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Re-evolving Therizinosaurids



You wrote: 
>\
>>So in order for Therizinosauroidea to be a theropod, it would have to have
>it's >metatarsal I, which in your view was just cartalagous in it's
>predessors (which >would have to include the whole toe for it to work), then
>MT 1 re-'boneized'. 

>        The reossification of elements is pretty much a given (IMHO) in the
>geological record. The presence of bony sterna in some dinosaurs which seem
>to be descended from ancestors which lacked them can be explained by the
>element being present in cartilagenous form in predecessor species.

Another explanation, it just wasn't found. Either one is proably corret.

>
>
>>Just another way for cladist to explain something to fit what they want,
>and >not to see who impossible it really is.
>

        More like, just another way for someone who apparently isn't
>thinking about evolutionary pathways to take a cheap shot at someone who is.
>
Bull, I'm thinking about real bones, not numbers that are given to bones. Cold 
numbers that are used in Cladist anylasis. How some bones will have the 'same 
number' but look different. Nature dosen't go by the numbers! It
 throws curve balls that Cladagrams can't account for.


>>Reevolving a toe, that was totally >lost, to be exactly the way it's suppose 
>>to
>>be is totally insane. 
>        If you read the _Alxasaurus_ paper, you will note that the first
>metatarsal of therizinosaurs is *not* "exactly" like that of other four-toed
>dinosaurs, and actually (by some miracle of evolution) records its 
>re-evolution.
>  
Gee, that foot is incomplete, so am I missing something? Segnosaurus has all 
the metatarsals (4), so does Erlicosaurus, and a therizinosaurus. Did you read 
it?


      You really should stop getting all of your data from George ;).

I'd take his adivce over any (please I'm quoting from Alan Charig, so don't 
flame me) frothing cladist, any time.




Tracy