Re: Genetic Study Shows Snake Evolution

[Tony Canning <tonyc@foe.co.uk>]

Pluto77189@aol.com wrote:

> I see a bit of a logical flaw in this study.  Because snakes are not related 
> to monitors, and monitors are possibly related to mosasaurs, and mosasaurs 
> are the only aquatic lizard we know of form that time, snakes did not evolve 
> in water.
>

That seems a bit unfair to me - this study, as far as it goes, on the face of 
it refutes Lee's hypothesis of a monophyletic mosasaur/snake clade 
(Pythonomorpha).    I've always been sceptical of the aquatic theory; one 
reason is that I cannot reconcile it with the
deterioration of the snake visual system.

Ideally, the anguid/varanid/snake relationships need higher resolution, with 
more data and more species - 1 example from each 'lizard family' seems 
inadequate.

>
> It's kinda like that holy grail flawed logic--she's a witch because she 
> weighs as much as a duck...you know.
>
> Not that I disagree with the findings.  I think it's probable that all marine 
> snakes evolved from terrestrial SNAKES.  Eggs, body shape, etc.  The most 
> primitive snakes, or those with the most primitive features(remnants of rear 
> legs in pythons) are terrestrial.
>
> Look at all the legless lizards, and the lizards that are nearly legless--all 
> terrestrial.  Just like some dinosaurs were probably secondarily flightless, 
> some reptiles--maybe even some snakes--are secondarilary legless.

If you mean they lost their limbs, re-evolved them and lost them again, well 
that's certainly a novel suggestion...

regards

Tony Canning