Figure 1.

Distributions of nonlinear measures ϕ_fj and ϕ_ch, respectively on the left and on the right, in four different two-parameter bifurcation diagrams: left-right U-fold asymmetry /lung pressure (diagram A), U-fold sizing /lung pressure (diagram B), size of the nasal cavities /size of the laryngeal sac (diagrams C,D). The represents parameter values normalized by their nominal values from Table 3. The simulated vocalizations of diagram C have been obtained with an upward fundamental frequency modulation, and those of diagram D have been obtained with a laryngeal sac extension.