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Summary The evolution of tube-like floral morphologies that control pollen release via small openings (functionally poricidal flowers) represents a taxonomically and geographically widespread instance of repeated and independent evolution of a functionally similar morphology. Poricidal flowers are often closely associated with buzz pollination by bees, but we lack an updated angiosperm-wide survey of their phylogenetic distribution.We identify all presently known angiosperm genera containing poricidal flowers via a literature survey. We determined the phylogenetic distribution of poricidal flowers and minimum number of independent gains and losses via a genus-level and species level angiosperm-wide phylogeny. We estimated if evolution of poricidal flowers is associated with changes in speciation/extinction via diversification rate analyses.Poricidal flowers occur across at least 87 angiosperm families and 635 genera containing > 28,000 species. At the genus level, more than 200 independent gains and 145 independent losses of poricidal flowers occurred. Across angiosperms, genus-level analyses suggest poricidal flower evolution is associated with lower net diversification rates (origination-extinction). Species-level analyses argue no diversification linked to poricidal morphology but within the two focal families we found family-specific diversification effects.We present different hypotheses for the functional significance of poricidal flowers, including its association with buzz pollination, and suggest future directions for studies elucidating the extent to which morphological and functional convergence of poricidal flowers are correlated. 

Abstract A fundamental question in evolutionary biology is how clades of organisms exert influence on one another. The evolution of the flower and subsequent plant/pollinator coevolution are major innovations that have operated in flowering plants to promote species radiations at a variety of taxonomic levels in the Neotropics. Here we test the hypothesis that pollination by Neotropical endemic hummingbirds drove the evolution of two unique stigma traits in correlation with other floral traits in New World Salvia (Lamiaceae). We examined morphometric shapes of stigma lobing across 400 Salvia spp., scored presence and absence of a stigma brush across Salvia, and used a suite of phylogenetic comparative methods to detect shape regime shifts, correlation of trait shifts with BayesTraits and phylogenetic generalized least square regressions, and the influence of scored pollinators on trait evolution using OUwie. We found that a major Neotropical clade of Salvia evolved a correlated set of stigma features, with a longer upper stigma lobe and stigmatic brush, following an early shift to hummingbird pollination. Evolutionary constraint is evident as subsequent shifts to bee pollination largely retained these two features. Our results support the hypothesis that hummingbirds guided the correlative shifts in corolla, anther connective, style and stigma shape in Neotropical Salvia, despite repeated shifts back to bee pollination. 

Next-generation sequencing technologies have facilitated new phylogenomic approaches to help clarify previously intractable relationships while simultaneously highlighting the pervasive nature of incongruence within and among genomes that can complicate definitive taxonomic conclusions. Salvia L., with ∼1,000 species, makes up nearly 15% of the species diversity in the mint family and has attracted great interest from biologists across subdisciplines. Despite the great progress that has been achieved in discerning the placement of Salvia within Lamiaceae and in clarifying its infrageneric relationships through plastid, nuclear ribosomal, and nuclear single-copy genes, the incomplete resolution has left open major questions regarding the phylogenetic relationships among and within the subgenera, as well as to what extent the infrageneric relationships differ across genomes. We expanded a previously published anchored hybrid enrichment dataset of 35 exemplars of Salvia to 179 terminals. We also reconstructed nearly complete plastomes for these samples from off-target reads. We used these data to examine the concordance and discordance among the nuclear loci and between the nuclear and plastid genomes in detail, elucidating both broad-scale and species-level relationships within Salvia . We found that despite the widespread gene tree discordance, nuclear phylogenies reconstructed using concatenated, coalescent, and network-based approaches recover a common backbone topology. Moreover, all subgenera, except for Audibertia , are strongly supported as monophyletic in all analyses. The plastome genealogy is largely resolved and is congruent with the nuclear backbone. However, multiple analyses suggest that incomplete lineage sorting does not fully explain the gene tree discordance. Instead, horizontal gene flow has been important in both the deep and more recent history of Salvia . Our results provide a robust species tree of Salvia across phylogenetic scales and genomes. Future comparative analyses in the genus will need to account for the impacts of hybridization/introgression and incomplete lineage sorting in topology and divergence time estimation. 

PremiseWe tested 25 classic and novel hypotheses regarding trait–origin, trait–trait, and trait–environment relationships to account for flora‐wide variation in life history, habit, and especially reproductive traits using a plastid DNA phylogeny of most native (96.6%, or 1494/1547 species) and introduced (87.5%, or 690/789 species) angiosperms in Wisconsin, USA. MethodsWe assembled data on life history, habit, flowering, dispersal, mating system, and occurrence across open/closed/mixed habitats across species in the state phylogeny. We used phylogenetically structured analyses to assess the strength and statistical significance of associations predicted by our models. ResultsIntroduced species are more likely to be annual herbs, occupy open habitats, have large, visually conspicuous, hermaphroditic flowers, and bear passively dispersed seeds. Among native species, hermaphroditism is associated with larger, more conspicuous flowers; monoecy is associated with small, inconspicuous flowers and passive seed dispersal; and dioecy is associated with small, inconspicuous flowers and fleshy fruits. Larger flowers with more conspicuous colors are more common in open habitats, and in understory species flowering under open (spring) canopies; fleshy fruits are more common in closed habitats. Wind pollination may help favor dioecy in open habitats. ConclusionsThese findings support predictions regarding how breeding systems depend on flower size, flower color, and fruit type, and how those traits depend on habitat. This study is the first to combine flora‐wide phylogenies with complete trait databases and phylogenetically structured analyses to provide powerful tests of evolutionary hypotheses about reproductive traits and their variation with geographic source, each other, and environmental conditions.