<==o PALEOGNATHIA (vanhaleukaiset nykylinnut)
   |?- †Eremopezus eocaenus Andrews, 1904 [Paleognathia incertae sedis]
   |?- †Stromeria fajumensis Lambrecht, 1929 [Paleognathia incertae sedis]
   |?- †Remiornis minor [REMIORNITHIFORMES: Remiornithidae]
   |?-o †Eleutherornithidae [Paleognathia incertae sedis]
   |  |-- †Eleutherornis helveticus
   |  `-- †Proceriavis martini
   |?- †LITHORNITHIFORMES
   |?- †AEPYORNITHIFORMES (norsulinnut)
   |-- TINAMIFORMES (tinamilinnut)
   `--+-- †DINORNITHIFORMES (moalinnut)
      `--+-- RHEIFORMES (nandulinnut)
         `--+-- STRUTHIONIFORMES (strutsilinnut)
            `--+-- APTERYGIFORMES (kiivilinnut)
               `-- CASUARIFORMES (kasuaarilinnut)

Reference(s):

Feduccia, A., 1980: The Age of Birds.
–Harvard University Press, Cambridge, Massachusetts & London, England, 1980, ix-196

Feduccia, A., 1996: The origin and evolution of birds.
–Yale University Press, New Haven and London, 1996, xii-420

Haddrath, O. & Baker, A. J., 2001: Complete mitochondrial DNA genome sequences of extinct birds: ratite phylogenetics and the vicariance biogeography hypothesis.
--Proceedings of the Royal Society of London: Biological series: Vol. 268, pp. 939-945

Olson, S. L., 1985: The fossil record of birds. 79-239.
in Farner, D., King, J. & Parkes, K. (eds.), 1985: Avian Biology. vol VIII.
–Academic Press, New York. 1985.

Rasmussen, D. T., Olson, S. L. & Simons, E. L., 1987: Fossil birds from the Oligocene Jebel Quatrani Formation, Fayum Province, Egypt.
--Smithsonian Contributions to Paleobiology: No. 62, pp. iv-20

Sibley, C. G. & Monroe, B, L., 1990: Distribution and taxonomy of birds of the world.
–Yale University Press, New Haven & London, 1990. xxiv-1111.