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Re: Jurassic Fight Club on T-Rex & T rex infections

> Jurassic Fight club stating that T. Rex appears around 90 mya 
> and "ruled it" for 25 million years - all my up-to-date books 
> state this guy showed up only a few million years before K-T? ??
> Was this a major boo-boo?
>A boo-boo, yes. A major one? Well, there are plenty of worse errors in JFC,
>sad to say...

>But yes, T. rex persisted for only a few (or possibly less than 2) million
>years before the Big One.

So this really depends on what you call T. rex. The Hell Creek - Frenchman - 
Scollard tyrannosaurids ("classic" T. rex) fall within 1-1.5Ma of the K-T 
boundary. For the most part, the Lance Fm is the same age, but may be slightly 
older at its base in some sections. this isn;t a big deal since not much 
material (if any) is collected from this low in the Lance.

The material from Texas and Utah that has been attributed to T.rex is slightly 
older. The Javelina (TX) material has an ash date of 69Ma for the middle of the 
formation, so if you really wanted you could extend T. rex down to here if you 
want (and possibly, beyond by about another 500,000 - 1M years maybe. The Utah 
material is at the very least about 67Ma, and possibly a few my. older. This 
may account for the slight morphologic variation from the classic K-T rex 

I tend to be conservative and call the non-Hell Creek-Lance-Scollard-Frenchman 
material as Tyrannosaurus sp.

Denver Fowler