[Taxacom] Molecules vs Morphology‏

[Jason Mate]

> Furthermore, don´t
> > you think that the term, false, implies knowledge of historical truth
> > that, by definition, is probably unknowable?
> 
> Yes, but it was not me making these assertions!

OK, third attempt, why do you speak of false and true instead of congruent and incongruent? Do you have access to the truth?

> > No, no, no, don´t look into (o through) the Orangutan´s eyes! If your
> > results are not falsified by molecular datasets is the reverse also true?
> 
> Correct!!
> 
> > Because if it is then there is nothing to compare. 
> 
> ????

Do your results have no bearing upon the relationships of Homo, Pan & Co.?
If it neither supports nor contradicts, one must ask, is there any phylogenetic signal?

> Not to mention
> > that such fossil is just novel data and as such supports my position: if
> > in doubt get more data.
> 
> It certainly never hurts. But to show how tricky that can be, there were some worn teeth dated at 10 Ma that were said to be gorilla related because they fell into that size range, but had other features that did not conform to the gorilla, but to the orangutan and its fossil relatives. It is as if one possibility could not be considered.
> 
> But yes, new fossil material has the potential to stir things up. There are isolated fossil teeth labeled hominid (australopith) even though they resemble none of the embedded teeth in known hominids. Because they are so late in the fossil record they are assumed to be hominid, even though they have orangutan like characteristics.

I was thinking more like a skull even if incomplete. Teeth only...

> > >Yes - if one is a pheneticist and rely on overall similarity through the
> > law of large numbers.
> > >If the law of large numbers is applied to morphology one will get a
> > human-African ape relationship every time,
> > >just as one might get a crocodile-lizard grouping every time.
> > 
> > Sigh, not fair to use the "molecular data is phenetics" card when pressed
> > into a corner. 
> 
> Not in a corner. Law of large numbers is promoted by molecular argument.
> 
> > the distinction is not there. A large number of characters is a large
> > number of characters. 
> 
> Yes, but a large number of similarities vs a large number of uniquely shard similarities are two different things.

John, more information is better than less information. Or do morphologists stop looking once they have found one character? Come on, stop seeing the conspiracy in every statement. Secondly, the title of "uniquely shared similarities" hints at, "I understand these characters but not those". A priori you shouldn´t determine which are and which are not uniquely shared. And as for unique, one of the reasons why morphology is less homoplasious than molecular data is simply the character selection process in the former. In the latter you can´t say "we dumped 80% of the variable positions because they were too variable". Also most mutations at the gene level are more or less neutral which helps when you reconstruct a phylogeny.

> > However, if I have 50 genes, both nuclear and
> > mitochondrial, and they point one way, and the morphological data is in
> > conflict... lets just say the morphological dataset
> > needs some explaining.

>Or viceversa

If you are objective, no.


Best  

Jason


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