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Re: Wrong Reconstructions



Jaime,

On this paragraph:

>   The nests Varricchio is referring to are similar to those of *Citipati 
> osmolskae* in forming concentric rows of stacked eggs set in pairs around a 
> common center; this laying pattern is consistent with a single female laying, 
> rotating, laying, rotating, etc. and not consistent with multiple females 
> laying in a common clutch. At least some older papers referred nests now 
> considered to belong to *Orodromeus makelai* to "troodontids," showing a less 
> organized, erratic clutch pattern similar to that advocated by Varricchio of 
> "Troodon" in the Two Medicine.


I have two questions.

1) as far as rotating, do you dispute the conclusions of Varricchio et al. that 
the eggs being half - buried in sediment indicates that they were not rotated, 
and his speculation that the chalazae (which allow bird eggs to survive 
rotation, while those of crocodiles cannot) probably evolved further up the 
cladogram, closer to the Avialae?

2) Are you sure that the confusion about nest makers isn't the opposite of what 
you've written? I know that Horner assigned a clutch of 19 eggs, MOR 246, to 
Orodromeus, and that Varricchio reassigned it to Troodon when further 
preparation showed Troodontid synapomorphies in the embryos within the eggs. 
What specimen numbers are now "considered to belong to Orodromeus" that were 
formerly assigned to Troodon?

Thanks again.

-Jason