Re: Archaeopteryx and Flight

[Stan Friesen <swf@ElSegundoCA.ATTGIS.COM>]

 From: NCLARK@museum.gla.ac.uk
 > 
 > I didn't realise that cladistics could confirm anything.  I thought it was 
 > based on parsimony and represents only the best-fit representation of 
 > relationships. 

The point is that it reveals nearest relatives, and thus necessary
phyletic splits.  True, you cannot rely on just the single most
parsimonious tree, but it is still possible to constrain the possible
tree topologies considerably.

 > Did the water birds in the late Cretaceous compete for the 
 > same food as the pterosaurs or were they specialised to feed on something 
 > the pterosaurs didn't.
 > 
Except for some specialists, like the flamngo equivalent, probably
not, but the necessary ancestral groups are another matter.

Unfortunately, I have not done the full analysis, and the preliminary
version I did was years ago, based on the data in the first edition
of "The Fossil Record".  Some of the identifications in there seem
to have changed, at least so it seems from "Fossil Record 2".  I need
to verify that someof the more derived groups are still attributed
to the Cretaceous.  For instance is the Lancian form originally
identified as a cormorant still so considered?  If so, that places
considerable constraints on times of origin for various groups.

swf@elsegundoca.attgis.com              sarima@netcom.com

The peace of God be with you.