not-yet-known not-yet-known not-yet-known unknown No evidence for a female mating status effect on reproductive behavior in the polygamous arachnid Leiobunum vittatum

Unmated, “virgin”, females are frequently preferred by researchers in reproductive animal behavior study designs, with previously mated females often being entirely excluded from samples. Unmated females are assumed to be more responsive and receptive, while mated females may skew results due to difficulties controlling for previous mating experience. Failing to incorporate mated females, however, may yield incomplete or contradictory results. Many mating behavior hypotheses, such as the trade-up and convenience polyandry hypotheses, typically predict behavior to vary significantly with mating status. The trade-up hypothesis predicts that unmated females should readily mate with the first male encountered before becoming less receptive and only subsequently remating with preferred males. Conversely, the convenience polyandry hypothesis predicts that females should become increasingly receptive as male encounters increase due to the high cost of resisting male antagonism. We tested whether mating behavior and female receptivity varied with mating experience using the Opiliones species Leiobunum vittatum (Arachnida). L. vittatum is among the most common opilionids in North America and has lost precopulatory nuptial gifts while evolving morphology indicative of sexual conflict. We conducted successive behavioral assays using juvenile-collected and adult-collected individuals to compare mated and unmated female behavior as well as to assess how intra-individual receptivity varied with mate encounter number. Using a hybrid behavioral analysis incorporating both automated and manual video scoring, we found that prior mating experience did not significantly affect female receptivity or mating behavior. Additionally, increasing male encounters did not significantly affect behavior typically associated with sexual conflict. Collectively, we found no evidence supporting the trade-up or convenience polyandry hypotheses, nor did we find support for assumptions that unmated females better serve as behavioral subjects due to increased responsiveness. Further research is required to determine whether other factors such as social experience, local adaptation, or postcopulatory paternity biasing may be modulating mating behavior in the species.