The results of a survey of spinturnicid mites (Gamasida: Spinturnicidae) infesting bats near Bras... more The results of a survey of spinturnicid mites (Gamasida: Spinturnicidae) infesting bats near Brasília, D.F., Brazil, are presented. One hundred twenty-five bats were collected, representing three families and 15 species. Seven species of spinturnicid mites (genus Periglischrus) were collected from nine species of bats (family Phyllostomidae). Each of the following six species of Periglischrus was associated with a single species of bat: Periglischrus acutisternus Machado-Allison and P. torrealbai Machado-Allison on Phyllostomus discolor Wagner; P. paravargasi Herrin and Tipton on Anoura caudifer (E. Geoffroy); P. caligus Kolenati on Glossophaga soricina (Pallas); P. ojasti Machado-Allison on Sturnira lilium (E. Geoffroy); P. herrerai Machado-Allison on Desmodus rotundus (E. Geoffroy). P. iheringi Oudemans was collected from four species of bats (Artibeus cinereus (Gervais), A. jamaicensis Leach, A. literatus (Olfers), and Vampyrops lineatus (E. Geoffroy]. No spinturnicids were found on Carollia perspecillata (L.) or on molossid or vespertilionid bats.
Boletim do Museu Paraense Emílio Goeldi - Ciências Naturais
Este estudo avaliou o desempenho e a sobrevivência da castanheira (Bertholletia excelsa Bonpl., L... more Este estudo avaliou o desempenho e a sobrevivência da castanheira (Bertholletia excelsa Bonpl., Lecythidaceae) em três ambientes com diferentes condições de luz em plantios experimentais localizados na região do rio Trombetas (Oriximiná, Pará). Três tratamentos ambientais de exposição à luz: roçados de mandioca abandonados (100% de abertura de dossel), capoeiras jovens (20-80%) e sub-bosque de castanhais (< 10%), com quatro repetições, foram utilizados para o desenvolvimento da pesquisa. Por seis anos, mediram-se as plantas (altura, diâmetro do caule) e registraram-se os episódios de mortalidade e rebrotação. As plantas de castanheira no roçado tiveram um crescimento muito maior, em altura e diâmetro, que as dos outros dois tratamentos. O índice de sobrevivência das castanheiras plantadas variou conforme o tratamento adotado: 90% (roçado), 77% (capoeira) e 21% (sub-bosque de castanhal). A capacidade de rebrotação das plantas de castanheira foi altíssima no tratamento de roçado, r...
This study investigates the distance and patterns of pollen dispersal before and after logging in... more This study investigates the distance and patterns of pollen dispersal before and after logging in a low-density population of the dioecious, insect pollinated tree species, Bagassa guianensis, in the Brazilian Amazon. All adult trees found before and after logging in a 500 ha plot were mapped and genotyped for six microsatellite loci. Seeds collected before and after logging were also sampled and genotyped. We used a categorical paternity analysis to determine seed paternity. Our results showed similar levels of pollen flow before (23%) and after logging (26%), but an increase in the mean effective pollination neighbourhood area, and a decrease in the rate of mating among relatives after logging, resulting in open pollinated seeds with lower levels of inbreeding (0.126) than before logging (0.222). We also detected changes in the mating pattern between before and after logging, a decrease in the median pollen dispersal distance and effective number of pollen donors after logging. Ou...
The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We per... more The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We performed a basin-wide analysis of pre-Columbian impacts on Amazonian forests by overlaying known archaeological sites in Amazonia with the distributions and abundances of 85 woody species domesticated by pre-Columbian peoples. Domesticated species are five times more likely than nondomesticated species to be hyperdominant. Across the basin, the relative abundance and richness of domesticated species increase in forests on and around archaeological sites. In southwestern and eastern Amazonia, distance to archaeological sites strongly influences the relative abundance and richness of domesticated species. Our analyses indicate that modern tree communities in Amazonia are structured to an important extent by a long history of plant domestication by Amazonian peoples.
Analyses of forest loss and protected areas suggest that 36 to 57% of Amazonian tree flora may qu... more Analyses of forest loss and protected areas suggest that 36 to 57% of Amazonian tree flora may qualify as “globally threatened.”
Various techniques have been used to estimate the age of Brazil nut trees (Bertholletia excelsa B... more Various techniques have been used to estimate the age of Brazil nut trees (Bertholletia excelsa Bonpl.), but these techniques produce large discrepancies. Here, we first verified that two individuals of known ages from a plantation in central Amazonia, Brazil, have a congruent number of growth rings. The indexed average tree‐ring curve was significantly correlated with total precipitation during the rainy season (November–June) over a 50‐yr period, confirming the annual nature of the tree rings. Second, we analyzed Brazil nut trees from two populations in the Trombetas (eastern Amazon) and Purus (central Amazon) regions, performing tree‐ring analysis to estimate tree age and diameter increment rates. We compared age–diameter relationships, mean passage time through 10‐cm diameter size classes, and growth trajectories of individual trees. The maximum age of Brazil nut trees analyzed was 361 yr in the Purus and 401 yr in the Trombetas. Trees at the Purus site had higher mean diameter increment rates and showed more variation compared to trees at the Trombetas site. Individual growth trajectories show that the majority of trees attained the canopy by direct growth, while a smaller number passed through one release or one suppression event before becoming established in the canopy. None of the trees passed through multiple release and suppression events. The age estimations presented here are comparable to previous tree‐ring analyses for the species, and the observed growth patterns support earlier work indicating B. excelsa as a gap‐dependent tree species.
Contrary to the theory that geographic isolation is the main trigger for speciation, recent studi... more Contrary to the theory that geographic isolation is the main trigger for speciation, recent studies emphasize the continuous adaptation to different habitats as the driving force initiating diversification. In this way, adaptive divergence in response to contrasting selective pressures of populations of the same species in geographically or ecologically continuous environments may occur if long-lasting barriers are induced by biotic
Introduction Recent decades have seen a major international effort to inventory tree communities ... more Introduction Recent decades have seen a major international effort to inventory tree communities in the Amazon Basin and Guiana Shield (Amazonia), but the vast extent and record diversity of these forests have hampered an understanding of basinwide patterns. To overcome this obstacle, we compiled and standardized species-level data on more than half a million trees in 1170 plots sampling all major lowland forest types to explore patterns of commonness, rarity, and richness. Methods The ~6-million-km 2 Amazonian lowlands were divided into 1° cells, and mean tree density was estimated for each cell by using a loess regression model that included no environmental data but had its basis exclusively in the geographic location of tree plots. A similar model, allied with a bootstrapping exercise to quantify sampling error, was used to generate estimated Amazon-wide abundances of the 4962 valid species in the data set. We estimated the total number of tree species in the Amazon by fitting t...
... These roots are widely used in regional craft manufacture and form part of the extractive ind... more ... These roots are widely used in regional craft manufacture and form part of the extractive industry of the region, based on forest products (Galvão 1959; Milliken et al. ... Typus: Brazil, Amazonas, Manaus, Reserva Florestal Adolfo Ducke, km 0.35 caminho alojamento-torre, 8 Nov. ...
The flowering and fruiting phenology, floral biology, pollination ecology, and breeding system of... more The flowering and fruiting phenology, floral biology, pollination ecology, and breeding system of the emergent tree Ceiba pentandra were studied in the Brazilian Central Amazon. Of the 21 trees studied, 17 flowered once or twice during the 6-y study period. The mass flowering and relatively high production of nectar per flower (mean of 310 μl) resulted in a high nectar production (over 200 l per tree per season). Flowers were visited by a wide range of nocturnal (bats, marsupials, night monkeys, hawk moths) and diurnal (bees, wasps, hummingbirds) animals, but only phyllostomid bats, especially Phyllostomus hastatus and Phyllostomus discolor, played a relevant role promoting cross-pollination. Pollinations which occurred in the early morning by diurnal floral visitors were ineffective since pollen tubes did not traverse the style and reach the ovary before stylar abscission. Despite the apparently normal growth of the self-pollen tubes, controlled pollinations carried out in one tree...
ABSTRACTThe floral biology, breeding system and pollination of Caryocar brasiliense were studied ... more ABSTRACTThe floral biology, breeding system and pollination of Caryocar brasiliense were studied in the cerrado vegetation of Central Brazil. The large, yellowish-cream, brush-like flowers are pollinated mainly by glossophagine bats (Glossophaga soricina and Anoura geoffroyi). Three non-glossophagine bats (Phyllostomus discolor, Vampyrops lineatus and Carollia perspicillata) and two short probosisced hawk moths (Erinyis ello and Pseudosphinx tetrio) may also act as occasional pollinators. Caryocar brasiliense is self-compatible although it sets significantly more fruits when crossed than when selfed. The natural fruit set (fruit/flower ratio) and seed set (seed/ovule ratio) are 3.1% and 1.0% respectively. Most of the fruits and seeds are formed through the action of the flower visitors, despite the fact that about 20% of the non-visited flowers receive self pollen on at least one stigma.
The results of a survey of spinturnicid mites (Gamasida: Spinturnicidae) infesting bats near Bras... more The results of a survey of spinturnicid mites (Gamasida: Spinturnicidae) infesting bats near Brasília, D.F., Brazil, are presented. One hundred twenty-five bats were collected, representing three families and 15 species. Seven species of spinturnicid mites (genus Periglischrus) were collected from nine species of bats (family Phyllostomidae). Each of the following six species of Periglischrus was associated with a single species of bat: Periglischrus acutisternus Machado-Allison and P. torrealbai Machado-Allison on Phyllostomus discolor Wagner; P. paravargasi Herrin and Tipton on Anoura caudifer (E. Geoffroy); P. caligus Kolenati on Glossophaga soricina (Pallas); P. ojasti Machado-Allison on Sturnira lilium (E. Geoffroy); P. herrerai Machado-Allison on Desmodus rotundus (E. Geoffroy). P. iheringi Oudemans was collected from four species of bats (Artibeus cinereus (Gervais), A. jamaicensis Leach, A. literatus (Olfers), and Vampyrops lineatus (E. Geoffroy]. No spinturnicids were found on Carollia perspecillata (L.) or on molossid or vespertilionid bats.
Boletim do Museu Paraense Emílio Goeldi - Ciências Naturais
Este estudo avaliou o desempenho e a sobrevivência da castanheira (Bertholletia excelsa Bonpl., L... more Este estudo avaliou o desempenho e a sobrevivência da castanheira (Bertholletia excelsa Bonpl., Lecythidaceae) em três ambientes com diferentes condições de luz em plantios experimentais localizados na região do rio Trombetas (Oriximiná, Pará). Três tratamentos ambientais de exposição à luz: roçados de mandioca abandonados (100% de abertura de dossel), capoeiras jovens (20-80%) e sub-bosque de castanhais (< 10%), com quatro repetições, foram utilizados para o desenvolvimento da pesquisa. Por seis anos, mediram-se as plantas (altura, diâmetro do caule) e registraram-se os episódios de mortalidade e rebrotação. As plantas de castanheira no roçado tiveram um crescimento muito maior, em altura e diâmetro, que as dos outros dois tratamentos. O índice de sobrevivência das castanheiras plantadas variou conforme o tratamento adotado: 90% (roçado), 77% (capoeira) e 21% (sub-bosque de castanhal). A capacidade de rebrotação das plantas de castanheira foi altíssima no tratamento de roçado, r...
This study investigates the distance and patterns of pollen dispersal before and after logging in... more This study investigates the distance and patterns of pollen dispersal before and after logging in a low-density population of the dioecious, insect pollinated tree species, Bagassa guianensis, in the Brazilian Amazon. All adult trees found before and after logging in a 500 ha plot were mapped and genotyped for six microsatellite loci. Seeds collected before and after logging were also sampled and genotyped. We used a categorical paternity analysis to determine seed paternity. Our results showed similar levels of pollen flow before (23%) and after logging (26%), but an increase in the mean effective pollination neighbourhood area, and a decrease in the rate of mating among relatives after logging, resulting in open pollinated seeds with lower levels of inbreeding (0.126) than before logging (0.222). We also detected changes in the mating pattern between before and after logging, a decrease in the median pollen dispersal distance and effective number of pollen donors after logging. Ou...
The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We per... more The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We performed a basin-wide analysis of pre-Columbian impacts on Amazonian forests by overlaying known archaeological sites in Amazonia with the distributions and abundances of 85 woody species domesticated by pre-Columbian peoples. Domesticated species are five times more likely than nondomesticated species to be hyperdominant. Across the basin, the relative abundance and richness of domesticated species increase in forests on and around archaeological sites. In southwestern and eastern Amazonia, distance to archaeological sites strongly influences the relative abundance and richness of domesticated species. Our analyses indicate that modern tree communities in Amazonia are structured to an important extent by a long history of plant domestication by Amazonian peoples.
Analyses of forest loss and protected areas suggest that 36 to 57% of Amazonian tree flora may qu... more Analyses of forest loss and protected areas suggest that 36 to 57% of Amazonian tree flora may qualify as “globally threatened.”
Various techniques have been used to estimate the age of Brazil nut trees (Bertholletia excelsa B... more Various techniques have been used to estimate the age of Brazil nut trees (Bertholletia excelsa Bonpl.), but these techniques produce large discrepancies. Here, we first verified that two individuals of known ages from a plantation in central Amazonia, Brazil, have a congruent number of growth rings. The indexed average tree‐ring curve was significantly correlated with total precipitation during the rainy season (November–June) over a 50‐yr period, confirming the annual nature of the tree rings. Second, we analyzed Brazil nut trees from two populations in the Trombetas (eastern Amazon) and Purus (central Amazon) regions, performing tree‐ring analysis to estimate tree age and diameter increment rates. We compared age–diameter relationships, mean passage time through 10‐cm diameter size classes, and growth trajectories of individual trees. The maximum age of Brazil nut trees analyzed was 361 yr in the Purus and 401 yr in the Trombetas. Trees at the Purus site had higher mean diameter increment rates and showed more variation compared to trees at the Trombetas site. Individual growth trajectories show that the majority of trees attained the canopy by direct growth, while a smaller number passed through one release or one suppression event before becoming established in the canopy. None of the trees passed through multiple release and suppression events. The age estimations presented here are comparable to previous tree‐ring analyses for the species, and the observed growth patterns support earlier work indicating B. excelsa as a gap‐dependent tree species.
Contrary to the theory that geographic isolation is the main trigger for speciation, recent studi... more Contrary to the theory that geographic isolation is the main trigger for speciation, recent studies emphasize the continuous adaptation to different habitats as the driving force initiating diversification. In this way, adaptive divergence in response to contrasting selective pressures of populations of the same species in geographically or ecologically continuous environments may occur if long-lasting barriers are induced by biotic
Introduction Recent decades have seen a major international effort to inventory tree communities ... more Introduction Recent decades have seen a major international effort to inventory tree communities in the Amazon Basin and Guiana Shield (Amazonia), but the vast extent and record diversity of these forests have hampered an understanding of basinwide patterns. To overcome this obstacle, we compiled and standardized species-level data on more than half a million trees in 1170 plots sampling all major lowland forest types to explore patterns of commonness, rarity, and richness. Methods The ~6-million-km 2 Amazonian lowlands were divided into 1° cells, and mean tree density was estimated for each cell by using a loess regression model that included no environmental data but had its basis exclusively in the geographic location of tree plots. A similar model, allied with a bootstrapping exercise to quantify sampling error, was used to generate estimated Amazon-wide abundances of the 4962 valid species in the data set. We estimated the total number of tree species in the Amazon by fitting t...
... These roots are widely used in regional craft manufacture and form part of the extractive ind... more ... These roots are widely used in regional craft manufacture and form part of the extractive industry of the region, based on forest products (Galvão 1959; Milliken et al. ... Typus: Brazil, Amazonas, Manaus, Reserva Florestal Adolfo Ducke, km 0.35 caminho alojamento-torre, 8 Nov. ...
The flowering and fruiting phenology, floral biology, pollination ecology, and breeding system of... more The flowering and fruiting phenology, floral biology, pollination ecology, and breeding system of the emergent tree Ceiba pentandra were studied in the Brazilian Central Amazon. Of the 21 trees studied, 17 flowered once or twice during the 6-y study period. The mass flowering and relatively high production of nectar per flower (mean of 310 μl) resulted in a high nectar production (over 200 l per tree per season). Flowers were visited by a wide range of nocturnal (bats, marsupials, night monkeys, hawk moths) and diurnal (bees, wasps, hummingbirds) animals, but only phyllostomid bats, especially Phyllostomus hastatus and Phyllostomus discolor, played a relevant role promoting cross-pollination. Pollinations which occurred in the early morning by diurnal floral visitors were ineffective since pollen tubes did not traverse the style and reach the ovary before stylar abscission. Despite the apparently normal growth of the self-pollen tubes, controlled pollinations carried out in one tree...
ABSTRACTThe floral biology, breeding system and pollination of Caryocar brasiliense were studied ... more ABSTRACTThe floral biology, breeding system and pollination of Caryocar brasiliense were studied in the cerrado vegetation of Central Brazil. The large, yellowish-cream, brush-like flowers are pollinated mainly by glossophagine bats (Glossophaga soricina and Anoura geoffroyi). Three non-glossophagine bats (Phyllostomus discolor, Vampyrops lineatus and Carollia perspicillata) and two short probosisced hawk moths (Erinyis ello and Pseudosphinx tetrio) may also act as occasional pollinators. Caryocar brasiliense is self-compatible although it sets significantly more fruits when crossed than when selfed. The natural fruit set (fruit/flower ratio) and seed set (seed/ovule ratio) are 3.1% and 1.0% respectively. Most of the fruits and seeds are formed through the action of the flower visitors, despite the fact that about 20% of the non-visited flowers receive self pollen on at least one stigma.
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