Palaeognathae
Palaeognathae includes five living branches of flightless birds (plus two extinct clades), called ratites, and one flying lineage, the Neotropic tinamous. There are 47 species of tinamous, five of kiwis (Apteryx), three of cassowaries (Casuarius), one of emus (Dromaius) (another emu became extinct in historic times), two of rheas (Rhea) and two of ostriches (Struthio).