Re: No more paedomorphosis

["Matthew Troutman" <m_troutman@hotmail.com>]

<< So _Rahonavis_ is higher up the avian tree than I first thought. This 
has an interesting implication: the dromaeosaurid foot, with its 
enlarged second-digit ungual, is beginning to look like an avian  
symplesiomorphy (secondarily lost in _Archaeopteryx_ and in avialan 
birds), not a dromaeosaurid and/or troodontid synapomorphy..>>

     If Rahonavis is the most basal avian, then the dromaeosaurid foot 
is a symplesiomorphy of Aves. Of course this brings up problems like why 
did Archaeopteryx and other basal birds lose it? ( I think I heard about 
another sickle-clawed bird from Argentina ). 


<<I'm getting tired of these perfunctory analyses. What needs to be done 
is a careful assessment of all the characters that have been thrown 
around various recent papers on theropod and dinosaur systematics.>>

I agree that some analyses need to be more carefully studied in 
monographic format. Monographic papers have done wonders for avian 
systematics ( take Houde 1988, his classic analysis of paleongnathus 
birds and his concise and intuitive phylogeny for the group ). Olson and 
Feduccia in 1980 made two mongraphic analyses of flamingoes and duck and 
came up with the well-supported recurvorostid ancestry for the groups. 
We do need more analyses like them.

MattTroutman

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