Several of the diagrams here are from my review of bird diversity and evolution (Naish 2012). For Tet Zoo articles on various of the subjects illustrated here, see...

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Naish, D. 2012. Birds. In Brett-Surman, M. K., Holtz, T. R. & Farlow, J. O. (eds) The Complete Dinosaur (Second Edition). Indiana University Press (Bloomington & Indianapolis), pp. 379-423.