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Re: Fixing dinosaurian carnivour question



John M. Dollan said: "... by the way, I was unaware that the
classification of Aves under the
Dinosauria was universally accepted.  I may be wrong, but if it
isn't, than
why should we all be constrained in regarding birds as Dinosaurs on
this
list?  Of course, if it HAS been universally accepted, then, well,
never
mind...;)"

Most vertebrate paleontologists have reached a consensus on
osteological and morphological evidence that dinosaurs and birds are
closely related, and that birds are direct descendants of a group of
carnivorous dinosaurs (according to most, the maniraptorans =
deinonychus, velocirpator, etc.).  There are some paleontologists who
do not agree with the general consensus, and they argue a number of
different scenarios for the origins of birds.

With the advent of cladistics, the old Linnean classification system
is used less and less -- we mostly speak in terms of nodes and taxa,
although many journals still report Families, Classes, etc.  Since
natural groups (called monophyletic taxa) are the ancestor and all
descendants, if birds are descendants of dinosaurs (a monophyletic
taxon) then it is technically accurate to call them dinosaurs.  It is
also technically accurate to call ourselves sacropterygian fishes --
it depends on far you want to take it.

And I suppose I should add two things: 1) Nothing in science is
universally accepted, except perhaps scientific laws and 2) There are
no scientists vs. amateurs problems on this list as far as I can tell.
 People on this list are just trying to keep things clear and simple
by using the most concise language they can.  Asking what the smallest
carnivorous dinosaur is can technically be answered with a bird
taxon.

I have a question for Megaraptor:  Why do you want to know which
dinosaur was the smallest?

Matt Bonnan