Data from: An ultraviolet floral polymorphism associated with life history drives pollinator discrimination in Mimulus guttatus (Phrymaceae)

Premise of the study: Ultraviolet (UV) floral patterns are common in angiosperms and mediate pollinator attraction, efficiency, and constancy. UV patterns may vary within species, yet are cryptic to human observers. Thus, few studies have explicitly described the distribution or ecological significance of intraspecific variation in UV floral patterning. Here, we describe the geographic distribution and pattern of inheritance of a UV polymorphism in the model plant species Mimulus guttatus (Phrymaceae). We then test whether naturally occurring UV phenotypes influence pollinator interactions within M. guttatus. Methods: We document UV patterns in 18 annual and 19 perennial populations and test whether UV pattern is associated with life history. To examine the pattern of inheritance, we conducted crosses within and between UV phenotypes. Finally, we tested whether bee pollinators discriminate among naturally occurring UV phenotypes in two settings: wild bee communities and captive Bombus impatiens. Key results: Within M. guttatus, perennial populations exhibit a small bulls-eye pattern, whereas a bilaterally symmetric runway pattern occurs mainly in annual populations. Inheritance of UV patterning is consistent with a single-locus Mendelian model in which the runway phenotype is dominant. Bee pollinators discriminate against unfamiliar UV patterns in both natural and controlled settings. Conclusions: We describe a widespread UV polymorphism associated with life history divergence within Mimulus guttatus. UV pattern influences pollinator visitation and should be considered when estimating reproductive barriers between life history ecotypes. This work develops a new system to investigate the ecology and evolution of UV floral patterning in a species with extensive genomic resources.研究背景：紫外（Ultraviolet，UV）花斑在被子植物中广泛存在，可介导传粉者的吸引、访花效率及访花专一性。同一物种内的UV花斑可能存在变异，但此类变异对人类观察者而言是隐蔽的。因此，鲜有研究明确阐述种内UV花斑变异的分布格局及其生态学意义。本研究以模式植物沟酸浆（Mimulus guttatus，透骨草科Phrymaceae）为对象，描述其UV花斑多态性的地理分布与遗传模式，并检验自然存在的UV花斑表型是否会影响沟酸浆内的传粉者互作。 研究方法：我们对18个一年生种群和19个多年生种群的UV花斑进行了记录，并检验UV花斑是否与生活史类型相关。为解析遗传模式，我们在不同UV花斑表型之间及同种表型内开展了杂交实验。最后，我们在两种场景下检验了蜂类传粉者是否会区分自然存在的UV花斑表型：野生蜂群落与人工饲养的北美熊蜂（Bombus impatiens）。 主要研究结果：沟酸浆的多年生种群呈现小型靶心型UV花斑，而一年生种群则主要表现为两侧对称的跑道型UV花斑。UV花斑的遗传模式符合单基因孟德尔遗传模型，其中跑道型表型为显性。在自然与受控实验场景中，蜂类传粉者均会规避不熟悉的UV花斑表型。 研究结论：我们阐明了沟酸浆内一类与生活史分化相关的广泛分布的UV花斑多态性。UV花斑会影响传粉者的访花行为，在估算不同生活史生态型间的生殖隔离时应将其纳入考量。本研究构建了全新的研究体系，可用于探究具备丰富基因组学资源的物种中UV花斑的生态学与进化机制。