Re: Sauropod Ancestors

[jshields@iol.ie (James Shields)]

>With regard to dinosaurs, I do not see how many major groups
>containing large species can be left to be discovered.

I'm getting WAY out of my depth here, but here goes...

As I understand it, the conditions for fossilisation are pretty rare.
Furthermore, there are environments in which it simply does not take place.
Isn't it possible that there are dinosaurs and groups of dinosaurs which
lived their lives in such places and simply did not wander into places where
they were likely to be preserved.

Couple this with the number of species we know must exist but don't have any
examples of. For example, we know saurischians and orinithischians must have
a common ancestor, but (unless I am mistaken) we have no idea of what that was.

I suspect that many of the specimens which share a name are actually
seperate related species. The only way we can be (reasonably) sure that two
fossils are from the same species is if they were found together. I'm not
suggesting that every new fossil find should be given a new name, rather
questioning whether we can give many fossils species names (or in some cases
even genus names) at all.

What I'm saying is that some species which are known from only a few teeth
or assorted bones cannot accurately be named other than calling them "A
tyrannosaur".

By the way, how is the number of known species estimated?


James Shields  -  jshields@iol.ie  -  http://www.iol.ie/~jshields
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And when the ark was finished Noah said unto Elvis, "What do you reckin?"
And Elvis checked out his own cabin and shook his head saying "poky".
And so did they knock several walls through and install a jaccuzzi.
And when it was all done Noah scratched his beard and said, "We don't have
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And Elvis perused the livestock list and in his wisdom said, "Lose the
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