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Re: New Papers of the Ya-Ya Sisterhood

Smith's (2007) phylogenetic analysis removed _Acrocanthosaurus_ and _Neovenator_ from the Carcharodontosauridae and put them both in the Allosauridae (sensu lato).

The following SVP meeting abstract, also from this year, puts them back:

Stephen Brusatte & Paul Sereno: Phylogeny of Allosauroidea (Dinosauria: Theropoda): new analysis, comparisons, and sources of disagreement, p. 54A

Allosauroidea, a large-bodied clade of theropod dinosaurs ranging from the Middle Jurassic to the Late Cretaceous, has been the subject of several phylogenetic studies that have reached little consensus. We present a comparative cladistic analysis that attempts to integrate data from previous studies with new characters revealed by the description of several new allosauroid taxa from Africa and South America and the redescription of *Neovenator salerii* from the Early Cretaceous of England. First we review twelve previous studies of allosauroid phylogeny and discuss areas of topological disagreement. Second we compare our dataset to those of previous studies and evaluate the degree of overlap using novel comparative metrics that quantify shared character data. Our comparisons show that scoring differences, character choice, and taxonomic sampling are all major sources of incongruence. Importantly, numerous scoring differences highlight currently conflicting observations that must be resolved. Then we evaluate the status of the current understanding of allosauroid phylogeny and discuss the importance of rigorous comparative techniques in studies of dinosaur phylogeny. Finally we present our new analysis, based on 102 characters scored in 10 ingroup taxa, which represents the most extensive analysis of allosauroid phylogeny yet undertaken. The analysis strongly supports positioning *Sinraptor* as the basal-most [sic] allosauroid, *Neovenator* as the basal-most member of Carcharodontosauridae, and *Acrocanthosaurus* as a derived member of Carcharodontosauridae rather than a close relative of *Allosaurus*. This topology shows a strong overall match with the stratigraphic record, and cladistic biogeographic analysis suggests that the distribution of allosauroids is congruent with the breakup sequence of Pangaea.