Re: The iguanodont paper

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

Tim Williams writes: 

> I was only stating that it was evolution itself that derived birds from dinosaurs.

That's assuming that you define 'bird' as being a distinct group apart from, 
or sub-group within, 'dinosaurs'. A broader definition of 'dinosaur' would 
always include birds, in which case 'birds' aren't really 'derived' from 
'dinosaurs', since they still *are* dinosaurs. 

It would be like saying sauropods were derived from dinosaurs. 
Physiologically they were probably as far removed from other dinosaur groups 
as birds are - perhaps even more so. Put a sauropod, a non-avian theropod, 
an ornithopod and a bird all in a row and see which one looks like the 
odd-man-out. 

It all depends on where you draw the line between groups, which is an 
arbitrary thing at best. It seems that only us humans feel the need to 
categorise things into discrete (and completely arbitrary) units - which can 
be frustrating in a universe that is really one big fuzzy continuum. 

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Dann Pigdon
GIS / Archaeologist              geo cities.com/dannsdinosaurs
Melbourne, Australia             heretichides.soffiles.com
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