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RE: Turtles and Crocodylians are not Reptiles - no? What are they?

Leonardo Torres wrote:

> I prefer the term reptiles is used as a synonym of amniota, because that
> include not only the actual grups but a evolutionary history of the group,
> since the traditional systamatic don't have a evolutionary concept in his
> origin, creates problems with aplication of the names.
> I's importante consider the historical use of a term. 

I agree that we should consider the historical usage of a term - as a general 
principle.  Trouble is, "historical usage" can be self-contradictory in certain 
cases.  The first amniotes were also the first 'reptiles', and the ancestors of 
birds and mammals have Reptilia traditionally been referred to as 'reptiles'.  
However, Reptilia also excluded birds and mammals, both of which are amniotes.  
So the Reptilia never included Aves or Mammalia.  So in framing a phylogenetic 
definition of Reptilia it's impossible to satisfy all the criteria of 
"historical usage".

Certain terms that were used historically should be abandoned because they are 
misleading, or connote (or denote) obsolete concepts.  'Reptilia' might fall 
into this category - this is a matter of opinion.  Personally, I prefer the 
name Sauropsida for the group that includes all extant reptiles, as well as 
birds, but not mammals (which are synapsids, not sauropsids).  If Reptilia is 
the same as Sauropsida, then mammals did not evolve from from 'reptiles', which 
is a departure from the historical usage of the term 'reptile'.

But other names are certainly best forgotten, because they are polyphyletic in 
content - such as Cuvier's Pachydermata, and Vermes (which you mention)...

> The class  Vermes is
> no longer used, but  in  portuguese  the  word reffers to all intestinal
> parasites and others worms, besides in school the kids was teached to
> use the correct names of the grups Platyhelminthes, Nematoda and 
> others.



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