The igapó of the Negro River in central Amazonia: Linking late-successional inundation forest with fluvial geomorphology

Despite important progress on Amazonian floodplain research, the flooded forest of the Negro River igapó has been little investigated. In particular, no study has previously focused the linkage between fluvial geomorphology and the floristic variation across the course of the river. In this paper we describe and interpret relations between igapó forest, fluvial geomorphology and the spatial evolution of the igapó forest through the Holocene. Therefore, we investigate the effect of geomorphological units of the floodplain and channel patterns on tree diversity, composition and structural parameters of the late-successional igapó forest. Our results show that sites sharing almost identical flooding regime, exhibit variable tree assemblages, species richness and structural parameters such as basal area, tree density and tree heights, indicating a trend in which the geomorphologic styles seem to partially control the organization of igapó's tree communities. This can be also explained by the high variability of well-developed geomorphologic units in short distances and concentrated in small areas. In this dynamic the inputs from the species pool of tributary rivers play a crucial role, but also the depositional and erosional processes associated with the evolution of the floodplain during the Holocene may control floristic and structural components of the igapó forests. These results suggest that a comprehensive approach integrating floristic and geomorphologic methods is needed to understand the distribution of the complex vegetation patterns in complex floodplains such as the igapó of the Negro River. This combination of approaches may introduce a better comprehension of the temporal and spatial evolutionary analysis and a logic rationale to understand the vegetation distribution and variability in function of major landforms, soil distributions and hydrology. Thus, by integrating the past into macroecological analyses will sharpen our understanding of the underlying forces for contemporary floristic patterns along the inundation forests of the Negro River. © 2013 Elsevier Ltd.

The Phylogeographic History of the New World Screwworm Fly, Inferred by Approximate Bayesian Computation Analysis

Insect pest phylogeography might be shaped both by biogeographic events and by human influence. Here, we conducted an approximate Bayesian computation (ABC) analysis to investigate the phylogeography of the New World screwworm fly, Cochliomyia hominivorax, with the aim of understanding its population history and its order and time of divergence. Our ABC analysis supports that populations spread from North to South in the Americas, in at least two different moments. The first split occurred between the North/Central American and South American populations in the end of the Last Glacial Maximum (15,300-19,000 YBP). The second split occurred between the North and South Amazonian populations in the transition between the Pleistocene and the Holocene eras (9,100-11,000 YBP). The species also experienced population expansion. Phylogenetic analysis likewise suggests this north to south colonization and Maxent models suggest an increase in the number of suitable areas in South America from the past to present. We found that the phylogeographic patterns observed in C. hominivorax cannot be explained only by climatic oscillations and can be connected to host population histories. Interestingly we found these patterns are very coincident with general patterns of ancient human movements in the Americas, suggesting that humans might have played a crucial role in shaping the distribution and population structure of this insect pest. This work presents the first hypothesis test regarding the processes that shaped the current phylogeographic structure of C. hominivorax and represents an alternate perspective on investigating the problem of insect pests. © 2013 Fresia et al.

Multilocus molecular phylogeny of Gasteropelecidae (Ostariophysi: Characiformes) reveals the existence of an unsuspected diversity

The characiform family Gasteropelecidae, the so-called freshwater hatchetfishes, is comprised of three genera and nine species found in Panama and all South American countries except Chile. Our goal was to investigate the molecular characteristics, phylogenetic relationships among the species and genera of Gasteropelecidae and phylogenetic relationships between the Gasteropelecidae family with other Characiformes. DNA fragments from two mitochondrial (16S rRNA and Cytochrome B) and three nuclear genes (Rag1, Rag2 and Myh6) were sequenced. Our results corroborate the morphology-based hypothesized monophyly of the Gasteropelecidae family and most of the relationships among its genera. However, the genus Gasteropelecus is polyphyletic because G. maculatus is placed as the sister group to all other gasteropelecids, whereas G. sternicla is more closely related to species of Carnegiella. Similarly, the species Carnegiella strigata is not monophyletic, which suggests that the family needs a taxonomic review. Moreover, the species Thoracocharax stellatus was composed by four distinct lineages suggesting the this species may represents a species complex. © 2013 Elsevier Inc.

Desenvolvimento ovariano do Prochilodus lineatus em dois sistemas de produção: tanques rede e viveiros escavados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Resfriamento de embriões de pacu, Piaractus mesopotamicus (Holmberg, 1887) em diferentes fases do desenvolvimento ontogenético

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estrutura e evolução cariotípica de peixes ciclídeos sul americanos

Pós-graduação em Biologia Geral e Aplicada - IBB

Comportamento reprodutivo e cooperação no ciclídeo neotropical Laetacara sp

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relação de custo/benefício na interação entre a aranha Peucetia flava (Oxyopidae) e a planta Rhynchanthera dichotoma (Melastomataceae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O papel da America do Sul na inserção internacional do Brasil: uma análise do governo de Luiz Inácio Lula da Silva (2003-2010)

Pós-graduação em Ciências Sociais - FCLAR

Direitos humanos: perfil sul-americano de cumprimento das decisões da Corte Interamericana

Pós-graduação em Ciências Sociais - FFC

Bioecologia de Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae) em videira

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Caracterização molecular e bioquímica de uma esterase macho-específica em Zaprionus indianus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Geoarqueologia e paleoidrologia da planicie aluvial holocênica do alto Rio Madeira entre Porto Velho e Abunã - RO

Pós-graduação em Geociências e Meio Ambiente - IGCE

Evolução termocronológica do sudoeste de Angola e correlação com o sudoeste brasileiro: termocronologia por traços de fissão em apatita

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

ALBA-TCP: uma cultura de integração regional alternativa para a América Latina?

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)