Trait variation defines and underpins biodiversity, yet we are only beginning to understand how processes acting across biological scales (individuals to whole communities) interact to produce trait differences and their consequences, particularly over short time scales. First, species often differ widely in their mean phenotype, meaning that changes in community composition can alter average trait values of a guild. Second, phenotypic plasticity alters the trait values of individuals, and the net effect of plasticity can also shift the average trait values of a specific species or of whole communities. However, community assembly, phenotypic plasticity, and their effects on biological patterns are not independent. The expression of phenotypic plasticity tends to be species‐specific, meaning that differences in species’ relative abundances will shape trait change and resulting ecological patterns and processes. I test this idea using mesocosms and simulations of communities of dragonfly larvae that differ in activity rate. Some but not all species reduced their activity rate in response to predation risk, causing larger trait‐mediated changes in trophic interactions in experimental communities dominated by plastic versus aplastic species. Using surveys and simulations of natural ponds, I demonstrate that community composition will shape patterns of phenotypic plasticity, with likely consequences for ecological dynamics in the wild. The interactive effects of trait differences across scales of biological organization necessitates an integrated view of diverse biological processes, including plasticity and community assembly, in order to understand ecological interactions.

中文翻译：

---

表型可塑性和群落组成相互作用形成营养相互作用

性状变异定义并支撑着生物多样性，但是我们才刚刚开始理解跨生物尺度（个体到整个社区）的过程如何相互作用以产生特质差异及其后果，特别是在短时间内。首先，物种的平均表型通常差异很大，这意味着社区组成的变化会改变行会的平均性状值。其次，表型可塑性改变了个体的特征值，可塑性的净效应也可以改变特定物种或整个社区的平均特征值。但是，社区大会，表型可塑性及其对生物学模式的影响不是独立的。表型可塑性的表达往往是物种特异性的，意味着物种相对丰度的差异将影响性状变化以及由此产生的生态模式和过程。我使用介观和活动率不同的蜻蜓幼虫群落的模拟来测试这个想法。一些但并非全部物种降低了对捕食风险的响应，从而导致了以塑料和再生障碍性物种为主导的实验群落的营养相互作用中较大的性状介导的变化。通过对天然池塘的调查和模拟，我证明了社区组成将影响表型可塑性的模式，并可能对野生生态动态产生影响。跨生物组织规模的性状差异的交互作用需要对多种生物过程（包括可塑性和群落组装，