[no subject]

[aegyptiacus@aol.com]

Mickey Mortimer wrote :
>Tim Donovan wrote-

>>   Is N. bohlini (c Aptian) really congeneric with N. brevispinus >>from the 
>> terminal Maastrichtian Pingling formation? It is unusual >>for a dinosaur 
>> genus to span two stages, let alone several. Could >>it have persisted due 
>> to biogeographical isolation of southern >>China?

>They are probably not congeneric.  See 
>>http://www.cmnh.org/dinoarch/2000Oct/msg00112.html for a somewhat >out of 
>date summary.

>Mickey Mortimer

Which brings back my question about *Suchomimus*/*Baryonyx* debate. How can you 
be sure that animals separated by both a long time and quite some space can be 
of the same genera, let alone the same species? How long is the gender 
*Tyrannosaurus* supposed to have existed? There can't be such a long life span 
for a gender (there's no definite rule, I admit it). It must evolve into some 
other genera (given some specific traits, submitted to human analyses), like 
mammals or birds or modern reptiles throughout time. Just human appreciation, 
IMHO, and so inherently subjective (while still honest and professionnal).
Cheers,
Jean-Michel