Re: mammal-like reptiles is a good name?

["Nicholas J. Pharris" <pharrinj@PLU.edu>]

On Tue, 7 May 1996, Mark Sumner wrote:

> I'm sorry, I didn't mean to infect the mailing list with an
> argument over triviality, but...
> 
> Why should the term "mammal-like reptile" imply that "the early
> synapsids did not give rise to the mammals?"  [...] This term, for me, 
> clearly demonstrates the transitional nature of these synapsids, 

"Transitional" to me, at least, implies "intermediate between two 
groups."  This does not accurately describe the evolutionary position of 
animals like _Dimetrodon_.  Such animals are _basal_.  They are early 
members of a group (Synapsida/Theropsida) which branched off before the 
development of those characteristics which we usually associate with 
members of that group (erect posture, endothermy, hair, etc.) and hence, 
to us, resemble earlier, non-synapsid amniotes.  

They have no connection with reptiles, the *general* conformation of 
some of whom (i.e. lizards) also happens to resemble that of early amniotes.

We appear to be running around with (at least) two different definitions 
of "reptiles."  And so I say again:  Throw the term out!

> And, hey, what's wrong with "non-avian dinosaurs?" <g>

Now *there's* a sentiment I agree with!

> Mark

Nick Pharris