Figure 1

Characteristics of lab-based An. gambiae swarms. (a) and (b) the number, NR, of mosquitoes released into the cage, for each generation of males (left) and females (right). NR is in the same range, between approx. 800 and 2000, in both cases, but is less variable for females. (c) and (d) The number, N, of mosquitoes participating in 28 acquisitions of single-sex male swarms (left column) and 34 single-sex female swarms (right column) are shown. Different colours refer to different generations. Male swarms are on average larger (mean ± standard deviation, 138 ± 84.6) than female swarms (48 ± 34.4). (e) and (f) N is averaged over all acquisitions of the same generation, left column for male swarms and right column for females. Data represents mean ± standard deviation. (g) and (h) Nmax, the maximum number of swarming mosquitoes across all acquisitions of the same generation, as a function of NR. In males Nmax depends linearly on NR (Pearson coefficient 0.88 – p value 0.005). The slope of the linear fit, equal to 0.19, represents the typical participation ratio in male swarms. In females the linearity between Nmax and NR is not evident.