Sexual and nonsexual cannibalism have different effects on offspring performance in redback spiders

Sexual cannibalism is often set apart from other forms of cannibalism; however, no studies have directly compared the fitness consequences of these 2 types of cannibalism. Here, we compared the consequences of cannibalism of a male by a female outside the context of mating (referred to as nonsexual cannibalism) and within the context of mating (referred to as sexual cannibalism) for the propensity to remate, fecundity, and offspring traits of female redback spiders Latrodectus hasselti. Although the timing of cannibalism relative to copulation is critical for male fitness, it is still unclear whether it can also influence female fitness, beyond the fertilization of eggs. Our results showed that sexual cannibalism and nonsexual cannibalism had different effects on offspring survival and growth. Sexually cannibalistic females produced offspring that survived better and grew faster than nonsexually cannibalistic or noncannibalistic females. By experimentally manipulating the quality of pre...