Data from: Convergent evolution of floral shape tied to pollinator shifts in Iochrominae (Solanaceae)

Flower form is one of many floral features thought to be shaped by pollinator-mediated selection. Although the drivers of variation in flower shape have often been examined in microevolutionary studies, relatively few have tested the relationship between shape evolution and shifts in pollination system across clades. In the present study, we use morphometric approaches to quantify shape variation across the Andean clade Iochrominae and estimate the relationship between changes in shape and shifts in pollination system using phylogenetic comparative methods. We infer multiple shifts from an ancestral state of narrow, tubular flowers toward open, bowl-shaped or campanulate flowers as well as one reversal to the tubular form. These transitions in flower shape are significantly correlated with changes in pollination system. Specifically, tubular forms tend to be hummingbird-pollinated and the open forms tend to be insect-pollinated, a pattern consistent with experimental work as well as classical floral syndromes. Nonetheless, our study provides one of the few empirical demonstrations of the relationship between flower shape and pollination system at a macroevolutionary scale.

花形是众多被认为由传粉者介导选择塑造的花部特征之一。尽管微进化研究中常探讨花形变异的驱动因素，但跨支系检验花形演化与传粉系统转变之间关联的研究仍相对匮乏。本研究采用形态计量学方法，量化安第斯支系染木亚族（Iochrominae）的花形变异，并通过系统发育比较方法，估算花形变化与传粉系统转变之间的关联。研究推断，该支族的花形演化存在多次从祖先狭管状花，向开放的碗状或钟状（campanulate）花的转变，且存在一次向管状花形态的逆转。这些花形转变与传粉系统的变化存在显著相关性。具体而言，管状花类群多为蜂鸟传粉，而开放花类群多为昆虫传粉，这一模式与实验研究及经典的花综合征（floral syndromes）结果相符。尽管如此，本研究仍是极少数在宏进化尺度上，实证验证花形与传粉系统之间关联的研究之一。