Floral community predicts pollinators' color preference: implications for Batesian floral mimicry

Animals that rely on nectar are expected to display floral trait preferences correlating to the signals of nectar source flowers. Batesian mimicry evolves to exploit these pre-existing signal-receiver relationships, attracting pollinators through an adaptive resemblance to specific co-occurring rewarding species. The nectar-feeding long-proboscid flies of South Africa are pollinators for several deceptive orchid species that are putatively Batesian mimics. We tested whether flies’ measured color preference varied among communities providing different nectar-source diets, which would indicate the necessary signal-receiver conditions for the evolution of advergent Batesian mimicry. We introduced artificial rewardless flowers into flowering communities that supported divergent nectar-diets in resident flies and inferred floral trait preferences of a long-proboscid fly species (Prosoeca ganglbaueri) from visitation behavior to these artificial flowers. The experiment showed that the prefere...

依赖花蜜的动物通常会表现出与蜜源植物信号相关的花部性状偏好。贝茨拟态（Batesian mimicry）的演化正是为了利用这些已存在的信号-接收者关系，通过对特定同域共存的报酬性物种的适应性拟态来吸引传粉者。南非的长吻食蜜蝇类是数种被认为是贝茨拟态的欺骗性兰科植物的传粉者。我们开展实验以检验：在提供不同蜜源饮食的群落中，蝇类实测的颜色偏好是否存在差异——这一差异可表明趋同贝茨拟态（advergent Batesian mimicry）演化所需的信号-接收者条件。我们将无报酬人工花引入到栖息蝇类具有不同蜜源饮食背景的开花群落中，并通过蝇类对这些人工花的访花行为，推断出长吻蝇（Prosoeca ganglbaueri）的花部性状偏好。本实验结果显示，该偏好……