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Premise: The proportion of polyploid plants in a community increases with latitude, and different hypotheses have been proposed about which factors drive this pattern. Here, we aimed to understand the historical causes of the latitudinal polyploidy gradient using a combination of ancestral state reconstruction methods. Specifically, we assessed whether (1) polyploidization enables movement to higher latitudes (i.e., polyploidization precedes occurrences in higher latitudes) or (2) higher latitudes facilitate polyploidization (i.e., occurrence in higher latitudes precedes polyploidization). Methods: We reconstructed the ploidy states and ancestral niches of 1032 angiosperm species at four paleoclimatic time slices ranging from 3.3 million years ago to the present, comprising taxa from four well‐represented clades: Onagraceae, Primulaceae, Solanum (Solanaceae), and Pooideae (Poaceae). We used ancestral niche reconstruction models alongside a customized discrete character evolution model to allow reconstruction of states at specific time slices. Patterns of latitudinal movement were reconstructed and compared in relation to inferred ploidy shifts. Results: No single hypothesis applied equally well across all analyzed clades. While significant differences in median latitudinal occurrence were detected in the largest clade, Poaceae, no significant differences were detected in latitudinal movement in any clade. Conclusions: Our preliminary study is the first to attempt to connect ploidy changes to continuous latitudinal movement, but we cannot favor one hypothesis over another. Given that patterns seem to be clade‐specific, more clades must be analyzed in future studies for generalities to be drawn. [ABSTRACT FROM AUTHOR]

In science, standardization of terminology is crucial to make information accessible and allow proper comparison of studies' results. Climbing plants and the climbing habit have been described in numerous ways, frequently with imprecise and dubious terms. We propose a standardization of terms regarding the climbing habit, with special attention to climbing mechanisms. We abide by previous suggestions that the terms 'primary' and 'secondary' hemiepiphyte be substituted by 'hemiepiphyte' and 'nomadic climber' respectively, thus emphasizing the relationship of the latter to the climbing habit. We also suggest that 'climbing plant' or 'climber' be used to describe plants displaying the climbing habit, and 'liana' and 'vine' be left for describing woody and herbaceous climbers respectively. As for climbing mechanisms, we propose an eight-category classification comprised of two major categories: passive climbing, containing scrambling, hooks or grapnels, and adhesive roots; and active climbing, containing twining, tendrils, prehensile branches, twining petioles, and twining inflorescences. Keywords climbing plants * lianas * vines * climbing mechanisms * standardization * terminology Portuguese Na ciencia, a padronizacao de terminologia e crucial para tomar informacoes acessiveis e possibilitar a comparacao adequada dos resultados de estudos. Trepadeiras e o habito trepador vem sendo descritos de diversas maneiras, frequentemente com termos imprecisos e dubios. Nos propomos urna padronizacao da terminologia relativa ao habito trepador, corn atencao especial aos mecanismos de escalada. Nos acatamos sugestoes anteriores de que os termos 'hemiepifita primaria' e 'secundaria' sejam substituidos por 'hemiepifita' e 'trepadeira nomade' respectivamente, enfatizando assim a relacao desta ultima com o habito trepador. Nos tambem sugerimos que 'trepadeira' seja utilizado para descrever plantas apresentando o habito trepador, e 'liana' e 'trepadeira herbacea' sejam utilizados somente para descrever trepadeiras lenhosas e herbaceas respectivamente. Quanto aos mecanismos de escalada, nos propomos urna classificacao com oito categorias compreendidas em duas grandes categorias: trepadeiras passivas, contendo os mecanismos apoiante, ganchos e raizes grampiformes; e trepadeiras ativas, contendo os mecanismos voluvel, gavinhas, ramos preensores, peciolos voluveis e inflorescencias voluveis. Palavras-chave trepadeiras * lianas * mecanismos de escalada * padronizacao * terminologia, Introduction In an ideal scenario of any biological study, the ternis of scientific language and the concepts they express should be clear and precise to avoid ambiguities, which are a [...]

Premise: Conservation policies typically focus on biodiversity hotspots. An alternative approach involves analyzing the evolutionary history of lineages in geographic areas along with their threat levels to guide conservation efforts. Mountains exhibit high levels of plant species richness and micro‐endemism, and biogeographic studies commonly point to recent and rapid evolutionary radiations in these areas. Using a nearly endemic clade of legumes, our study evaluates conservation prioritization approaches in the campo rupestre, a Neotropical ecosystem associated with mountaintops that is located between two biodiversity hotspots. Methods: We compared the EDGE and EDGE2 metrics, which combine the evolutionary distinctiveness and the extinction risk of a species in a single value. These metrics are compared with traditional metrics used to assess conservation priority, such as phylogenetic diversity. Results: The EDGE values reported are lower than those of other studies using this metric, mostly due to the prevalence of threatened species with short phylogenetic branch lengths (low values of evolutionary distinctiveness). Certain areas of campo rupestre with relatively high phylogenetic diversity and EDGE values do not correspond to areas with high species richness, agreeing with previous studies on biodiversity hotspots. Discussion: Our study highlights the necessity of conservation of the campo rupestres as well as advantages and disadvantages of using EDGE, EDGE2, and phylogenetic diversity for appropriate selection of conservation areas with rapid evolutionary radiations. The selection of the metrics will depend primarily on the life history of the focus group and the data availability, as well as the conservation approach. [ABSTRACT FROM AUTHOR]