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Re: Heterodontosaurid with protofeathers



On Thu, Mar 19, 2009 at 12:54 PM, David Marjanovic
<david.marjanovic@gmx.at> wrote:
> In a sense it is: if the name doesn't refer to anything that's similar to
> the concept that's historically associated with it, it's good if it
> self-destructs, because that means it's associated either with more or less
> the same concept or with nothing at all.

Well, I would not call it stabilization - the same way that I would
not call extinction as adaptation.

>> Someday I will test the stability of some definitions - cladistic and
>> non-cladistic ones - in a retrospective manner. Let's say, if we apply
>> the _Passer domesticus_ + _Triceratops horridus_ definition of
>> Dinosauria back into 1889 how would be their tree topology (a tree
>> constructed with phylogenetic analysis and the characters state as
>> known at that time)?
>
> Phylogenetic analysis did not exist back then. Phylogenetics was not a
> science back then*, it was an art. -- Also, what would your exercise be good
> for?

It will suffice that there were descriptions of the species and
specimens. Based on it, we could run a phylogenetic analysis. Such
analysis could test the claim that node- or branch-based definitions
are more stable. If the topology remains the same as present day
topology (obviously it would be more simplified, since will have fewer
terminals), we could consider that such definition is stable over
time.

[]s,

Roberto Takata