[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
RE: tiny-armed theropods
On Sat, October 15, 2011 11:51 pm, Anthony Docimo wrote:
It would seem to me that, if the _Troodon_ tooth morphology matches two
> or more troodontid genera (I assume you meant genera), then you'd know
> which troodontid clade _Troodon_ belongs to (which, granted, it was
> probably already grouped in).
If and only if that the two or more taxa who share this morphology share
it as a synapomorphy, not as a convergence.
> Is it possible for multiple genera to have identical teeth?
> Even if
> they're 99% similar, surely that remaining 01% could be used to determine
> the closest relatives of the _Troodon_ type fossil tooth.
Here is the problem: two individuals of the same ontogenetic status in the
same population might not have teeth that are 99% identical in the same
tooth position. The same individual might have teeth in the same tooth
position but opposite sides that are not 100% mirror images. The same
individual might have teeth in that position that are not 99% identical
from one tooth eruption to the next.
Sorry if this messes up people's typological worldviews, but *variation*
is the great reality.
So the issue is whether the _Troodon formosus_ tooth type can confidently
fit into the variation of one, but only one, species of skeletal taxon.
Thomas R. Holtz, Jr.
Email: firstname.lastname@example.org Phone: 301-405-4084
Office: Centreville 1216
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
Faculty Director, Science & Global Change Program, College Park Scholars
Mailing Address: Thomas R. Holtz, Jr.
Department of Geology
Building 237, Room 1117
University of Maryland
College Park, MD 20742 USA