Extended Data Fig. 5: Axial CT and µCT images of the SPD across Aves (part 1).
From: The respiratory system influences flight mechanics in soaring birds
Each axial slice was selected using the MPR as in Extended Data Fig. 3. Purple text and arrows indicate presence of the SPD. a, Southern cassowary (Casuarius casuarius). b, Emu (Dromaius novaehollandiae). c, Common ostrich (Struthio camelus). d, Elegant crested tinamou (Eudromia elegans). e, Falcated duck (Anas falcata). f, Northern pintail (Anas acuta). g, Redhead (Aythya americana). h, Spectacled eider (Somateria fischeri). i, Steller’s eider (Polysticta stelleri). j, Canada goose (Branta canadensis). k, Trumpeter swan (Cygnus buccinator). l, Tundra swan (Cygnus columbianus). m, Helmeted curassow (Pauxi pauxi). n, Chicken (Gallus gallus). o, Crested partridge (Rollulus roulroul). p, Anna’s hummingbird (Calypte anna). q, Tawny frogmouth (Podargus strigoides). r, Violet turaco (Musophaga violacea). s, Nicobar pigeon (Caloenas nicobarica). t, Black crowned crane (Balearica pavonina). u, Western grebe (Aechmophorus occidentalis). v, Chilean flamingo (Phoenicopterus chilensis). w, Black-necked stilt (Himantopus mexicanus). x, Common murre (Uria aalge). y, Western gull (Larus occidentalis). z, Pacific loon (Gavia pacifica). aa, Common loon (Gavia immer). bb, Yellow-billed loon (Gavia adamsii). cc, Sooty shearwater (Puffinus griseus). dd, Brandt’s cormorant (Phalacrocorax penicillatus). ee, Scarlet ibis (Eudocimus ruber).