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Lineage‐specific traits determine how plants interact with their surrounding environment. Unrelated species may evolve similar phenotypic characteristics to tolerate, persist in, and invade environments with certain characteristics, resulting in some traits becoming relatively more common in certain types of habitats. Analyses of these general patterns of geographical trait distribution have led to the proposal of general principles to explain how plants diversify in space over time. Trait–environment correlation analyses quantify to what extent unrelated lineages have similar evolutionary responses to a given type of habitat. In this synthesis, I give a short historical overview on trait–environment correlation analyses, from some key observations from classic naturalists to modern approaches using trait evolution models, large phylogenies, and massive data sets of traits and distributions. I discuss some limitations of modern approaches, including the need for more realistic models, the lack of data from tropical areas, and the necessary focus on trait scoring that goes beyond macromorphology. Overcoming these limitations will allow the field to explore new questions related to trait lability and niche evolution and to better identify generalities and exceptions in how plants diversify in space over time. [ABSTRACT FROM AUTHOR]

• A novel multilocus and highly supported phylogeny clarify several previously uncertain relationships in Myrcia. • Our results provide a solid backbone for further evolutionary and taxonomic work. • Previously unplaced Myrcia species formed a new circumscribed clade. • The first phylogenetic relationships for Myrcia sect. Gomidesia are shown with a morphological trait evolution and geographic range distribution approaches. • The inclusion of previously available molecular data with novel sequences of Myrcia and relatives significantly improved our phylogenetic estimates. Myrcia is the largest exclusively Neotropical genus of the plant family Myrtaceae with c. 770 species. Although several studies have elucidated the relationships within particular sections of the genus, to date no phylogeny has been produced that includes a broad taxonomic and geographic representation. Here we present a phylogenetic hypothesis of Myrcia and close relatives comprising 253 species and based on two nuclear and seven plastid markers. We combine previously available sequence data with 234 new sequences of the genus Myrcia for this study. We use this phylogeny to investigate the evolution of selected morphological traits and to infer the biogeographic history of the genus. Our results yield a highly supported phylogenetic tree where the Myrceugenia group is sister to the Myrcia and Plinia groups. Five Myrcia species previously considered unplaced emerge in a newly circumscribed clade. The monophyly of two Myrcia sections previously considered uncertain, Aulomyrcia and Gomidesia, are confirmed with strong support. Flowers with free calyx lobes, 2-locular ovaries, and anthers with symmetrical thecae are ancestral features of Myrcia. The Myrcia sect. Gomidesia is highly supported and recovered as monophyletic, with asymmetric anthers that retain their curvature after dehiscence as a morphological synapomorphy. The Atlantic Forest is the most likely ancestral area of the genus and most of its internal clades, from where multiple lineages colonized different regions of South and Central America, in particular the Brazilian Cerrado through multiple unidirectional range expansions. The southern Atlantic Forest is the ancestral area for Myrcia sect. Gomidesia , with lineages reaching the northern Atlantic Forest, Cerrado, Yungas, and other savanna vegetation of South America. Our results provide a solid backbone for further evolutionary and taxonomic work and clarify several previously uncertain relationships in this mega-diverse plant group, and shed light on its geographical range evolution. [ABSTRACT FROM AUTHOR]

Premise of research. The opening of the Drake Passage in the Miocene (disconnecting Antarctica and South America and resulting in the establishment of the Circumpolar Current preventing warm waters from the north to reach the polar continent) has led to the formation of the ice sheets and the retreat of the temperate to tropical vegetation that had covered Antarctica for millions of years. With only two current native vascular plant species, Antarctica has been virtually ignored in biogeographical reconstructions and, when considered, only a posteriori invoked as a route of dispersal to reconcile inferred disjunct biogeographical patterns. Methodology. Here, we provide a brief overview of the rich fossil record of Antarctica, further confirming that many plant families were once present on this continent and that the age of a family is mostly not correlated with its presence or absence on the continent. Such evidence indicates a need to develop a paleogeographical model incorporating Antarctica that can be applied to constrain ancestral area reconstructions. We propose such a model and investigate its effects on biogeographical scenarios using the cosmopolitan plant family Myrtaceae (a family with a rich fossil record in Antarctica) as a case study. Pivotal results. Based on this evidence and previous studies that have shown the importance of Antarctica in the biogeography and evolution of plant lineages, we argue that this region should routinely be included as a predefined area in biogeographical analyses. Conclusions. A possible paleogeographical model including Antarctica is proposed. It is subdivided into five time slices and spans the last 160 Myr. We expect that the formal inclusion of Antarctica in ancestral area reconstructions (using an evidence-based biogeographical model) will open further discussions and research programs assessing the importance of this area in shaping the current temperate and tropical floras and increase the precision of resulting biogeographical patterns. [ABSTRACT FROM AUTHOR]

• Tapinotaspidini broad phylogeny indicates monophyly of most genera. • Tapinotaspidini bees originated in Cerrado-like savannas in the Paleocene. • Transitions to forested areas slightly increase speciation rates. • Malpighiaceae is the ancestral host for floral oils. • Shifts to other oil plant families are possibly linked to habitat shifts. Worldwide distributed tropical savannas were established only in the Miocene, with climatic cooling and rise of C4 grasses. However, there is evidence for an earlier presence of savanna-like vegetation in southern parts of South America. Here we investigated the biogeographic history of a clade of solitary bees which have endemic groups in areas covered by savannas and other types of open vegetation as well as forested areas. We hypothesized that these bees originated in savanna-like biomes and that shifts to forested areas and floral host shifts increased species diversification along their evolutionary history. We reconstructed a comprehensive phylogeny for Tapinotaspidini bees based majorly on original DNA sequences. We then used macroevolutionary tools to estimate ancestral range area and reconstructed ancestral habitat (open versus forested) and host plant association to analyze the effects of shifts in vegetation type and flower hosts on their diversification. Tapinotaspidini bees originated in the Paleocene and in a savanna-type, Cerrado-like, which is reinforced by reconstruction of open vegetation as the most probable ancestral area, thus bringing additional evidence to a much earlier origin of this vegetation type in South America. Shifts to forested areas occurred at least three times in a period of 30 Ma and were responsible for slight increases in diversification rates. Malpighiaceae is the ancestral floral host; host broadening occurred only in the Miocene and at least in three occasions. Host shifts, i.e. from Malpighiaceae to other oil families, occurred in the Eocene and Miocene. Both host broadening and host shifts did not significantly alter diversification rates, however exploitation of other oil sources were important in occupying new habitats. The link between biomes and host plant shifts and changes in diversification rate brings us additional insights into the evolution of bees and associated flora in South America. [ABSTRACT FROM AUTHOR]