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PREMISE: Under pollinator limitations, specialized pollination syndromes may evolve toward contrasting responses: a generalized syndrome with increased pollinator attraction, pollinator reward, and pollen transfer capacity; or the selfing syndrome with increased self-pollen deposition, but reduced pollinator attraction and pollen transfer capacity. The buzz-pollination syndrome is specialized to explore female vibrating bees as pollinators. However, vibrating bees become less-active pollinators at montane areas of the Atlantic Forest (AF) domain. This study investigated whether the specialized buzz-pollination syndrome would evolve toward an alternative floral syndrome in montane areas of the AF domain, considering a generalized and the selfing syndromes as alternative responses. METHODS: We utilized a lineage within the buzz-pollinated Miconia as study system, contrasting floral traits between montane AF-endemic and non-endemic species. We measured and validated floral traits that were proxies for pollinator attraction, reward access, pollen transfer capacity, and self-pollen deposition. We inferred the evolution of floral trait via phylogenetic comparative methods. RESULTS: AF-endemic species have selectively evolved greater reward access and more frequently had generalist pollination. Nonetheless, AF-endemic species also have selectively evolved toward lower pollen transfer capacity and greater self pollination. These patterns indicated a complex evolutionary process that has jointly favored a generalized and the selfing syndromes. CONCLUSIONS: The buzz pollination syndrome can undergo an evolutionary disruption in montane areas of the AF domain. This floral syndrome is likely more labile than often assumed, allowing buzz-pollinated plants to reproduce in environments where vibrating bees are less-reliable pollinators.

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Abstract: We briefly describe selected results from our thematic project focused on the biodiversity of the Atlantic Forest ("AF BIOTA"), which was jointly funded by FAPESP's BIOTA Program, the U.S. National Science Foundation Dimensions of Biodiversity Program, and the National Aeronautics and Space Administration (NASA). As one of the five most important hotspots of biodiversity in the world, the Atlantic Forest (AF) holds less than 16% of its vegetation cover, yet, amongst the hotspots, it still harbors one of the highest numbers of species, including endemics. By gathering specialists across multiple disciplines (biology, geology, engineering), we aimed to understand how this megabiodiversity was built through time, informing biodiversity science and conservation. Among the results, we trained 18 Master's and 26 Ph.D. students, published more than 400 peer-reviewed papers that improved our knowledge about the forest's biologic and climatic diversity and dynamics through time, developed new analytical methods, produced outreach videos and articles, and provided data to help define biodiversity conservation policies.

Resumo: Descrevemos de forma resumida resultados selecionados do nosso projeto temático com foco na biodiversidade da Floresta Atlântica ("AF BIOTA"), que foi financiado pelo BIOTA FAPESP e pelo programa "Dimensions of Biodiversity" da "U.S. National Science Foundation" e "National Aeronautics and Space Administration" (NASA). Devido à sua megabiodiversidade (que inclui várias espécies endêmicas), e por restar menos de 16% da vegetação original, a Floresta Atlântica (FA) é uma das cinco áreas mais importantes para a biodiversidade do planeta ("biodiversity hotspot"). Reunimos especialistas de diversas disciplinas (biologia, geologia, engenharia) visando compreender como essa megabiodiversidade evoluiu ao longo do tempo e fornecer informações científicas para a sua conservação. Dentre os resultados obtidos, nós formamos 18 mestres e 26 doutores, publicamos mais de 400 artigos científicos que aumentaram o conhecimento sobre a diversidade biológica e climática da FA e sua dinâmica ao longo do tempo, desenvolvemos novos métodos analíticos, produzimos material de divulgação científica e fornecemos dados para desenvolver políticas públicas de conservação da biodiversidade.

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Several centers of endemism have been proposed for Melastomataceae, particularly in Amazonia and Atlantic Forest. Despite the high degree of human-caused degradation in the last 500 years, the Atlantic Forest still presents some of the largest levels of diversity and endemism across all angiosperms. With several recently described species in the last decade, the knowledge on Bertolonia's distribution and morphological characterization has changed, with most new species found in northern Atlantic Forest and with different flower color patterns than the species from southern Atlantic Forest. We first tested the monophyly of the genus sampling over 85% of its species to generate a reliable phylogenetic hypothesis. Afterwards, we used Bertolonia as a model group to study distribution patterns and morphological evolution of lineages in the Atlantic Forest. Bertolonia is particularly interesting to address such questions because it is endemic to this domain, with species distributed either in the southern, central or northern portions of the Atlantic Forest. The second step of our work aimed to respond (1) Do closely related species endemic to Atlantic Forest tend to have similar distributions and share similar morphological traits? and (2) Are floral traits more conserved within clades than vegetative characters? We hypothesize that both (1) and (2) are true due to the low dispersal ability and consequent microendemic distribution of most species in the genus. Our results confirm the veracity of the proposed hypotheses. Three major groups were recovered in our analysis: marmorata, formosa and nymphaeifolia clades. Most species that occur in northern Atlantic Forest were recovered in the marmorata clade. Most species distributed in central Atlantic Forest were recovered in the formosa clade, and the ones from the southern Atlantic Forest in the nymphaeifolia clade. A similar pattern was recovered with reproductive characters reconstructed across the phylogeny. Generally, species with pink petals and cream-colored anthers with an extrorse pore occur in northern Atlantic Forest, and species with white petals and yellow anthers with an introrse or apical pore tend to occur in southern Atlantic Forest. Some vegetative characters also have evolutionary congruence and are restricted to one or few lineages, while other characters, such as the texture of the leaf blade surface, have a strong taxonomic value and are useful to identify species, but are not homologous. Our analysis also indicates that the division between southern and northern Atlantic Forest could also be related to ancient events, not only linked with recent phylogeographic patterns. Moreover, we suggest that the orientation of the anther pore in Bertolonia could be related with diversity of species and stability of its populations. In summary, we corroborate, based on the evolutionary history of Bertolonia, that closely related species endemic to Atlantic Forest tend to have similar distributions and share similar morphological floral traits.

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We describe Miconia lucenae R.Goldenb. & Michelang., a new species from the montane Atlantic Forest in Santa Teresa in the state of Espírito Santo. Our analysis, based on three plastid spacers (atpF-atpH, psbK-psbl and trnS-trnG), one plastid gene (ndhF, not available for M. lucenae), and two nuclear ribosomal loci (nrITS and nrETS), showed that it belongs to a small clade with Miconia paradoxa (Mart. ex DC.) Triana (Minas Gerais) and M. michelangeliana R.Goldenb. & L.Kollmann (Espírito Santo). The three species in the "Paradoxa clade" can be recognized by the plants with glabrous or glabrescent branches and leaves, white petals and yellow stamens, these with the connectives not prolonged below the thecae, ventrally unappendaged, dorsally unappendaged or with a minute tooth, the latter bilobed or not, glabrous ovary, and the fruits with a persistent calyx. Miconia lucenae can be recognized, among the species in this clade, by the shrubby plants with terete young branches, short inflorescences, usually with red axes, and the 2-bracteolate, sessile, 4-merous flowers, with a ciliolate inner portion of the sepals, lanceolate petals, and 4-celled ovaries. This species can be considered as endangered according to IUCN criteria.

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The systematics of Tryssophyton, herbs endemic to the Pakaraima Mountains of western Guyana, is reviewed and Tryssophyton quadrifolius K.Wurdack & Michelang., sp. nov. from the summit of Kamakusa Mountain is described as the second species in the genus. The new species is distinguished from its closest relative, Tryssophyton merumense, by striking vegetative differences, including number of leaves per stem and leaf architecture. A phylogenetic analysis of sequence data from three plastid loci and Melastomataceae-wide taxon sampling is presented. The two species of Tryssophyton are recovered as monophyletic and associated with mostly Old World tribe Sonerileae. Fruit, seed and leaf morphology are described for the first time, biogeography is discussed and both species are illustrated.

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Recent debates on the number of plant species in the vast lowland rain forests of the Amazon have been based largely on model estimates, neglecting published checklists based on verified voucher data. Here we collate taxonomically verified checklists to present a list of seed plant species from lowland Amazon rain forests. Our list comprises 14,003 species, of which 6,727 are trees. These figures are similar to estimates derived from nonparametric ecological models, but they contrast strongly with predictions of much higher tree diversity derived from parametric models. Based on the known proportion of tree species in neotropical lowland rain forest communities as measured in complete plot censuses, and on overall estimates of seed plant diversity in Brazil and in the neotropics in general, it is more likely that tree diversity in the Amazon is closer to the lower estimates derived from nonparametric models. Much remains unknown about Amazonian plant diversity, but this taxonomically verified dataset provides a valid starting point for macroecological and evolutionary studies aimed at understanding the origin, evolution, and ecology of the exceptional biodiversity of Amazonian forests.

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Miconia papillosperma, a new species of Melastomataceae shrubs from Northern Brazil is described and illustrated. This new species is characterized by elliptic lanceolate leaves with the only pair of secondary veins running close to the margin. It is also unique in having seeds with a papillose testa, a character until now unknown in the Miconieae. The description of this new species from a relatively well collected area near a major road north of Manaus, Amazonas, Brazil, is further evidence of our lack of knowledge on plants in many Neotropical areas.

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Three new species of Angiosperms have been found in four short collection trips to the same protected reserve-"Estação Ecológica Estadual de Wenceslau Guimarães"-and neighboring areas in the Atlantic Forest in the south of the Brazilian state of Bahia. These new species belong to three genera from three distinct lineages in the family Melastomataceae: Huberia, Meriania and Physeterostemon. The description of these species represent a good example of a Linnean shortfall, i.e., the absence of basic knowledge about the biodiversity in the area, as well as in tropical forests as a whole. The description of these probably endemic species per se is a signal that this area deserves more attention regarding research and policies, but its consequences go farther: this area has a relevant role as a phylogenetic (both genetic and morphological) stock, and thus is also valuable as a phylogenetic conservation priority.

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Phylogenetic studies in Melastomataceae have demonstrated the need for taxonomic rearrangements in the current classification. Nonetheless, melastomes are among the most diverse groups of plants and several cases of known artificial taxa have been observed and awaiting further resolution. The Leandra s.str. clade, with ca. 200 species, includes the majority of the taxa traditionally treated in the genus Leandra and is almost restricted to eastern Brazil. In earlier studies, some attempts have been made to infer the relationships within Leandra s.str., but the sampling was sparse and the resolution low inside the clade. Here, we attempt to provide an improved phylogenetic hypothesis for this group on which to base further studies. Specifically, we provide a comprehensive taxon sampling and attempt to infer a species tree for this group, dissecting potential noise in the phylogenetic reconstruction, such as paralogy, rogue taxa, hybridization and incomplete lineage sorting. Our data set includes 126 ingroup species (192 terminals) and four partitions (six markers). We implement the (∗)BEAST model for species tree inference and perform several simulation methods to assess model fit and to discuss potential causes for the observed patterns. Major lineages of Leandra s.str. were delineated, a strictly bifurcating species tree model seems to not account for the observed data, and hybridization is very likely an important evolutionary force in this group.

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Helicobacter pylori seems universally distributed in all human populations, with high prevalence in the third world. Because H. pylori is an ancestral indigenous microbe of the human stomach, we hypothesized that its prevalence in isolated Amerindians would be high. A serologic study was performed on 19 Guahibo-Piaroa and 17 Warao in Venezuela, using H. pylori whole cell (WC) and CagA antigens from US strains. For Guahibo-Piaroa Amerindians, CagA seropositivity was 95%, but WC seropositivity was only 74%. For Warao, both CagA and WC seropositive proportions were low (65% and 76%, respectively). Because all CagA-seropositive individuals carry H. pylori, the results suggest that there has been bacterial antigen divergence, probably caused by genetic drift/natural selection, on humans and their microbes in isolated human groups.

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