[Taxacom] morphology and molecules again

[John Grehan]

Comments inserted below.

________________________________

From: Jason Mate [mailto:jfmate at hotmail.com] 
Sent: Thursday, August 13, 2009 9:58 AM
To: John Grehan
Subject: RE: [Taxacom] morphology and molecules again

 

Dear John,

other than congruence between and within datasets, there is no other
impartial, objective criterion to judge data. 

Perhaps, but congruence or incongruence does not provide any judgment
other than two data sets agree or don't.

What's more I would even argue that internal congruence (i.e. homoplasy
in all its measurements) is unreliable to judge the quality of the data.
In the end if you don't assess or compare your inferences with the
larger body of knowledge then your only guidance would be intuition or a
time machine.

On might compare one's data (or results of the data analysis) with other
insights, but that does not presuppose subordination of one's data at
the outset.


You mention that congruence in itself is uninformative, but in regards
to what? 

In regards to anything

You also mention ''total congruence'' so I am guessing that it would
have to fit unavailable data that may be found later? 

No, meaning parts of a phylogeny might match while others do not.

If two different datasets analysed in different ways by different people
result in a similar topology, my confidence in that topology's ability
to summarise the evolutionary history of those taxa is bolstered. 

At the very least there is no apparent anomaly.

Yes, more data may prove it wrong in the future but that is true about
anything. 

Agreed - but not arguing about that

I am only arguing that the hypothesis (the phylogeny) is the best
current explanation for the available data.

Agreed, but again, I'm not arguing about that principle.


The angle of the authors is not hinting at kow-towing, it is more a
defensive position based on a question posed by somebody. Of course the
whole incident might be apocryphal but it still reads as a defence of
morphology vs genes.

You are right, they are not hinting, they are actually explicit about
kow-towing as quoted in my email.

One of my paragraphs was cut midsentence. In a nutshell Homo's placement
is of little interest to me so I will not dwell there.

No worries, but the anomaly between morphological and molecular evidence
for hominid evolution should be of general interest as a general
problem.


John Grehan

Best

Jason

________________________________

What can you do with the new Windows Live? Find out
<http://www.microsoft.com/windows/windowslive/default.aspx>