Figure 3.

Interactive effects of population density and emission rates on theoretical information throughput (S) of a shared acoustic communication channel following the function S = λe^2λ, where λ = rτⁿ. (A) calculates information throughput assuming a conservative overlap window (τ) of 10 ms while (B) assumes an empirically-determined overlap window of 80 ms. In both graphs throughput is maximized at progressively slower emission rates as group size increases. In B the peak S is achieved at an optimum emission rate 3.25 Hz/bat for pairs of bats, 2.0 Hz/bat for triads, 1.25 Hz/bat for groups of five, and 1 Hz/bat for groups of ten.