Maternal stress during pregnancy affects activity, exploration and potential dispersal of daughters in an invasive fish

Stress experienced by mothers can affect offspring phenotype, with some of these modifications potentially preparing offspring for the environment they will likely encounter. Many maternal stressors, including encounters with predators, can influence how offspring respond to risk and cues of danger later on. Using the live-bearing, highly invasive western mosquitofish, Gambusia affinis, we examined how repeated brief (<30 s) maternal exposures to a largemouth bass, Micropterus salmoides, model during pregnancy shapes offspring activity in response to cues of predation risk, as well as offspring movement through an artificial stream. Maternal predator exposure tended to increase the activity of daughters, but not sons, in a novel tank with cues of risk. In addition, maternal predator exposure increased the movement of small daughters, but not large daughters, through an artificial stream. Our results suggest that encountering predators during pregnancy can have sex-specific effects on offspring movement and exploration, particularly for sizes that are the most vulnerable to predation. In invasive species, such as mosquitofish, the transgenerational consequences of predation risk for activity, exploration and movement could help us predict potential dispersal patterns and the types of individuals at the invasion front. There are TWO data sets, each associated with a different assay: 1. F1s (sons and daughters) and their activity (i.e. line crosses) in response to three sequential stimuli - novel tank, chemical alarm cue & after being chased by a bass lure 2. F1 daughters only and their exploratory behavior in an artificial stream母本所承受的应激可影响子代的表型，其中部分修饰效应或可帮助子代适应其未来大概率遭遇的生存环境。诸多母本应激源（包括遭遇捕食者）均可影响子代后续对风险与危险信号的响应模式。本研究以胎生且极具入侵性的西部食蚊鱼（Gambusia affinis）为实验材料，探究妊娠期间母本反复短暂（时长<30秒）暴露于以大口黑鲈（Micropterus salmoides）为模型的捕食者环境中，会如何塑造子代面对捕食风险信号时的活动行为，以及子代在人工溪流中的移动能力。母本捕食者暴露处理可提升雌性子代（而非雄性子代）在带有风险信号的新奇水族箱中的活动水平。此外，该处理还可提升小型雌性子代（而非大型雌性子代）在人工溪流中的移动能力。本研究结果表明，妊娠期间遭遇捕食者可对子代的移动与探索行为产生性别特异性影响，尤其对那些捕食风险最高的体型类群。对于食蚊鱼这类入侵物种而言，捕食风险通过跨代传递对子代活动、探索与移动行为产生的效应，或可帮助我们预测其潜在的扩散模式以及入侵前沿的个体类群。 本研究包含两套数据集，分别对应不同的行为测定实验： 1. F1代子代（雄性与雌性）及其面对三种连续刺激时的活动表现（即杂交组合）：新奇水族箱环境、化学警报信号刺激，以及经鲈鱼诱饵追逐后的响应。 2. 仅包含F1代雌性子代及其在人工溪流中的探索行为。