[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
RE: Serration variation
> From: firstname.lastname@example.org [mailto:email@example.com]On Behalf Of
> Sent: Wednesday, February 09, 2000 7:48 PM
> In a message dated 2/9/00 7:35:38 PM EST, firstname.lastname@example.org writes:
> Neither behavior nor tooth shape has been shown to be independent of
> phylogeny. So who knows what "more" means in this context. Also,
> I don't know
> of any theropod group in which >lost< tooth serrations were
> >regained<. But
> there were surely theropods that evolved serrated teeth
> independently of one
> another, from smaller (birdlike) theropods that had tiny, unserrated
> teeth--the same kind as seen in Archaeopteryx.
One thing to be concerned with is developmental constraints: some authors
have suggested that the constructional mechanisms required to place the
serrations on teeth may only operate after the tooth is a certain size.
Absence of serrations on very small teeth *might* thus be of developmental
rather than phylogenetic significance.
Thomas R. Holtz, Jr.
Department of Geology Director, Earth, Life & Time Program
University of Maryland College Park Scholars
College Park, MD 20742
Phone: 301-405-4084 Email: email@example.com
Fax (Geol): 301-314-9661 Fax (CPS-ELT): 301-314-7843