Female control of paternity in the sexually cannibalistic spider Argiope keyserlingi

Sexual conflict theory predicts an antagonistic coevolution, with each sex evolving adaptations and counter-adaptations to overcome a temporary domina nce of the other sex over the control of paternity. Polyandry allows sexual selection to operate after mating has commenced, with male and female inte rests competing for control of fertilization. There are numerous examples o f male control of paternity, but few studies have unambiguously revealed fe male control. Attributing variance in paternity to females is often difficu lt since male and female influences cannot be separated unambiguously. Howe ver, we show that polyandrous female orb-web spiders Argiope keyserlingi (A raneidae) control the paternity of their offspring by adjusting the timing of sexual cannibalism. Our experiments reveal that females copulating with relatively smaller males delay sexual cannibalism, thereby prolonging the d uration of copulation, and that these males consequently fertilize relative ly more eggs.