A Basal Dromaeosaurid and Size Evolution Preceding Avian Flight

  title={A Basal Dromaeosaurid and Size Evolution Preceding Avian Flight},
  author={Alan H. Turner and Diego Pol and Julia A. Clarke and Gregory M. Erickson and Mark A. Norell},
  pages={1378 - 1381}
Fossil evidence for changes in dinosaurs near the lineage leading to birds and the origin of flight has been sparse. A dinosaur from Mongolia represents the basal divergence within Dromaeosauridae. The taxon's small body size and phylogenetic position imply that extreme miniaturization was ancestral for Paraves (the clade including Avialae, Troodontidae, and Dromaeosauridae), phylogenetically earlier than where flight evolution is strongly inferred. In contrast to the sustained small body sizes… 

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