DOI: 10.5061/dryad.wstqjq2pf
title: North American silene trait medians

description: Combinations of correlated floral traits have arisen repeatedly across
 angiosperms through convergent evolution in response to pollinator
 selection to optimize reproduction. While some plant groups exhibit very
 distinct combinations of traits adapted to specific pollinators (so-called
 pollination syndromes), others do not. Determining how floral traits
 diverge across clades and whether floral traits show predictable
 correlations in diverse groups of flowering plants is key to determining
 the extent to which pollinator-mediated selection drives diversification.
 The North American Silene section Physolychnis is an ideal group to
 investigate patterns of floral evolution because it is characterized by
 the evolution of novel red floral color, extensive floral morphological
 variation, polyploidy, and exposure to a novel group of pollinators
 (hummingbirds). We test for correlated patterns of trait evolution that
 would be consistent with convergent responses to selection in the key
 floral traits of color and morphology. We also consider both the role of
 phylogenic distance and geographic overlap in explaining patterns of
 floral trait variation. Inconsistent with phenotypically divergent
 pollination syndromes, we find very little clustering of North American
 Silene into distinct floral morphospace. We also find little evidence that
 phylogenetic history or geographic overlap explain patterns of floral
 diversity in this group. White and pink flowering species show extensive
 phenotypic diversity but are entirely overlapping in morphological
 variation. However, red flowering species have much less phenotypic
 disparity and cluster tightly in floral morphospace. We find that red
 flowering species have evolved floral traits that align with a traditional
 hummingbird syndrome, but that these trait values overlap with several
 white and pink species as well. Our findings support the hypothesis that
 convergent evolution does not always proceed through comparative
 phenotypic divergence, but possibly through sorting of standing ancestral
 variation.
description: We took the medians of the phenotypic ranges recorded in the
 Flora of North America (FNA) and the Jepson eFlora, except when noted, for
 the following traits: stem length, leaves per node, leaf length, calyx
 height, calyx width, and petal limb length. We categorized the following
 traits: inflorescence (one, few 1-3, many &gt;3), floral tube
 extension from calyx (below calyx, equal to calyx, above calyx),
 reproductive organ exsertion (below corolla, equal to corolla, extended
 above corolla). Floral color was assigned into three bins: white, pink,
 and red. Silene species that have white/pink floral color polymorphism
 were generally coded as pink to reflect the ability of the species to
 produce pigment in their petals. The single species that is a pale yellow,
 <em>S. parishii</em>, was coded as white to reflect the
 absence of anthocyanin pigments. The orange-pink <em>S.
 salmonacea</em> was coded as pink. Ploidy information was taken from
 a combination of sources including the FNA and the literature (Kruckeberg,
 1954, Kruckeberg, 1964, Kruckeberg, 1955, Kruckeberg, 1961, Kruckeberg,
 1960, Spellenberg, 1979). Floral characters described
 in the FNA as ratios were calculated from the median value (e.g. “corolla
 11/4 times longer than calyx height”), and were otherwise measured
 manually or an alternate source was sought. For species and traits that
 were not included or calculable in the FNA we used other flora, field
 guides, literature, herbarium measurements, and field measurements, see
 Supplementary Table 5 in the manuscript/journal article.
description: Any software that can open an Excel or comma-delimited file.