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Among nectarivorous birds, the highest niche partitioning occurs between hummingbirds and plants. Although hummingbirds tend to visit morphologically well-matched resources, as ornithophilous species, they can also visit flowers with other traits. Here, we investigated whether the niche partitioning in hummingbird-plant interactions is also observed with ornithophilous species only. We also explored if hummingbird traits predicted resources use. We recorded a plant-ornithophilous species network in a semi-deciduous forest in Brazil. We quantified interaction partitioning through network connectance, complementary specialisation, and modularity. The influence of hummingbirds’ traits into their visits was investigated through methods of functional ecology and ecological networks. We recorded 948 interactions between nine hummingbirds and seven ornithophilous plants. We detected similar patterns of niche partitioning between hummingbirds and ornithophilous plants in comparison to networks considering the entire plant community. However, hummingbird species with the most specialised interactions are different from those when the whole system is evaluated. Therefore, we cannot downscale the patterns from one scale to the other. The pattern of interaction with ornithophilous plants was not related to hummingbirds’ traits. Therefore, the coexistence of species with shared traits might be occurring through facilitative and competitive processes, leading to trait mismatching and maintaining niche partitioning among ornithophilous plants.

Made available in DSpace on 2020-12-12T02:34:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Anthropogenic activities are the main cause of habitat loss and fragmentation, which directly affects biodiversity. Disruption in landscape connectivity among populations may affect complex interactions between species and ecosystem functions, such as pollination and seed dispersal, and ultimately result in secondary extinctions. Urbanization, one of the most intense forms of landscapes changes, has been reported to negatively affect bird and plant diversity. Still, little is known about the effects of urban landscapes on interaction networks. We investigated the relationship between urban landscape structure and plant-frugivore networks at different spatial scales. Coupling interaction data from urban areas and a model selection approach, we evaluated which landscape factors best explained the variation in urban networks properties. Our results indicate that urbanization decreases bird richness, mainly through the loss of habitat specialist species, which results in networks being composed mainly of birds well adapted to urban dwelling. We found that interaction evenness, a measure of homogeneity of interaction distribution between species, increases with urbanization. This is due to the strong dominance that generalist birds had in network composition because they foraged on all available fruits, including exotic plants. The ensuing homogenization of interactions can reduce the resilience of networks and affect the efficiency of ecosystems functions. Thus, urbanization plans should consider the proportion and distribution of green areas within cities, coupling human and ecosystem wellbeing. Programa de Pós-Graduação em Ecologia e Conservação Universidade Federal do Paraná. Centro Politécnico Jardim das Américas Laboratório de Interações & Biologia Reprodutiva Universidade Federal do Paraná. Centro Politécnico Jardim das Américas Departamento de Biologia Faculdade de filosofia ciências e letras de Ribeirão Preto Universidade de São Paulo FFCLRP-USP Ribeirão Preto Universidad de Buenos Aires Facultad de Agronomía Cátedra de Botánica General Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Laboratório de Ecologia Vegetal Universidade Federal do Paraná. Centro Politécnico Jardim das Américas Programa de Pós-Graduação em Ciências Florestais Universidade Federal do Paraná. Jardim Botânico Laboratório de Ecologia Espacial e Conservação (LEEC) Departamento de Ecologia. Universidade Estadual Paulista UNESP Laboratório de Ecologia Espacial e Conservação (LEEC) Departamento de Ecologia. Universidade Estadual Paulista UNESP CNPq: 309453/2013-5 CNPq: 313801/2017-7 CNPq: 445405/2014-7

Backgrounds and AimsTropical plant species are already suffering the effects of climate change and projections warn of even greater changes in the following decades. Of particular concern are alterations in flowering phenology, given that it is considered a fitness trait, part of plant species ecological niche, with potential cascade effects in plant–pollinator interactions. The aim of the study was to assess the potential impacts of climate change on the geographical distribution and flowering phenology of hummingbird-pollinated plants.MethodsWe implemented ecological niche modelling (ENM) to investigate the potential impacts of different climate change scenarios on the geographical distribution and flowering phenology of 62 hummingbird-pollinated plant species in the Brazilian Atlantic Forest.Key ResultsDistribution models indicate future changes in the climatic suitability of their current habitats, suggesting a tendency towards discontinuity, reduction and spatial displacement. Flowering models indicate that climate can influence species phenology in different ways: some species may experience increased flowering suitability whereas others may suffer decreased suitability.ConclusionsOur results suggest that hummingbird-pollinated species are prone to changes in their geographical distribution and flowering under different climate scenarios. Such variation may impact the community structure of ecological networks and reproductive success of tropical plants in the near future.

One of the major challenges in ecology is to understand the relative importance of neutral- and niche-based processes structuring species interactions within communities. The concept of neutral-based processes posits that network structure is a result of interactions between species based on their abundance. On the other hand, niche-based processes presume that network structure is shaped by constraints to interactions. Here, we evaluated the relative importance of neutral-based process, represented by species' abundance (A) and fruit production (F) models, and niche-based process, represented by spatial overlap (S), temporal overlap (T) and morphological barrier (M) models, in shaping the structure of a bird-seed dispersal network from the Brazilian Atlantic Forest. We evaluated the ability of each model, singly or in combination, to predict the general structure [represented by connectance, nestedness (NODF), weight nestedness (WNODF), interaction evenness and complementary specialization] and microstructure of the network (i.e., the frequency of pairwise interactions). Only nestedness (both NODF and WNODF) was predicted by at least one model. NODF and WNODF were predicted by a neutral-based process (A), by a combination of niche-based processes (ST and STM) and by both neutral- and niche-based processes (AM). NODF was also predicted by F and FM model. Regarding microstructure, temporal overlap (T) was the most parsimonious model able to predict it. Our findings reveal that a combination of neutral- and niche-based processes is a good predictor of the general structure (NODF and WNODF) of the bird-seed dispersal network and a niche-based process is the best predictor of the network's microstructure.

O estabelecimento das interacoes planta-polinizador e de grande importância para o funcionamento dos ecossistemas. Estas interacoes podem ser registradas diretamente, por observacao focal, ou indiretamente, pela carga polinica presente no corpo do polinizador. Assim, a avaliacao da especializacao e da dependencia de parceiros mutualisticos, propriedades que podem ser estudadas por meio de redes complexas, depende do metodo empregado no registro das interacoes. O principal objetivo deste estudo foi comparar uma rede de visitacao floral e uma rede de transporte de polen construidas a partir de interacoes entre plantas e abelhas amostradas em 16 parcelas em estagios iniciais de sucessao ecologica na Floresta Atlântica, em Antonina, Parana, sul do Brasil. O registro das interacoes foi realizado inicialmente por observacao focal, e posteriormente foram amostrados os graos de polen aderidos ao corpo de seis especies de abelha, ficando as duas redes restritas as interacoes realizadas por estas seis especies. A rede de transporte de polen foi subdividida em uma rede de alimentacao, utilizando apenas o polen aderido as corbiculas ou escopas das abelhas, e uma rede de polinizacao, com o polen presente no corpo, exceto pernas, das abelhas. Estas redes foram comparadas em relacao ao grau ( k ), ao indice de especializacao ( d’ ) e a forca das especies ( F ), por meio de testes t pareados. A rede de transporte de polen apresentou maior numero de interacoes, maior k , menor d’ e maior numero de especies de planta que a rede de visitacao floral. Nao houve variacao da F. As redes de alimentacao e de polinizacao apresentaram propriedades semelhantes. A analise polinica revelou que as abelhas tendem a realizar turnos de forrageio exclusivos em flores de polen. As interacoes adicionadas a partir da analise polinica resultaram em diferencas nas metricas avaliadas e complementaram o registro das interacoes observadas na comunidade. Portanto, a informacao associada de ambos os tipos de redes pode ampliar a compreensao das interacoes, aproximando-se, dessa forma, a descricao da rede real. FLORAL VISITATION NETWORK VERSUS POLLEN-TRANSPORT NETWORK BETWEEN BEES AND FLOWERS IN THE ATLANTIC FOREST IN SOUTH BRAZIL . The establishment of plant-pollinator interactions is of great importance for the functioning of ecosystems. These interactions can be recorded directly, by focal observation, or indirectly, by the pollen load on the pollinator body. Thus, the evaluation of the specialization and dependence of mutualistic partners, properties that can be assessed through complex networks, depends on the method used for interaction record. The main objective of this study was to compare a floral-visitation network and a pollen-transport network constructed from interactions between plants and bees sampled in 16 plots in early successional areas in the Atlantic Forest, in Antonina, Parana, southern Brazil. We initially recorded these interactions by focal observation and we sampled the pollen grains on the bees’ body of six bees, and the two networks were restricted to the interactions of these six species. We subdivided the pollen-transport network into a feeding-pollen network, using only the pollen adhered to the bees' corbicules or scopes, and a pollination network, with the pollen present on the bees’ body, except the legs. These networks were compared in relation to the degree ( k ), the specialization index ( d ') and species strength ( F ), through paired t -tests. The pollen-transport network showed a higher number of interactions, higher k , lower d ' and a greater number of plant species than the floral visitation network. There was no variation in F . The feeding- and pollination networks presented similar properties. Pollen analysis revealed that bees tend to perform exclusive foraging flights on pollen flowers. The interactions added from the pollen analysis resulted in differences in the metrics evaluated and complemented the record of the interactions observed in the community. Therefore, the associated information of both types of networks can broaden the understanding of the interactions, thus approaching the actual network description.

Flowering plant species and their nectar-feeding vertebrates exemplify some of the most remarkable biotic interactions in the Neotropics. In the Brazilian Atlantic Forest, several species of birds (especially hummingbirds), bats, and non-flying mammals, as well as one lizard feed on nectar, often act as pollinators and contribute to seed output of flowering plants. We present a dataset containing information on flowering plants visited by nectar-feeding vertebrates and sampled at 166 localities in the Brazilian Atlantic Forest. This dataset provides information on 1902 unique interactions among 515 species of flowering plants and 129 species of potential vertebrate pollinators and the patterns of species diversity across latitudes. All plant-vertebrate interactions compiled were recorded through direct observations of visits, and no inferences of pollinators based on floral syndromes were included. We also provide information on the most common plant traits used to understand the interactions between flowers and nectar-feeding vertebrates: plant growth form, corolla length, rate of nectar production per hour in bagged flowers, nectar concentration, flower color and shape, time of anthesis, presence or absence of perceptible fragrance by human, and flowering phenology as well as the plant's threat status by International Union for Conservation of Nature (IUCN) classification. For the vertebrates, status of threat by IUCN classification, body mass, bill or rostrum size are provided. Information on the frequency of visits and pollen deposition on the vertebrate's body is provided from the original source when available. The highest number of unique interactions is recorded for birds (1771) followed by bats (110). For plants, Bromeliaceae contains the highest number of unique interactions (606), followed by Fabaceae (242) and Gesneriaceae (104). It is evident that there was geographical bias of the studies throughout the southeast of the Brazilian Atlantic Forest and that most effort was directed to flower-hummingbird interactions. However, it reflects a worldwide tendency of more plants interacting with birds compared with other vertebrate species. The lack of similar protocols among studies to collect basic data limits the comparisons among areas and generalizations. Nevertheless, this dataset represents a notable effort to organize and highlight the importance of vertebrate pollinators in this hotspot of biodiversity on Earth and represents the data currently available. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or scientific events.

In the Brazilian Atlantic forest, pollination systems encompass several animal groups and vary from very specialised to highly generalised ones. Plant-pollinator interactions are at the origin and maintenance of diversity and affect ecosystems’ functioning. Moreover, pollination deficit may impact agricultural systems and the dynamics in natural systems with varying importance according to interaction specialisation. We present here examples of pollination studies in the Atlantic forest, highlighting current stressors of plant-pollinator interactions and opportunities to mitigate them. Habitat loss, climate change, and invasive species are the major threats to pollination interactions. Despite the risk, the opportunities for change (restoration, ecological corridors, and protected areas, and landscape management) can contribute to the maintenance of pollination services in the Atlantic forest.

Made available in DSpace on 2019-10-06T16:16:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-02-01 Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. Instituto de Ciências da Natureza Universidade Federal de Alfenas (UNIFAL), Rua Gabriel Monteiro da Silva, 700 Departamento de Botânica Universidade Federal de Juiz de Fora (UFJF), Rua José Lourenço Kelmer, S/n - Martelos Jardim Botânico do Rio de Janeiro, Rua Pacheco Leão, 915 Pontifícia Universidade Católica do Paraná (PUC-PR), Escola de Ciências da Vida, Rua Imaculada Conceição, 1155 Departamento de Ciências Biológicas Universidade Estadual de Santa Cruz (UESC), Campus Soane Nazaré de Andrade, Rodovia Jorge Amado Km 16 Departamento de Botânica Centro Politécnico Universidade Federal do Paraná (UFPR), Caixa Postal 19031, Jardim das Américas Instituto de Florestas Universidade Federal Rural do Rio de Janeiro (UFRRJ), Rodovia BR-465, Km 07 Centro de Ciências Biológicas Departamento de. Botânica Universidade Federal de Santa Catarina (UFSC), Campus Reitor João David Ferreira Lima, s/n - Trindade Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Campus Experimental de Registro, Av. Nelson Brihi Badur, 430 Universidade de Mogi das Cruzes (UMC) Núcleo de Ciências Ambientais, Avenida Doutor Cândido Xavier de Almeida e Souza, 200 Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Praça Infante Dom Henrique, São Vicente Prefeitura Municipal de Olaria, Meio Ambiente, Praça 1° de Março 13, Centro Instituto Federal de Educação Ciência e Tecnologia Baiano (IF-Baiano), Campus Itaberaba, Av. Rio Branco, 1003, Centro Universidade Regional de Blumenau (FURB), Rua Antônio da Veiga, 140 Universidade Federal do Recôncavo da Bahia (UFRB) CCAAB, Rua Rui Barbosa, 710 Instituto de Biociências Cidade Universitária Universidade Federal de Mato Grosso do Sul (UFMS) Departamento Biociências (DBCI) Universidade Federal de Sergipe (UFS), Campus Universitário Prof. Alberto Carvalho,Av. Vereador Olímpio Grande, S/N - Bloco D, Centro Floresce Consultoria Ambiental, Rua Dr. Alexandre Gutierrez, 332 Departamento de Ecologia Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), CP. 199 Ciências Naturais Departamento de Ciências Naturais UESB Universidade Estadual do Sudoeste da Bahia (UESB), Estrada do Bem-Querer km 4, s.n., Bairro Universitário Centro de Ensino Superior em Juiz de Fora (CESJF), Campus Arnaldo Janssen, Luz Interior, 345, Santa Luzia Instituto de Botânica de São Paulo Núcleo de Pesquisas Orquidário do Estado, Avenida Miguel Stefano Faculdade de Engenharia Arquitetura e Urbanismo e Geografia Universidade Federal de Mato Grosso do Sul (UFMS), Caixa Postal 594, 79070-900, Cidade Universitária Departamento de Genética Instituto de Biociências Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500 pr 43312 JB Consultoria Ambiental, Rua Joaquim Firmino, 1318 Departamento de Ciências Florestais Universidade Federal do Paraná (UFPR), Avenida Prefeito Lothário Meissner, 632 Instituto Nacional de Pesquisa da Amazônia (INPA) PPG-Botânica, Av. André Araújo, 2936, Aleixo Empresa Brazileira de Pesquisa Agropecuária (EMBRAPA) Florestas, Estrada da Ribeira, Km 111 Departamento de Ciências Florestais Escola Superior de Agricultura “Luiz de Queiroz” (ESALQ) Universidade de São Paulo (USP), Avenida Pádua Dias 11 Instituto de Ciências Biológicas Universidade de Passo Fundo (UPF), Campus I, Bairro São José, BR 285 Departamento de Botânica Instituto de Biociências Universidade de São Paulo (USP), Rua do Matão, 277 Instituto de Biociências Herbário CGMS Universidade Federal de Mato Grosso do Sul (UFMS), Avenida Costa e Silva s/n Instituto de Ecología Regional (UNT-CONICET), Casilla de Correo, 34, Yerba Buena Centro de Ciências Biológicas e da Saúde - Rodovia Washington Luís Universidade Federal de São Carlos (UFSCAR), Km 335 - SP 310, 13565-905/C.P 676 Departamento de Zoologia Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), CP. 199 Departamento de Botânica Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Avenida 24 A, 1515, CP. 199 Programa de Pós-Graduação em Ciências Ambientais Universidade do Extremo Sul Catarinense (UNESC), Avenida Universitária, 1105, Bairro Universitário Universidade Federal do Vale do São Francisco (UNIFASF) NEMA, Brazil 407, Km 12, lote 543, Projeto de Irrigação Nilo Coelho, s/n Departamento de Biologia Vegetal Instituto de Biologia Universidade Estadual de Campinas (UNICAMP), C. P. 6109 Universidade Federal do Rio de Janeiro (UFRJ), Museu Nacional, Horto Botânico, Quinta da Boa Vista, São Cristóvão Laboratory of Palynostratigraphy and Paleobotany CICyTTP (CONICET-Entre Ríos-UADER), Dr. Matteri y España Diamante Departamento de Ecologia Universidade do Estado do Rio de Janeiro (UERJ), Rua São Francisco Xavier, 524 Ministério do Planejamento Desenvolvimentos e Gestão Esplanada dos Ministérios, Bloco K, Sala 352 Departamento de Biologia Universidade de São Paulo (USP), Campus de Ribeirão Preto, Avenida Bandeirantes, 3900 Universidade Federal de Mato Grosso do Sul (UFMS) Programa de Pós-Graduação em Ecologia e Conservação, Cidade Universitária Departamento de Biodiversidade Evolução e Meio Ambiente Universidade Federal de Ouro Preto (UFOP), Campus, Universitário Morro do Cruzeiro Departamento de Ecologia Instituto de Biociências Universidade Federal do Rio Grande do Norte (UFRN) Departamento de Ciências Biológicas Programa de Pós-Graduação em Ecologia e Conservação da Biodiversidade Universidade Estadual de Santa Cruz (UESC), Rodovia Jorge Amado Km 16 Laboratório de Ciências Ambientais Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Avenida Alberto Lamego 2000, Parque Califórnia, 28013602 Programa de Pós-Graduação em Ecologia de Ecossistemas Universidade Vila Velha (UVV), Rua Comissário José Dantas de Melo, s/n, Boa Vista Laboratório de Ecologia Comportamental e Ornitologia Departamento de Zoologia Centro Politécnico Universidade Federal do Paraná (UFPR), Caixa Postal 19031, Jardim das Américas Centro de Pesquisa Agropecuária de Clima Temperado (Embrapa Clima Temperado), Rodovia BR-392, Km 78, 9° Distrito, Postal Code 403 Instituto de Humanidades Artes e Ciências and Herbário Centro de Pesquisa do Cacau - CEPEC Universidade Federal do Sul da Bahia (UFSB), Campus Jorge Amado, Km 29 Rod. Ilhéus-Itabuna, CP. 07 Departamento de Zootecnia e Ciências Biológicas Universidade Federal de Santa Maria (UFSM), Av. Independência, n° 3751 Instituto Nacional de Colonização e Reforma Agrária - INCRA/SR22 - Alagoas Setor de Meio Ambiente e Recursos Naturais, Rua do Imperador, N° 105 Centro Universidade Federal de Minas Gerais (UFMG), Botânica - Avenida Antônio Carlos, Pampulha Departamento de Ciências Biológicas Laboratório de Ecologia e Restauração Florestal (LERF) Universidade de São Paulo (USP) Escola Superior de Agricultura “Luiz de Queiroz” (ESALQ), Avenida Pádua Dias 11, 13.418-900 Herbarium Royal Botanic Gardens, Kew Centro Universitario Regional del Este Universidad de la República, Tacuarembó y Bvar Departamento de Ciências e Matemática (DCM) Instituto Federal de Educação Ciência e Tecnologia de São Paulo (IFSP), Campus São Paulo, Rua Pedro Vicente, 625, Canindé Centro de Ciências Ciências Biológicas Universidade Federal do Ceará (UFC), Campus do PICI, Bloco 906 Reservas Votorantim, Rua Amauri, 255, 12° andar Facultad de Ciencias Naturales y Museo Universidad Nacional de La Plata, 3, 64st Programa de Pós-Graduação em Ecologia de Biomas Tropicais Universidade Federal de Ouro Preto (UFOP), Campus Morro do Cruzeiro Instituto de Botânica de São Paulo Núcleo de Pesquisas Curadoria do Herbário, Avenida Miguel Stefano Instituto Federal do Rio Grande do Sul (IFRS), Rodovia RS 135, Km 25, Distrito Engenheiro Luiz Englert, Caixa Postal 21 Departamento de Botânica Instituto de Biociências Universidade Federal do Rio Grande do Sul (UFRGS), Avenida Bento Gonçalves, 9500 pr 43433 Conselho Superior de Ensino Pesquisa e Extensão Universidade Paulista (UNIP), Avenida Paulista, 900, 1°. Andar – Herbário, UNIP - Núcleo de Pesquisa em Biodiversidade - Bela Vista, 01310100 Laboratorio de Planificación Territorial Departamento de Ciencias Ambientales Facultad de Recursos Naturales Universidad Católica de Temuco, Rudecindo Ortega, 02950 Departamento de Ecologia e Zoologia – ECZ Universidade Federal de Santa Catarina (UFSC), AC/Cidade Universitária. Trindade. CEP 88.040-970 Universidade Federal de Pernambuco (UFPE), Av. Prof. Moraes Rego, 1235 - Cidade Universitária Instituto de Pesquisa Ambiental da Amazônia (INPA), Rua Horizontina, 104, Centro Woods Hole Research Center, 149, Woods Hole Road Embrapa Cerrados/Centro de Pesquisa Agropecuária dos Cerrados, BR-020, Km 18 Centro Federal de Educação Tecnológica Celso Suckow da Fonseca (CEFET-RJ), Rua Voluntários da Pátria, 30, Bairro Belo Horizonte Universidade do Oeste de Santa Catarina (UNOESC), Campus de São Miguel do Oeste, Rua Oiapoc, 211, Bairro Agostini São Miguel do Oeste Facultad de Ciencias Iguá y Mataojo Universidad de la República Departamento de Biologia Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Via de Acesso Prof. Paulo Donato Castelane, S/N Instituto Federal do Espírito Santo (IFES), Rod. ES-080, Km 93, São João de Petrópolis Universidade Federal de Lavras (UFLA) Programa de Pós-Graduação em Engenharia Florestal, Caixa Postal 3037 Departamento de Microbiologia Imunologia e Parasitologia Universidade Federal de Santa Catarina (UFSC), Campus Universitário, s/n, Sala 05, MIP - Córrego Grande Faculdades Integradas do Vale do Ribeira Laboratório de Biologia Rua Oscar Yoshiaki Magário União das Instituições de Serviços Ensino e Pesquisa Ltda (UNISEP), 185, Jardim das Palmeiras Faculdade de Ciências Biológicas e Ambientais - Rua João Rosa Góes Universidade Federal da Grande Dourados (UFGD), 1761 Reserva Natural Vale, Rodovia Brazil 101 Norte, Interior Divisão de Florestas e Estações Experimentais Instituto Florestal do Estado de São Paulo, Seção de Bauru, Av. Rodrigues Alves, 38-25, Horto Florestal Departamento de Ciências Biológicas Universidade Estadual de Feira de Santana (UEFS), Avenida Transnordestina s.n. División Plantas Vasculares CONICET Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Avenida Ángel Gallardo 470 Universidade Regional Integrada do Alto Uruguai e das Missões (URI), Ciências Biológicas Instituto Tecnológico Vale Biodiversidade e Serviços Ecossistêmicos, Rua Boaventura da Silva, 955 Universidade Federal do Espírito Santo (UFES) Programa de Pós-Graduação em Ciências Florestais, Avenida Governador Lindemberg, 316, Centro Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Campus Experimental de Registro, Av. Nelson Brihi Badur, 430 Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Praça Infante Dom Henrique, São Vicente Departamento de Ecologia Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), CP. 199 Departamento de Zoologia Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), CP. 199 Departamento de Botânica Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Avenida 24 A, 1515, CP. 199 Departamento de Biologia Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Via de Acesso Prof. Paulo Donato Castelane, S/N

Interactions between species are influenced by different ecological mechanisms, such as morphological matching, phenological overlap and species abundances. How these mechanisms explain interaction frequencies across environmental gradients remains poorly understood. Consequently, we also know little about the mechanisms that drive the geographical patterns in network structure, such as complementary specialization and modularity. Here, we use data on morphologies, phenologies and abundances to explain interaction frequencies between hummingbirds and plants at a large geographical scale. For 24 quantitative networks sampled throughout the Americas, we found that the tendency of species to interact with morphologically matching partners contributed to specialized and modular network structures. Morphological matching best explained interaction frequencies in networks found closer to the equator and in areas with low-temperature seasonality. When comparing the three ecological mechanisms within networks, we found that both morphological matching and phenological overlap generally outperformed abundances in the explanation of interaction frequencies. Together, these findings provide insights into the ecological mechanisms that underlie geographical patterns in resource specialization. Notably, our results highlight morphological constraints on interactions as a potential explanation for increasing resource specialization towards lower latitudes.

PREMISE OF THE STUDY Seed and pollen dispersal are key processes shaping plant population dynamics and maintaining genetic diversity. The essence of these processes is the movement of propagules from a parental tree to the site of propagule establishment. The estimation of plant dispersal kernels has remained challenging due to the difficulty of making direct observations. We estimated the dispersal capacity of the endangered palm Euterpe edulis, whose seeds are dispersed by vertebrates and pollen by insects. METHODS We used a hierarchical Bayesian model with genetic data from reproductive plants, juveniles, and embryos to estimate dispersal kernels. Our analyses account for genotyping error and uncertainty in parental assignment. KEY RESULTS We found that seeds were dispersed at most a few hundred meters, but pollen was dispersed up to several kilometers. We hypothesize that this long-distance pollen dispersal is generated mainly by euglossine bees, whereas the main dispersal vectors for short-distance seed dispersal are thrushes. The long-distance dispersal of pollen suggests a high level of gene flow that should maintain genetic diversity of E. edulis. Despite the relation between long-distance dispersal and genetic diversity, we observed low genetic diversity and inbreeding within the local population, which are probably due to restricted gene flow due to the low density of this population and its aggregated spatial distribution. CONCLUSIONS We conclude that if conservation actions are able to restore the population density of E. edulis, the recovery of its genetic diversity will be facilitated because of its high dispersal capacity, especially with regard to pollen.

Changes in the spatial density and availability of resources offered by plants due to habitat fragmentation and overexploitation of the natural environment are likely to affect mutualistic interactions. We tested whether changes in the density of neighborhood conspecific and heterospecific plants and in the availability of resources influence the frequency and composition of floral and frugivorous visitors of eleven individuals of the same population of the threatened palm Euterpe edulis in Brazil. The frequency of floral visitors was positively associated with conspecific density and availability of resources. Species composition was affected by the availability of resources since some bee species were associated with palms that offered more flowers, whereas others were associated with palms that offered less. Two bee species may be able to mediate long-distance pollen-flow for E. edulis: an undetermined species of Euglossini and Apis mellifera. Frugivorous birds were not influenced by any of the factors investigated. Birds of the genus Turdus predominated in the assemblage and were responsible for most of the interactions. This is probably due to the fact that, unlike larger birds, species of Turdus are considered resilient to environmental disturbances. Due to the continuous defaunation and fragmentation of the Atlantic Forest, the number of large birds that can promote long-distance seed dispersal is declining, with implications for the genetic diversity of E. edulis. Measures to restore the population density of E. edulis will likely favor the recovery of its genetic diversity due to its high capacity for distant pollen dispersal. Recovering and protecting large frugivorous birds may also contribute to the maintenance of the population density and genetic diversity of E. edulis.

Plant-pollinator interactions and their reproductive implications are of central importance to the organization of plant populations and communities in restoration areas. We studied the breeding system and flower visitors of Pleroma trichopodum, a pioneer species of the Atlantic Forest. We attempted to answer three questions: (1) Is P. trichopodum dependent on pollinators and mates for reproduction? (2) What are the pollinators of P. trichopodum? (3) Do tree flower-density and flowering-tree density of P. trichopodum enhance the visitation rate of focal trees and their flowers? We tested the breeding system through pollination treatments. We performed focal observations on 10 trees and analyzed the relationship between tree and flower visitation rates, and the tree flower-density and flowering-tree density with Generalized Linear Mixed Models (GLMM). Pleroma trichopodum sets fruits by selfing and outcrossing, both of which occur only through pollinator visits. Bees visited P. trichopodum, and their visitation increased with tree flower-density. Thus, individuals with greater floral displays may function as magnet species, enhancing the pollination of nearby plant species. This characteristic, allied with the ability to reproduce without a mate (selfing) and a tolerance of soggy soils, make P. trichopodum a candidate for Atlantic Forest restoration.

Author(s): Araujo, AC; Martin Gonzalez, AM; Sandel, B; Maruyama, PK; Fischer, E; Vizentin-Bugoni, J; de Araujo, FP; Coelho, AG; Faria, RR; Kohler, G; Las-Casas, FMG; Lopes, AV; Machado, AO; Machado, CG; Machado, IC; McGuire, JA; Moura, AC; Oliveira, GM; Oliveira, PE; Rocca, MA; Rodrigues, LDC; Rodrigues, M; Rui, AM; Sazima, I; Sazima, M; Varassin, IG; Wang, Z; Dalsgaard, B; Svenning, JC | Abstract: Aim: We examined the effects of space, climate, phylogeny and species traits on module composition in a cross-biomes plant–hummingbird network. Location: Brazil, except Amazonian region. Methods: We compiled 31 local binary plant–hummingbird networks, combining them into one cross-biomes metanetwork. We conducted a modularity analysis and tested the relationship between species’ module membership with traits, geographical location, climatic conditions and range sizes, employing random forest models. We fitted reduced models containing groups of related variables (climatic, spatial, phylogenetic, traits) and combinations of groups to partition the variance explained by these sets into unique and shared components. Results: The Brazilian cross-biomes network was composed of 479 plant and 42 hummingbird species, and showed significant modularity. The resulting six modules conformed well to vegetation domains. Only plant traits, not hummingbird traits, differed between modules, notably plants’ growth form, corolla length, flower shape and colour. Some modules included plant species with very restricted distributions, whereas others encompassed more widespread ones. Widespread hummingbirds were the most connected, both within and between modules, whereas widespread plants were the most connected between modules. Among traits, only nectar concentration had a weak effect on among-module connectivity. Main conclusions: Climate and spatial filters were the main determinants of module composition for hummingbirds and plants, potentially related to resource seasonality, especially for hummingbirds. Historical dispersal-linked contingency, or environmental variations not accounted for by the explanatory factors here evaluated, could also contribute to the spatial component. Phylogeny and morphological traits had no unique effects on the assignment of species to modules. Widespread species showed higher within- and/or among-module connectivity, indicating their key role connecting biomes, and, in the case of hummingbirds, communities within biomes. Our results indicate that biogeography and climate not only determine the variation of modularity in local plant–animal networks, as previously shown, but also affect the cross-biomes network structure.

Aim To investigate the association between hummingbird–plant network structure and species richness, phylogenetic signal on species' interaction pattern, insularity and historical and current climate. Location Fifty-four communities along a c. 10,000 km latitudinal gradient across the Americas (39° N–32° S), ranging from sea level to c. 3700 m a.s.l., located on the mainland and on islands and covering a wide range of climate regimes. Methods We measured the level of specialization and modularity in mutualistic plant–hummingbird interaction networks. Using an ordinary least squares multimodel approach, we examined the influence of species richness, phylogenetic signal, insularity and current and historical climate conditions on network structure (null-model-corrected specialization and modularity). Results Phylogenetically related species, especially plants, showed a tendency to interact with a similar array of mutualistic partners. The spatial variation in network structure exhibited a constant association with species phylogeny (R2 = 0.18–0.19); however, network structure showed the strongest association with species richness and environmental factors (R2 = 0.20–0.44 and R2 = 0.32–0.45, respectively). Specifically, higher levels of specialization and modularity were associated with species-rich communities and communities in which closely related hummingbirds visited distinct sets of flowering species. On the mainland, specialization was also associated with warmer temperatures and greater historical temperature stability. Main conclusions Our results confirm the results of previous macroecological studies of interaction networks which have highlighted the importance of species richness and the environment in determining network structure. Additionally, for the first time, we report an association between network structure and species phylogenetic signal at a macroecological scale, indicating that high specialization and modularity are associated with high interspecific competition among closely related hummingbirds, subdividing the floral niche. This suggests a tighter co-evolutionary association between hummingbirds and their plants than in previously studied plant–bird mutualistic systems.

The theory of complex networks has been recently used to explain ecological associations between nurses and seedlings in plant facilitation systems. The structure of these networks is potentially affected by morphological, ecological and evolutionary factors that can determine the facilitative interactions. In the present study, we evaluate the role of the projected crown area of the nurse plant, the dispersal syndrome, the abundance and the phylogeny relationships with seedlings as drivers of network structure in facilitation networks. To test these parameters, we used an ecotonal forest–grassland system in southern Brazil that experienced historical forest expansion over the grassland in the last few centuries. In two State Parks, Guartela (GUA) and Vila Velha (VVL), we sampled tree species (nurses and seedlings) along four transects parallel to the forest edge, with five sampling stations along each transect. Tree seedlings (height >0.3 m) were sampled below the nurse's crown (i.e. isolated woody plants, height >1.5 m) and over the grassland area. A total of 160 nurses and 358 seedlings were sampled. Seedling abundance and richness were greater below a nurse's crown than on open grassland. Nurse abundance was the best predictor of the observed interaction matrix. Probabilistic matrices based on abundance, abundance and phylogeny, and dominance were able to predict the observed nestedness values, and they were also closest to the observed connectance, although all of the probabilistic matrices have underestimated this property. Specialization was predicted by abundance and phylogeny, abundance and projected crown area drivers for VVL, and the abundance based models were closest to the predicted specialization for GUA. The result of a similar pattern in predictability between sites indicates that the influences of morphology and evolutionary and ecological processes over the facilitation interactions are equivalent on a regional scale. Woody plant abundance was a key factor for the facilitation networks, driving forest expansion along the subtropical forest–grassland ecotone.

Climate change is significantly influencing phenology. One potential effect is that historically interacting partners will respond to climate change at different rates, creating the potential for a phenological mismatch among previously synchronized interacting species, or even sexes of the same species. Focusing on plant demographics in a plant–pollinator interaction, we develop a hybrid dynamical model that uses a “non-autonomous” differential equation system (Zonneveld model) for within-season dynamics and discrete equations for season-to-season dynamics. Our model outlines how and when changes in the relative phenologies of an interacting species pair will alter the demographic outcome of the interaction. For our plant–pollinator system, we find that plant population growth rates are particularly sensitive to phenology mismatch when flowers are short-lived, when pollinators are short-lived, or when flowers and pollinators exhibit high levels of within-population synchrony in emergence or arrival dates. More generally, our aim is to introduce the use of hybrid dynamical models as a framework through which researchers can directly explore the demographic consequences of climatically driven phenological change.

Unfortunately, the detailed description of the ESM material went wrong in the published version of the dataset.

Plant size and clonality are important traits for explaining the reproductive effort of clonal plants. Larger plants can invest more resources into reproduction, and clonality is known to increase reproductive effort. Moreover, reproductive effort is influenced by environmental variation, and so the spatial distribution of plants may affect plant reproductive effort. We investigated the effect of plant size, clonality and spatial distribution on the reproductive effort of Vriesea carinata in the Atlantic Forest in the state of Paraná, Brazil. We marked twenty individual plants and measured their rosette size, biomass and number, as well as rosette reproductive effort (number of flowers, fruits and seeds). We also evaluated the relationship between reproductive effort and spatial distribution of plants. Reproductive effort did not correlate with size, whereas greater clonal growth contributed to a lower reproductive effort because rosettes within clones that had more rosettes set fewer flowers. We found that plants growing closer to each other exhibited similar reproductive efforts independently of vegetative traits, because reproductive traits were spatially autocorrelated. In Vriesea carinata, the main drivers of reproductive effort are clonality, which decreases flower production, and spatial factors, which result in greater similarity in reproductive efforts among more proximate plants.

Ecological communities that experience stable climate conditions have been speculated to preserve more specialized interspecific associations and have higher proportions of smaller ranged species (SRS). Thus, areas with disproportionally large numbers of SRS are expected to coincide geographically with a high degree of community-level ecological specialization, but this suggestion remains poorly supported with empirical evidence. Here, we analysed data for hummingbird resource specialization, range size, contemporary climate, and Late Quaternary climate stability for 46 hummingbird–plant mutualistic networks distributed across the Americas, representing 130 hummingbird species ( ca 40% of all hummingbird species). We demonstrate a positive relationship between the proportion of SRS of hummingbirds and community-level specialization, i.e. the division of the floral niche among coexisting hummingbird species. This relationship remained strong even when accounting for climate, furthermore, the effect of SRS on specialization was far stronger than the effect of specialization on SRS, suggesting that climate largely influences specialization through species' range-size dynamics. Irrespective of the exact mechanism involved, our results indicate that communities consisting of higher proportions of SRS may be vulnerable to disturbance not only because of their small geographical ranges, but also because of their high degree of specialization.

Aim: To investigate the role of alien plants in mutualistic plant-hummingbird networks, assessing the importance of species traits, floral abundance and insularity on alien plant integration. Location: Mainland and insular Americas. Methods: We used species-level network indices to assess the role of alien plants in 21 quantitative plant-hummingbird networks where alien plants occur. We then evaluated whether plant traits, including previous adaptations to bird pollination, and insularity predict these network roles. Additionally, for a subset of networks for which floral abundance data were available, we tested whether this relates to network roles. Finally, we tested the association between hummingbird traits and the probability of interaction with alien plants across the networks. Results: Within the 21 networks, we identified 32 alien plant species and 352 native plant species. On average, alien plant species attracted more hummingbird species (i.e. aliens had a higher degree) and had a higher proportion of interactions across their hummingbird visitors than native plants (i.e. aliens had a higher species strength). At the same time, an average alien plant was visited more exclusively by certain hummingbird species (i.e. had a higher level of complementary specialization). Large alien plants and those occurring on islands had more evenly distributed interactions, thereby acting as connectors. Other evaluated plant traits and floral abundance were unimportant predictors of network roles. Short-billed hummingbirds had higher probability of including alien plants in their interactions than long-billed species. Main conclusions: Once incorporated into plant-hummingbird networks, alien plants appear strongly integrated and, thus, may have a large influence on network dynamics. Plant traits and floral abundance were generally poor predictors of how well alien species are integrated. Short-billed hummingbirds, often characterized as functionally generalized pollinators, facilitate the integration of alien plants. Our results show that plant-hummingbird networks are open for invasion. © 2016 John Wiley & Sons Ltd.

Ocotea porosa has been extensively exploited over the past few decades because of the quality of its wood. Today, populations are reduced and the species is now included in the Red List of threatened species by the International Union for Nature Conservation. For conservation and management purposes, it is extremely important that we understand its reproductive ecology. Floral morphology was described based on field and scanning electron microscopic examination. The reproductive system was determined through experimentally controlled pollination along with observations of pollen tube growth. Pollinators were identified through field observations. Flowers of O. porosa are small, shallow, inconspicuous, asynchronous and grouped in inflorescences. This species presented self-compatibility, but did not reproduce through apomixy and spontaneous self-pollination was very rare (5%). Despite being monoclinal, flowers were protogynic, and the gynoecium was receptive after the first day of anthesis when the anthers were closed. Spontaneous self-pollination was avoided by the extrorse position of the anthers of the internal stamens. Frankliniella gardeniae (Thysanoptera) was the only pollinating species observed and, after visiting several asynchronous flowers in the same inflorescence, favors geitonogamy. Together the small distance supposedly achieved by thrips in flight and the small population density of O. porosa can reduce the chances of cross-pollination in this species. If so, conservation measures must include preservation of the current population and possibly planting to increase population density. This would reduce the distance between individuals and increase genetic variability. Thrips as pollinators must be included in conservation planning for O. porosa.

Th e concept of pollination syndromes has been widely questioned, since plant – pollinator interactions have proved to be more generalist than was previously thought. We examined whether the network of a tropical high-altitude grassland contained groups of plants and pollinators that interact preferentially with each other. A general binary matrix was created. To assess the robustness of myophily, in all analyses we considered: 1) the whole network, 2) the network after the wasps were removed, and 3) the network after the fl ies were removed. For each network we evaluated whether: 1) the observed interactions were more related to syndromes than expected by chance, compared to an expected matrix; 2) there was a modular structure; 3) the modules found were more related to syndromes than expected by chance, compared to another expected matrix; 4) the syndromes were equally robust. For this analysis, the general matrix was subdivided into smaller matrices that included each pollination syndrome separately. To test the infl uence of the functional groups of pollinators and the phylogeny of plants, in addition to the general matrix, we also considered the fi rst expected matrix, a quantitative functional group and a plant phylogeny matrix. Th e pollination syndromes determined the pattern of interactions in the network: 69% of the total interactions resulted from the functional group of pollinators predicted by the plant syndrome. Th e network showed greater modularity (13 modules) than expected by chance, mostly consisting of the expected functional groups of pollinators and plant syndromes. Th e modules were associated with pollination syndromes more than was predicted by chance. Most of the variation in interactions was explained by functional groups of pollinators or by plant syndromes. Plant phylogeny did not account for a signifi cant amount of variation in the interactions. Our fi ndings support the concept of pollination syndromes. However, the interactions were not equally predicted by diff erent pollination syndromes, and the accuracy of the prediction was strongest for ornithophily and melittophily.

Floral color changes are common among Melastomataceae and have been interpreted as a warning mechanism for bees to avoid old flowers, albeit increasing long-distance flower display. Here the reproductive systems of Tibouchina pulchra and T. sellowiana were investigated by controlled pollinations. Their pollinators were identified, and experiments on floral color and fragrance changes were conduced to verify if those changes affect the floral visitation. Both Tibouchina species are self compatible. The flowers lasted three days or more, and the floral color changed from white in the 1st day to pink in the following days. Pollen deposition on stigma induced floral color change. The effectiveness of the pollination is dependent on bees’ size; only large bees were regarded as effective pollinators. In experimental tests, the bees in T. pulchra preferred the natural white flowers while the visitors of T. sellowiana were attracted by both natural and mimetic 1st-day flowers (2nd-day flowers with experimentally attached 1st-day flower petals). During the experiments on floral fragrance, the bees visited both natural and mimetic 1st-day flowers (2nd-day flowers with 1st-day flower scents). In both experiments, the bees avoided natural 2nd-day flowers, but seldom visited modified 2nd-day flowers. The attractiveness of T. pulchra and T. sellowiana flowers cannot be attributed exclusively to the color or the fragrance separately, both factors seemingly act together.

Anisophylly can be defined as the unequal growth of two leaves in a pair from a single branch node. It occurs in several opposite-leafed taxa, even in those with apparently no phylogenetic proximity. We have intended here to classify and describe the anisophylly found in ten species of Melastomataceae from two genera, Leandra and Miconia, using morphometric data. We developed a method to quantify the level of anisophylly in these species, using a parameter called “Anisophylly Index” (AI), with values ranging from nearly 0 (isophyllous) to 1 (strongly anisophyllous). A comparison between the leaves from the erect and lateral branches of Leandra barbinervis showed that this species has incomplete lateral anisophylly; i.e., only the lateral branches are anisophyllous, and in these only the pairs positioned in a dorso-ventral position are unequal, while pairs positioned in a horizontal position are isophyllous. The lateral branches of all species showed incomplete anisophylly. There is no apparent re...

The reciprocal importance of bromeliads and hummingbirds has been proposed for many years, even suggesting coevolution between these two groups. Nevertheless, data are lacking that allow a better test of the relationships involved. Here we investigate the relationship between bromeliads and hummingbirds in an area of secondary Atlantic rain forest in southern Brazil. The study examined the interactions among 12 species of bromeliad and 10 of hummingbird at Reserva Natural Salto Morato, Paraná state. The number of flowering species of bromeliad and the species richness and abundance of hummingbirds were quantified monthly between November 2004 and October 2005. Focal observations on each bromeliad species were made to determine the hummingbird visitors. Neither species richness nor abundance of hummingbirds were related to bromeliad phenology. Together with the monthly variation in visit frequency by a given pollinator to a given plant, these factors indicate a generalization in the use of bromeliads by hummingbirds and argue against tight coevolution. Ramphodon naevius and Thalurania glaucopis were the main pollinators in the community. Aechmea nudicaulis was the most generalist bromeliad species. The generalist species interacted with other generalists or with asymmetric specialists and there was no specialist–specialist interaction. This produced a strongly organized and nested matrix of interactions. This nestedness is similar to other plant-pollinators networks, supporting the hypothesis that the evolutionary relationship between bromeliads and hummingbirds is no stronger than that of other pollination networks.

The abundance and distribution of resources for pollinators modulate the reproduction of plants. This study attempted to determine whether and how the fruiting success of Tibouchina trichopoda flowers varies due to plant size, number of flowers produced, distance between individuals and cardinal orientation of the flowers. From July 2009 to February 2010, we conducted monthly evaluations of 21 plants in an area of regenerating forest within the Atlantic Forest biome, located near the municipality of Antonina, in southern Brazil. Floral density was monitored weekly. During the study period, the species bloomed twice: once during the cool, dry season, showing an extended flowering period with scattered flowering individuals; and once during the hot, rainy season, showing a brief flowering period with a high density of flowering individuals. Plant size was not found to influence fruiting success. There was greater production of flowers and fruits during the brief flowering period. The extent of the floral display positively affected the fruiting success of the flowers, the effect being greater when the density of flowers was low and tending to stabilize at higher densities. The northern-facing portions of tree crowns produced more flowers and therefore had greater fruiting success than did the southern-facing portions. However, the proportion of fruits produced per flower was the same.

Pollinator guild organization and its consequences for reproduction in three synchronopatric species of Tibouchina (Melastomataceae). In co-flowering plant species, pollinator sharing can result in interspecific pollen transfer and fecundity reduction. Competition will be relaxed whenever there is a large amount of initial pollen supply or if each plant species occupies different habitat patches. Reproduction in Tibouchina cerastifolia (Naudin) Cogn., T. clinopodifolia (DC.) Cogn. and T. gracilis (Bonpl.) Cogn. was studied in an area of Atlantic rainforest to examine whether synchronopatry induces time partitioning among pollinator species. Eleven bee species comprised the pollinator guild. Among pollinators, there were overlaps in bee species composition and in flower visitation time. Direct competition for pollen in Tibouchina Aubl. at the study site seems to lead to different activity periods among the bee species, in which Bombus pauloensis Friese,1913 was most active earlier, while the other species were active later in the day. Bombus pauloensis, the largest bee species recorded on Tibouchina flowers, was the most important and efficient pollinator. This species harvested pollen before the other species and had the shortest handling time. The plants reproduced sexually by selfing or outcrossing, and hybridization was not avoided by incompatibility reactions at the style. The avoidance of direct competition for pollen and no pollinator partitioning among the synchronopatric species of Tibouchina may reflect a facilitative interaction among these pioneer plants.Organização da guilda de polinizadores e sua consequência para reprodução em três espécies sincropátricas de Tibouchina (Melastomataceae). Em espécies de plantas que co-florescem, a partilha de polinizadores pode resultar em transferência interespecífica de pólen e redução da fecundidade. A competição pode ser relaxada quando existe uma grande quantidade de suprimento de pólen ou se cada planta ocupa manchas distintas do hábitat. A reprodução de Tibouchina cerastifolia (Naudin) Cogn., T. clinopodifolia (DC.) Cogn. e T. gracilis (Bonpl.) Cogn. foi estudada em Floresta Atlântica para verificar se a sincronopatria levava à partilha temporal das espécies de polinizadores. Onze espécies de abelhas compuseram a guilda de polinizadores. Entre eles, houve sobreposição na composição de espécies de polinizadores e no período de visitação floral. A competição direta por pólen em Tibouchina Aubl. na área de estudo parece levar a distintos períodos de atividade entre as abelhas, onde Bombus pauloensis Friese,1913 foi mais ativa mais cedo enquanto que as outras espécies foram ativas mais tarde. Bombus pauloensis, a maior espécie de abelha registrada em nas flores de Tibouchina, foi o polinizador mais importante e eficiente. Esta espécie coletava pólen antes das outras abelhas e apresentou um menor tempo de manipulação das anteras. As plantas se reproduziram sexuadamente, por autogamia e xenogamia e a hibridação não foi inibida por reações de incompatibilidade no estilete. A ausência de competição direta por pólen e de partilha de polinizadores pode refletir uma interação de facilitação entre estas três espécies pioneiras e sincronopátricas de Tibouchina.

Niche and neutral processes shape community assembly with a possible shift of niche and neutral importance in communities undergoing temporal changes during succession. Functional diversity helps to discriminate assembly processes since trait distribution is dependent on those processes. We evaluated the changes in reproductive traits related to pollination and seed dispersal in a successional gradient in an Atlantic Forest area, Southern Brazil. We surveyed forests undergoing regeneration varying in age from 2 to 80 years after pasture abandonment. We expected an increase in functional diversity of reproductive traits and a greater role of limiting similarity across succession. Abiotic and mixed pollination systems, dioecious sexual system, biotic dispersed, many-seeded and small-seeded species decreased as the forest got older. Conversely, bee-pollinated, bell-shaped, small and androgynous flowers increased across forest succession as well biotic dispersed and large-seeded species. Functional richness and functional dispersion were higher in older forests. Changes in functional diversity were positively related to species richness, indicating that species enrichment in older forests added new sets of reproductive traits. These changes in trait distribution and functional diversity across succession in the Atlantic Forest suggest an increased role of biotic interactions and limiting similarity process structuring plant assemblages of second-growth tropical forests. Resumo As florestas apresentam um enriquecimento gradual de espécies e um aumento em complexidade estrutural e funcional durante a sucessão. Este trabalho caracterizou os traços reprodutivos de plantas relacionados à polinização e à dispersão em um gradiente sucessional, em uma área de Mata Atlântica, Sul do Brasil. O levantamento das espécies foi realizado em áreas florestais sucessionais oriundas de regeneração natural, em idades variando entre 2 e 80 anos após o abandono da pastagem. Houve predominância de flores polinizadas por abelhas, abertas, hermafroditas e que disponibilizam o pólen como em todos estádios sucessionais. Os sistemas de polinização abiótico e misto, sistema sexual dióico, espécies com dispersão abiótica, com muitas sementes e sementes pequenas diminuíram com a idade das florestas. Espécies polinizadas por abelhas, flores com corola funil/sino, como de corola pequena e andróginas assim como espécies dispersas bioticamente e com sementes grandes aumentaram no gradiente sucessional. A riqueza funcional e a dispersão funcional aumentaram no gradiente sucessional. As mudanças da diversidade funcional foram relacionadas com o aumento da riqueza de espécies indicando que o enriquecimento de espécies em florestas mais velhas adicionou novos conjuntos de traços reprodutivos. Estas mudanças de distribuição de traços e de diversidade funcional no gradiente sucessional sugerem um incremento do papel de interações bióticas na estruturação de assembleias de plantas de florestas tropicais secundárias.