Department of Botany, Rhodes University, Grahamstown, 6140, South Africa.
Evolution. 2022 Aug;76(8):1749-1761. doi: 10.1111/evo.14540. Epub 2022 Jul 3.
Numerous studies have identified traits associated with anther mimicry; however, the processes underlying floral deception remain poorly documented for these structures. We studied the importance of pollinator attraction and mechanical fit of anther mimics in Tritonia laxifolia (Iridaceae) and their relative contributions to reproductive success. To determine anther mimics role in attraction, we offered bees' binary choices to flowers painted with UV-absorbent and UV-reflecting paints. We also conducted preference experiments between flowers with excised anther mimics and unmanipulated controls, from which mechanical fit was assessed by allowing single visits. Anther mimics' effects on female reproductive success were determined using similar treatments, but on rooted plants. Bees preferred UV-absorbent over UV-reflecting anther mimics. Bees did not discriminate between flowers with and without three-dimensional anther mimics. Single visits resulted in more pollen deposition on unmanipulated controls over flowers with their anther mimics excised, which was directly linked to pollen-collecting behavior. Controls with unmanipulated anther mimics had higher seed set than those with their anther mimics excised. This study provides insights into pollinator-mediated selection on deceptive floral signals and shows that three-dimensional anther mimics increases reproductive success through both attraction and pollen-collecting behaviors.
许多研究已经确定了与花药模拟相关的特征;然而,对于这些结构,花部欺骗背后的过程仍然记录甚少。我们研究了 Tritonia laxifolia(鸢尾科)中花药模拟物对传粉者吸引力和机械适配的重要性,以及它们对繁殖成功的相对贡献。为了确定花药模拟物在吸引中的作用,我们用紫外线吸收和紫外线反射涂料给蜜蜂提供了二元选择的花朵。我们还在带有切除的花药模拟物的花朵和未处理的对照之间进行了偏好实验,通过允许单次访问来评估机械适配。通过类似的处理,但在生根植物上,确定了花药模拟物对雌性繁殖成功的影响。蜜蜂更喜欢紫外线吸收型的花药模拟物,而不是紫外线反射型的花药模拟物。蜜蜂没有在有和没有三维花药模拟物的花朵之间进行区分。单次访问导致未处理的对照上的花粉沉积量多于切除了花药模拟物的花朵,这与花粉收集行为直接相关。未处理的花药模拟物对照的种子结出率高于切除了花药模拟物的对照。本研究深入了解了传粉媒介对欺骗性花部信号的选择,并表明三维花药模拟物通过吸引和花粉收集行为增加了繁殖成功。