Female pipefish can detect the immune status of their mates

Given the ubiquity of the parasites and their important fitness consequences on mate and offspring condition, selection for the ability to distinguish healthy from parasitized potential mates is a key process to enhance Darwinian fitness. In this study, we experimentally evaluated how the immunological experience of two potential partners influences mate choice, using the sex-role-reversed pipefish Syngnathus typhle. We exposed S. typhle to immune challenges with heat-killed Vibrio bacteria and investigated whether the activation of the immune system determined mate preferences. Our results demonstrate that the immune status of the potential partners influenced female mate preference, such that females that were exposed to an immune challenge became choosy and favored unchallenged males. Males, however, did not show any preferences for female immune status. In this context, we discuss mate choice decisions and behavioral plasticity as a complex result of immune challenge, severity of infection, as well as trans-generational effects.鉴于寄生虫广泛分布，且会对配偶与后代的健康状况产生显著的适合度影响，自然选择青睐区分健康个体与被寄生潜在配偶的能力，这是提升达尔文适合度（Darwinian fitness）的关键过程。本研究以性角色反转的海龙（Syngnathus typhle）为实验对象，通过实验手段探究了两名潜在配偶的免疫经历对配偶选择的影响。我们将试验个体暴露于热灭活弧菌（Vibrio）的免疫刺激环境中，并分析免疫系统激活与否是否会决定配偶偏好。研究结果表明，潜在配偶的免疫状态会影响雌性的配偶选择：经历过免疫刺激的雌性会变得更为挑剔，更倾向于选择未受免疫刺激的雄性。而雄性则未表现出对雌性免疫状态的偏好。在此研究背景下，我们探讨了配偶选择决策与行为可塑性如何作为免疫刺激、感染严重程度以及跨代效应（trans-generational effects）共同作用的复杂结果。