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Approximately 20,000 species of flowering plant offer mainly pollen to their pollinators, generally bees. Stamen dimorphism, a floral trait commonly present in some pollen flowers, is thought to be associated with exclusive pollen provision for highly effective bee pollinators. Notwithstanding, little is known about how stamen dimorphism is related to other floral morphological traits and, consequently, plant-pollinator interactions at the community scale. Here we investigated the relationship between stamen dimorphism and other floral morphological traits, as well as the interactions with pollinators in plants of Melastomataceae. We characterized each plant species as stamen dimorphic or stamen isomorphic according to differences in size and shape between stamen sets. Data on interactions between the plants and their bee pollinators were analysed as quantitative bipartite networks. We found that petal and style size and shape were correlated to stamen dimorphism. Stamen dimorphic species present larger flowers and less variable style shapes than stamen isomorphic species. Furthermore, stamen dimorphism is associated with higher richness of visiting bees, i.e. higher ecological generalization. During the evolutionary history of Melastomataceae, the dependence on pollinators for fruit set has possibly favoured the evolution of larger flowers with dimorphic stamens, which in turn are able to make use of a larger spectrum of pollen-collecting bees, leading to ecological generalization.

Besides the primary diet of nectar, pollen, and fruits, the flower-visiting Musk Lorikeet Glossopsitta concinna feeds on lerps. However, a description of its behaviour while foraging on this latter source seems to be lacking. We describe and illustrate the feeding behaviour of the Musk Lorikeet on Spondylaspidinae psylloid lerps. The lerps were within young deformed eucalypt leaves, and the Lorikeet had to open a deformed leaf and remove the starchy lerps to feed on them. The Lorikeet took c. 1 minute to process each leaf, which suggests that these lerps are an important or satisfying food.

Functional traits can determine pairwise species interactions, such as those between plants and pollinators. However, the effects of biogeography and evolutionary history on trait-matching and trait-mediated resource specialization remain poorly understood.We compiled a database of 93 mutualistic hummingbird-plant networks (including 181 hummingbird and 1,256 plant species), complemented by morphological measures of hummingbird bill and floral corolla length. We divided the hummingbirds into their principal clades and used knowledge on hummingbird biogeography to divide the networks into four biogeographical regions: Lowland South America, Andes, North & Central America, and the Caribbean islands. We then tested: (a) whether hummingbird clades and biogeographical regions differ in hummingbird bill length, corolla length of visited flowers and resource specialization, and (b) whether hummingbirds' bill length correlates with the corolla length of their food plants and with their level of resource specialization.Hummingbird clades dominated by long-billed species generally visited longer flowers and were the most exclusive in their resource use. Bill and corolla length and the degree of resource specialization were similar across mainland regions, but the Caribbean islands had shorter flowers and hummingbirds with more generalized interaction niches. Bill and corolla length correlated in all regions and most clades, that is, trait-matching was a recurrent phenomenon in hummingbird-plant associations. In contrast, bill length did not generally mediate resource specialization, as bill length was only weakly correlated with resource specialization within one hummingbird clade (Brilliants) and in the regions of Lowland South America and the Andes in which plants and hummingbirds have a long co-evolutionary history. Supplementary analyses including bill curvature confirmed that bill morphology (length and curvature) does not in general predict resource specialization.These results demonstrate how biogeographical and evolutionary histories can modulate the effects of functional traits on species interactions, and that traits better predict functional groups of interaction partners (i.e. trait-matching) than resource specialization. These findings reveal that functional traits have great potential, but also key limitations, as a tool for developing more mechanistic approaches in community ecology.A free Plain Language Summary can be found within the Supporting Information of this article.

Floral resources can be recognized by visitors through attractants that signal their presence. However, besides petals, it is still unclear how floral elements in heterantherous species are perceived by visiting bees. In this study, we aim to understand the role of stamens and petals of Pleroma granulosum and P. raddianum in attracting pollination bees, mainly by evaluating whether pollinator behaviour differs in response to different sized stamens between which there is no apparent colour contrast. Using colour visual models, we estimated bee colour discrimination between stamen sets and corolla in both species and carried out preference experiments among floral elements, using the bees Bombus morio and Xylocopa frontalis as models in the field. Pollination and feeding stamens are not discriminable by bees in both plant species. Bees only preferred flowers with petals, indicating that they are essential to long-distance attraction. During preferential tests, bees seemed to better respond to visual stimuli on the right side, suggesting lateralization. We also demonstrate that tactile stimulation by the anthers is necessary to trigger bee buzzing behaviour. Thus, since bees were not specifically attracted to any stamen set, heteranthery without colour differences between stamens is not enough to determine bee choice behaviour.

Intraspecific floral colour polymorphism is a common trait of food deceptive orchids, which lure pollinators with variable, attractive signals, without providing food resources. The variable signals are thought to hinder avoidance learning of deceptive flowers by pollinators. Here, we analysed the cognitive mechanisms underlying the choice of free-flying stingless bees Scaptotrigona aff. depilis trained to visit a patch of artificial flowers that displayed the colours of Ionopsis utricularioides, a food deceptive orchid. Bees were trained in the presence of a non-rewarding colour and later tested with that colour vs. alternative colours. We simulated a discrete-polymorphism scenario with two distinct non-rewarding test colours, and a continuous-polymorphism scenario with three non-rewarding test colours aligned along a chromatic continuum. Bees learned to avoid the non-rewarding colour experienced during training. They thus preferred the novel non-rewarding colour in the discrete-polymorphic situation, and generalized their avoidance to the adjacent colour of the continuum in the continuous-polymorphism situation, favouring thereby the most distant colour. Bees also visited less flowers and abandoned faster a non-rewarding monomorphic patch than a non-rewarding polymorphic patch. Our cognitive analyses thus reveal that variable deceptive orchids disrupt avoidance learning by pollinators and exploit their generalization abilities, which make them favour distinct morphs.

The glossophagine Pallas’s long-tongued bat (Glossophaga soricina) fares well in urban environments across its range. In addition to roost sites, there are nectar and fruit sources available in diverse situations across the urban gradient. Phyllostomid bats that thrive in urbanized situations are behaviorally plastic generalists and rely on patches of ornamental or feral plants as food sources. Herein we report on G. soricina and its food sources at an urbanized site in Southeastern Brazil. This small phyllostomid bat consumes nectar from landscaping ornamental plants, besides consuming the soft pulp along with the tiny seeds of pioneer trees and shrubs. In addition to these natural sources, the bat exploits hummingbird feeders to consume the sugared water. Ingested small seeds are defecated in flight, the bat acting as a disperser of pioneer plants that favor cleared areas. Glossophaga soricina role as flower-pollinator and seed-disperser at Neotropical urban areas merits further attention due both to the maintenance of urban biodiversity and delivery of ecosystem services. Resumo: O morcego beija-flor (Glossophaga soricina) adapta-se a ambientes urbanos na sua área de distribuição. Além de abrigos diurnos, há fontes de néctar e frutos ao longo do gradiente urbano. Morcegos filostomídeos que se adaptam a situações urbanas são generalistas comportamentalmente flexíveis e dependem de trechos com plantas ornamentais ou ferais como fonte alimentar. Relatamos aqui informações sobre o morcego beija-flor e suas fontes alimentares em um local urbanizado no sudeste do Brasil. Este pequeno morcego glossofagíneo busca néctar em plantas usadas em paisagismo, além de consumir a polpa macia, juntamente com as sementes minúsculas, de plantas pioneiras. Além destas fontes naturais, o morcego explora água açucarada dos bebedouros de beija-flores. Sementes pequenas são defecadas em voo e o morcego age como dispersor de plantas poineiras em áreas sem vegetação. A função de G. soricina como polinizador de flores e dispersor de sementes em áreas urbanas nos Neotrópicos merece atenção adicional devido à manutenção da biodiversidade urbana e da prestação de serviços ecossistêmicos.

Interactions between plant and pollinators are associated with the origin and maintenance of species diversity, as well as ecosystem functioning. The potential of pollination as an ecosystem service is evidenced by its association with food production. Understanding pollination at the landscape scale is essential for characterizing the pollination service for several crops that depend on pollinators for fruit and seed set that make up the human diet. Our aim was to carry out a literature review of studies and projects funded by BIOTA/FAPESP to illustrate the main research approaches developed in the field of Pollination Biology, especially related to plant-pollinator interactions. Plant-pollinator interactions in the Atlantic forest were leveraged as a result of this long-term research program, during which several papers were published in international journals. Pollination by bees (melittophily) was the most representative pollination system studied. In addition to melittophily, other interactions were studied such as pollination by hawkmoths (sphingophily), by hummingbirds (ornithophily) and by bats (chiropterophily). The specific mutualistic relationships between fig trees and fig wasps were also subject of studies within the Program. At the beginning of the BIOTA/FAPESP Program, there were many gaps in basic information about pollination and breeding systems of Brazilian native plant species. Thus, the Program was fundamental to fuel research on the natural history of plants and pollinators from the Atlantic forest. Overall, the Program funded studies that investigated themes such as functional pollination ecology, pollinator effectiveness, plant population genetics, structure and dynamics of plant-pollinator interaction networks, as well as geographic distribution and macroevolution of pollination systems, as well as genetic and molecular studies of native plant populations focusing on pollen flow and genetic structure of populations. Additionally, studies on pollination in the context of landscape ecology had the aim of assessing the effects of forest fragmentation on the functioning of plant populations and their interactions with pollinators and the relationships between landscape structure and ecological processes, biodiversity, and ecosystem service. Therefore, the Program had a prominent role in producing basic data with great implications for understanding the ecology and promoting the conservation of plant-pollinator interactions. Resumo A interação planta-polinizador está associada à origem e manutenção da diversidade de espécies de plantas e ao funcionamento dos ecossistemas. O potencial da polinização como serviço ecossistêmico é destacado quando associado à produção de alimentos. Compreender esta interação na escala da paisagem é essencial para caracterizar o serviço de polinização para muitos cultivos que dependem dos polinizadores para a formação de frutos e sementes que integram a dieta humana. O objetivo deste trabalho foi realizar uma revisão bibliográfica de estudos e projetos financiados pelo BIOTA/FAPESP para ilustrar as principais abordagens de pesquisa desenvolvidas no campo da Biologia da Polinização, especialmente relacionadas à interação planta-polinizador. As interações planta-polinizador na Mata Atlântica foram alavancadas como resultado desse programa de pesquisa de longo prazo, durante o qual vários artigos foram publicados em revistas internacionais. A polinização por abelhas (melitofilia) foi o sistema de polinização mais representativo estudado. Além da melitofilia, outras interações foram estudadas, como a polinização por mariposas (esfingofilia), por beija-flores (ornitofilia) e por morcegos (quiropterofilia). As relações mutualísticas específicas entre figueiras e vespas do figo também foram objeto de estudos no âmbito do Programa. No início do Programa BIOTA/FAPESP, havia muitas lacunas sobre informações básicas sobre polinização e sistemas de reprodução de espécies vegetais nativas brasileiras. Assim, o Programa foi fundamental para desenvolver pesquisas sobre a história natural de plantas e polinizadores da Mata Atlântica. No geral, o Programa financiou estudos que investigaram temas como ecologia funcional da polinização, eficácia de polinizadores, genética de populações de plantas, estrutura e dinâmica de redes de interação planta-polinizador, bem como distribuição geográfica e macroevolução dos sistemas de polinização, além de estudos genéticos e moleculares de populações de plantas nativas com foco no fluxo de pólen. Adicionalmente, estudos sobre polinização no contexto da ecologia da paisagem tiveram como objetivo avaliar os efeitos da fragmentação florestal no funcionamento das populações de plantas e suas interações com os polinizadores e as relações entre a estrutura da paisagem e os processos ecológicos, biodiversidade e serviços ecossistêmicos. Portanto, o Programa teve um papel de destaque na produção de dados básicos com grandes implicações para o entendimento da ecologia e promoção da conservação das interações planta-polinizador.

Nectar is an important floral resource in the establishment of plant-pollinator interactions. Recent studies have shown that nectariferous tissues are independent of the ABC model of floral development and that ecological interactions can modify their expression. In this sense, it would be interesting to study generalist species in relation to nectar production and nectary morpho-anatomy to verify the strategies used to attract different pollinator groups. We recorded nectar production dynamics in Aechmea vanhoutteana (Bromeliaceae) from a morpho-functional and ultrastructural perspective. We observed different species of hummingbirds, bees and butterflies visiting flowers of A.vanhoutteana, and their frequency varied throughout floral anthesis. The nectar volume and quantity of sugar also varied significantly during anthesis, and this spatial and temporal variability seems to be related to an increase in bee visits, representing an important aspect of the reproductive strategy of this species, since bees can fly longer distances than the observed hummingbirds (although both have territorial behaviours). Thus, it can be suggested that anatomical and physiological nectar traits may be related to pollen flow, an important aspect of the reproductive strategy of A. vanhoutteana, suggesting plant resource allocation for optimizing reproduction through nectar production.

Research on resource partitioning in plant-pollinator mutualistic systems is mainly concentrated at the levels of species and communities, whereas differences between males and females are typically ignored. Nevertheless, pollinators often show large sexual differences in behaviour and morphology, which may lead to sex-specific patterns of resource use with the potential to differentially affect plant reproduction and diversification. We investigated variation in behavioural and morphological traits between sexes of hummingbird species as potential mechanisms underlying sex-specific flower resource use in ecological communities. To do so, we compiled a dataset of plant-hummingbird interactions based on pollen loads for 31 hummingbird species from 13 localities across the Americas, complemented by data on territorial behaviour (territorial or non-territorial) and morphological traits (bill length, bill curvature, wing length and body mass). We assessed the extent of intersexual differences in niche breadth and niche overlap in floral resource use across hummingbird species. Then, we tested whether floral niche breadth and overlap between sexes are associated with sexual dimorphism in behavioural or morphological traits of hummingbird species while accounting for evolutionary relatedness among the species. We found striking differences in patterns of floral resource use between sex. Females had a broader floral niche breadth and were more dissimilar in the plant species visited with respect to males of the same species, resulting in a high level of resource partitioning between sexes. We found that both territoriality and morphological traits were related to sex-specific resource use by hummingbird species. Notably, niche overlap between sexes was greater for territorial than non-territorial species, and moreover, niche overlap was negatively associated with sexual dimorphism in bill curvature across hummingbird species. These results reveal the importance of behavioural and morphological traits of hummingbird species in sex-specific resource use and that resource partitioning by sex is likely to be an important mechanism to reduce intersexual competition in hummingbirds. These findings highlight the need for better understanding the putative role of intersexual variation in shaping patterns of interactions and plant reproduction in ecological communities.La investigación sobre la partición de recursos en los sistemas mutualistas planta-polinizador se concentra principalmente en los niveles de especies y comunidades, mientras que las diferencias entre machos y hembras suelen ser ignoradas. Sin embargo, los polinizadores suelen mostrar grandes diferencias sexuales en su comportamiento y morfología, lo que puede dar lugar a patrones específicos de uso de recursos para cada sexo con el potencial de afectar de forma diferencial la reproducción y la diversificación de las plantas. Se estudió la variación en los rasgos de comportamiento y morfológicos entre sexos de las especies de colibríes como posibles mecanismos que explican el uso de recursos florales específicos para cada sexo en las comunidades ecológicas. Para ello, se recopiló un conjunto de datos de interacciones planta-colibrí con base en las cargas de polen de 31 especies de colibríes de 13 localidades en las Américas, además de datos sobre su comportamiento territorial (territorial o no territorial) y rasgos morfológicos (longitud y curvatura del pico, longitud del ala y masa corporal). Se evaluaron las diferencias intersexuales en la amplitud y el solapamiento del nicho en el uso de los recursos florales para las distintas especies de colibríes. Posteriormente, se comprobó si la amplitud del nicho floral y el solapamiento entre sexos están asociados con el dimorfismo sexual en los rasgos de comportamiento o morfológicos de las especies de colibríes, teniendo en cuenta el parentesco evolutivo entre las especies. Se encontraron diferencias notables en los patrones de uso de los recursos florales entre sexos. Las hembras presentaron una mayor amplitud de nicho floral y fueron más disímiles en las especies de plantas visitadas con respecto a los machos de la misma especie, lo que resultó en un alto nivel de partición de recursos entre los sexos. Se encontró que tanto la territorialidad como los rasgos morfológicos están relacionados con el uso de recursos específicos por sexo en las especies de colibríes. En particular, el solapamiento de nicho entre sexos fue mayor para las especies territoriales que para las no territoriales y, además, el solapamiento de nicho se asoció negativamente con el dimorfismo sexual en la curvatura del pico en las especies de colibríes. Estos resultados revelan la importancia de los rasgos conductuales y morfológicos de las especies de colibríes en el uso de recursos según el sexo y que la partición de recursos entre sexos es probablemente un mecanismo importante para reducir la competencia intersexual en los colibríes. Estos resultados ponen de manifiesto la necesidad de comprender mejor el rol que tiene la variación intersexual en los patrones de interacción y en la reproducción de las plantas en las comunidades ecológicas.

Hummingbirds in the Cerrado, the seasonal savannas in Central Brazil, visit both ornithophilous and non-ornithophilous flowers to collect nectar, which is the main source of energy and nutrients to these pollinators. The aim of the present study was to assess the volume, concentration, energy content and sugar composition of nectar collected from 34 hummingbird-visited flower species. We expect that nectar traits of non-ornithophilous species visited by hummingbirds are similar to those of ornithophilous species. Nectar samples were collected from different plant formations in the Cerrado region at Panga Ecological Station, Uberlândia City, Minas Gerais State, Brazil. Samples were obtained from 19 ornithophilous, 10 entomophilous and five chiropterophilous species. Nectar traits, such as volume, sugar concentration and energy content, did not significantly differ between ornithophilous and non-ornithophilous flowers. However, about 80% of the sampled species had sucrose-rich nectar, whereas other species, mainly chiropterophilous, had hexose-rich nectar. Overall, ornithophilous and chiropterophilous flower nectars shared similar energy content. On the other hand, the sugar-chemical composition of nectar from ornithophilous flowers was more similar to that of sucrose-rich entomophilous flowers. There is broad consensus that the nectar in flowers of hummingbird-pollinated species is rich in sucrose. However, hummingbirds visit several savanna plant species unrelated to the ornithophilous pollination syndrome. This trend indicates that hummingbirds show plasticity in selecting plant nectar sources when feeding, mainly in resource-fluctuating environments such as the Cerrado.

Facilitation and competition among plants sharing pollinators have contrasting consequences for plant fitness. However, it is unclear whether pollinator-mediated facilitation and competition may affect pollen limitation (potential contribution of pollination to fitness) in pollination networks. Here, we investigated how pollinator sharing affects pollen limitation in a tropical hummingbird-pollinated community marked by facilitation. We employed indices describing how much a plant species potentially affects the pollination of other co-flowering species through shared pollinators (acting degree) and is affected by other co-flowering species (target degree) within the plant-hummingbird network. Since facilitation often increases pollination quantity but not necessarily quality, we expected both indices to be associated with reductions in pollen limitation estimates that depend on pollination quantity (fruit set and seed number) rather than estimates more strictly related to quality (seed weight and germination). We found that both indices were associated with reductions in pollen limitation only for seed weight and germination. Thus, facilitation occurred via qualitative estimates of pollen limitation. Our results suggest that facilitation may enhance plant fitness estimates even if quantitative components of plant fecundity are already saturated. Overall, we showed that pollinator-mediated indirect effects in a multispecies context are important drivers of plant fitness estimates with consequences for coexistence in diverse communities.

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.

Cities harbour considerable biodiversity and there has been an increased concern about the conservation of pollinators in urban environments. Here, we evaluated how urbanization affects plant-hummingbird interactions at two spatial scales. First, in a medium-sized city from southeastern Brazil (>600,000 inhabitants), we contrasted interaction networks from urban and natural areas, and used artificial nectar feeder stations to evaluate changes in the composition of hummingbird assemblages across an urbanization gradient. Second, we compiled data on six urban plant-hummingbird interaction networks from south and southeastern Brazil to identify the characteristics associated with the most important plants. Locally, urbanization affected hummingbird communities by promoting higher generalization and dominance by more aggressive hummingbirds. Notably, specialized long-billed hermits were absent both in the urban interaction network and at feeder stations from more urbanized areas. Across networks, trees were more important for hummingbirds than shrubs/herbs as were specialized ornithophilous flowers in relation to non-ornithophilous flowers. Plant origin (native or exotic) did not matter. Our results indicate that urban plant-hummingbird communities are organized differently than their counterparts from natural areas, which usually feature key hermits and few trees. Since hermits provide important pollination services, especially for specialized ornithophilous plants, initiatives such as green corridors and preference for native plants with specialized hummingbird-pollinated flowers in urban landscaping may contribute to community restoration and ecosystem functioning.

Patterns in ecology are the products of current factors interacting with history. Nevertheless, few studies have attempted to disentangle the contribution of historical and current factors, such as climate change and pollinator identity and behavior, on plant reproduction. Here, we attempted to separate the relative importance of current and historical processes on geographical patterns of the mating system of the tree species Curatella americana (Dilleniaceae). Specifically, we asked the following: (a) How do Quaternary and current climate affect plant mating system? (b) How does current pollinator abundance and diversity relate to plant mating system? (c) How does mating system relate to fruit/seed quantity and quality in C. americana? We recorded pollinators (richness, frequency, and body size) and performed pollination tests in ten populations of C. americana spread over 3,000 km in the Brazilian savannah. The frequency of self-pollination in the absence of pollinators was strongly influenced by historical climatic instability and not by present-day pollinators. In contrast, seed set from hand-cross and natural pollination were affected by pollinators (especially large bees) and temperature, indicating the importance of current factors on out-cross pollination. Two populations at the Southern edge of the species’ distribution showed high level of hand-cross-pollination and high flower visitation by large bees, but also a high level of autogamy resulting from recent colonization. Our results indicate that historical instability in climate has favored autogamy, most likely as a reproductive insurance strategy facilitating colonization and population maintenance over time, while pollinators are currently modulating the level of cross-pollination.

Made available in DSpace on 2022-05-01T07:58:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-08-01 Temporal constancy of pollination systems is essential for the maintenance of pollinators through time. Community-level assessment of flowering phenology allows understanding variations across seasons and years and the risks of decoupling flowering and pollinators’ activity. We evaluated flowering patterns and temporal diversity of pollination systems in a tropical seasonal forest. We asked whether the temporal organization of flowering times differs among pollination systems; if there is a constancy of pollination systems through the year, since climate and phylogenies constraint flowering time; if there is a prevalent flowering pattern by pollination system, and if the temporal organization of pollination systems by modularity analyses is coherent with grouping by pre-defined seasons. We characterized 10 pollination systems, examined flowering strategies, climate cues and phylogenetic constraints. Pollination by large-to-medium bees dominated (49.2%), followed by diverse insects (22.1%) and flies (14.7%). The remaining systems represented 14% of species. Flowering occurred year-round for most pollination systems, predominating the seasonal flowering strategy. Flowering patterns ranged from aggregated to nested, and random. Climate affected the flowering of most pollination systems, but there was no phylogeny constraint. Modularity grouped pollination systems differently than rainfall seasonality. Contrasting the expectations of reduced temporal constancy, most systems were present year-round, facilitating the exploitation of floral resources by pollinators. Diversity of pollination systems remained constant despite climate seasonality, indicating that several factors influence the optimum flowering time for pollination in seasonally dry vegetations. Global warming may disrupt phenological patterns and the temporal organization of plant communities, a matter for future studies. Departamento de Biodiversidade Laboratório de Fenologia Instituto de Biociências UNESP Universidade Estadual Paulista Departamento de Ecologia Instituto de Biociências Universidade de São Paulo Departamento de Biologia Vegetal Instituto de Biologia CEP Universidade Estadual de Campinas Museu de Diversidade Biológica Universidade Estadual de Campinas Departamento de Biodiversidade Laboratório de Fenologia Instituto de Biociências UNESP Universidade Estadual Paulista

Pollination and reproduction are important processes for understanding plant community dynamics. Information regarding pollination and reproduction is urgent for threatened ecosystems, such as tropical montane ecosystems. In tropical mountains, pollination patterns are expected to conform to the reproductive assurance theory (due to low pollinator activity) and old, climatically buffered and infertile landscapes (OCBIL) theory (due to restricted plant range size). For 82 plant species of the Itatiaia National Park (including endemic and endangered species), we evaluated at least one of the following features: pollinator identity, flower color and size, flowering phenology, and pollinator dependence. Most plant species (ca. 60%) were pollinated by two or more functional groups of pollinators (generalized pollination), with high importance of flies as pollinators. There was low pollinator activity overall (less than one visit per flower per hour). Notably, the invasive honeybee Apis mellifera L. performed half of the visits to this entire plant community, suggesting an impact on the native pollinator fauna and consequently on the native flora. Most endemic plants were generalized with white and small flowers, while endangered species were pollination-specialized with colorful and large flowers. Thus, endangered species are susceptible to changes in pollinator fauna. Flowering seasonality reflected the importance of climatic constraints in this environment. One-third of the plant species were autogamous. Our data suggest that pollinator scarcity may have promoted reproductive assurance strategies such as generalization and pollinator independence. Our community-level study highlighted consistent pollination patterns for tropical mountains and emphasized threats for specialized endangered species.

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

Many deceptive orchids present variation in floral color and fragrance. This might be advantageous for the plant, as it can disturb the associative avoidance learning of pollinators, promoting more visits to the flowers. Some studies have shown that color and fragrance can be correlated in polymorphic deceptive orchids, but these studies employed color traits based on the human visual system and not the visual perception of pollinators. Thus, we investigated the composition of the floral fragrance of Ionopsis utricularioides (Sw.) Lindl., a polymorphic deceptive orchid, and analyzed possible correlations with the floral color as seen by bees, Apis mellifera L. and Melipona quadrifasciata Lepeletier, using the color hexagon model. We found high color and fragrance intraspecific variation, as expected for deceptive species. However, we found no color-fragrance association in individuals, either by comparing fragrance profiles with the color variable saturation or by comparing them with the placement of individuals in the color hexagon for both bee species. This lack of correlation contradicts the biochemical pathway hypothesis, which proposes that associations between floral color and scent in polymorphic flowers arise from shared biochemical pathways. However, a complete absence of correlation between floral signals is consistent with selection arising through pollinator cognitive ecology. Lack of correlation would increase the floral variability perceived by bees, given their multimodal learning, and this variability could disrupt avoidance learning of deceptive flowers, thus enhancing the efficacy of the plant's deceptive pollination mechanism.

Co-flowering plant species may interact via pollinators leading to heterospecific pollen transfer with consequences for plant reproduction. What determines the severity of heterospecific pollen effect on conspecific pollen performance is unclear, but it may depend on the phylogenetic relatedness of the interactors (pollen donors and recipient). The heterospecific pollen effect might also depend on the extent to which plants are exposed to heterospecific pollen over ecological or evolutionary timescales. For instance, generalist-pollinated plant species might tolerate heterospecific pollen more than specialists. Here, we tested whether heterospecific pollen effects are stronger between closely related species than phylogenetically distant ones in a tropical highland community. Then, based on these results, we determined whether responses to heterospecific pollen were stronger in generalized vs. specialized plant species. We applied heterospecific pollen from close (congeneric) or distant (different families) donors alone or with conspecific pollen on stigmas of three recipient species (one generalist, Sisyrinchium wettsteinii; and two specialists, Fuchsia campos-portoi and Fuchsia regia) and scored pollen tube performance in styles. In all species, pollen from closely related donors grew pollen tubes to the base of the style indicating a high potential to interfere with seed set. Conversely, distantly related heterospecific pollen had no effect on either specialist Fuchsia species, whereas enhanced performance of conspecific pollen was observed in generalist S. wettsteinii. The strong effect of phylogenetic relatedness of donor and recipient might have obscured the role of pollination specialization, at least for the three species examined here. Therefore, phylogenetic relatedness mediated the effect of heterospecific pollen on post-pollination success, with possible consequences for reproductive trait evolution and community assembly for further studies to explore., Co-flowering species interact via pollinators leading to heterospecific pollen transfer (pollen from other species) with consequences for plant reproduction. We experimentally demonstrated that phylogenetic relatedness mediated the effect of heterospecific pollen on post-pollination success. Using three species as recipients, we showed that pollen donors of closely related species (same genus) affected pollen-tube growth and had a negative impact on the post-pollination success of the recipient species. However, when pollen donors were distantly related (different family), recipient species tolerated or were even benefited by growing more pollen tubes than without the presence of heterospecific pollen.

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.

Pollinator‐mediated processes (biotic filtering, facilitation or competition) are often inferred by patterns of plant reproductive trait diversity (clustering or evenness of reproductive traits within the community). However, one single pattern can be generated by distinct processes, making difficult to predict the main process of community assembly. Incorporating fitness estimates should improve the link between pattern and process. We investigated patterns of flowering phenology and reproductive traits (floral colour, floral size and anther height) along the season of a pollinator‐depauperated and generalized community. We used data on fitness (pollen receipt and number of pollen tubes) to provide a functional link between trait patterns and assembly mechanisms. We also investigated whether the degree of co‐flowering depended on the floral abundance and pollination functional group (fly‐, bee‐, hummingbird‐pollinated and generalist species) of the plant species. High floral abundance in the flowering season was associated with low trait diversity in the community. Both features increased fitness at the community level. This indicates that similar species are benefited at periods of high floral abundance, probably due to the joint attraction of generalist pollinators in this pollinator‐depauperated community. In general, rare species flowered more synchronously with the community than abundant ones, although distinct patterns emerged depending on the floral trait and pollination functional group. Furthermore, species highly synchronous and possessing similar floral colour in relation to the community had higher fitness indicating that facilitative mechanisms act favouring flowering synchrony and trait similarity. Synthesis. Patterns of flowering synchrony and floral trait similarity indicate pollination facilitation in the studied community. Plants benefited from co‐flowering with species possessing similar floral colour via shared pollinator attraction. Thus, we empirically demonstrated some of the predictions of community assembly theory., This work was supported by FAPESP (grants 2016/06434‐0 and 2018/02996‐0 to P.J.B.), CNPq (grants 436335/2018‐2 to M.W. and 302781/2016‐1 to M.S.) and CAPES (Ph.D. scholarship to N.S.S., Finance Code 001).

Nectar production dynamics can show inter- and intraspecific variation, which can be associated with environmental and ecological factors and with the ultrastructural diversity of the floral nectary. In this context, we recorded nectar production dynamics from a morphofunctional perspective using the hummingbird-pollinated Billbergia distachia (Bromeliaceae). The scale-throated hermit Phaethornis eurynome was the only floral visitor observed, indicating a specialized pollination system. Nectar production showed significant differences between day and night, and the periods of major pollinator activity and nectar secretion were synchronous. The ultrastructural features of the nectary showed some evidence of nectar reabsorption in flowers at night, and it can be inferred that this process may be a key factor in the nocturnal pause in nectar production. In this way, nectary morphoanatomy, nectar traits and an energy-saving mechanism through nectar reabsorption contribute to the well-established relationship between B. distachia and P. eurynome.

Pollination is thought to be under positive density‐dependence, destabilising plant coexistence by conferring fitness disadvantages to rare species. Such disadvantage is exacerbated by interspecific competition but can be mitigated by facilitation and intraspecific competition. However, pollinator scarcity should enhance intraspecific plant competition and impose disadvantage on common over rare species (negative density‐dependence, NDD). We assessed pollination proxies (visitation rate, pollen receipt, pollen tubes) in a generalised plant community and related them to conspecific and heterospecific density, expecting NDD and interspecific facilitation due to the natural pollinator scarcity. Contrary to usual expectations, all proxies indicated strong intraspecific competition for common plants. Moreover interspecific facilitation prevailed and was stronger for rare than for common plants. Both NDD and interspecific facilitation were modulated by specialisation, floral display and pollinator group. The combination of intraspecific competition and interspecific facilitation fosters plant coexistence, suggesting that pollination can be a niche axis maintaining plant diversity., This work was supported by FAPESP (grants 2016/06434‐0 and 2018/02996‐0 to P.J.B.), CNPq (grants 436335/2018‐2 to M.W. and 302781/2016‐1 to M.S.) and CAPES (Ph.D. scholarship to N.S.S., Financial Code 001).

Animal-pollinated flowers may orient resources for competing activities, such as nectar production for attracting flower visitors but then saving nectar (through inhibiting nectar production or by final resorption) for the subsequent maturation of fruits and seeds. Nectar production is continuous in Nicotiana longiflora and N. alata after flower opening, but early nectar removal reduces total secreted nectar. Resource trade-off between nectar investment and seed production were experimentally assessed in manually pollinated flowers experiencing different numbers of repeated nectar removals, while controlling for maternal effects. We expected that flowers with less nectar secretion produce larger seed sets. The results showed that for both species the earlier the nectar removal during flower anthesis, the lower the total nectar secreted and the higher the mass of seeds produced. This general pattern was clearer for N. longiflora. The link between decreased nectar production and the subsequent increase in the seed set implies that resources are limited. Consequently, nectar savings during the pollination process through early nectar removal by pollinators can be interpreted as a trade-off between resources secreted by flowers for pollinator attraction and those utilized during fruit and seed maturation. Fil: Galetto, Leonardo. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Araujo, Francielle Paulina. Universidade Estadual do Rio Grande do Sul; Brasil Fil: Grilli, Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Amarilla, Leonardo. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Torres, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba; Argentina Fil: Sazima, Marlies. Universidade Estadual de Campinas; Brasil

This study describes the floral phenology and morphology, reproductive biology and pollinators for eight legume tree species, Schizolobium parahyba, Senna macranthera, and Senna multijuga (Caesalpinioideae), as well as Andira fraxinifolia, Lonchocarpus cultratus, Pterocarpus violaceus, Swartzia oblata, and S. simplex (Papilionoideae), in the Atlantic Forest in Southeast Brazil. All the studied species showed an annual flowering pattern, and almost all are of the cornucopia-flowering type, with the only exception being Swartzia oblata, which was of the steady-state type. In general, the legume flowers studied are conspicuous, mostly medium-sized, and offer nectar and/or pollen as a resource. Self-incompatibility associated with the production of many flowers and consequent pollen discounting due to self-pollination may contribute to low fruit set of these species in natural conditions. Fifty bee species were recorded visiting the flowers, with medium to large-sized Apidae bees, such as Bombus morio, and species of Xylocopa, Centridini and Euglossina, which were among the most frequent visitors and major pollinators. These bees showed high floral constancy, thus they are significant to the reproductive success of these tree species. This study provides information regarding the interactions between bees and these eight legume species and evaluates the importance of pollinators for their sexual reproduction.

Premise of research. The relations between orchids and their pollinators are so specialized that the pollination of some of these flowers depends solely on specific groups of bees. Members of Stanh...

Premise of research. Nectar robbers can affect pollinator behavior and indirectly affect plant fitness. The signal of such effects (positive, neutral, or negative) may depend on how the primary pollinators of a given plant species respond to robbed flowers. Comparative studies are important to give insight on which factors are linked to these differential outcomes of nectar robbing on plant reproductive success. Here, we investigated the effect of a common Neotropical nectar robber, the stingless bee, Trigona spinipes (Apidae), on the reproductive success of the bee-pollinated Crotalaria vitellina (Fabaceae) and the hummingbird-pollinated Besleria longimucronata (Gesneriaceae).Methodology. We compared the robbing rate (number of flowers robbed relative to total flower display) between species and evaluated the effect of robbing on plant reproductive success by comparing the seed number per fruit of robbed fruits (identified by the presence of scars in the calyx, caused by the robber) with that of intact f...

Flowers that provide only pollen to pollinators should maximize pollen release for reproduction while minimizing pollen loss through consumption by bees. In flowers that are polymorphic for stamen type, the number of pollen grains produced as well as stamen morphology likely influences pollen release dynamics and favor the division of labor between stamens with different functions. However, few studies have evaluated such predictions. In this study, we tested the “division of labor hypothesis” considering not only the stamen morphology of pollen flowers but also their pollen release dynamics. Stamen morphology as well as the amount and viability of pollen were characterized in two Melastomataceae species, Pleroma granulosum and Pleroma raddianum. Using artificial vibrations, we estimated pollen release dynamics throughout anthesis in the anthers of short and long stamens from flowers of both species. P. granulosum flowers presented low heteranthery (i.e., anthers differed by only about 1 mm in length) and short stamens produced fewer pollen grains in both species. We also found similarly high viability of pollen from all anthers of both species. Although pollen grain release increased in all anthers over the flower´s lifespan, their dynamics were different between the two stamen sets in both species. Anthers of shorter stamens tended to release fewer and proportionally lower quantities of pollen grains at each time interval than anthers of longer stamens. Our study suggests that the number of pollen grains produced, as well as stamen morphology (beyond anther size) may control pollen release dynamics, leading to a division of labor between stamens in these pollen flowers.

Flowering and fruiting are key events in the life history of plants, and both are critical to their reproductive success. Besides the role of evolutionary history, plant reproductive phenology is regulated by abiotic factors and shaped by biotic interactions with pollinators and seed dispersers. In Melastomataceae, a dominant Neotropical clade, the reproductive systems vary from allogamous with biotic pollination to apomitic, and seed dispersal varies from dry (self-dispersed) to fleshy fruits (animal-dispersed). Such variety of reproductive strategies is likely to affect flowering and fruiting phenologies. In this study, we described the reproductive phenology of 81 Melastomataceae species occurring in two biodiversity hotspots: the Atlantic rainforest and the campo rupestre. We aim to disentangle the role of abiotic and biotic factors defining flowering and fruiting times of Melastomataceae species, considering the contrasting breeding and seed dispersal systems, and their evolutionary history. In both vegetation types, pollinator-dependent species had a higher flowering seasonality than pollinator-independent ones. Flowering patterns also presented phylogenetic signal regardless of vegetation type. Fruiting of fleshy-fruited species was seasonal in campo rupestre but not in Atlantic rainforest; the fruiting of dry-fruited species was also not seasonal in both vegetation. Fruiting showed a low phylogenetic signal, probably because the influence of environment and dispersal agents on fruiting time is stronger than the phylogenetic affinity. Considering these ecophylogenetic patterns, our results indicate that flowering may be shaped by the different reproductive strategies of Melastomataceae lineages, while the fruiting patterns may be governed mainly by the seed dispersal strategy and flowering time, with smaller phylogenetic influence. This article is protected by copyright. All rights reserved.