Data from: Coexistence of sexual and asexual reproduction in facultatively parthenogenetic populations under sexual conflict: an agent-based simulation

Facultative parthenogenesis is rare in animals, even though its benefits could allow facultatively sexual individuals to outcompete those with obligate reproductive modes. One potential reason for this rarity might be that a facultative strategy is unstable. Previous studies have investigated the evolution of facultative strategies in obligately sexual populations, but the reverse evolution of obligate sex in an asexual population has rarely been investigated. This process could occur in facultative parthenogens, which often form populations consisting solely of parthenogenetically reproducing females, via invasion by males dispersing from mixed-sex populations. However, the chance of successful male invasion might be reduced by (1) female resistance against sexual reproduction, which could suppress the production of sons; (2) the lack of partially isolated demes that could serve as refugia for males, as patchy populations could buffer against local male extinction and thereby increase the chance of male persistence within a metapopulation; and (3) inbreeding, because inbreeding depression could reduce the fitness of sexually produced individuals. Using agent-based models, we investigated the outcome of simulated male invasions into all-female populations. We found that male invasion success was highly dependent on the presence of female resistance: the lower the resistance cost, the more likely resistance was to spread, and the less likely males were to invade, suggesting that sexual conflict might play a role in the persistence of all-female populations. Relative to a fully connected population (single patch), moderate patchiness (four patches) increased the chance for successful male invasion, but high patchiness (25 patches) reduced invasion success due to edge effects favouring the spread of female resistance. Inbreeding slightly reduced the chance for successful male invasion. Overall, populations in which females utilised both sex and parthenogenesis could persist only within a narrow parameter range where the cost of sex balanced the cost of resistance, supporting the hypothesis that facultative parthenogenesis is demographically unstable.