Male mating preference for female survivorship in the seaweed fly Gluma musgravei (Diptera : Coelopidae)

The seaweed fly mating system is characterized by pre-mating struggles duri ng which females exhibit a mate rejection response involving kicking, shaki ng and abdominal curling. Males must resist rejection until females become passive and allow copulation to take place. However, despite the vigorous n ature of the struggle males frequently dismount passive females without att empting copulation. Here we show that rejected females suffered higher post -encounter mortality rates than those accepted by males in the seaweed fly Gluma musgravei. Furthermore, we show that males also preferentially mounte d females with higher future longevity. We propose that this male mate choi ce for female survivorship has evolved as a result of females often having to survive for long periods after mating until suitable oviposition sites b ecome available. Such male preferences for female survivorship may be commo n in species in which oviposition must sometimes be substantially delayed a fter mating.