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Shepard Jr. G.H.,Museu Paraense Emilio Goeldi | Ramirez H.,Federal University of Rondonia
Economic Botany | Year: 2011

"Made in Brazil": Human Dispersal of the Brazil Nut (Bertholletia excelsa, Lecythidaceae) in Ancient Amazonia. The Brazil nut, Bertholletia excelsa, is a colossal tree of terra firme forest whose seeds represent the most important non-timber forest product in Amazonia. Its peculiarly inefficient dispersal strategy and discontinuous distribution have led some to hypothesize anthropogenic origins, but evidence to date has been inconclusive. Here we present results of a multidisciplinary study addressing this question. A review of the geographic distribution of B. excelsa and comparison with that of similar Lecythis species suggest a number of anomalies that are consistent with a recent and wide colonization of Bertholletia. Published studies and field observations indicate that anthropogenic disturbance facilitates Brazil nut regeneration. Recent genetic studies showing no sequence diversity and no geographical structuring of within-population variability support a rapid and recent irradiation from an ancestral population. Historical linguistic analysis of indigenous terms for Brazil nut suggests a northern/eastern Amazonian origin for Bertholletia, with a concomitant spread of Brazil nut distribution or cultivation to the south and west. Such an expansion would have been particularly facilitated by the emergence of intensive bitter manioc cultivation and networks of interethnic trade beginning in the first millennium C. E. Together, ecological, phytogeographic, genetic, linguistic, and archeological data reinforce the hypothesis that ancient Amazonian peoples played a role in establishing this emblematic and economically important rainforest landscape. © 2011 The New York Botanical Garden.

Fernandes A.M.,University of Heidelberg | Wink M.,University of Heidelberg | Aleixo A.,Museu Paraense Emilio Goeldi
Journal of Biogeography | Year: 2012

Aim We examined patterns of spatial and temporal diversification of the Amazonian endemic chestnut-tailed antbird, Mymeciza hemimelaena (Thamnophilidae), to evaluate the diversification of a widespread avian taxon across rivers that potentially represent major natural barriers. Location Lowland Amazonia. Methods Sequences of the mitochondrial ND2 and cytochrome b genes were investigated from 65 individuals distributed throughout the entire range of M. hemimelaena, and including the two currently valid subspecies M. h. hemimelaena and M. h. pallens. Based on a combination of phylogeographic tools, molecular dating, and population genetic methods, we reconstructed a spatio-temporal scenario of diversification of M. hemimelaena in the Amazon. Results The data revealed three genetically divergent and monophyletic groups in M. hemimelaena, which can also be distinguished by a combination of morphological and vocal characters. Two of these clades correspond to the previously described taxa M. h. hemimelaena and M. h. pallens, which are separated by the upper Madeira River, a main Amazonian tributary. The third clade is distributed between the middle reaches of the Madeira River and the much smaller tributaries Jiparaná and Aripuanã, and, although currently treated as M. h. pallens, clearly constitutes an independent evolutionary lineage probably deserving separate species status. Molecular clock and population genetic analyses indicate that diversification in this group occurred throughout the Pleistocene, with demographic fluctuations assumed for M. h. hemimelaena and M. h. pallens. Mainconclusions The findings implicate rivers as barriers driving diversification in the M. hemimelaena complex. Levels of mitochondrial DNA divergence and associated morphological and vocal traits support its division into at least three separate species with comparatively small ranges. The existence of a previously unrecognized lineage in the M. hemimelaena complex, and the high degree of population structuring found in M. h. hemimelaena underscore the pervasiveness of cryptic endemism throughout Amazonia and the importance of DNA-based taxonomic and phylogeographic studies in providing the accurate estimates of diversity that are essential for conservation planning. © 2012 Blackwell Publishing Ltd.

Borges S.H.,Museu Paraense Emilio Goeldi | Da Silva J.M.C.,Conservation International Do Brazil
Wilson Journal of Ornithology | Year: 2012

We describe a new area of endemism for Amazonian birds which we designate as the Jaú Area of Endemism. This area of endemism in central-western Amazonia north of the Rio Solimões was identified through congruent distributions of six avian taxa: Psophia crepitans ochroptera Pelzeln 1857, Nonnula amaurocephala Chapman 1921, Pteroglossus azara azara Vieilot 1819, Picumnus lafresnayi pusillus Pinto 1936, Synallaxis rutilans confinis Zimmer 1935, and Myrmoborus myotherinus ardesiacus Todd 1927. The southern and eastern limits of this area of endemism are the middle courses of the Solimões and Negro rivers, respectively. The northern limits apparently coincide with sandy soil vegetation along the middle Rio Negro. The western boundary remains undefined, but could involve the Japur or I rivers north of the upper Solimões. Taxonomic studies and expansion of ornithological collections are needed to more precisely delimit the Jaú Area of Endemism. It is possible the avian taxa restricted to the Jaú Area of Endemism are derived through parapatric or peripatric speciation events from taxa whose ranges were centered in the Imeri and Napo areas of endemism. Alternatively, tectonic events that affect the lower course of the Rio Negro could influence bird distribution in this region if they serve as vicariance mechanisms. © 2012 by the Wilson Ornithological Society.

Fernandes A.M.,University of Heidelberg | Gonzalez J.,University of Heidelberg | Wink M.,University of Heidelberg | Aleixo A.,Museu Paraense Emilio Goeldi
Molecular Phylogenetics and Evolution | Year: 2013

Amazonian rivers function as important barriers to dispersal of Amazonian birds. Studying population genetics of lineages separated by rivers may help us to uncover the dynamics of biological diversification in the Amazon. We reconstructed the phylogeography of the Wedge-billed Woodcreeper, Glyphorynchus spirurus (Furnariidae) in the Amazon basin. Sampling included 134 individuals from 63 sites distributed in eight Amazonian areas of endemism separated by major Amazonian rivers. Nucleotide sequences were generated for five genes: two mtDNA genes (1047. bp for cyt b and 1002. bp for ND2) and three nuclear genes (647. bp from the sex-linked gene ACO, 319. bp from the intron of G3PDH, and 619. bp from intron 2 of MYO). In addition, 37 individuals were randomly selected from the Rondônia and Inambari areas of endemism for genomic fingerprinting, using five ISSR primers. Our results reveal allopatric and well-supported lineages within G. spirurus with high levels of genetic differentiation (p-distances 0.9-6.3%) across opposite banks of major Amazonian rivers. The multilocus phylogenetic reconstructions obtained reveal several incongruences with current subspecies taxonomy. Within currently recognized subspecies, we found high levels of both paraphyly and genetic differentiation, indicating deep divergences and strong isolation consistent with species-level differences. ISSR fingerprinting supports the existence of genetically differentiated populations on opposite sides of the Madeira River. Molecular dating suggests an initial vicariation event isolating populations from the Guiana center of endemism during the Late Miocene/Early Pliocene, while more recent events subdivided Brazilian Shield populations during the Lower Pleistocene. © 2012 Elsevier Inc.

Alfaro J.W.L.,University of California at Los Angeles | Silva Jr. J.S.E.,Museu Paraense Emilio Goeldi | Rylands A.B.,Wildlife Conservation Society
American Journal of Primatology | Year: 2012

Capuchin monkey behavior has been the focus of increasing numbers of captive and field studies in recent years, clarifying behavioral and ecological differences between the two morphological types: the gracile and the robust capuchins (also referred to as untufted and tufted). Studies have tended to focus on the gracile species Cebus capucinus (fewer data are available for C. albifrons, C. olivaceus, and C. kaapori) and on Cebus apella, a name that has encompassed all of the robust capuchins since the 1960s. As a result, it is difficult to ascertain the variation within either gracile or robust types. The phylogenetic relationships between gracile and robust capuchins have also, until now, remained obscure. Recent studies have suggested two independent Pliocene radiations of capuchins stemming from a common ancestor in the Late Miocene, about 6.2 millions of years ago (Ma). The present-day gracile capuchins most likely originated in the Amazon, and the robust capuchins in the Atlantic Forest to the southeast. Sympatry between the two types is explained by a recent expansion of robust capuchins into the Amazon (ca. 400,000 years ago). Morphological data also support a division of capuchins into the same two distinct groups, and we propose the division of capuchin monkeys into two genera, Sapajus Kerr, 1792, for robust capuchins and Cebus Erxleben, 1777, for gracile capuchins, based on a review of extensive morphological, genetic, behavioral, ecological, and biogeographic evidence. © 2012 Wiley Periodicals, Inc.

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