<b>Sex-driven neighborhood effects on herbivory in the dioecious Mediterranean palm </b><b><i>Chamaerops humilis</i></b><b> L.</b>

Although it is well recognized that the strength of plant-herbivore interactions can vary with plant sex and the distance and density of conspecific neighbors, no study has yet assessed their combined influence. Here, we filled this knowledge gap by focusing on the dioecious palm <i>Chamaerops humilis</i> L., and its two main herbivores, the invasive moth <i>Paysandisia archon</i> Burmeister and the feral goat <i>Capra hircu</i>s L. We evaluated levels and spatial patterns of herbivory, as well as those of plant size and the number of inflorescences in two palm populations in Mallorca (Balearic Islands, Spain). Our spatial point pattern analyses revealed that palms not affected by moth herbivory or goat florivory were spatially aggregated, goats fed more strongly upon inflorescences in palms with more neighbors but they consumed more leaves in isolated palms. Interestingly, we could reveal for the first time that plant sex is a key plant trait modulating neighborhood effects. For instance, whereas aggregated female palms experienced lower intensity of goat florivory than isolated ones, male palms showed the opposite pattern. Palm size and the number of inflorescences also showed sex-related differences, suggesting that sexual dimorphism is a key driver of the observed neighborhood effects on herbivory. Our study highlights the importance of considering relevant plant traits such as sex when investigating plant neighborhood effects, calling for further research to fully understand the dynamics governing plant-herbivore interactions in dioecious systems.尽管学界已明确，植物-草食动物互作的强度会随植物性别、同种邻体的距离与密度发生变化，但目前尚无研究评估这三者的共同影响。本研究以雌雄异株棕榈欧洲矮棕（*Chamaerops humilis* L.）及其两种主要草食类天敌——入侵性蛾类枣椰潜蛾（*Paysandisia archon* Burmeister）与野化家山羊（*Capra hircus* L.）为研究对象，填补了这一研究空白。我们在西班牙巴利阿里群岛马略卡岛的两个棕榈种群中，对草食危害程度与空间格局、植株大小及花序数量开展了调查与评估。空间点格局分析结果显示：未受蛾类草食危害或山羊花食危害的棕榈个体呈空间聚集分布；山羊对邻体更多的棕榈的花序取食强度更高，而对孤立棕榈个体则更多取食叶片。值得关注的是，本研究首次揭示植物性别是调控邻体效应的关键植物性状：例如，聚集分布的雌性棕榈相较于孤立个体，受到山羊花食危害的强度更低，而雄性棕榈则呈现完全相反的模式。棕榈植株大小与花序数量同样存在性别相关差异，这表明有性二态性是驱动草食危害邻体效应产生的关键因素。本研究强调，在探究植物邻体效应时，需纳入植物性别这类相关功能性状进行考量，并呼吁开展更多研究以全面阐明雌雄异株系统中植物-草食动物互作的动态调控机制。