Re: PYTHONOMORPHA REVISITED

[Adam Yates <zooamy@zoo.latrobe.edu.au>]

On Thu, 6 Feb 1997, Darren Naish wrote:

> 
> Also worthy of note here, though not relevant to this particular paper, is the
> mosasauroid taxon Natantia which I have seen used in a couple of cladograms. I
> think the name has already been used for a bunch of ostracod crustaceans, in
> which case it can't be used for the mosasauroids. I don't doubt that Lee's
> hypothesis will be much debated (much like all that turtle phylogeny work.. 
> err,
> this _is_ the same Lee isn't it?): Rieppel for one has voiced serious 
> objections
> to the idea of snakes as varanoids (some of the funny little burrowing snakes
> share odd characters with amphisbaenians and scincoids).


The interesting thing about Lee's phylogeny is that it turns all those 
funny little burrowing snakes into a monophyletic group, rather than a 
paraphyletic grade of basal snakes as in past hypotheses. This of course 
suggests two things 1) a fossorial phase in early snake evolution is less 
likely & 2) The characters shared between the fossorial snakes and 
amphisbaenids are not necessarily primitive for snakes. Indeed I suspect 
a fossorial existance places quite an evolutionary "straight jacket" on 
lepidosaur groups creating quite an impressive set of convergences.

"Ah, heres the results of the sci-scan now. It says we're going to 
..........live"

Adam Yates