TROPICAL FRUGIVOROUS BIRDS MOLT AND BREED IN RELATION TO THE AVAILABILITY OF FOOD RESOURCES

ABSTRACT ∙ Few studies have investigated how the abundance of food resources influences the phenology of the annual cycles of tropical birds. Frugivorous birds are good models for such investigation because the abundance of their main food types, fruits and arthropods, vary independently from each other. We investigated how the consumption and availability of fruits and arthropods are related to breeding and molt cycles of frugivorous birds in a fragmented landscape of the Brazilian Atlantic forest. We recorded the occurrence of brood patches and the molting of flight feathers in mist‐netted birds, from which we also analyzed the contents of fecal samples. Using nonparametric and parametric correlation tests we investigated the relationships among breeding and molt stage with the availability of fruits and arthropods. We found that the availability of fruits and arthropods fluctuates temporally and independently, but both food sources have shortage periods, apparently more pronounced for fruits. During periods when fruit was scarce, birds relied more heavily on arthropods as food. Incubation occurred when fruit availability was high, whereas the molt period that followed was coincident with the availability of arthropods. Although our observational study does not permit definite conclusions regarding the relationship between food availability and the timing of the annual cycle events investigated, it is suggestive that avian breeding and molt cycles coincide with fruit and arthropod availability, respectively. Together with arthropods, fruits are important for nestlings of frugivorous birds, and protein from arthropods may be especially important for the development of new feathers.RESUMO ∙ Relação entre disponibilidade de alimento, muda de penas e reprodução de aves frugívoras Poucos estudos abordaram a influência da abundância de recursos alimentares sobre a fenologia do ciclo anual de aves tropicais. Aves frugívoras são bons modelos para esse propósito porque as abundâncias dos seus principais alimentos, frutas e artrópodes, podem variar no tempo de maneira independente. Neste trabalho investigamos como os ciclos de muda de penas de voo e reprodução estão relacionados com a disponibilidade e o consumo de frutos e artrópodes em uma paisagem fragmentada de Mata Atlântica. Para isso registramos a ocorrência de placa de choco e mudas nas penas de voo de aves capturadas em redes de neblina e sua relação temporal com a disponibilidade de frutos e artrópodes amostrados nas áreas das redes. A disponibilidade de frutos e artrópodes apresentaram flutuações temporais independentes, porém ambos apresentaram períodos de escassez, aparentemente mais pronunciado para os frutos. Durante períodos de escassez de frutos, as aves consumiram mais artrópodes. O período de incubação ocorreu quando a disponibilidade de frutos era maior, enquanto a muda de penas coincidiu com o período de maior disponibilidade de artrópodes. Embora nosso estudo observacional não permita conclusões definitivas sobre a relação entre a disponibilidade de alimentos e os eventos de ciclo anual investigados, é sugestivoque os períodos de reprodução e muda tenham coincidido com maior disponibilidade de frutos e artrópodes, respectivamente. Juntamente com artrópodes, frutos podem ser importantes para a criação dos filhotes das aves frugívoras, enquanto proteína proveniente dos artrópodes pode ser especialmente importante para o desenvolvimento de novas penas.

THE DEGREE OF FRUGIVORY OF BIRDS AS ESTIMATED FROM GASTRIC AND FECAL SAMPLES

The degree of frugivory (DF) has long been used to characterize the relative importance of fruits to the diet of a bird and, more recently, as a functional trait related to the role of birds in seed dispersal networks. Although quantitative estimations of DF are desirable, general, categorical classifications or coarse estimations of diet composition based in qualitative information are often used. Data on stomach, fecal and regurgitation contents scattered in the literature or easily obtained in the field could be used to provide a quantitative, potentially more reliable assessment of DF. We compiled such data from the literature and our own fieldwork to obtain 12,576 samples for 985 Neotropical bird species, of which 489 species (49.6%) from 61 families had at least one fruit-containing sample. Gastric (i.e. stomach plus regurgitation) and fecal samples provided similar estimates of DF, despite potential differences in the degree of food digestion. The DF we obtained were higher than those presented in the most frequently used source of quantitative DF estimates in the literature (the Elton Traits database). We further explored with a few study cases the utility of stomach, fecal and regurgitation samples to evaluate intraspecific geographic, sexual, and ontogenetic variations in DF, topics rarely investigated so far. We argued that stomach, fecal and regurgitation sample data abundantly available in the literature or obtained from mist-netted birds may be used to produce quantitative assessments of DF likely more reliable than the estimates used so far and useful for a plethora of ecological studies

Joint species movement modeling : how do traits influence movements?

Joint species distribution modeling has enabled researchers to move from species-level to community-level analyses, leading to statistically more efficient and ecologically more informative use of data. Here, we propose joint species movement modeling (JSMM) as an analogous approach that enables inferring both species- and community-level movement parameters from multispecies movement data. The species-level movement parameters are modeled as a function of species traits and phylogenetic relationships, allowing one to ask how species traits influence movements, and whether phylogenetically related species are similar in their movement behavior. We illustrate the modeling framework with two contrasting case studies: a stochastic redistribution model for direct observations of bird movements and a spatially structured diffusion model for capture-recapture data on moth movements. In both cases, the JSMM identified several traits that explain differences in movement behavior among species, such as movement rate increasing with body size in both birds and moths. We show with simulations that the JSMM approach increases precision of species-specific parameter estimates by borrowing information from other species that are closely related or have similar traits. The JSMM framework is applicable for many kinds of data, and it facilitates a mechanistic understanding of the causes and consequences of interspecific variation in movement behavior.Peer reviewe

Global and regional ecological boundaries explain abrupt spatial discontinuities in avian frugivory interactions

Species interactions can propagate disturbances across space via direct and indirect effects, potentially connecting species at a global scale. However, ecological and biogeographic boundaries may mitigate this spread by demarcating the limits of ecological networks. We tested whether large-scale ecological boundaries (ecoregions and biomes) and human disturbance gradients increase dissimilarity among plant-frugivore networks, while accounting for background spatial and elevational gradients and differences in network sampling. We assessed network dissimilarity patterns over a broad spatial scale, using 196 quantitative avian frugivory networks (encompassing 1496 plant and 1004 bird species) distributed across 67 ecoregions, 11 biomes, and 6 continents. We show that dissimilarities in species and interaction composition, but not network structure, are greater across ecoregion and biome boundaries and along different levels of human disturbance. Our findings indicate that biogeographic boundaries delineate the world’s biodiversity of interactions and likely contribute to mitigating the propagation of disturbances at large spatial scales.The authors acknowledge the following funding: University of Canterbury Doctoral Scholarship (L.P.M.); The Marsden Fund grant UOC1705 (J.M.T., L.P.M.); The São Paulo Research Foundation - FAPESP 2014/01986-0 (M.G., C.E.), 2015/15172-7 and 2016/18355-8 (C.E.), 2004/00810-3 and 2008/10154-7 (C.I.D., M.G., M.A.P.); Earthwatch Institute and Conservation International for financial support (C.I.D., M.G., M.A.P.); Carlos Chagas Filho Foundation for Supporting Research in the Rio de Janeiro State – FAPERJ grant E-26/200.610/2022 (C.E.); Brazilian Research Council grants 540481/01-7 and 304742/2019-8 (M.A.P.) and 300970/2015-3 (M.G.); Rufford Small Grants for Nature Conservation No. 22426–1 (J.C.M., I.M.), No. 9163-1 (G.B.J.) and No. 11042-1 (MCM); Universidade Estadual de Santa Cruz (Propp-UESC; No. 00220.1100.1644/10-2018) (J.C.M., I.M.); Fundação de Amparo à Pesquisa do Estado da Bahia - FAPESB (No. 0525/2016) (J.C.M., I.M.); European Research Council under the European Union’s Horizon 2020 research and innovation program (grant 787638) and The Swiss National Science Foundation (grant 173342), both awarded to C. Graham (D.M.D.); ARC SRIEAS grant SR200100005 Securing Antarctica’s Environmental Future (D.M.D.); German Science Foundation—Deutsche Forschungsgemeinschaft PAK 825/1 and FOR 2730 (K.B.G., E.L.N., M.Q., V.S., M.S.), FOR 1246 (K.B.G., M.S., M.G.R.V.) and HE2041/20-1 (F.S., M.S.); Portuguese Foundation for Science and Technology - FCT/MCTES contract CEECIND/00135/2017 and grant UID/BIA/04004/2020 (S.T.) and contract CEECIND/02064/2017 (L.P.S.); National Scientific and Technical Research Council, PIP 592 (P.G.B.); Instituto Venezolano de Investigaciones Científicas - Project 898 (V.S.D.)

ATLANTIC BIRDS: a data set of bird species from the Brazilian Atlantic Forest

South America holds 30% of the world's avifauna, with the Atlantic Forest representing one of the richest regions of the Neotropics. Here we have compiled a data set on Brazilian Atlantic Forest bird occurrence (150,423) and abundance samples (N = 832 bird species; 33,119 bird individuals) using multiple methods, including qualitative surveys, mist nets, point counts, and line transects). We used four main sources of data: museum collections, on-line databases, literature sources, and unpublished reports. The data set comprises 4,122 localities and data from 1815 to 2017. Most studies were conducted in the Florestas de Interior (1,510 localities) and Serra do Mar (1,280 localities) biogeographic sub-regions. Considering the three main quantitative methods (mist net, point count, and line transect), we compiled abundance data for 745 species in 576 communities. In the data set, the most frequent species were Basileuterus culicivorus, Cyclaris gujanensis, and Conophaga lineata. There were 71 singletons, such as Lipaugus conditus and Calyptura cristata. We suggest that this small number of records reinforces the critical situation of these taxa in the Atlantic Forest. The information provided in this data set can be used for macroecological studies and to foster conservation strategies in this biodiversity hotspot. No copyright restrictions are associated with the data set. Please cite this Data Paper if data are used in publications and teaching events. © 2017 by the Ecological Society of Americ

ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

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. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ

Estudo comparado da dispersão e predação de sementes de Cabralea canjerana (Meliaceae) em duas areas de mata do Estado de São Paulo

Orientador: Wesley Rodrigues SilvaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: O estudo de dispersão e predação de sementes fornece subsídios para entender a estrutura e dinâmica das comunidades vegetais, pois desses dois fenômenos depende, em parte, o estabelecimento das plântulas e, conseqüentemente, o sucesso reprodutivo das plantas. Este estudo investiga e compara o sistema de dispersão de uma espécie arbórea cujas sementes ariladas são dispersas por aves, Cabralea canjerana (Meliaceae), em duas áreas de mata do Estado de São Paulo: a Fazenda Intervales (FI), e a Mata de Santa Genebra (MSG). A primeira área é uma reserva com 38000 ha de Floresta Atlântica (sensu strictu) relativamente bem preservada, enquanto a MSG é um fragmento de Floresta Semidecídua do Planalto Paulista com 250 ha, cuja avifauna encontra-se empobrecida. A maioria das espécies de aves observadas engole as sementes ariladas, retêm o arilo, e as regurgita intactas, porém sem o arilo. Assim, as aves contribuem para a germinação das sementes, pois a presença do arila propicia a infestação por fungos que prejudica a germinação. Na FI, os frutos de C. canjerana foram aproveitados como alimento por trinta e cinco espécies de aves, e o principal dispersor foi Titvra cavana (Cotingidae). No entanto, várias outras espécies exerceram um papel importante na dispersão das sementes. Na MSG, por outro lado, catorze espécies alimentaram-se dos frutos. Nesta área, empobrecida em avifauna, Q. Janjerana parece depender em grande parte de Vireo chivi (Vireonidae) para a dispersão de suas sementes. Esta espécie de ave no entanto, derruba parte das sementes que consegue coletar e, provavelmente, deposita sementes em locais impróprios para a germinação. Na FI, as sementes no solo são intensamente atacadas por roedores e insetos predadores. Estes últimos atacam preferencialmente as sementes depositadas nas proximidades da planta-mãe. Sementes ariladas que caem sob as copas são removidas por formigas Ponerinae, que podem atuar como dispersores secundários de sementes. Na MSG a predação por insetos é menor que na FI e, devido à baixa densidade de roedores relacionada ao processo de fragmentação, o papel de vertebrados predadores de sementes parece ser exercido por aves granivoras de solo, abundantes na área. Formigas Ponerinae, que também removem sementes ariladas na MSG, podem ter um papel mais importante nesta área que na FI, devido ao menor número de agentes dispersores e a ineficiência de alguns deles na remoção das sementes. Algumas das diferenças encontradas entre os sistemas de dispersão de C. canjerana na FI e MSG podem ser o resultado da fragmentação e isolamento desta última área, que levou ao atual grau de empobrecimento das comunidades animal e vegetalAbstract: Seed dispersal and seed predation studies are important to clarify our knowledge about the structure and dynamic of plant communities because both phenomena are directly related to seedling establishment and, ultimately, to plant reproductive success. This study investigates and compares the seed dispersal system of a neotropical tree whose arillated seeds are dispersed by birds, Cabralea canjerana (Meliaceae), in two forested areas located in São Paulo State, southeastern Brazil. The first study site, Fazenda Intervales (FI). is a 38,000 ha reserve composed mostly by pristine Atlantic Forest. The second one, Mata de Santa Genebra (MSG), is a 250 ha fragment of semideciduous forest whose bird fauna is nowadays markedly different from the original composition, in part as a consequence of the fragmentation process. Most bird species observed visiting the study trees swallow arillated seeds whole, and regurgitate intact seeds without arils. Acting in this way, they promote the germination of the seeds, which otherwise will fail to germinate due to fungi infestation. At FI thirty-five bird species ate the fruits of C. canjerana. Black-tailed Tityra (Titvra cayana, Cotingidae) was the main seed disperser, but several other species were also important as seed dispersers. In contrast, at MSG C. canjerana fruits were eaten by only fourteen bird species. At this area, the Red-eyed Vireo (Vireo chivi, Vireonidae) was the most important seed disperser, but it was also a "waster" because it often dropped seeds beneath the parent plant, and also carried some of them to unsuitable sites for germination. At FI, seeds exposed on the forest floor are heavily attacked by rodents and insect predators. The latter destroy mainly seeds deposited near parent plants. Arillated seeds that eventually drop beneath the parent plants are removed by Ponerinae Arillated seeds that ants which can act as secondary seed dispersers. At MSG, insect predation seems to be less important than at FI. In addition, the rodent density at this area seems to be unusually small (probably due to fragmentation), and the role of vertebrate seed predators may be performed by ground granivorous birds. Given the low number of primary seed disperser agents and the relatively inefficiency of some of them in removing the seeds, Ponerinae ants, that also remove arillated seeds at MSG, may be relatively more important seed dispersers at this area than at FI. Some of the differences observed between the seed dispersal systems of C. canjerana at FI and MSG may be the result of the fragmentation and isolation of the latter area, which led to the degradation of its animal and plant communitiesMestradoEcologiaMestre em Ciências Biológica

Interação formiga-planta em solo de Mata Atlantica : influencia das formigas na ecologia de frutos e sementes não-mirmecocoricas

Orientador: Paulo Sergio Moreira Carvalho de OliveiraTese (doutorado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: Este estudo trata das interações entre formigas e diásporos não-mirmecocóricos no chão de uma floresta Atlântica (Parque Estadual Intervales) no sudeste do Brasil. Conduzido entre abril de 1995 e junho de 1997, o estudo foi dividido em três partes que abordam as duas formas pelas quais os diásporos não-mirmecocóricos tomam-se disponiveis para as formigas que frequentam o chão da floresta: (1) caídos das árvores (Capítulos 1 e 2) e (2) contidos nas fezes de vertebrados frugívoros (Capítulo 3). O Capítulo 1 relata o levantamento das interações entre formigas e diásporos não-mirmecocóricos feito durante dois anos ao longo de um transecto de 5 km amostrado mensalmente. Um total de 886 interaçôes envolvendo 37 espécies de formigas e 56 diásporos foram registradas. O número de interações registrado mensalmente não esteve correlacionado nem com a temperatura média nem com a pluviosidade mensais que, no entanto, estiveram positivamente correlacionadas com o número de espécies de formigas registrado nas interações. Possíveis padrões de variação sazonal no uso de diásporos pelas formigas podem ter sido mascarados pelo uso constante deste recurso pelas duas espécies de formigas mais abundantes na área de estudo (uma Pheidole e uma Solenopsis), e pela frutificação massiça de algumas plantas cujos diásporos são especialmente atrativos para as formigas. No capítulo 2, seis plantas não-mirmecocóricas (Virqla oleifera, Eugenia stictosepala, Cabralea canjerana, Citharexylum myrianthum, Alchomea glandulosa e Hyeronima alchorneoides), cujos diásporos diferem em tamanho e conteúdo lipídico, foram selecionadas para a investigação de como estas características afetam a interação formiga-diásporo. As formigas rapidamente descobriram e limparam (i. e., removeram a polpa ou arilo) os diásporos colocados no chão da floresta. A taxa de recrutamento e a presença das formigas foi maior para os diásporos ricos em lipídeos do que para aqueles pobres em lipídeos. A taxa de remoção e a distância média de deslocamento foi maior para os diásporos pequenos. A formiga Ponerinae Pachycondyla striata, uma das que mais frequentemente explorou os diásporos ricos em lipídeos, transportou estes diásporos para seus ninhos e, posteriormente, abandonou-os limpos e intactos nos "depósitos de lixo" localizados fora dos ninhos. Testes de germinação com diásporos limpos e "não-limpos" revelaram que a remoção da polpa ou arilo aumenta o sucesso de germinação em Virola oleifera, Cabralea canjerana, Citharexylum myrianthum e Alchornea glandulosa. Um análise por cromatografia gasosa revelou que a composição de ácidos graxos dos arilos estudados era bastante semelhante à do elaiossomo de uma semente mirmecocórica típica (Ricinus communis), corroborando assim a hipótese de que alguns arilos e elaiossomos são estruturas quimicamente semelhantes. No Capítulo 3, a remoção por formigas de três espécies de sementes (Philodendron corcovadensis e P. apendiculatum - Araceae e Aechmea sp. - Bromeliaceae) naturalmente encontradas nas fezes de macacos-prego (Cebus apella) foi investigada no sub-bosque e em cinco clareiras. A variação na taxa de remoção entre as sementes pesquisadas, entre sub-bosque e clareiras e também entre as várias clareiras (que diferiam em tamanho e estágio sucessional), foi abordada. Dezessete espécies de formigas (4 subfamílias, 9 gêneros) foram registradas nas fezes, oito das quais removeram sementes. Após 24 h de exposição às formigas, 68 % das sementes foram removidas das porções experimentais de fezes que continham 15 sementes. A espécie de semente afetou a taxa de remoção tanto na comparação sub-bosque vs. clareiras quanto na comparação entre clareiras, enquanto o sítio de deposição das fezes não teve nenhum efeito. Estes resultados podem ser interpretados como consequência do efeito "igualador" que três espécies de formigas Myrmicinae (Pheidole spp.) tiveram sobre a remoção das sementes das fezes. Estas espécies foram responsáveis pela maior parte das interações formiga-semente observadas (77 % no sub-bosque e nas clareiras) e estão entre as mais abundantes formigas do chão da floresta tanto no sub-bosque quanto nas clareiras. Concluindo, interações entre formigas e diásporos não-mirmecocóricos encontrados no chão da floresta são comuns, especialmente em matas úmidas de baixada que combinam grande abundância de formigas com disponibilidade anual de diásporos. O tamanho e conteúdo lipídico dos diásporos são fatores determinantes para o resultado destas interações. Devido a grande abundância de formigas em florestas neotropicais, e a flexibilidade que algumas delas apresentam em relação ao gradiente microclimático que exploram, a remoção de sementes das fezes de vertebrados frugívoros é menos afetada pelas diferenças nas condições microclimáticas entre sub-bosque e clareiras do que pela espécie de semente envolvidaAbstract: This study investigates the interaction between ants and non-myrmecochorous diaspores in a lowland Atlantic rain forest (Parque Estadual Intervales) in southeast Brazil. The study, conducted between April 1995 and June 1997, was divided into three parts which explore both ways through which nonmyrmecochorous diaspores become available to litter-foraging ants: (1) falling from parent plants (Chapters 1 and 2), and (2) embedded in vertebrate frugivore feces (Chapter 3). Chapter 1 reports a survey of the ant-nonmyrmecochorous diaspore interactions carried out during two years along a 5-km transect sampled monthly. A total of 886 interactions involving 37 ant species and 56 different diaspores were recorded. No seasonal pattern of diaspore use by ants became clear. The monthly number of interactions was not significantly correlated either with rainfall or mean temperature. The number of ant species recorded in the interactions, however, was associated with these climatic parameters. Any seasonal pattern of diaspore use by the ant community may have been masked by the year-round use of diaspores by the two most common litter-foraging ant species in the study site (one Pheido/e and one So/enopsis), and by the massive and episodic fruiting of some plant species whose diaspores are especially attractive to ants. In Chapter 2, six nonmyrmecochorous plant species (Virola oleifera, Eugenia stictosepala, Cabralea canjerana, Citharexylum myrianthum. Alchornea g/andu/osa and Hyeronima alchorneoides) whose diaspores differ in size and lipid content were selected to investigate how these features affect the outcome of ant-diaspore interactions. Ants were in general rapid at discovering and cleaning the diaspores (Le., removal ofpulp or aril). Recruitment rate and ant attendance were higher for lipid-rich diaspores than for lipid-poor ones. Removal rate and displacement distance were higher for small diaspores. The large ponerine antPachycondyla striata, one of the most frequent attendants to lipid-rich arillate diaspores, transported the latter into their nests and discarded cleaned intact seeds on refuse piles outside the nest. Gennination tests with c1eaned and unc1eaned diaspores revealed that the removal of pulp or aril may increase germination success in Virola oleifera, Cabralea canjerana, Citharexylum myrianthum and A/chornea g/andu/osa. Gas chromatography analyses revealed a close similarity in the fatty acid composition of the arils of the lipid-rich diaspores and the elaiosome of a typical myrmecochorous seed (Ricinus communis), corroborating the suggestion that some arils and elaiosomes are chemically similar structures. In Chapter 3, the removal of three seed species-(Phi/odendron corcovadensis andP. apendicu/atumAraceae, and Aechmea sp. - Bromeliaceae) from the feces of Capuchin monkeys (Cebus ape//a) by ants in the understory and in five treefall gaps was investigated. I asked if seed removal varied among seed species, between understory and gaps, and also among gaps differing in size and age. Seventeen ant species (4 subfamilies, 9 genera) were recorded on the feces, eight of which were observed removing seeds. On average, 68 % of the seeds were removed from the feces portions containing 15 seeds each after 24 h. For both the understory vs. gap and the among-gap comparisons seed species significantly affected the proportion of seeds removed, while deposition site had no effect. These results can be interpreted as a consequence of the equalizing effect that three myrmicine ants (Pheidole spp.) had upon seed removal. These species were responsible for the bulk of ant-seed interactions observed (77 % in the both understory and gaps sites) and figure among the most abundant litter-foraging ants in the understory and gaps. In conc1usion, interactions between ants and fallen nonmyrmecochorous diaspores is common, especially in lowland rainforests where the abundance of ants is coupled with the year-round availability of fleshy diaspores. The size and the lipid-content of the diaspores are major determinants of the outcome of such interactions. Due to the high abundance of ants in neotropical forests, and the flexibility of some ant species in the microclimatic gradient they use, seed removal from vertebrate frugivore feces is likely to be less affected by differences in microclimatic conditions between understory and gaps than by the seed species involved.DoutoradoEcologiaDoutor em Ciência