Fig. 8.

Total offspring number versus number of uterine scars for the experimental females (F₁’s and backcrosses). Females are separated into three categories: F₁ between the races CHBU and CHHN (N = 19), females from backcrosses with 2n = 23 (BC.23, N = 4), and females from backcrosses with 2n = 24 (BC.24, N = 8). The dashed line indicates where the number of scars equals the number of total offspring i.e. every embryo that was implanted survived until birth. Females above the dashed line had more scars than offspring, indicating the loss of implanted embryos. The comparison of cross duration for the different females shows that it was not a major explanatory factor for differences in scar and offspring number