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RE: At long last! Turner, Makovicky & Norell on dromaeosaurids
Strangely for a paper that sets out to review all known dromaeosaurids, there
is no mention of *Luanchuanraptor henanensis* Lü et al. 2007. Was this taxon
shown to be non-dromaeosaurid elsewhere?
> Date: Wed, 22 Aug 2012 15:29:47 -0400
> From: firstname.lastname@example.org
> To: email@example.com
> Subject: At long last! Turner, Makovicky & Norell on dromaeosaurids
> A major monograph, based in large part on Turner's dissertation work.
> Includes the first detailed osteologies for Adasaurus, updated
> Achillobator images, some taxonomic revisions, and more:
> Turner, A.H., P.J. Makovicky, and M.A. Norell. 2012. A review of
> dromaeosaurid systematics and paravian phylogeny. Bulletin of the
> American Museum of Natural History 371:1-206.
> doi: http://dx.doi.org/10.1206/748.1
> Coelurosauria is the most diverse clade of theropod dinosaurs. Much of this
> diversity is present in Paraves-the clade of dinosaurs
> containing dromaeosaurids, troodontids, and avialans. Paraves has over 160
> million years of evolutionary history that continues to
> the present day. The clade represents the most diverse living tetrapod group
> (there are over 9000 extant species of Aves-a word used
> here as synonomous with "bird"), and it is at the root of the paravian
> radiation, when dromaeosaurids, troodontids, and avialans
> were diverging from one another, that we find the morphology and soft tissue
> changes associated with the origin of modern avian
> flight. Within the first 15 million years of known paravian evolutionary
> history members of this clade exhibited a difference of
> nearly four orders of magnitude in body size, a value that is similar to the
> extreme body size disparity present today in mammalian
> carnivorans, avians, and varanoid squamates. In this respect, Paraves is an
> important case study in characterizing the patterns,
> processes, and dynamics of evolutionary size change. This last point is of
> particular interest because of the historical
> significance placed on the role of body size reduction in the origin of
> powered avian flight.
> Our study reviews and revises the membership of Dromaeosauridae and provides
> an apomorphy-based diagnosis for all valid taxa. Of the
> currently 31 named dromaeosaurid species, we found 26 to be valid. We provide
> the most detailed and comprehensive phylogenetic
> analysis of paravians to date in order to explore the phylogenetic history of
> dromaeosaurid taxa. The general pattern of paravian
> relationships is explored within the broader context of Coelurosauria with an
> emphasis on sampling basal avialans, because of their
> importance for character optimizations at the base of Paraves.
> A large dataset was constructed by merging two datasets, one examining
> coelurosaur relationships broadly (based on previous TWiG
> datasets) and the other examining avialan relationships specifically (Clarke
> et al., 2006). This merged dataset was then
> significantly revised and supplemented with novel character analysis focusing
> on paravian taxa. During character analysis,
> particular attention was given to basal members of Dromaeosauridae, enigmatic
> basal paravians such as Jinfengopteryx elegans and
> Anchiornis huxleyi, and the incorporation of new morphological information
> from two undescribed troodontid species from the Late
> Cretaceous of Mongolia. A final dataset of 474 characters scored for 111 taxa
> was used to address paravian evolution. This dataset
> is important in that it bridges a phylogenetic gap that had persisted between
> studies on birds and studies on all other
> coelurosaurs. Most scorings in this matrix were based on the direct
> observation of specimens.
> All most parsimonious trees recovered in the cladistic analysis support the
> monophyly of Paraves, Troodontidae, Dromaeosauridae, and
> Deinonychosauria. A new clade of basal troodontids is discovered including
> two undescribed Mongolian troodontids and Jinfengopteryx
> elegans. Xiaotingia and Anchiornis form a clade at the base of Troodontidae.
> Recently proposed relationships within Dromaeosauridae
> are further supported and a succession of clades from Gondwana and Asia form
> sister taxa to a clade of Laurasian dromaeosaurids.
> Avialan monophyly is strongly supported with Archaeopteryx, Sapeornis,
> Jeholornis, and Jixiangornis forming the successive sister
> taxa to the Confuciusornis node. This topology supports a more basal position
> for Sapeornis than previous phylogenetic analyses and
> indicates a progressive acquisition of a fully "avian" shoulder morphology.
> Taxonomic issues:
> In this monograph, they sink Linheraptor into Tsagaan mangas; Microraptor gui
> into M. zhaoianus; Sinornithosaurus haoiana into S.
> millenii; Variraptor considered a nomen dubium; Saurornitholestes robustus as
> a nomen dubium.
> A new clade Jinfengopteryginae is coined for all taxa closer to
> Jinfengopteryx than to Troodon formosus, Passer domesticus, and
> Sinovenator changii.
> 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
> Fax: 301-314-9661
> Faculty Director, Science & Global Change Program, College Park Scholars
> Fax: 301-314-9843
> Mailing Address: Thomas R. Holtz, Jr.
> Department of Geology
> Building 237, Room 1117
> University of Maryland
> College Park, MD 20742 USA