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RE: Resending


FlxLandry@aol.com wrote:

And, more generally, is it really more interesting to know where Torvosaurus fit on the cladistic tree than to know what it looked like and how it lived?

To add to what Mickey already said, these two issues (ecomorphology and phylogeny) are not mutually exclusive. To give an example, we can gain insights into the lifestyle of _Tyrannosaurus_ by examining the order in which characters were gained or lost in the lineage leading to _Tyrannosaurus_. So far, we have learned that changes to the jaws and teeth preceded the drastic reduction in forelimb size in tyrannosaurs. But tracking these changes, and observing *how* they happened, we can gain a better understanding as to *why* these changes occurred from basal tyrannosaurs to the great _Tyrannosaurus_.

Another example is the behavior of early birds. The discoveries of small feathered taxa like _Microraptor_ and _Sinornithosaurus_ has the potential to provide insights into the origin of avian (bird) flight. Phylogenetic analyses have revealed just how close these forms are to the base of the bird lineage, allowing us to build hypotheses about how aerial locomotion evolved, and how it was expressed by the earliest known birds. For both this example, and for the tyrannosaur example above, biomechanical analyses can gain additional rigor when placed in a phylogenetic framework.

(From a previous email:)

I tend to have
a subjective preference for saving old names  even if their meaning has to
change (isn't there a Brontosauria somewhere???),

Brontosauria was erected by Olshevksy (1991) to include all prosauropods and sauropods; Olshevsky made Brontosauria and Segnosauria the two "orders" within the "superorder" Sauropodomorpha. (This is back when Olshevsky did not regard segnosaurs/therizinosauroids as theropods, but as sauropodomorphs; he has since changed his mind.) Olshevsky erected Brontosauria in a non-cladistic context, and the term is currently without a definition.

but there is also a practical
reason for it: if we have to invent new names  every time cladistics show a
new clade, we'll soon run out of names...


I very much doubt that we'll ever run out of names.  :-)

Cheers

Tim