Redbacks Spiders

New research has showmn that redback spiders eat male mates who do not spend enough time on foreplay. To keep cranky females happy, their partners have to spend about 100 minutes on courtship, doing things such as vibrating their webs and rubbing their tummies. But once the fickle babes are brought to a peak of amorous and receptive behaviour, they will let a stray male mate with them even if he hasn't done any courting at all. If he's quick, he can do the business and then run off before she gets a chance to eat him.

Research at the University of Toronto, in Canada, found Australian redbacks chose males based on a courtship duration threshold. If the first male did not spend enough time wooing the female, she would eat him before he had a chance to mate. But they found that once the female's courtship demands were met, other males could take advantage of the efforts of the first male. The scientists think their work may have clarified why clusters of males are seen around some females when other females remain uncontested.