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Re: So are turtles now crocodiles?



I won't pretend to know too much about genetics (outside of phenotypic
plasticity within populations of freshwater aquatic species--the only thing
I've really looked into), but I personally feel that there is a high
potential for homoplasy with all the genes that can be turned on or off by
inhibitor genes and what not.  Isn't there a caudate amphibian with a genome
something like seven times the size of the human genome?  Wouldn't this
increase the potential for shared traits?  

My point is, genetic phylogeny isn't something to be used by itself (at
least not at the present time), especially when looking at higher level
taxa.  Some of the work being done on specific families is truly valuable
(look at the discovery of the close _Puma_/_Acinonyx_ connection).  Genetics
is best implemented, however, when complemented by a look at the fossil
record, a recent example of this was the paper by our own Dr. Chris Brochu
who analyzed the phylogenetic position of _Gavialis_ (don't have the paper
in front of me now or I would give the full citation).  

To keep this response slightly on topic at least, I will pose the question
where birds (and therefore the non-avian dinos as well) fit into this little
study we're talking about?  I haven't seen the paper, but if turtles are
crocs' closest living relatives, where are our other archosaurian buddies?