Paleoclimas e especiação em animais da América do Sul tropical

Vanzolini, Paulo Emilio

doi:10.1590/s0103-40141992000200003

Cited by 41 publications

(32 citation statements)

References 12 publications

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“…In accordance with Zartman and Nascimento (2006) and Zartman and Shaw (2006), the fragmentation causes loss of richness and diversity of bryophytes. We believe that the sampling on the great curve of the Xingu River was sufficient to represent the bryoflora of the area, since it is not possible to appoint the necessary sampling effort to achieve the richness of an area (Vanzolini, 1992), and because the richness found corresponds to 23.3% of the bryoflora reported for Pará state.…”

Section: Discussionmentioning

confidence: 99%

Bryophytes in fragments of Terra Firme forest on the great curve of the Xingu River, Pará state, Brazil 1 Part of Master's Dissertation of the first author.

et al. 2015

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Microclimatic conditions of tropical forest favour the high richness of bryophytes, which by being sensitive to environmental changes, are important indicators of habitat conditions. The aim of this study was to determine the richness and species composition of the bryophyte flora in fragments of terra firme forest on the great curve of the Xingu River, Pará state, Brazil. The collections were made in August and September 2012 in 14 fragments, in which were installed two plots per fragment, one at the edge and one inside, measuring 10 × 10 m each. The results showed 77 species in 45 genera and 18 families. Lejeunea setiloba Spruce and Marchesinia brachiata (Sw.) Schiffn. are new records for Pará state. The richness families in this study were the ones typically found in tropical forest surveys. A high richness of rare species in comparison to common ones, a pattern usually observed for plants in tropical forests was not reported in this study, probably due to historical fragmentation and disturbance in the area. The richness and species composition were determined mainly by the physiognomic characteristics of the studied forest fragments.Keywords: brioflora, Amazonian flora, liverworts, mosses. Briófitas em fragmentos florestais de terra firme na região daVolta Grande do Xingu, Pará, Brasil ResumoAs condições microclimáticas das florestas tropicais favorecem elevada riqueza de briófitas, que por serem sensíveis às alterações ambientais, são importantes indicadoras das condições dos habitats. O objetivo deste trabalho foi determinar a riqueza e a composição florística da brioflora de fragmentos florestais de terra firme na região da Volta Grande do Xingu, Pará, Brasil. As coletas foram realizadas em Agosto e Setembro de 2012, em 14 fragmentos e em cada um destes foram plotadas duas parcelas, uma na borda e outra no interior, medindo 10 × 10 m (cada). Foram registradas 77 espécies, distribuídas em 45 gêneros e 18 famílias. Lejeunea setiloba Spruce e Marchesinia brachiata (Sw.) Schiffn. são novos registros para o Pará. As famílias mais ricas neste estudo foram aquelas tipicamente encontradas em levantamentos em florestas tropicais. A elevada riqueza de espécies raras em comparação às comuns, padrão comumente reportado para plantas em florestas tropicais, não foi observada, provavelmente devido ao histórico de fragmentação e distúrbios na área de estudo. A riqueza e a composição de espécies foram determinadas principalmente pelas características fisionômicas dos fragmentos estudados.Palavras-chave: brioflora, flora da Amazônia, hepáticas, musgos.

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Section: Discussionmentioning

confidence: 99%

Bryophytes in fragments of Terra Firme forest on the great curve of the Xingu River, Pará state, Brazil 1 Part of Master's Dissertation of the first author.

et al. 2015

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“…several contributors to multi-author volumes (Duellman, 1979;Prance, 1982;Mares and Genoways, 1982;Prance and Lovejoy, 1985;Whitmore and Prance, 1987), as well as Terborgh (1992) and Vanzolini (1992). Fjeldsa (1994: 219) concluded that Neotropical species probably "differentiate by isolation of relict populations in places which remained ecologically stable, and within geologically well structured regions at the periphery of an old biome" (such as Amazonia).…”

Section: Recent Discussion Of the Refuge Hypothesismentioning

confidence: 99%

Hypotheses to explain the origin of species in Amazonia

Haffer¹

2008

Braz. J. Biol.

180

170

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The main hypotheses proposed to explain barrier formation separating populations and causing the differentiation of species in Amazonia during the course of geological history are based on different factors, as follow: (1) Changes in the distribution of land and sea or in the landscape due to tectonic movements or sea level fluctuations (Paleogeography hypothesis), (2) the barrier effect of Amazonian rivers (River hypothesis), (3) a combination of the barrier effect of broad rivers and vegetational changes in northern and southern Amazonia (River-refuge hypothesis), (4) the isolation of humid rainforest blocks near areas of surface relief in the periphery of Amazonia separated by dry forests, savannas and other intermediate vegetation types during dry climatic periods of the Tertiary and Quaternary (Refuge hypothesis), (5) changes in canopy-density due to climatic reversals (Canopy-density hypothesis) (6) the isolation and speciation of animal populations in small montane habitat pockets around Amazonia due to climatic fluctuations without major vegetational changes (Museum hypothesis), (7) competitive species interactions and local species isolations in peripheral regions of Amazonia due to invasion and counterinvasion during cold/warm periods of the Pleistocene (Disturbance-vicariance hypothesis) and (8) parapatric speciation across steep environmental gradients without separation of the respective populations (Gradient hypothesis). Several of these hypotheses probably are relevant to a different degree for the speciation processes in different faunal groups or during different geological periods. The basic paleogeography model refers mainly to faunal differentiation during the Tertiary and in combination with the Refuge hypothesis. Milankovitch ‡ cycles leading to global main hypotheses proposed to explain barrier formation separating populations and causing the differentiation of species in Amazonia during the course of geological history are based on different factors, as follow: (1) Changes in the distribution of land and sea or in the landscape due to tectonic movements or sea level fluctuations (Paleogeography hypothesis), (2) the barrier effect of Amazonian rivers (River hypothesis), (3) a combination of the barrier effect of broad rivers and vegetational changes in northern and southern Amazonia (River-refuge hypothesis), (4) the isolation of humid rainforest blocks near areas of surface relief in the periphery of Amazonia separated by dry forests, savannas and other intermediate vegetation types during dry climatic periods of the Tertiary and Quaternary (Refuge hypothesis), (5) changes in canopy-density due to climatic reversals (Canopy-density hypothesis) (6) the isolation and speciation of animal populations in small montane habitat pockets around Amazonia due to climatic fluctuations without major vegetational changes (Museum hypothesis), (7) competitive species interactions and local species isolations in peripheral regions of Amazonia due to invasion and counterinvasion during cold/warm p...

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“…A origem dessa diversidade biológica é de interesse dos cientistas desde a época de Darwin e Wallace, no século XIX (Bush e Oliveira 2006). Várias hipóteses tentam explicar os padrões de biodiversidade amazônica como por exemplo: a hipótese dos refúgios de fauna (Haffer 1969;Vanzolini 1992), a hipótese de que existem maiores áreas tropicais que sub-tropicais ou temperadas (Rosenzweig e Sandlin 1997) e a teoria da barreira fluvial (Hershkovitz 1977;van Roosmalen et al 2002). De maneira geral essas hipóteses tratam de barreiras geográficas impostas aos organismos modelos estudados (aves florestais, lagartos e primatas) (Bush e Oliveira 2006).…”

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Morcegos (Mammalia: Chiroptera) da região do Médio Rio Teles Pires, Sul da Amazônia, Brasil

et al. 2015

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A Amazônia é a maior floresta tropical do mundo e pelo menos 147 espécies de morcegos ocorrem neste ambiente. A despeito desta grande riqueza, a diversidade de morcegos da Amazônia é pobremente conhecida e existem grandes lacunas neste conhecimento. O objetivo do presente trabalho foi descrever a assembleia de morcegos ocorrentes na região do Médio Teles Pires (MTP), no sul da Amazônia. Além disso, avaliou-se a similaridade dessa assembleia em relação a 14 assembleias estudadas em outras localidades amazônicas e avaliou-se a correlação entre as similaridades destas localidades e suas distâncias. Trinta e três espécies de morcegos foram registradas, representando 71% das espécies estimadas (Jackknife2). As três espécies com maior abundância relativa foram: Carollia perspicillata, Pteronotus parnellii e Phyllostomus hastatus que somadas contam com mais de 50% das capturas. O grupo funcional dos frugívoros obteve o maior número de espécies capturadas. Foi encontrada uma correlação negativa entre as distâncias e as similaridades das assembleias de morcegos amazônicos (r = -0,22; p = 0,014). A distância geográfica pode explicar apenas 6% da similaridade entre as assembleias analisadas, ainda assim, as similaridades destas assembleias permitem que as mesmas sejam agrupadas por suas distâncias geográficas. Além disso, a fauna de morcegos do MTP é diferenciada de outras áreas da Amazônia o que lhe confere um papel especial na conservação dos morcegos amazônicos. PALAVRAS-CHAVE: Chiroptera, Inventário de fauna, Assembleias, Biodiversidade. Bats (Mammalia: Chiroptera) from the Middle Teles Pires River region, Southern Amazonia, Brazil ABSTRACTAmazonia is the largest tropical rainforest in the world and at least 147 bat species occur in this environment. Despite its richness, the diversity of bat fauna is poorly known for this region and there are large gaps in its knowledge. This study aims to describe the bat assemblage of the Middle Teles Pires River (MTP) region, southern Amazonia. Furthermore, we evaluated the similarity of this assemblage in relation to 14 assemblages studied in other Amazonian localities, and correlations were found between the similarity values among the sites and their geographic distances. Thirty-three bat species were recorded, accounting for 71% of the estimated species richness (Jackknife2). The three species that had the higher relative abundance values were Carollia perspicillata, Pteronotus parnellii and Phyllostomus hastatus, which together accounted for more than 50% of the captures. The frugivore functional group had the highest number of recorded species. A negative correlation was found between the geographic distances and the similarities among the Amazonian bat assemblages (r = -0.22; p = 0.014). Geographic distance could explain only 6% of the similarities among the analyzed assemblages, even though, the similarity found allowed them to be grouped by their distances. Besides, the MTP bat fauna is different from other Amazonian areas, which gives it a special role in the Amazonian ba...

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Paleoclimas e especiação em animais da América do Sul tropical

Cited by 41 publications

References 12 publications

Bryophytes in fragments of Terra Firme forest on the great curve of the Xingu River, Pará state, Brazil 1 Part of Master's Dissertation of the first author.

Bryophytes in fragments of Terra Firme forest on the great curve of the Xingu River, Pará state, Brazil 1 Part of Master's Dissertation of the first author.

Hypotheses to explain the origin of species in Amazonia

Morcegos (Mammalia: Chiroptera) da região do Médio Rio Teles Pires, Sul da Amazônia, Brasil

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