Fig. 2. Relationship between downwind approach distance d and wind speed. (A) The distribution of wind speeds in the desert near Maharès (bin width 0.5 m s^-1; recordings (n=1961) taken between ca. 08:00 h and 16:00 h, between 19 August and 5 September 2002, and 22 June and 3 July 2004). (B,C) The relationship between wind speed (bin width 0.1 m s^-1) and downwind approach distance d. In B, data from all experiments are pooled; in C only data recorded for the 5 mnest-feeder distance are shown. (D) The pooled data from all experiments, as in B, but the individual values were corrected for the dependency of d on nest-feeder distance D, effectively eliminating any bias introduced by this dependency into the relationship between wind speed and d. Values are means ± S.D. (D), +1 S.D. (B,C).