[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: "Megapnosaurus" says farewell...



>But, it is still as subjective as grouping rabbits and _Syntarsus_ into the
same genus.<
How is this any different than fossil species? What is the cladistic
definition of a species? Temporal? Morphological? Why not run cladograms
based on individual specimens, as opposed to species, that (at least to me,
the uncladistically-oriented) appear just as arbitrary as a genus, family,
order, etc.
Peace,
Rob

Student of Geology
P.O. Box 20840
Flagstaff, Az. 86011
http://dinodomain.com
http://www.cafepress.com/robsdinos
AIM: TarryAGoat
"A _Coelophysis_ with feathers?"

Convenience, like subjectivity, shouldn't be what guides scientists.
Otherwise, Avogadro's number could be designated as 6.0 x 10^23.
Convenient?  Yes.  Correct?  Only partially.
>
> ><< I have never quite understood why _Psittacosaurus_ has something like
> >seven or eight valid species, but _Coelophysis_, _Syntarsus_ (Raath),
> >_Eucoelophysis_, etc. were placed in separate genera.  It's aesthetic
> >philosophy, not science sensu stricto. >>
> >
> >So far nobody has been able to come up with a consistent way to group
> >together the various species of Psittacosaurus. You either have x species
or
> >x genera. They all look enough alike that the species level is considered
> >more appropriate.
>
> Exactly.  Nobody has been able to subjectively come up with a consistent
way to group the species of _Psittacosaurus_ into anything but one genus.
In this case, as George said, the species level is _considered_ more
appropriate.  However, there is no widely-accepted definition or principle
that merits this.  I think we all know that.
>
> Regards,
> Steve
>
> ****
> Steve Brusatte
> Dino Land Paleontology
> http://www.geocities.com/stegob
> ****
>
>
> Go Get It!
> Send FREE Valentine eCards with Lycos Greetings
> http://greetings.lycos.com
>