Re: Tyrant stuff (no longer ranting) (was RE: Rant (was RE: Details on SVP 20...

[Dinogeorge@aol.com]

In a message dated 11/9/02 6:04:23 AM EST, qilongia@yahoo.com writes:

<< No argument there. I mean, a St. Bernard is also _so_ different from a
 Chihuahua, too. Then there's the columbid *Didunculus*, the dodo. Nested
 right inside all the rock doves, pigeons, and so forth. Extreme variation
 can occur in any well-associated taxa, given circumstances. >>

With fossil vertebrates all we have are bones, so when the bones are 
sufficiently different, this is prima facie evidence that the individuals 
belonged to different species, or genera, or families. We haven't a clue as 
to whether this notion is correct, since there's no way to test the 
interbreeding ability of extinct animals. Heck, Nopcsa once proposed that 
lambeosaurids were the males of suitable hadrosaurids--an idea that Peter 
Dodson eventually worked out in a plausible way. I see no way to determine 
whether two fossils belong to the same species except via time machine. 
Ultimately, it's all guesswork, cladistics or no.