My post on birds and dinosaurs yesterday led to a little debate on Facebook, including this, from paleontologist Thomas Holtz:
All living birds share a common ancestor that would also be considered a bird, so they are a monophyletic group. Nevertheless, that group is deeply nested among euornithine ornithothoracine pygostylian avialian eumaniraptoran paravian metornithine maniraptoran maniraptoriform tyrannoraptoran coelurosaurian avetheropodan tetanurine averostran neotheropod theropod saurischian dinosaurs.
…and breathe.
Originally published February 26, 2010. Copyright 2010 Carl Zimmer.