Courtship and male discrimination between virgin and mated females in the orange tip butterfly Anthocharis cardamines

Recent evidence implies that male butterflies incur non-trivial costs in producing ejaculate, and that the number of ejaculates they can produce is limited. Therefore males should be expected to show some mate discrimination. In butterflies, the reproductive value of females, by necessity, decreases with age and, therefore, males should be expected to court young virgin females more intensively than old mated females. In the orange tip butterfly, Anthocharis cardamines, we show that males exhibit behaviour consonant with this hypothesis. They court unreceptive virgin females for approximately 60 s before giving up, whereas unreceptive mated females are courted for only about 3 s before the male departs. We also show that receptive virgin females usually detain courting males by performing an ‘elevated abdomen’ display for about 4 s before accepting the male, and that this display is identical in form to that used by mated females to reject courting males.