Figure 1.

Mice did not differ in the number of alcohol reinforcers earned, despite differences in rate of responding. a, All genotypes received equal access to alcohol reinforcers across acquisition. b, Access to alcohol relative to body weight was comparable across groups. The average grams per kilogram consumed per session was equivalent across groups (inset). c, XY mice and mice who developed testes made more active nosepokes per minute than did XX mice and mice that developed ovaries. *Interaction effect XY chromosome and male gonad, p < 0.05. Error bars represent SEM. Post hoc analyses conducted with Tukey's HSD. XYM n = 16, XYF n = 12, XXM n = 14, XXF n = 13.