Anti-predation behavior resolves sexual conflict over mating rate and duration in a protandric-simultaneous hermaphrodite.

The reproductive interests of males and females rarely coincide, and thus, sexual conflict should be widespread in sexual species and favor the evolution of traits that bias the outcome of mating interactions towards the participant's own interests. Sexual conflict theory has achieved considerable sophistication since its formal proposal. Yet, the evolutionary implications of this process in species other than those with separate sexes remain ill-explored. I examined sexual conflict in Lysmata wurdemanni, a shrimp that exhibits protandric simultaneous hermaphroditism, a peculiar sexual system where individuals invariably mature and reproduce as male first before becoming simultaneous hermaphrodites. In Lysmata wurdemanni, exacerbated mating costs for female-role individuals included death by too-eager-to-mate male-role individuals and resulted in the unprecedented employment by female-role hermaphrodites of anti-predatory tactics (escape response consisting of a backward tail flipping that rapidly propel shrimp away from danger) to actively resist harassment and to exert control over copula termination. Sexual conflict does occur in species featuring unconventional sexual systems and likely has implications for sex allocation patterns.