Extended Data Figure 1. Male mice avoid mounting sick females.

a,b, Male mice were presented with a pair of estrus females each injected intraperitoneally with either PBS (PBS-female) or LPS (LPS-female) (a). Mounting time during a 10-min test (b) (n=9; from 2 independent experiments). c, Mounting time for male mice presented with two untreated, healthy females (n=8; from 2 independent experiments). d, Investigation time of PBS- and LPS-females during a 10-min three-chamber assay (n=5; from 2 independent experiments). e-i, These data are associated with Fig.1a–e. Duration of other typical male behaviors while engaged in direct interactions with a PBS- or LPS- female (e,f). Percentage of individual female behaviors during males’ mounting attempts (g) and the number of cage crossings (h). Representative traces of male and female behaviors during direct interactions (i). **P<0.01, ***P<0.001 and ****P<0.0001 calculated by paired two-tailed t-test (b), two-way ANOVA with Sidak’s post-hoc test (f,g) and unpaired two-tailed t-test (h). Graphs indicate mean ± s.e.m. p-values are described in the supplementary statistical information file.