Re: paleonet Czerkas and Norell in Discover

[Dinogeorge@xxxxxxx]

In a message dated 7/26/2005 3:59:15 PM Pacific Standard Time, tijawi@yahoo.com writes:

I'd be intrigued to know how Clark et al. were in "error", and that they were actually studying a prosauropod skull without knowing it.

For one thing, they misidentified the parasphenoid as the basisphenoid. In segnosaurs the basisphenoid is inflated with cavities, in bullatosaurs the parasphenoid is inflated with cavities, yet these are scored by them as equivalent in the two taxa. I recall posting on this on the DML a few years ago. "Inflated basiphenoid" is a segnosaur autapomorphy, not a segnosaur-bullatosaur symplesiomorphy.

 

They weren't studying a prosauropod skull, they were studying a segnosaur skull.