Figure 2. Dominant male A. burtoni produce intentional sounds during courtship quivers.

A) Examples of the temporal sequence of courtship sounds and quiver behaviors produced by two individual males of different sizes. Top graph shows a small male (SL = 55 mm) that produced courtship sounds during ∼40% of behavioral quiver displays, while the bottom graph shows a larger male (SL = 82 mm) that produced sounds during ∼80% of quivers. Each vertical mark represents a single courtship sound or quiver behavior during the 30 min trial. B) Relationship between the percentage of quiver behaviors associated with courtship sounds and male standard length (SL) shows that larger males produce a greater proportion of behaviors with sounds than do smaller males.