Predicting Achievable Fundamental Frequency Ranges in Vocalization Across Species
Fig 5
Contour plot of predicted fundamental frequency range (high/low, fo2/fo1 ratio) for morphological variables B and L2/L1.
The range depends on two important factors: the rotational flexibility of the laryngeal framework, which facilitates L2/L1; and the B value that quantifies the tissue stress response to elongation. For a given B value, a larger fundamental frequency range can be achieved with greater rotational flexibility. For a given L2/L1 ratio, a larger frequency range can be achieved with a greater B value. Note that the changes in the B value are not large to achieve a larger frequency range for a given a given L2/L1 ratio.