Fig. 4.

Histogram showing the mean percentages of putatively polyploid nuclei (with multiple hybridization signals) in mouse corpora lutea in three groups of superovulated females. The mean and standard error are shown for percentages calculated separately for each corpus luteum. Females in the ‘no male’ group were not housed with males. Females in the ‘no plug’ group were housed overnight with vasectomized males but did not have vaginal plugs the following morning so there was no evidence of mating. Females in the ‘mated’ group were housed overnight with vasectomized males and had vaginal plugs the next morning (evidence of mating).