Extended Data Fig. 1: Male mice avoid mounting sick females.

a, b, Male mice were presented with a pair of oestrus female mice 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 behaviours while engaged in direct interactions with a PBS or LPS female (e, f). Percentage of individual female behaviours during males’ mounting attempts (g) and the number of cage crossings (h). Representative traces of male and female behaviours 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). Data are mean ± s.e.m. Pvalues are described in the Supplementary Statistical Information.