club: simply, this
> argument file of yours is presently empty...



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