Figure 4
Correlation of male and female timing parameters across populations.
(A) Map of southern France and northeastern Spain showing locations of the 17 E. diurnus populations sampled between 2012–2015 (see ref. 30); map was generated with ArcGIS version 10.0 for desktop, ESRI (http://www.esri.com/software/arcgis/arcgis-for-desktop). (B) Ordinary least-squares linear regression of m (minimum post-stimulus call delay in males; Fig. 3B) vs. f (maximum leader-follower call separation for which females prefer the leading call; Fig. 3C) for the 17 sampled populations (m = 31 + 0.79 f; t = 6.56, p < 0.001). (C) Ordinary least-squares linear regression of m vs. f as in Fig. 4b but restricted to those 10 populations where the mean call syllable number in males was ≤2.1 (m = 207 + 0.37 f). Stepwise linear regression (α to enter and α to remove = 0.15) of m on both f and mean syllable number yielded the above model that only included f.
