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RE: ...and how ranks don't work was Re: Sauropodz r kewl







> Date: Thu, 19 Apr 2012 13:33:44 +0200
> From: david.marjanovic@gmx.at
> To: dinosaur@usc.edu
> Subject: ...and how ranks don't work was Re: Sauropodz r kewl
> 
> Am 18.04.2012 17:01, schrieb Anthony Docimo:
> 
> > We've demolished groups such as Pachyderma, relocating its members
> > (rhinos, elephants, etc) to their true relatives...and yet the
> > tuatara, aardvark and pangolin are set aside in their own groups with
> > no near extant relatives. so, if there is no way to quantify it, why
> > do we keep them separate?
> 
> Because we think in trees.

 

 Danged primate ancestry.  :)

 

> Rhynchocephalia and Squamata are sister-groups. To put *Sphenodon* (and 
> the extinct rhynchocephalians) into Squamata would just mean we'd 
> confuse everyone and need to come up with a new name for what we used to 
> call Squamata. Note how I wrote this without mentioning a rank once.

 

Oh I understand how that's possible for a discussion between people who both 
know what the names imply.

 

It's like if we held conversations in German or in Damin - we would each know 
what the other is saying and meaning...but if we want to tell anyone else about 
what we're talking about and working on, we would have to use a language they 
know: ranks.

 

 

> > > So the differences that make up the phyla represent 'huge'
> > > differences that accumulated over a long period of time, and
> > > therefore the phyla originated in the pre-Cambrian. Orders in the
> > > Cretaceous, etc. Again, not advocating that, but I think that's the
> > > idea behind it.
> >
> > ah, okay; yeah, that makes sense for things further away in deep
> > time.
> 
> Only because the fossil record isn't any better. If it were, we'd run 
> into the problem I just explained using birds.

 

 Who suggested birds should get their own phyla?  I'm just agreeing that most 
phyla are roughly Cambrian in age.