Mating status-dependent "choice" in competitive and noncompetitive arenas.

Abstract

To maximize their reproductive fitness, females of many polyandrous species should display mating status-dependent choice, where they mate relatively indiscriminately once to ensure reproductive output, and then become choosy and mate preferentially with higher-quality males. Despite this potential contrast in choosiness, most mate choice experiments use virgin females. Here, using a panel of 20 isofemale strains that originated from wild-caught flies, we allowed virgin and non-virgin Drosophila melanogaster females to choose among males from the same panel of strains. We used single-male latency trials and a series of male competition trials to help disentangle female "choices" from male-male competitive effects. Most virgin females mated within 2 h of males being introduced, compared with fewer than half of non-virgin females mating over the same period. However, despite mating more rapidly, virgin females did not mate indiscriminately, and their "choices" strongly aligned with those of previously mated females across both the single-male latency and male-male competition trials. Our results challenge the idea that virgin females mate relatively indiscriminately and show that female choice may be more stable than is generally appreciated.