Re: Reduced Consensus (Was: Afrotheria revisited)

[David Marjanovic <david.marjanovic@gmx.at>]

----- Original Message ----- 
From: "Mike Taylor" <mike@indexdata.com>
Sent: Friday, March 23, 2007 6:06 PM

> And because everyone uses unweighted characters, something as
> gross as this difference in cervical morphology is worth no more
> than, say an unobtrustive process on the lateral face of the
> distal part of pedal phalange II-2.  I tell you, it's a sick
> world out there.

This argument certainly has to be taken seriously, but it has its limits. 
Eike recently told us about some birds where it turned out that there was a 
lot of phylogenetic signal in the colour of the animals, while beak shape 
converges and reverses as it pleases. It's not easy to guess a priori which 
features are favoured by stabilising selection.

Then there's reweighting (aka a posteriori weighting). I like its effects on 
my (ancient, tiny) bird analysis: without it I got *Patagopteryx* around the 
base of Euornithes -- probably due to a few features that may well be due to 
its flightlessness and may therefore not have been present in all of its 
ancestors --, while after reweighting it jumped closer to the crown than 
*Yixianornis*, IIRC. While partially circular, it's much easier to defend 
than a priori weighting.

BTW, the singular is "phalanx"... though originally it referred to all 
digits as a whole, the meaning of the Greek word being "army (hoplites lined 
up in rows)".