Table 3.

Anatomical and functional differences in the vocal tract of domestic fowl (Gallus gallus) and the greater sage-grouse (Centrocercus urophasianus)

Domestic fowlSage-grouse (male)Sage-grouse (female)
Tracheal tympanum (fused rings near base of trachea)PresentAbsentAbsent
Caudal tracheal cartilagesLaterally compressed region of 4–5 cartilagesSix pliable rings, similar in size and shape to rest of basal tracheaCartilages similar in size, shape and ossification to rest of basal trachea
Site of sound productionBase of trachea (unpaired)Bronchial–syringeal junction (paired)Bronchial–syringeal junction (paired)
Intrinsic syringeal musculatureAbsentVery robustAbsent or virtually absent
  • See Figs 1 and 7 for photographs