Re: Were dinosaur ecosystems continent-sized? (resend)

[Jocelyn Falconnet <j.falconnet@gmail.com>]

GSP1954@aol.com a écrit :
> All the late Maastrichtian edmontosaurs are growth stages of E. annectens, 
> with copei being the mature stage with long shovel grazing beaks that do not 
> exist in specimens of 2 tonnes or less. Earlier E. regalis grew to the same 
> final size of 3 tonnes, but the beak never elongates or squares off. The 
> only major difference in the two taxa is the beak so Anatosaurus is a doubtful 
> genus.
>   
Do you mean 'genus', or 'species' ?
A genus IS doubtful if its type species is doubtful. If not, the genus 
MAY be considered as doubtful, and the type-species reallocated to 
another, close genus. The decision is up to the taxonomist, in this case.
Here is a summary of what you just said, considering each genus and type 
species:

*Anatosaurus annectens* = *Anatotitan copei*
*Edmontosaurus regalis* =/= *Anatosaurus annectens*

Hence: *Anatosaurus annectens* = *Anatotitan copei* =/= *Edmontosaurus 
regalis*

Keeping *Edmontosaurus annectens* and *Anatosaurus annectens* as two 
valid (here taxonomically speaking) genera does not shok me, nor sinking 
*Anatosaurus* into *Edmontosaurus* (oops, I'm not too sure about this 
part of the sentence... Damn Frenglish !!). And, as I suppose you're 
also a cladist, you just have to be define your genera in a way that 
they are monophyletic. You could also sink the whole dinosauria into the 
same genus that it would not shock me. Well, it would a complete mess 
afterwards for bird and other dinos friends, but as long as the taxon is 
monophyletic...
> It is interesting that a *hardosaur* clade was getting big into grazing when 
> that dang asteroid simply ruined things.
A *hardosaur* ? I don't even want to know why such a name was erected...

--
Jocelyn Falconnet