Figure 1.

Experimental set-up and female fertility in response to the sharing of MHC or microsatellite alleles. (a) Exposure of oestrous mares (in boxes) to one of the ten stimulus stallions. (b) Pregnancy rate per stimulus stallion (means ± 95% CI) in response to MHC sharing between mares (n = 191) and stimulus stallions. (c) Logistic plot illustrating that pairwise relatedness r is a poor predictor of pregnancy. To improve visibility, points are jittered randomly along the y axis within the range that corresponds to pregnant or not pregnant (see table 1 for statistics). (Online version in colour.)