Figure 3 in Comparative ossification and development of the skull in palaeognathous birds (Aves: Palaeognathae)

Figure 3. Evolution of embryonic and adult palatal morphology of the ratites (phylogeny sensu Bledsoe, 1988, palaeognathous characters 1–3 sensu Zusi & Livezey, 2006). Top row: adult morphology (Parker, 1869, 1891; Beddard, 1898; Simonetta, 1960; Zusi & Livezey, 2006; Silveira & Höfling, 2007). Bottom row: embryonic morphology. Gallus (Jollie, 1957), Rhea, Apteryx (Parker, 1891), and Dromaius are all stage 37; Struthio (Parker, 1866) is slightly older; Aepyornis (Balanoff & Rowe, 2007) and Eudromia (Tinamidae) are late-stage individuals. The palatine is shaded to facilitate comparison.