Re: tweet-tweet

[Dann Pigdon <dannj@alphalink.com.au>]

evelyn sobielski writes: 

> If they are used to denote major shifts in ecological
> niche/ecomorphology, they are not arbitrary and
> actually quite useful - as they will then also denote
> a major shift in *how* evolution acts upon a lineage.

I get the impression that crocs are called reptiles mostly because of their 
sprawling gait and ectothermy - both of which appear to be secondarily 
re-aquired. Lumping crocs in with other reptiles inevitably drags the rest 
of the archosaurs in with them - even if they don't live up the 
sprawled-gaited, ectothermic stereotype. 

Perhaps archosaurs deserve a class of their own? How about redefining Aves 
to include the most recent common ancestors of birds and crocs? That'll set 
a croc among the pigeons... :) 

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Dann Pigdon
GIS / Archaeologist              http://geo_cities.com/dannsdinosaurs
Melbourne, Australia             http://heretichides.soffiles.com
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