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Despite their ancient past and high diversity, African populations are the least represented in human population genetic studies. In this study, uniparental markers (mtDNA and Y chromosome) were used to investigate the impact of sociocultural factors on the genetic diversity and inter-ethnolinguistic gene flow in the three major Nigerian groups: Hausa (n = 89), Yoruba (n = 135) and Igbo (n = 134). The results show a distinct history from the maternal and paternal perspectives. The three Nigerian groups present a similar substrate for mtDNA, but not for the Y chromosome. The two Niger-Congo groups, Yoruba and Igbo, are paternally genetically correlated with populations from the same ethnolinguistic affiliation. Meanwhile, the Hausa is paternally closer to other Afro-Asiatic populations and presented a high diversity of lineages from across Africa. When expanding the analyses to other African populations, it is observed that language did not act as a major barrier to female-mediated gene flow and that the differentiation of paternal lineages is better correlated with linguistic than geographic distances. The results obtained demonstrate the impact of patrilocality, a common and well-established practice in populations from Central-West Africa, in the preservation of the patrilineage gene pool and in the affirmation of identity between groups.

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Similar to other South American regions, Tierra del Fuego has an admixed population characterized by distinct ancestors: Native Americans who first occupied the continent, European settlers who arrived from the late 15th century onwards, and Sub-Saharan Africans who were brought to the Americas for slave labor. To disclose the paternal lineages in the current population from Tierra del Fuego, 196 unrelated males were genotyped for 23 Y-STRs and 52 Y-SNPs. Haplotype and haplogroup diversities were high, indicating the absence of strong founder or drift events. A high frequency of Eurasian haplogroups was detected (94.4%), followed by Native American (5.1%) and African (0.5%) ones. The haplogroup R was the most abundant (48.5%), with the sub-haplogroup R-S116* taking up a quarter of the total dataset. Comparative analyses with other Latin American populations showed similarities with other admixed populations from Argentina. Regarding Eurasian populations, Tierra del Fuego presented similarities with Italian and Iberian populations. In an in-depth analysis of the haplogroup R-M269 and its subtypes, Tierra del Fuego displayed a close proximity to the Iberian Peninsula. The results from this study are in line with the historical records and reflect the severe demographic change led mainly by male newcomers with paternal European origin.

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Immigrants from diverse origins have arrived in Paraguay and produced important demographic changes in a territory initially inhabited by indigenous Guarani. Few studies have been performed to estimate the proportion of Native ancestry that is still preserved in Paraguay and the role of females and males in admixture processes. Therefore, 548 individuals from eastern Paraguay were genotyped for three marker sets: mtDNA, Y-SNPs and autosomal AIM-InDels. A genetic homogeneity was found between departments for each set of markers, supported by the demographic data collected, which showed that only 43% of the individuals have the same birthplace as their parents. The results show a sex-biased intermarriage, with higher maternal than paternal Native American ancestry. Within the native mtDNA lineages in Paraguay (87.2% of the total), most haplogroups have a broad distribution across the subcontinent, and only few are concentrated around the Paraná River basin. The frequency distribution of the European paternal lineages in Paraguay (92.2% of the total) showed a major contribution from the Iberian region. In addition to the remaining legacy of the colonial period, the joint analysis of the different types of markers included in this study revealed the impact of post-war migrations on the current genetic background of Paraguay.

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San Basilio de Palenque is an Afro-descendant community near Cartagena, Colombia, founded in the sixteenth century. The recognition of the historical and cultural importance of Palenque has promoted several studies, namely concerning the African roots of its first inhabitants. To deepen the knowledge of the origin and diversity of the Palenque parental lineages, we analysed a sample of 81 individuals for the entire mtDNA Control Region as well as 92 individuals for 27 Y-STRs and 95 for 51 Y-SNPs. The results confirmed the strong isolation of the Palenque, with some degree of influx of Native American maternal lineages, and a European admixture exclusively mediated by men. Due to the high genetic drift observed, a pairwise FST analysis with available data on African populations proved to be inadequate for determining population affinities. In contrast, when a phylogenetic approach was used, it was possible to infer the phylogeographic origin of some lineages in Palenque. Contradicting previous studies indicating a single African origin, our results evidence parental genetic contributions from widely different African regions.

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The use of Y-chromosomal genetic markers in forensic investigations demands the establishment of reliable and representative DNA databases of different reference populations. The genetic characterization of the Y chromosome variation in human populations requires the analyses of haplotype frequencies allied to haplogroup determination. The present study aimed to contribute to the Brazilian database by providing 1,382 Yfiler Plus individual profiles, from 11 Brazilian states. The Yfiler Plus markers showed high haplotype diversities in all Brazilian populations (>0.9970), allowing high intra-population discrimination in forensic investigations. Pairwise genetic distances showed a homogeneity between Brazilian populations (FST ≤ 0.0043; non-differentiation p-values ≥ 0.0212), indicating that admixed populations from Brazil can be represented in a single Yfiler Plus haplotype database, for forensic purposes. The performance of Haplogroup Predictor and NevGen software in haplogroup prediction based on Yfiler Plus and Yfiler haplotypes was evaluated in a subset of 416 Brazilian samples that were also genotyped for 51 Y-SNPs. In 25% of the samples, no classification or errors were found for at least one of the prediction tools or marker sets. NevGen presented lower error rates (5.52% and 8.65% with Yfiler Plus and Yfiler, respectively) than Haplogroup Predictor (16.11% with Yfiler Plus and 13.70% with Yfiler). In conclusion, both haplogroup prediction tools can be useful to direct the SNP typing, but present large error rates to be used in forensic analysis, especially in predicting African haplogroups in admixed South American populations.

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Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the intermixing (admixture) of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods, here we infer sub-continental ancestry in over 6,500 Latin Americans and evaluate the impact of regional ancestry variation on physical appearance. We find that Native American ancestry components in Latin Americans correspond geographically to the present-day genetic structure of Native groups, and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming mostly from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that ancestry related to highland (Central Andean) versus lowland (Mapuche) Natives is associated with variation in facial features, particularly nose morphology, and detect significant differences in allele frequencies between these groups at loci previously associated with nose morphology in this sample.

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Restinga occurs as a narrow band of coastal habitats throughout the Atlantic Forest, although it presents considerable variation in vegetation structure, which likely contributes to heterogeneity in species inhabiting this endangered ecosystem. The goal of this study is to examine how variation in vegetation and abiotic conditions in the restinga ecosystem may contribute to heterogeneity of bird communities in Restinga de Jurubatiba, Brazil. Temperature, relative humidity, and vegetation structure were sampled to characterize four sites (dry forest, flooded forest, open scrub and closed scrub). Birds were sampled using observations, mist-netting and voice recordings. Results indicate that major differences of all variables occur between forest and scrub in both vegetation and birds. In addition, differences also exist within forests and within scrub, resulting in considerable heterogeneity among sampled areas. Scrub sites were richer in bird species (n = 58) than forest sites (n = 41), while closed scrub had the most species (n = 49). Also, 64% (47 of 73) of bird species were exclusive to forest or scrub habitats. Scrub habitats were more similar to each other than forest habitats. Normalized Difference Vegetation Index (NDVI) calculated from satellite images distinguished scrub sites and may be useful to monitor changes in vegetation patches through time. The restinga ecosystem is quite heterogeneous with considerable turnover in bird species composition and differences in vegetation structure. Forest strips may serve as connectors on the landscape and to help maintain species diversity and conservation of forest species. Also, this highly dynamic ecosystem, which includes a mosaic of habitat types, likely promotes resilience of bird populations under changing conditions.

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Restinga occurs as a narrow band of coastal habitats throughout the Atlantic Forest, although it presents considerable variation in vegetation structure, which likely contributes to heterogeneity in species inhabiting this endangered ecosystem. The goal of this study is to examine how variation in vegetation and abiotic conditions in the restinga ecosystem may contribute to heterogeneity of bird communities in Restinga de Jurubatiba, Brazil. Temperature, relative humidity, and vegetation structure were sampled to characterize four sites (dry forest, flooded forest, open scrub and closed scrub). Birds were sampled using observations, mist-netting and voice recordings. Results indicate that major differences of all variables occur between forest and scrub in both vegetation and birds. In addition, differences also exist within forests and within scrub, resulting in considerable heterogeneity among sampled areas. Scrub sites were richer in bird species (n = 58) than forest sites (n = 41), while closed scrub had the most species (n = 49). Also, 64% (47 of 73) of bird species were exclusive to forest or scrub habitats. Scrub habitats were more similar to each other than forest habitats. Normalized Difference Vegetation Index (NDVI) calculated from satellite images distinguished scrub sites and may be useful to monitor changes in vegetation patches through time. The restinga ecosystem is quite heterogeneous with considerable turnover in bird species composition and differences in vegetation structure. Forest strips may serve as connectors on the landscape and to help maintain species diversity and conservation of forest species. Also, this highly dynamic ecosystem, which includes a mosaic of habitat types, likely promotes resilience of bird populations under changing conditions.(AU)

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Y chromosome markers have been widely studied due to their various applications in the fields of forensic and evolutionary genetics. In this study, 35 Y-SNPs and 17 Y-STRs were genotyped in 253 males from the State of Espirito Santo, Brazil. A total of 18 haplogroups and 243 haplotypes were detected; the haplogroup and haplotype diversities were 0.7794 and 0.9997, respectively. Genetic distance analysis using the Y-STR data showed no statistically significant differences between Espirito Santo and other admixed populations from Brazil. The classification of paternal lineages based on haplogroups showed a predominant European contribution (85.88%), followed by African (11.37%) and Amerindian (2.75%) contributions.

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Genetic diversity of present American populations results from very complex demographic events involving different types and degrees of admixture. Through the analysis of lineage markers such as mtDNA and Y chromosome it is possible to recover the original Native American haplotypes, which remained identical since the admixture events due to the absence of recombination. However, the decrease in the effective population sizes and the consequent genetic drift effects suffered by these populations during the European colonization resulted in the loss or under-representation of a substantial fraction of the Native American lineages. In this study, we aim to clarify how the diversity and distribution of uniparental lineages vary with the different demographic characteristics (size, degree of isolation) and the different levels of admixture of extant Native groups in Colombia. We present new data resulting from the analyses of mtDNA whole control region, Y chromosome SNP haplogroups and STR haplotypes, and autosomal ancestry informative insertion-deletion polymorphisms in Colombian individuals from different ethnic and linguistic groups. The results demonstrate that populations presenting a high proportion of non-Native American ancestry have preserved nevertheless a substantial diversity of Native American lineages, for both mtDNA and Y chromosome. We suggest that, by maintaining the effective population sizes high, admixture allowed for a decrease in the effects of genetic drift due to Native population size reduction and thus resulting in an effective preservation of the Native American non-recombining lineages.

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For the correct evaluation of the weight of genetic evidence in a forensic context, databases must reflect the structure of the population, with all possible groups being represented. Countries with a recent history of admixture between strongly differentiated populations are usually highly heterogeneous and sub-structured. Bolivia is one of these countries, with a high diversity of ethnic groups and different levels of admixture (among Native Americans, Europeans and Africans) across the territory. For a better characterization of the male lineages in Bolivia, 17 Y-STR and 42 Y-SNP loci were genotyped in samples from La Paz and Chuquisaca. Only European and Native American Y-haplogroups were detected, and no sub-Saharan African chromosomes were found. Significant differences were observed between the two samples, with a higher frequency of European lineages in Chuquisaca than in La Paz. A sample belonging to haplogroup Q1a3a1a1-M19 was detected in La Paz, in a haplotype background different from those previously found in Argentina. This result supports an old M19 North-south dispersion in South America, possibly via two routes. When comparing the ancestry of each individual assessed through his Y chromosome with the one estimated using autosomal AIMs, (a) increased European ancestry in individuals with European Y chromosomes and (b) higher Native American ancestry in the carriers of Native American Y-haplogroups were observed, revealing an association between autosomal and Y-chromosomal markers. The results of this study demonstrate that a sub-structure does exist in Bolivia at both inter- and intrapopulation levels, a fact which must be taken into account in the evaluation of forensic genetic evidence.

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Brazil has a large territory divided in five geographical regions harboring highly diverse populations that resulted from different degrees and modes of admixture between Native Americans, Europeans and Africans. In this study, a sample of 605 unrelated males was genotyped for 17 Y-STRs and 46 Y-SNPs aiming a deep characterization of the male gene pool of Rio de Janeiro and its comparison with other Brazilian populations. High values of Y-STR haplotype diversity (0.9999±0.0001) and Y-SNP haplogroup diversity (0.7589±0.0171) were observed. Population comparisons at both haplotype and haplogroup levels showed significant differences between Brazilian South Eastern and Northern populations that can be explained by differences in the proportion of African and Native American Y chromosomes. Statistical significant differences between admixed urban samples from the five regions of Brazil were not previously detected at haplotype level based on smaller size samples from South East, which emphasizes the importance of sample size to detected population stratification for an accurate interpretation of profile matches in kinship and forensic casework. Although not having an intra-population discrimination power as high as the Y-STRs, the Y-SNPs are more powerful to disclose differences in admixed populations. In this study, the combined analysis of these two types of markers proved to be a good strategy to predict population sub-structure, which should be taken into account when delineating forensic database strategies for Y chromosome haplotypes.

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OBJECTIVES: To determine the African, European and Native-American paternal contributions in genetic samples from the Department of Bolivar (Colombia) with the aims of establishing (1) possible population substructures, and (2) the proportion of biological African heritage in admixed populations of European, Amerindian, and African descent. METHODS: Y-SNPs were typed in samples from six communities, including Palenque (renowned for its African linguistic and cultural heritage). RESULTS: Findings reveal a high diversity of Y-haplogroups. With the exception of Palenque, the sum of European male lineages uniformly exceeded 57%. In Palenque, African lineages accounted for 57.7% of its chromosomes, with European male lineages constituting a mere 38.5%. In Pinillos, a significant proportion (23.8%) of the chromosomes belongs to the Native American haplogroup Q1a3a*-M3. Genetic differentiation analyses reveal significant divergences in most pairwise comparisons among the Bolivar municipalities, and the same holds between Bolivar and other South American populations. CONCLUSIONS: Heterogeneous patterns of admixture reveal a genetic substructure within the Department of Bolivar. On the paternal side, five out of the six communities studied exhibit a predominantly European gene pool. The exception is Palenque, where European input (38%) is more significant than we had expected.

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Numerous studies of human populations in Europe and Asia have revealed a concordance between their extant genetic structure and the prevailing regional pattern of geography and language. For native South Americans, however, such evidence has been lacking so far. Therefore, we examined the relationship between Y-chromosomal genotype on the one hand, and male geographic origin and linguistic affiliation on the other, in the largest study of South American natives to date in terms of sampled individuals and populations. A total of 1,011 individuals, representing 50 tribal populations from 81 settlements, were genotyped for up to 17 short tandem repeat (STR) markers and 16 single nucleotide polymorphisms (Y-SNPs), the latter resolving phylogenetic lineages Q and C. Virtually no structure became apparent for the extant Y-chromosomal genetic variation of South American males that could sensibly be related to their inter-tribal geographic and linguistic relationships. This continent-wide decoupling is consistent with a rapid peopling of the continent followed by long periods of isolation in small groups. Furthermore, for the first time, we identified a distinct geographical cluster of Y-SNP lineages C-M217 (C3*) in South America. Such haplotypes are virtually absent from North and Central America, but occur at high frequency in Asia. Together with the locally confined Y-STR autocorrelation observed in our study as a whole, the available data therefore suggest a late introduction of C3* into South America no more than 6,000 years ago, perhaps via coastal or trans-Pacific routes. Extensive simulations revealed that the observed lack of haplogroup C3* among extant North and Central American natives is only compatible with low levels of migration between the ancestor populations of C3* carriers and non-carriers. In summary, our data highlight the fact that a pronounced correlation between genetic and geographic/cultural structure can only be expected under very specific conditions, most of which are likely not to have been met by the ancestors of native South Americans.

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We studied the contribution of understory frugivorous birds to the seed inflow into a late successional Atlantic forest patch in southeastern Brazil. Five sampling units were established in the study site, each composed of a line of six mist nets and two adjacent plots containing six seed traps. Immigrant seed species were more frequent in seed traps during the rainy season, when fruit production was higher. On the other hand, the frequency of occurrence of immigrant seed species found in fecal samples of the understory frugivores was higher during the dry season. Although understory frugivorous birds were not responsible for the temporal pattern of the seed rain, they can play an important role in bringing edge plant species that will eventually colonize forest gaps, contributing to forest patch dynamics.

Estudamos a contribuição de aves frugívoras de subosque para a entrada de sementes em uma mancha de Floresta Atlântica secundária em estado avançado de regeneração no sudeste do Brasil. Foram estabelecidas cinco unidades amostrais, cada uma composta por uma linha de seis redes de neblina e duas parcelas adjacentes contendo seis coletores de sementes. Espécies de sementes imigrantes foram encontradas mais frequentemente nos coletores durante a estação chuvosa, quando houve maior produção de frutos. Por outro lado, a frequência de ocorrência de espécies imigrantes nas amostras fecais de aves de subosque foi maior durante a estação seca. Embora aves frugívoras de subosque não tenham sido determinantes para o padrão temporal da chuva de sementes, podem desempenhar um papel importante ao trazerem espécies de plantas de borda que poderão colonizar clareiras, contribuindo assim para a dinâmica de manchas florestais.

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With this study, we aimed to determine the different male ancestral components of two Native American communities from Argentina, namely Toba and Colla. The analysis of 27 Y-chromosome SNPs allowed us to identify seven different haplogroups in both samples. Chromosomes carrying the M3 mutation, which typically defines the Native American haplogroup Q1a3a, were seen most frequently in the Toba community (90%). Conversely, Q1a3a was represented in 34% of the Colla Y-chromosomes, whereas haplogroup R1b1, the main representative of western European populations, exhibited the highest frequency in this population (41%). Different M3 sublineages in the Toba community could be identified by observing point mutations at both DYS385 and M19 loci. A microvariant at DYS385, named 16.1, has been characterized, which helps to further subdivide Q1a3a. It is the first time the M19 mutated allele is described in a population from Argentina. This finding supports the old age of the lineages carrying the M19 mutation, but it contradicts the previous hypothesis that the M19 mutated allele is confined to only two Equatorial-Tucano population groups from the north region of South America. The detection of M19 further south than previously thought allows questioning of the hypothesis that this lineage serves as an example of isolation after colonization. This observation also affirms the strong genetic drift to which Native Americans have been subjected. Moreover, our study illustrates a heterogeneous contribution of Europeans to these populations and supports previous studies showing that most Native American groups were subjected to European admixture that primarily involved immigrant men.

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Sabendo-se da importância do controle e da remoção do biofilme e do cálculo dental supra e subgengival, para a eliminação do processo inflamatório periodontal, o presente trabalho procurou avaliar comparativamente o efeito da raspagem manual isolada (grupo 1) e associada à irrigação subgengival de bolsas periodontais, utilizando a clorexidina a 0,2% (grupo 2), a solução fitoterápica à base de aroeira (grupo 3) e o soro fisiológico (grupo 4), no tratamento da doença periodontal. O estudo foi desenvolvido em oito pacientes previamente diagnosticados com periodontite crônica, portadores, cada um deles, de quatro bolsas periodontais, com cinco ou mais milímetros de profundidade de sondagem, totalizando uma amostra de 32 dentes, os quais foram submetidos a diferentes tratamentos de acordo com o grupo a que pertenciam. Os parâmetros clínicos avaliados foram: profundidade de sondagem, presença de sangramento gengival e supuração a sondagem. Os dentes dos grupos 2, 3 e 4 receberam irrigação uma vez por semana durante seis semanas consecutivas. Uma semana após a última sessão de irrigação subgengival, todos os dentes foram reavaliados. Os resultados mostraram que todos os grupos apresentaram melhora em relação ao parâmetro clínico profundidade de sondagem, embora apenas o grupo 3 tenha mostrado um resultado estatisticamente significativo. Com relação aos parâmetros de sangramento e supuração a sondagem, os grupos submetidos à irrigação com clorexidina, aroeira ou soro mostraram resultados superiores ao grupo 1, sugerindo assim que a irrigação subgengival com clorexidina, aroeira ou, até mesmo, com soro fisiológico, pode melhorar os efeitos clínicos da raspagem manual.

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Understanding how birds use vegetation to obtain food resources has implications for habitat conservation and management. Restinga is a poorly known and threatened tropical habitat, associated to the Atlantic forest, that could benefit from this kind of information to know which plants can be used and dispersed by birds that can help on the maintenance of this habitat. Frugivorous and insectivorous birds are important components of tropical ecosystems, such as restinga. To provide more information regarding the ecology of restinga, we studied the feeding behavior and spatial use of this vegetation by birds at Restinga de Jurubatiba National Park, southeastern Brazil. We found that feeding behavior was similar to that recorded for the same species in other vegetation types. In addition, spatial use of the restinga vegetation by the most abundant species did not overlap greatly, except for two insectivorous species that used different foraging maneuvers and two frugivorous birds that foraged in flocks. The two most abundant species were generalists in their diet and were capable of feeding at the ground level on sand substrate.

O conhecimento das estratégias de uso da vegetação pela fauna para forrageio tem implicações para conservação e manejo de habitats. Restinga é um ambiente tropical, associado à Mata Atlântica, ameaçado e ainda pouco conhecido que poderia se beneficiar desse tipo de informação para conhecer quais espécies de plantas podem ser utilizadas e dispersas por aves que atuem na manutenção deste habitat. Aves frugívoras e insetívoras são importantes componentes de ecossistemas tropicais, como a restinga. Para fornecer mais informações sobre a ecologia da restinga, nós estudamos o comportamento de forrageio e o uso do espaço das aves no Parque Nacional da Restinga de Jurubatiba, sudeste do Brasil. Nós encontramos que os comportamentos de forrageio foram similares àqueles registrados para as mesmas espécies em outros ambientes. Além disso, o uso do espaço da vegetação de restinga pelas espécies mais abundantes não apresentou grande sobreposição, exceto por duas espécies insetívoras que usaram manobras de forrageio diferentes e duas aves frugívoras que forragearam em bando. As duas espécies mais abundantes foram generalistas em suas dietas e foram capazes de forragear no chão sobre areia nua.

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Restingas are considered stressful habitats associated with the Brazilian Atlantic forest, and their ecological interactions are poorly known. The goal of the present study was to determine the potential role of frugivorous birds as seed dispersers in a restinga habitat. Data were collected in Parque Nacional da Restinga de Jurubatiba, southeastern Brazil, where the main physiognomy (Open Clusia Formation) is characterized by the presence of patches of vegetation covering 20 to 48 % of the sandy soil and reaching a height of 5 m. Birds were captured with mist nets (12 x 2.5 m; 36 mm mesh; 1,680 net-hrs) and had their fecal and regurgitate samples inspected for seeds. Six plant species found in these bird samples were studied. The germination of seeds obtained from plants was compared to those from the birds. Both groups of seeds were set on Petri dishes at room temperature and washed when infected with fungi. In general, there was no effect on germination rate, and the effect on germination speed was negative. Germination of seeds from Pilosocereus arrabidae treated by the birds seemed to be influenced by storage of defecated seeds, while few Miconia cinnamomifolia seeds both from plants and from birds germinated. Ocotea notata presented a great variation in time to the onset of germination, perhaps an advantage against dissecation. Aechmea nudicaulis, Clusia hilariana and Erythroxylum subsessile probably take advantage of the arrival to favorable microhabitats, not by the gut effect on the seeds. All plant species studied are numerically important for the community and some of them are main actors in the succession of vegetation patches. Among the birds, Mimus gilvus is an important resident species, endemic to restingas in Brazil, while Turdus amaurochalinus is a visitor and may be important for plants that fructify during its passage by the study site. Although the effect of pulp removal was only tested for one species (Achmea nudicaulis) in the present study, we confirmed that the tested effect of restinga frugivorous birds on seed germination was generally null. Although there is a need for more detailed studies on specific animal-plant interactions on this habitat, the overall effect of the birds on seed dispersal in restinga is probably positive.

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Restingas are considered stressful habitats associated with the Brazilian Atlantic forest, and their ecological interactions are poorly known. The goal of the present study was to determine the potential role of frugivorous birds as seed dispersers in a restinga habitat. Data were collected in Parque Nacional da Restinga de Jurubatiba, southeastern Brazil, where the main physiognomy (Open Clusia Formation) is characterized by the presence of patches of vegetation covering 20 to 48 % of the sandy soil and reaching a height of 5 m. Birds were captured with mist nets (12 x 2.5 m; 36 mm mesh; 1,680 net-hrs) and had their fecal and regurgitate samples inspected for seeds. Six plant species found in these bird samples were studied. The germination of seeds obtained from plants was compared to those from the birds. Both groups of seeds were set on Petri dishes at room temperature and washed when infected with fungi. In general, there was no effect on germination rate, and the effect on germination speed was negative. Germination of seeds from Pilosocereus arrabidae treated by the birds seemed to be influenced by storage of defecated seeds, while few Miconia cinnamomifolia seeds both from plants and from birds germinated. Ocotea notata presented a great variation in time to the onset of germination, perhaps an advantage against dissecation. Aechmea nudicaulis, Clusia hilariana and Erythroxylum subsessile probably take advantage of the arrival to favorable microhabitats, not by the gut effect on the seeds. All plant species studied are numerically important for the community and some of them are main actors in the succession of vegetation patches. Among the birds, Mimus gilvus is an important resident species, endemic to restingas in Brazil, while Turdus amaurochalinus is a visitor and may be important for plants that fructify during its passage by the study site. Although the effect of pulp removal was only tested for one species (Achmea nudicaulis)...

Las restingas se consideran hábitats estresantes asociados al bosque del Atlántico brasileño y sus ecológicas se conocen poco. El objetivo principal del presente trabajo fue determinar el papel potencial de las aves frugívoras como dispersores de plantas en un hábitat de restinga. La información se recolectó en el Parque Nacional da Restinga de Jurubatiba, Brasil. Las aves se capturaron con redes de niebla y sus muestras fecales y de regurgitación se inspeccionaron en busca de semillas. Estudiamos seis especies de plantas de estas muestras. En general, el efecto del paso por el sistema digestivo de las aves sobre el porcentaje de germinación fue nulo (y negativo en la velocidad de germinación). Todas las especies de plantas estudiadas son numéricamente importantes a la comunidad y algunas de ellas tienen papeles principales en la sucesión de parches de vegetación. Entre las aves, Mimus gilvus es una especie residente importante, endémica de tales hábitats en Brasil, mientras que Turdus amaurochalinus es una especie visitante y puede ser importante para las plantas que fructifican durante su paso por el sitio del estudio. El efecto general de los pájaros en la dispersión de semillas en la restinga es probablemente positivo.

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